PASIG CITY SCIENCE HIGH SCHOOL
F. Legaspi St., Rainforest Park, Maybunga, Pasig City, Philippines 1600
Pyrus pyrifolia (Asian Pear) Waste, Brassica oleracea L. var. capitata f, rubra (Red
Cabbage), and Carboxymethyl Cellulose (CMC) for Food Packaging Production
In Partial Fulfillment of the Requirements
in Research/Capstone Project
By:
Arcabal, Claude Henry S.
Benoza, Alexie Mignonette E.
Carpio, Jass Myne R.
Clavecillas, Irene I.
June 30, 2023
Acknowledgment
The researchers sincerely thank their research adviser, Mr. Nico Risos, for his
guidance and support throughout this study. Thanks are also due to Miss Cynthia
Quiogue, the chemistry laboratory head, for her assistance and valuable insights in
conducting the experimental work. The researchers express their gratitude to Pasig City
Science High School for providing them with the necessary resources and facilities for
this study. The researchers' scientific endeavors have been shaped by the conducive
learning environment and supportive faculty. The researchers also sincerely thank
Advanced Device and Materials Testing Laboratory (ADMATEL). Access to advanced
analytical instruments, including the Fourier transform infrared (FTIR) spectrometer,
which played a pivotal role in the characterization of the cellulose-based paper, was
provided to them through their state-of-the-art facilities and technical expertise. Again,
the researchers are deeply grateful to all individuals and institutions mentioned above for
their valuable contributions, without which this research would not have been possible.
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Abstract
The escalating issue of food waste and environmental harm caused by plastic packaging
necessitates sustainable alternatives. This research aims to develop a durable and efficient
food packaging using Pyrus pyrifolia (Asian Pear) waste, Brassica oleracea L. var.
capitata f, rubra (Red Cabbage), and Carboxymethyl Cellulose (CMC). The study
explores the effectiveness of the packaging through durability, efficiency, and color
alteration evaluations. By utilizing P. pyrifolia waste, B. oleracea, and CMC, food waste
can be reduced, trees can be conserved, and food poisoning can be prevented. The
researchers employed a quantitative method, including posttest-only control group
design, FTIR spectroscopy, methanol testing, weight capacity, and pH tests. Statistical
analysis, such as one-way ANOVA, was conducted to analyze the data collected. The
optimal composition for food packaging was determined to be 500g of P. pyrifolia waste,
180g of B. oleracea, and 120g of CMC. The packaging exhibited superior durability,
withstanding weights up to 5 kilograms compared to regular paper. The extraction of
anthocyanin from B. oleracea was effective, with a 50% water and 50% methanol
solution proving safe and successful. FTIR analysis confirmed the presence of functional
groups, supporting the paper's durability and potential applications. This research
contributes to sustainable packaging development, product quality enhancement, and
environmental preservation. Future studies are recommended to explore additional tests,
alternative anthocyanin sources, and other packaging types for a broader understanding of
their accuracy and applicability.
Keywords: Pyrus pyrifolia waste, Brassica oleracea, carboxymethyl cellulose,
sustainability, food packaging
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Contents
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List of Figures
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List of Tables
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CHAPTER 1
INTRODUCTION
Background of the Study
This part of the research will tackle the growing issue regarding food waste,
explicitly finding an answer to solve the food waste of Pyrus pyrifolia, known as the
Asian pear. P. pyrifolia is a type of pear tree that is indigenous to East Asia. It is a rather
nutrient-dense fruit; it is particularly high in fiber, vitamin C, vitamin K, potassium,
copper, and antioxidants. Because chemical processing is mild on the cellulose fiber,
chemical pulps typically have longer fibers and produce robust paper like printing and
writing papers and paperboard (EPA, 2016). According to Markey (2021), “Some
360,500 tonnes of apples and pears colour our soil every year." It results in carbon
emissions which are the main contributor to global warming. In light of this, the
researchers decided to use food waste, specifically the food waste of P. pyrifolia to
manufacture food packaging. They do away with the need for single-use plastic bags and
food packaging, which results in helping the environment, and solely recycle waste
materials which in this research case is the use of P. pyrifolia waste.
The researchers have decided to use P. pyrifolia waste and its fiber contents to
create and manufacture paper food packaging. Compared to regular packaging, these are
more robust and long-lasting. According to UNEP.org (2022), “Today, we produce about
400 million tonnes of plastic waste every year.” And the Philippines is one of the nations
responsible for 80% of the annual global riverine plastic emissions into the ocean, which
varies from 0.8 to 2.7 million tonnes annually, with small urban rivers being among the
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most polluted. At Dole's farms in the Philippines, nearly a million tons of fruit side
stream are produced annually, equivalent to 50,000 hectares in size or 40-foot containers.
(Ochave, 2021). Pears and apples are the leading fruit side streams that contribute to the
main issue of food waste here in the Philippines. There are various kinds of apple and
pear pomace powders with varied particle sizes, including fine, medium, and coarse, and
it is well-known that they contain a lot of fiber. Each one is unique, and some degrade
more quickly than others, such as the coarse apple and pear pomace powders, which get
trapped along the greenhouse gases that are the primary cause of climate change.
Pollution results in health risks for people and contributes to global warming, and
eliminating one of the food waste, P. pyrifolia, and using it to create an alternative for
plastic bags will result in less plastic waste and building a healthier community. The
researchers aim to assess if P. pyrifolia is a compatible component in making paper food
packaging.
Furthermore, the researchers have decided to include other ingredients such as
carboxymethyl cellulose (CMC) and extracts of Brassica oleracea L. var. capitata f,
rubra (Red Cabbage) to further improve the quality of the food packaging.
Carboxymethyl cellulose or cellulose gum is widely used in food products to absorb and
hold water, control crystal growth, thicken, as a binder, increase shelf life, and provide
desired texture or body. This is used to strengthen the paper, as it is commonly used. On
the other hand, the extracts of red cabbage shall be used to coat the paper in an oil-like
substance called anthocyanin, which are red or purple pigments found in plants.
Anthocyanin is the substance that induces color-changing properties in litmus paper.
Litmus paper tests the pH levels of substances; in other words, it determines whether a
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substance is a base or an acid. Due to this, the researchers have decided to coat their food
packaging in this substance to have it change color when in contact with spoiled food.
According to the World Health Organization (WHO, 2022), an estimated 600 million fall
ill after eating contaminated food and 420 000 die every year. This study aims to prevent
this phenomenon and the food and plastic waste problems that plague our environment
and health each year.
This study aims to determine whether Pyrus pyrifolia (Asian Pear), Brassica
oleracea L. var. capitata f, rubra (Red Cabbage), and carboxymethyl cellulose would be
effective ingredients in the production of food packaging.
Statement of the Problem
Food waste worsens the pollution in land, air, and water pollution. The
Department of Science and Technology Research Institute (DOST-RI) stated that one
thousand seven hundred seventeen metric tons of food are wasted each day (Dela Pena,
2021). A large amount of food waste consists of fruits such as apples, oranges, and pears.
In light of this, the study aims to use Pyrus pyrifolia (Asian pear) waste and fibers as
alternatives in manufacturing food paper packaging with the help of carboxymethyl
cellulose (CMC) and anthocyanin. CMC is the most widely used co-binder and rheology
modifier in paper coating, which can add durability to paper food packaging made from
Asian pear waste. Brassica oleracea L. var. capitata f, rubra (Red Cabbage) contains
anthocyanin, which causes litmus paper to change colors. The researchers also aim to
answer the following questions.
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1. How much Pyrus pyrifolia waste, Brassica oleracea extracts, and carboxymethyl
cellulose is needed to manufacture a single food packaging?
2. What concentration of B. oleracea extracts is needed to accurately determine food
spoilage?
3. What is the difference between the quality of food packaging made of P. pyrifolia
wastes, Brassica oleracea extracts, and carboxymethyl cellulose and conventional
food packaging in terms of the following:
a. FTIR Analysis Result
b. Stripping Quality
c. Effectiveness of color-alteration
Hypothesis
Null Hypothesis: Pyrus pyrifolia (Asian Pear), Brassica oleracea L. var. capitata f, rubra
(Red Cabbage), and carboxymethyl cellulose are ineffective components in producing
food packaging due to frail durability and toughness.
Alternative Hypothesis: Pyrus pyrifolia (Asian Pear), Brassica oleracea L. var. capitata
f, rubra (Red Cabbage), and carboxymethyl cellulose can be used to manufacture food
packaging that possess exceptional durability and toughness.
Scope and Delimitations
An experimental study was utilized to determine the capacity of Pyrus pyrifolia
(Asian Pear), Brassica oleracea L. var. capitata f, rubra (Red Cabbage), and
carboxymethyl cellulose for the production of food packaging. This study only made use
of the aforementioned materials. The waste products of P. pyrifolia were collected from
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markets or households that discard the unwanted component of the fruit. The P. pyrifolia
waste were the primary ingredient, the Carboxymethyl Cellulose (CMC) was the
secondary ingredient, and the Brassica oleracea extracts were the tertiary products. The
study aimed to manufacture biodegradable food packaging from Pyrus pyrifolia (Asian
Pear), Brassica oleracea L. var. capitata f, rubra (Red Cabbage), and carboxymethyl
cellulose.
The researchers tested the durability of the biodegradable food packaging and saw
its efficiency in determining spoiled food. The experiment was conducted to determine
how much P. pyrifolia waste and Carboxymethyl Cellulose (CMC) were required to make
a single food packaging, and other components include red cabbage that contains
anthocyanin. The study used P. pyrifolia instead of regular pears because Asian pears are
commonly grown in East Asia, including the Philippines, making it easier for the
researchers to acquire materials. However, due to time constraints in this study, the
researchers were only able to test the deterioration period of the food packaging. The
researchers did not conduct other tests like COBB measurement and burst strength due to
the lack of equipment and facilities for these tests. Furthermore, the research was
conducted in an open area and in laboratories. The data gathered were based on the
durability and components required to strengthen biodegradable food packaging.
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Significance of the Study
The study seeks to determine whether using P. pyrifolia waste to manufacture
food packaging would be effective. The use of Pear waste in manufacturing food
packaging would help lessen food waste as well as contribute to saving trees from being
exploited. This study would be beneficial for the following:
Environment. The study will benefit environmentalists as it will help lessen the
overwhelming amount of food waste in the world, which is a major contributor to
pollution. Moreover, this will help reduce the excessive amount of tree cutting.
Food corporations. These corporations will benefit from the study as it can give
them alternative packaging to use for their products to help their company, customers,
and the environment. The study shall lessen their expenses and wastes while at the same
time satisfying their customers.
Food packaging manufacturers. These people will profit from this study
because they will be able to find an alternative material to make their products that will
not harm the environment. Pear waste as food packaging will also result in less capital
needed for them to produce their items.
Households. These people will benefit from the study as it shall give them a new
and efficient way to store their products that helps them prevent spoilage of food or the
consumption of spoiled food in a much more sustainable and inexpensive way. It is also a
much healthy and less toxic alternative to other food packaging.
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People in flood prone areas. These people will benefit from this study as it
prevents trees necessary for fending off floods from being exploited by food packaging
manufacturers. This study will help in experiencing fewer floods inside flood-prone
areas.
Pear consumers. Pear consumers will benefit from this study as the
standardization of P. pyrifolia food packaging will give them a place to deposit the waste
from the pears they consume or use.
Future researchers. This study will benefit future researchers as the outcome of
this study could become a reference for future researchers that can serve as another piece
of evidence for their claim.
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CHAPTER 2
REVIEW OF RELATED LITERATURE AND STUDIES
The review of related literature and studies that served as the foundation for the
current study is presented in this chapter.
Several studies and literature have been published related to Pyrus pyrifolia being
manufactured into food packaging. The following discussions offer authors' perspectives
and insights on the ongoing investigation.
Papermaking and the Environment
Environmental degradation is a phenomenon where the environment and its
natural resources begin to deteriorate. In the Asia Pacific region, there have been records
showing that deforestation has been one of the significant environmental concerns.
(Jhansi & Mishra, n.d.). One of the reasons for the widespread deforestation in the world
is papermaking. Paper is created from shredded leaves. According to Ribble (2018), our
usage of paper has increased by 400% in the last 40 years. Such data would mean that
over two million trees are cut daily for paper. In a live counter by The World Counts
(2022), it is shown that 302,103,119 tons of paper have been produced in 2022 so far.
Moreover, 22,689,030 tons of paper were produced this month, 1,992,236 tons this week,
and 842,735 tons today. Given that to produce one ton of paper, 24 trees must be cut,
which shows how much environmental impact papermaking causes (Kiprop, 2018).
Nearly 4,000 years ago, ancient people made paper from plants and trees. As time
pass by, different companies use this knowledge to provide writing material for those
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who need it. Since money is involved, people have gone uncontrollable over the years as
they continue to cut down trees for paper-making. The mass production led to terrible
deforestation. According to KhawarPaperMart (2017), "Around 3 Trillion trees are cut
down annually" to produce paper all around the globe. According to the United Nations
Food and Agriculture Organization (2017), "we are losing around thirty-three million
acres of forestland annually," accounting for 20% of human-generated gas emissions.
Although there are still a lot of paper companies that worsen the Earth's deforestation,
there are still different groups who wish to lessen the deforestation rate by reducing the
production of paper using wood. One of the standard solutions is to use alternatives. In
2007, Alberto Volcan, an Italian Inventor, manufactured paper using apples. He also used
the technique to produce 60,000 envelopes and 7,000 notebooks to be donated as office
needs. (Winters, 2018) “This recycling will significantly impact the industry and the
environment.” said Governor Luis Durnwalder. Another solution for lessening
deforestation is reducing paper consumption, such as using erasable boards, writing
digitally or using technology, setting a low-paper production directive, and recycling used
paper.
On a related note, trees are responsible for stabilizing the soil, storing carbon,
supplying oxygen, supporting a variety of species, and providing us with the resources
we need for tools and housing (Turner‐Skoff & Cavender, 2019). Unfortunately, the
world loses approximately 7 billion to 35 billion trees each year. The Philippines alone
has lost 1,288,911 hectares of forests from 2002 until 2020 (Butler, 2020). Subsequently,
deforestation causes different environmental catastrophes, such as floods, climate change,
desertification, and soil erosion. This phenomenon also causes animals to lose their
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natural habitat, which could lead to the mass death of forest animals (“Effects of
Deforestation”, 2022).
Although paper has been considered a necessity over the years, its mass
production can negatively affect it. People starting to use alternatives and lowering paper
consumption seems like a difficult step, but it will enormously impact everyone and
everything on Earth. The lower the deforestation rate, the lower the risk of organisms
dying. It will not only change and preserve the planet but also save lives.
Annual Pear and Fruit Waste Problem
Food waste is a significant problem environmentally, economically, and for food
security reasons. The term “waste” refers to food that is fit for consumption but
consciously discarded at the retail or consumption phases. Fortier (2021) states, “Food
waste is one of the most pressing environmental, social, and political problems facing the
globe today.”This specific problem has been polluting the Earth for many years. Despite
the persistent problem of world hunger and poverty, tons of food are wasted annually in
different parts of the world. This study will focus more on one type of food waste – fruit
waste, specifically pear. 1.03 billion tonnes of fruit waste are generated globally annually,
valued at USD 2.6 trillion, and sufficient to feed the world's 815 million hungry four
times over
(United Nations Environment, n.d). A study by Future Directions
International (FDI), a non-profit institute, found that South and Southeast Asia accounts
for 25% of the globe's fruit waste. According to Ochave (2021), “Around 1 million tons
of fruit waste is produced in the Philippines annually”. In Asia, 32 million tons of fruit
and vegetables are wasted yearly (UNE, n.d.). According to the statistics of fruits wasted
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in an experiment conducted in 2013, the pear ranks 8th most enormous amount of wasted
mass in Sweden (Mattson, 2018), making pear a large part of the total annual food waste.
If this problem continues, it will have a tremendous negative impact on Earth. As
part of the fruit waste problem, Pear significantly damages the planet as it decomposes
and releases Methane. Scientists believe this greenhouse gas affects the Earth’s climate
and temperature (Hawthorne, 2022). As pear waste adds to the amount of Methane in
Earth’s greenhouse gasses, global warming may cause around a million deaths yearly.
According to New Food’s Hawthorne (2022), “about 99% of the waste occurs on land
with extremely high levels of degradation,” which puts much stress on lands that become
a factor that stops crops from growing. This effect results in food scarcity, where lands
produce far less than can sustain the people living in a region (Williams, 2018). As the
pear waste problem continues to rise, “DOLE Sunshine Co. (DSC) plans to repurpose
around 1 million tons of fruit waste generated by its plantations in the Philippines under a
recently created corporate venture,” as stated by Ochave (2021). The plantations put in
efforts to reduce fruit losses by repurposing fruit parts and side streams into ingredients
such as seed oils, fibers, and enzymes to be used in pharmaceuticals, food and beverages,
and other industries (DSC,2021).
Despite the resolution presented by DOLE Sunshine Co, the problem with pear
waste remains ongoing as of 2022. Although a well-known, big fruit company plans to
repurpose fruit waste, there are a few suggestions for people who buy and consume these
fruits. In conclusion, fruit waste still impacts Earth in many ways that can negatively
affect people’s lives in the next few years if it continues to pile up. Shortly, it will
significantly impact people’s way of living and, worse, people’s health.
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Background and Applications of Pyrus pyrifolia Components
Asian pear is a fruit native to East Asia, commonly known as apple pear due to its
striking similarities with an apple. In terms of mineral compositions such as; zinc, copper,
calcium, magnesium, phosphorus, potassium, and sodium. Pears have the advantage, but
in terms of flexibility and usage, apples tend to have more uses in the field of research
due to their high composition of vitamins (Movsisyan, 2020). Undeniably, we can not
ignore the fact that pears contain more fiber than apples, and one usage is paper. The
cellulose fibers in wood, fiber crops, and paper waste are separated chemically or
mechanically to create pulp, a lignocellulosic fibrous material. Pulp is the primary raw
material used in papermaking and the industrial production of other products, mixed with
water and additional chemical or plant-based additives.
Pears and apples have similar compositional structures that are exceptional for
epidemiological investigations. Pears stand out from other fruits due to their high dietary
fiber content and positive benefits on gut health (Reiland & Slavin, 2015). As a result, it
makes them a better component of research. A great source of dietary fiber and a rich
source of vitamin C is pears. According to Reiland & Slavin (2015), this type of dietary
fiber also functions as an antioxidant and has been reported to be contained in pears. The
dietary fiber in pears can be drawn upon to make cellulose. Earth-based biomaterials,
notably pear peel, are used to make fiber. used for their dietary fiber and advantageous
health effects. (Reiland & Slavin, 2015). The primary component of plant cell walls is
cellulose, which aids in the ability to maintain stiffness and strength. Although cellulose
is indigestible to humans, it provides a significant source of fiber. People regularly
employ pear skins to help their bodies' digestive systems. But its composition is more
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potent than apples making it a better subject for research. Pears also have a lot of dietary
fiber in fruits, especially young fruits.
According to Eun et al. (2012), insoluble dietary fiber decreased, and soluble
dietary fiber increased according to the growth of pear fruits. Since it can have an impact
on the final product's quality, the maturity age is taken into account. The peel has more
dietary insoluble fiber when harvested. However, the soluble fiber in the pulp
outnumbered the insoluble fiber. The peel's insoluble dietary fiber level is greater during
harvest. But in the pulp, soluble fiber outnumbered insoluble fiber. The pulp is necessary
as it is the compound prepared by chemical or mechanical means from various materials
in making paper and cellulose products. For the researchers, this study will be beneficial
since it will give an idea if the leftover pear waste is recyclable or not Different tactics,
including freezing, are also possible. During freezing, enzyme activity is slowed, and the
substances that aid the plant's ripening and maturing are present in all fresh produce
(Food Preservation: Freezing Basics, 2016). Frozen fruits and vegetables at 0 degrees
Fahrenheit to ensure the highest quality.
Components and Application of Red Cabbage
Red cabbage, scientifically known as Brassica oleracea, is also called blue kraut,
purple cabbage, or red kraut (Sylvia, 2019). It is a nutrient-rich, cruciferous, or Brassica
vegetable related to cauliflower and kale (WebMD Editorial Contributors, 2022). It is a
multi-layered vegetable from the Brassicaceae family and Brassica genus and is closely
linked to broccoli, brussels sprouts and cauliflower, and savoy cabbage. The cabbage has
dark red/purple leaves that typically change color according to the pH value of the soil.
This rich red color of red cabbage is due to anthocyanin polyphenols (Sylvia, 2019).
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Anthocyanins are a subgroup of flavonoids. Therefore, they are polyphenols responsible
for giving plants their distinctive colors. These pigments are soluble in water (Admin,
2019).
Over a century has passed since red cabbage was first used to make litmus paper.
In the 17th century, scientist Robert Boyle wrote about using red cabbage as a pH
indicator. The anthocyanin pigments in red cabbage alter hue depending on whether
immersed in an acidic or alkaline solution. Because of their sensitivity to pH, the
pigments' colors can change from red to blue or green (Chang et al., 2011). Due to its
ability to serve as a reliable pH indicator, red cabbage has become a common ingredient
in homemade litmus paper. Litmus paper determines whether a given solution is acidic or
basic. It finds widespread application in academic, scientific, and medical settings. The
paper has a pH-sensitive dye infused, so the color shifts as the pH level does. Since it is
inexpensive, abundant, and simple to process, litmus paper made from red cabbage is
popular (Joshi & Gupta, 2016).
The red cabbage used to make the litmus paper is boiled for 30 minutes in water,
strained, and then cooled. Litmus paper combines the resulting liquid with filter paper,
soaking it up and dries it (Munir & Farooq, 2014). The resulting litmus paper can be
preserved indefinitely and kept dry. There are benefits to using red cabbage-based litmus
paper instead of synthetic litmus paper. For starters, it is a healthy substitution for
synthetic dyes. The second benefit is that it is eco-friendly because it uses sustainable
materials. Third, it decomposes naturally and can be discarded without harming the
environment (Chang et al., 2011).
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In conclusion, red cabbage is a widely used and highly reliable natural pH
indicator that can be incorporated into litmus paper. Because of the anthocyanin pigments
it contains, its color shifts in response to increases or decreases in acidity or alkalinity.
Instead of using synthetic litmus paper, which can harm the environment, red
cabbage-based litmus paper is a better alternative.
Methods of Extracting Fibers and Cellulose
Extraction is the process in which there is a separation among different
components in a variable. An example would be extracting a nail from a piece of wood.
However, in science, extraction involves employing a solvent to remove the desired
ingredient from a mixture. The compound must be more soluble in the solvent than inside
the mixture for an extraction to be successful. The solvent and combination must also be
immiscible. One of the variables is P. pyrifolia, a fruit with a high quantity of fiber.
According to Amezquita et al. (2018), “The Weende method with an acid and an alkali
extraction quantified the sum of cellulose and lignin as crude fiber.” This method uses
sequential acid and alkali extractions that remove the protein, sugar, starch, lipids, and
portions of structural carbohydrates and lignin inside a compound. The fiber is removed
from the fruits and vegetables, making the fiber extraction more accessible.
Another process used is the mechanical processing of bast fibrous plants, where
the maximum amount of fiber is extracted to the highest possible quality to allow further
processing. However, compared to bast fiber obtained through retting, the quality of the
bast fiber obtained using this approach could be better. Decorticated fibers are highly
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polluted with the remains of other plant tissues and are thick, robust, non-divisible, and
ornamental (Kumar & Suganya, 2017).
Squeezing and breaking are mechanical processing techniques that separate fiber
from woody components. Whether present in a greater or lesser amount, the stress that
raw materials experience during stretching may result in fiber damage or breaking. It may
have a direct negative impact on the quality (Kumar & Suganya, 2017). The degree of
mechanical processing may cause the fiber to be excessively shortened and thoroughly
purified. Though this process may be inefficient in terms of quality, to counteract its
inefficiency, stem moisture needs to be maintained between 10 and 11% for the best
capacity of both scutched and hackled fibers to optimize scutched fiber divisibility. This
process is executed to counteract and decrease the direct influence that passing through
the mechanical process has on quality.
Other Pear-Related Products
Pears have significantly contributed to our society, including the food industry,
beauty products, and health. Unsurprisingly, pears are used in the food industry, whether
savory or sweet. It is consumed raw or cooked, peeled or unpeeled. Examples are; salads,
sauces, jams, pastries, and beverages such as juice, smoothies, or wine. Pears are also
used in desserts. They make excellent toppings, garnishes, sauces, and side dishes for
savory dishes.
Similarly, pears have outperformed beauty products because they contain
nutrients that help maintain the skin's PH balance. Lactic acid, found in pears, keeps your
skin smooth. Pear enzymes help skin cells turn over more frequently (Hatcher, 2015).
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Some examples are soaps, face masks, bath gel, sugar scrubs, etc. Furthermore, pears are
essential for our health. The antioxidants present in them improve immunity and combat
many health ailments. They contain many beneficial nutrients and minerals (Choudhary,
2022). Pears' health benefits include the ability to control blood sugar levels, boost the
immune system, aid in blood pressure control, and prevent heart disease due to the
presence of fiber, which reduces the risk of stroke, among other things. Pears also contain
many other nutritional ingredients, particularly minerals, vitamins, and fiber, which are
the strengths of this juicy fruit.
Additional Components to Increase the Durability of Paper
Traditional food packaging has been around for years and have gone through
many processes. Despite being made out of paper, it has evolved a wide range of sizes
and storage capacities, as well as the durability of holding a large number of items. They
are made from wood, and the most popular material for paper food packaging is Kraft
paper, which is manufactured from wood chips (Mart, 2020). Since they are made from
paper, their raw material, a cellulose fiber extracted from wood, is the reason for the
durability and structure of the packaging.
These food packaging could not be made without paper because it was in its
original form before being transformed into a food packaging. Paper is a thin sheet
usually manufactured from cellulose pulp derived from wood and other lignocellulosic
materials such as cotton, rice, or wheat straw for writing, printing, and packaging
purposes (Hiziroglu, 2016). Just like paper food packaging, paper is made in two steps;
cellulose fibers are extracted from a variety of sources and converted to a pulp, combined
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with water, and placed on a paper-making machine where it is flattened, dried, and cut
into sheets and rolls (Casey, 2017).
Paper pulp is formed in papermaking from wood pulp or plant fiber, the raw
material of paper that strengthens its durability. As a result, the paper-making pulp can be
manufactured by machine, chemically, or by hand. Pulp is prepared from machines either
mechanically or chemically. The mechanical method (generally used to make lower
grades of paper) is called the groundwood process because the pulp was originally made
using huge stones to grind up logs. Nowadays, pulp is prepared by giant machines that
cut, wash, chop, beat, and blend wood, rags, or other raw materials into a soggy mass of
fibers. In the chemical method, known as the Kraft process (from the German word for
"strength" because it produces strong paper), plant materials are boiled up in solid alkalis
such as sodium sulfide or sodium hydroxide to produce fibers. At this point, loading
materials (surface coatings such as clays), dyes (to make colored paper), and sizes (to
strengthen and waterproof and prevent inks from spreading) can be added to the mixture
to change the properties of the finished paper (sometimes they're added later). On the
other hand, paper made by hand uses raw plant material placed in a large vessel filled
with water and beaten to a pulp to make a thick suspension of fibers called half-stuff.
This is formed into sheets of paper using a basic frame made of two parts: a metal mesh
called a mold that sits inside a wooden frame known as a deckle (Woodford, 2021).
Aside from the various manufacturing processes, one of the most important
aspects of paper food packaging is their durability. Because it is primarily made of paper,
fiber is one of the additional components used to increase the durability of the paper
packaging. A high percentage of fiber derived from plants, vegetables, or fruits can
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improve the durability of paper pulp. Because all plants' cell walls contain cellulose
fibers, an organic material known to chemists as a linear polysaccharide. It constitutes
about one-third of the structural material of annual plants and one-half that of perennial
plants. Cellulose fibers have high strength and durability. They are readily wetted by
water, exhibiting considerable swelling when saturated, and are hygroscopic; they absorb
appreciable amounts of water when exposed to the atmosphere. Even in the wet state,
natural cellulose fibers show no loss in strength. It is the combination of these qualities
with strength and flexibility that makes cellulose of unique value for paper manufacture.
Most plant materials also contain non-fibrous elements or cells found in pulp and
paper. The non-fibrous cells are less desirable for papermaking than fibers but, mixed
with fiber, are of value in filling in the sheet. Paper can be produced from any natural
plant (Britt, 2020). Other than fibers, chemical components like agents or additives could
also help strengthen the paper. For example, Carboxymethyl Cellulose CMC is an
effective papermaking additive. It can be used in many procedures such as pigment
coating, adding in the pulp and surface sizing, with good water-retaining properties,
dispersibility, and shear thinning ("Carboxymethyl Cellulose Paper Grade", n.d.). Wet
strength additives ensure that it retains its strength when the paper becomes wet. This is
especially important in tissue paper. Typical chemicals used are epichlorohydrin,
melamine, urea formaldehyde, and polyamines. These substances polymerize in the paper
and result in the construction of a strengthening bond. Dry strength additives, also known
as dry strengthening agents, are chemicals that improve paper strength in normal or not
wet conditions. Those strengths include compression strength, bursting strength, tensile
breaking strength, delamination resistance, etc. Typical chemicals used are cationic starch
24
and polyacrylamide (PAM) deliveries. These Dry strength additives act as binders of
fibers, often under the aid of aluminum ions in paper sheets. Cationic starch enhances the
paper's strength, and cationic starch is added to the wet pulp in the manufacturing process
(Pulp and Paper 52Technology, 2022).
Components and Uses of Methanol
Methanol, also called methyl alcohol, wood alcohol, or wood spirit with the
chemical formula of CH3OH, is the simplest of a long series of organic compounds
called alcohols, consisting of a methyl group (CH3) linked with a hydroxyl group (OH)
(The Editors of Encyclopaedia Britannica, 2023). This chemical has been used and found
in various household and industrial agents and the production of various other chemicals.
It is also primarily used as an industrial solvent, a manufacturing process, or a fuel.
Despite its applications and importance in modern technology, this colorless liquid
chemical is highly toxic and dangerous.
Methanol is a toxic alcohol, the term “toxic alcohols” is a collective term that
includes methanol, ethylene glycol, and isopropyl alcohol. The toxicity of this chemical
can lead to various health risks; examples are methanol poisoning is most often due to
accidental or intentional ingestions, and accidental epidemic poisonings due to distilling
and fermenting errors and beverage contamination. Exposures can cause varying toxicity
and require various treatments, from close laboratory monitoring to antidotal therapy and
dialysis. Lastly, methanol toxicity can occur via ingestion, dermal absorption, and
inhalation (Ashurst, 2022). Methanol is an essential solvent in many scientific disciplines
25
and has many other practical uses. Because of its high purity, low price, and functional
physical properties, it is widely used in various scientific studies.
Methanol is an essential solvent in many scientific disciplines and has many other
practical uses. Because of its high purity, low price, and functional physical properties, it
is widely used in various scientific studies.
Methanol is a common solvent used in the chemistry industry to produce and
purify a wide range of chemical compounds. Methanol was an effective solvent for the
electrochemical synthesis and purification of various compounds in a study conducted by
Amatore et al. (2017). The synthesis of nanoparticles and thin films are two examples of
methanol's applications in materials science. Silver nanoparticles of uniform size and
shape were synthesized using methanol as the reducing agent, according to research by
Elumalai et al. (2018). Methanol is a valuable research tool only if its potential dangers
and storage protocols are adequately considered. Several studies have stressed the
significance of adequate ventilation, labeling, and storage in reducing the risk of fire,
explosion, and toxicity when working with methanol (Dixon & Harrison, 2018; Zhang et
al., 2021).
FTIR Analysis of Different Cellulose Samples
The Fourier Transform Infrared Spectroscopy (FTIR) is a standard analytical
method for determining a sample's chemical makeup from its infrared spectra—the FTIR
spectrum of different cellulose samples. FTIR spectroscopy has been used in numerous
researches to probe different paper properties. Filter paper made from various cellulose
fiber sources was analyzed for its chemical composition using FTIR spectroscopy in a
26
study by Jabeen et al. (2013). Filter paper made from various cellulose fiber sources had
similar FTIR spectra, suggesting that this technique could not distinguish between them.
The filter paper's chemical and physical properties after gamma irradiation were studied
using Fourier transform infrared spectroscopy. The peak intensities and positions of the
FTIR spectra of gamma-irradiated filter paper were found to change, indicating a change
in the filter paper's chemical composition.
Research into the thermal stability of biopolymers and their composites, such as
the Kinetic Thermal Degradation of Cellulose, Polybutylene Succinate, and a Green
Composite, has aided our understanding of these materials. Using thermogravimetric
analysis (TGA) and differential scanning calorimetry, the researchers looked into what
happened to cellulose, polybutylene succinate (PBS), and a green composite made from
the two materials when exposed to heat (DSC). The study found that the thermal stability
of the green composite was greater than that of cellulose and PBS separately.
Under a nitrogen atmosphere and at constant nominal heating rates of 5, 10, and
15 °C/min, the kinetics of thermal degradation were studied for cellulose, polybutylene
succinate, and a physical blend of both polymers (cellulose (80%) + PBS (20%)) and
compared with commercial polycaprolactone by dynamic thermogravimetry. Related
studies show the potential of natural fillers in increasing the thermal stability of
biopolymers and their composites. The results of the study Kinetic Thermal Degradation
of Cellulose, Polybutylene Succinate, and a Green Composite are consistent with these
findings.
Paper made from various agro-based fibers was analyzed for chemical
composition and quality using FTIR and UV-Vis DRS spectroscopy (Suresh et al., 2016).
27
They discovered that the chemical composition and quality of paper made from various
agro-based fibers varied, as evidenced by differences in the peak positions and intensities
in the FTIR and UV-Vis DRS spectra. Paper and papermaking raw materials can be
analyzed for their chemical composition and quality with FTIR and UV-Vis DRS
spectroscopy, which have proven to be practical analytical techniques. Paper's properties
and performance in different contexts can be affected by its chemical composition and the
quality of the raw materials used in its production, as shown by these studies.
Conclusion
In conclusion, the related literature and studies provide a general overview of the
research. The researchers have critically assessed and evaluated the associated studies to
establish a framework for what is understood or known about P. pyrifolia and
Carboxymethyl Cellulose used in making paper food packaging. The six sub-topics in the
review of related literature provide all the necessary information, such as the problems
caused by papermaking and its effects on the environment, the annual pear and fruit
waste problem, the components of P. pyrifolia, the methods of extracting the fiber and
cellulose, and finally, other pear-related products. This part of the research demonstrates
the feasibility of the study. It offers guidance on how to proceed and whether it will be
possible for the researchers to produce a product from P. pyrifolia waste and
Carboxymethyl Cellulose. Although numerous researchers have conducted studies on the
topic, none of the existing studies have mainly discussed the ability of P. pyrifolia wastes
and carboxymethyl cellulose to be manufactured into quality paper food packaging. This
research gap has encouraged researchers to conduct experiments to test the strength of P.
pyrifolia fibers and, in addition, carboxymethyl cellulose. No other study has attempted
28
to use P. pyrifolia fibers to create paper. The researchers will use the existing studies and
the data gathered from the experimentation to determine the ability of P. pyrifolia and
Carboxymethyl Cellulose to make paper food packaging.
29
Conceptual Framework
The conceptual framework of this study connects the relationship of the variables
used. In the research, the amount of Pyrus pyrifolia and carboxymethyl cellulose needed
is the independent variable, and the quality of the paper food packaging is the dependent
variable. The research paradigm used in this study is an I.P.O format, also known as the
input, process, and output. This is to help the researchers identify the study's possible
results and explain the variables' relationships to solidify the researchers’ basis further.
Figure 1. Conceptual Paradigm
(Main Variables of the Study)
The research paradigm contains the input, process, and output. The different
independent variables to be manipulated, used, and tested by the researchers are within
the input. These independent variables are the P. pyrifolia Waste, specifically its fiber
content, and carboxymethyl cellulose. This research focuses on the amount of P. pyrifolia
30
waste as the main component in creating the food packaging as its peel contains a high
amount of fiber, while carboxymethyl cellulose is used as a way to strengthen and bind
the fibers together.
The study's process will begin with the preparation of the materials needed for the
second step, which is the production of the paper food packaging made of P. pyrifolia.
After producing the paper packaging, the researchers will proceed with the tests to
measure the quality. These tests are namely a.) FTIR Analysis Result, b.) Stripping
Quality/Weight Capacity, c.) Methanol Test Result (Flammability test), d.) Effectiveness
of Anthocyanin in Color Alteration
Following these will be the evaluation of the results of the tests. After this, the
researchers will revise and remake the food packaging until they can produce their
desired product. Lastly, the output, the research anticipates yielding high-quality food
packaging constructed of P. pyrifolia and carboxymethyl cellulose. The aforementioned
tests are all used to determine the quality of the food packaging made from P. pyrifolia
and carboxymethyl cellulose.
31
Definition of Terms
The following terms used in the study are conceptually and operationally defined
to give the reader a better understanding of the research.
Carboxymethyl Cellulose. Conceptual definition: It is also known as cellulose
gum and is a cellulose derivative with carboxymethyl groups (-CH2-COOH) bound to
some of the hydroxyl groups of the glucopyranose monomers that make up the cellulose
backbone.
Operational definition: a widely used co-binder and modifier in paper coating
used in the pulp-making process to enhance paper's durability and strength.
Brassica Oleracea. Brassica oleracea, also known as wild cabbage, is a plant
species that belongs to the family Brassicaceae. It is known to contain a significant
amount of anthocyanin and therefore commonly used in the creation of litmus paper.
Fiber. A fine thread made of a natural or synthetic material, particularly one used
to create cloth or rope.
Packaging. These are containers, sometimes made of paper which are mostly
made out of pulp from wood fibers and are commonly used to contain food.
Papermaking. The process of creating paper by forming a matted or felted sheet
from a water suspension on a wire screen.
Pulp. A fibrous lignocellulosic material created by chemically or mechanically
removing the cellulose fibers from materials including wood, waste paper, rags, and fiber
crops.
32
Pyrus pyrifolia. It is also known as the Asian Pear, a species of pear tree rich in
fiber and native to East Asia.
Waste. is an unwanted and unusable material and is regarded as a substance
which is of no use.
33
CHAPTER 3
METHODOLOGY
The methodological approach, methodology framework, procurement of
materials, data gathering, and data analysis to be used in the current study are all
covered in this chapter.
Methodological Approach
This study tackles Pyrus pyrifolia waste, carboxymethyl cellulose, and Brassica
oleracea L. var. capitata f, rubra (Red Cabbage) to manufacture food packaging. The
study aims to address the problem of the excessive amount of fruit waste negatively
affecting the environment causing pollution and global warming. The study is an
experimental type of research in which the goal is to create durable food packaging using
P. pyrifolia, carboxymethyl cellulose, and B. oleracea L. var. capitata f, rubra (Red
Cabbage). Planning a series of methods to examine a link between variables is known as
experimental design. to create a well-controlled test (Bevans, 2019)
The research would use a quantitative method that measures values and data
expressed in numerical value. This is to verify if P. pyrifolia, B. oleracea L. var. capitata
f, rubra (Red Cabbage), and carboxymethyl cellulose are effective components in
creating food packaging to reduce food waste through statistical analysis. The
posttest-only control group and the ONE-WAY Anova will be applied in the research to
obtain the statistics needed. Tests such as; FTIR Spectroscopy, methanol testing, weight
capacity, and PH tests are used to obtain the necessary data, which will be further
explained in this chapter.
34
Methodological Framework
Figure 2: Methodological Framework.
35
Procurement of Materials
This part of the study contains the materials that the researchers need to conduct
the study, what they are, and how they will be acquired.
1. Materials for Production
The following are the materials that are needed to produce the food
packaging. These materials will either be acquired, bought, made, or extracted by
the researchers themselves.
1.1. Carboxymethyl Cellulose (CMC)
Carboxymethyl cellulose or CMC is a cellulose gum used in the
pulp-making process and paper coating that will help enhance the food
packaging's durability and strength by improving the bond of pulp fibers.
Carboxymethyl Cellulose will be bought by the researchers from a local
pharmacy.
1.2. Blender
A blender helps crush pear wastes into smaller particles faster when
mixed with ample water. Blenders are also more efficient when manually
making paper, as they can help blend more pulp at once. The blender will be
acquired from the researchers’ available equipment.
1.3. Deckle and Mold
36
A deckle is a removable wooden frame used to shape and limit the size
of a sheet by hand. It is done by being dipped in the water together with the
mold, then shaken to drain excess water off. This will be used to create the P.
pyrifolia paper for the food packaging. This will be bought by the researchers
from the National Bookstore.
1.4. Steam Distillation Apparatus
This apparatus was made from scratch by the researchers using
laboratory equipment like glass pipes, round bottom flasks, Bunsen burners, a
condenser, a magnetic stirrer, a hot plate, and a conical flask. This apparatus
will be used to separate the methanol from the Red Cabbage and Methanol
solution
2. Materials for Testing
These materials will be acquired by the researchers and through the help
of the Department of Science and Technology laboratories.
2.1. FTIR Analysis
The Fourier Transform Infrared is a piece of equipment needed to
conduct analyses on specimen composition. This device uses infrared light to
scan test samples and observe the chemical properties of the food packaging
to be made by the researchers. The researchers will use equipment provided
by the laboratory of DOST.
2.2. Weights
37
These will be used to measure the stripping quality or the weight
capacity of the food packaging. The researchers will measure how much
weight the packaging can be subjected to until it breaks. The researchers will
be the ones to provide the weights.
2.3. Acids, Bases, and Food and Litmus Paper
Acids and bases will initially be used to test the pigment-changing
property of the food packaging. The litmus paper will be used to compare the
results of the tests. Subsequently, food that is at different degrees of spoiled
will need to be used to test whether the Litmus paper-like properties of the
packaging are effective and are accurately working. This will ensure that the
food packaging will correctly alert the users of the state of their food.
Data Gathering Procedures
The study will be completed through a series of experiments. It starts with the
extraction of anthocyanin using the steam distillation extraction method, to the manual
manufacturing of food packaging from P. pyrifolia pulp, adding the CMC as a binder, and
applying the Brassica oleracea L. var. capitata f, rubra (Red Cabbage) extracts onto the
paper. The quality of the product will then be examined through various testing
procedures such as FTIR analysis, methanol testing, stripping quality testing, and the
effectiveness of anthocyanin through its color alteration.
1. Preparation of Materials
38
This is the process of preparing the necessary raw materials and
equipment for the experiment, which include Pyrus pyrifolia (Asian pear) waste,
Brassica oleracea L. var. capitata f, rubra (Red Cabbage), Carboxymethyl
cellulose (CMC), a deckle, a blender, and a steam distillation apparatus.
1.2. Anthocyanin Extraction
The researchers will use a magnetic stirrer to mix the Red Cabbage strips
with the methanol. Afterward, using the steam distillation process, the researchers
will remove the methanol from the mixture for the anthocyanin extracts to remain
(Cerpa et al., 2008). To verify whether it was methanol that was extracted from
the mixture a methanol test will be conducted.
2. Food Packaging Production
This procedure describes the process of making food packaging, namely;
pulp making, pulp and cellulose mixing, deckle and mold, anthocyanin
application, and packaging production (Rosalina, et. al., 2021).
2.1. Pulp Making
Pulp making is the process of producing individual fibers from raw
materials that have been washed, cooked, and blended. The P. pyrifolia waste
will be taken from the researchers’ source and will be washed, cooked, and
then blended in a blender to produce the pulp required for the papermaking
process (Davidsdottir, 2013). ‌.
2.2. Pulp and Cellulose Mixing
39
After creating the P. pyrifolia pulp and carboxymethyl cellulose are
mixed to make the paper to enhance the durability and strength of the food
packaging. This mixture will serve as the main ingredient for the packaging
combined with the additional ingredients.
2.3. Deckle and Mold
A deckle is a wooden frame tool used in papermaking to shape the
pulp when making paper by hand. In this process, the pulp fibers are washed
and screened to remove any remaining fiber bundles. Subsequently, the water
is then pressed out, and the residue is dried, creating the P. pyrifolia and
CMC paper.
2.4. Anthocyanin Application
The pre-made anthocyanin shall then be applied to the paper to
help recognize whether food has gone bad. In this step, the researchers will
brush the anthocyanin extract directly onto the paper and test it to see its
effectiveness. In the case of lactic acid production, the addition of
anthocyanins to food packaging could be used to monitor the growth of
spoilage microorganisms in a fermentation process. As the pH of the
fermentation environment changes due to the growth of unwanted
microorganisms, the color of the packaging will change, indicating that the
fermentation process has been compromised and the product may no longer
be safe to consume.
2.5. Packaging Production
40
After producing the paper, the researchers will then proceed with
creating the final product, which is the food packaging. The paper will be
taken from the drying process and will then be folded into the structure of the
packaging. With this, the product is completed and will then be subjected to
numerous testing to ensure the quality made.
3.
Laboratory Testing
Laboratory testing is a process that is carried out with careful statistical
analysis, quality standards, and close supervision. The researchers will conduct
lab testing regarding the FTIR Analysis, Methanol Testing, Stripping Quality, and
PH Test of the food packaging to gather accurate and reliable results on how
durable Pyrus pyrifolia, Brassica oleracea L. var. capitata f, rubra (Red
Cabbage), and carboxymethyl cellulose (CMC) food packaging is.
3.1. FTIR Analysis
Fourier Transform Infrared Spectroscopy or FTIR Spectroscopy is an
analytical method used to distinguish between organic, polymeric, and,
occasionally, inorganic materials. The FTIR analysis method scans test
materials and examines chemical characteristics using infrared light (RTI,
2015). The device will be scanning the chemical properties of the food
packaging to ensure the quality of the product.
3.2. Methanol Testing
41
Methanol testing will be conducted to verify that it was methanol
extracted from the solution using the steam distillation method. The
verification of methanol ensures that the anthocyanin extracts are not toxic
when applied to the food packaging. The researchers will create an apparatus
to test the presence of methanol.
3.3. Testing for Stripping Quality
To test the stripping quality of the food packaging or the weight that it
can withstand before it rips. The researchers will subject the packaging to
different levels of weight to test its maximum weight capacity. The stripping
quality will be measured by the mass of the weight that caused the packaging
to break.
3.4. PH Test
The researchers will use acids, bases, and different degrees of spoiled
food to determine whether the litmus paper-like color-changing properties of
the food packaging is effective and accurate. Subsequently, the researchers
will compare the color changes with the actual Litmus paper (Helmenstine,
2020). The test will see whether the packaging correctly changes its color
based on the acid, base, or food it is subjected to.
Data Processing
This study was conducted with the goal to answer the following questions to
reach a conclusion on the ability of Pyrus pyrifolia (Asian Pear), Brassica oleracea L.
42
var. capitata f, rubra (Red Cabbage), and carboxymethyl cellulose to produce food
packaging that can not only efficiently protect the food inside but also accurately inform
the users of the quality and freshness of food. To be able to quantitatively assess the data
gathered from the study and use them to answer the aforementioned questions, The
one-way Anova shall be put into use by the researchers.
Statistical Treatment of Data
The data collected in the study contains the result and observation of the testing of
Pyrus pyrifolia, Brassica oleracea L. var. capitata f, rubra (Red Cabbage), and
carboxymethyl cellulose-made food packaging. The observation and testing are done
through lab investigation using different equipment such as; FTIR analysis, Methanol
Test, Stripping quality test, and tests for the effectiveness of Anthocyanin in color
alteration. It provides accurate and reliable data regarding the packaging’s composition,
weight capacity, and color-changing accuracy in comparison to standard food packaging.
The data collected from this analysis serves as a guideline for the characteristics of the P.
pyrifolia food packaging.
The researchers employed the one-way ANOVA to evaluate the data. In
determining the significant differences between the different lab results, a one-way
analysis of variance (ANOVA) is performed to test the claim (Heiberger & Neuwirth,
2009). With this, the one-way ANOVA will study the difference in the scores of each lab
test. Scores (X) of each group will be identified and graded as follows:
1.
Paper quality
a. Very Brittle - 1
43
b. Somewhat Brittle - 2
c. Barely Brittle - 3
d. Not Brittle - 100
2.
Reaction scale of Anthocyanin and Paper
a. Does not react with Acids and Bases -1
b. Slightly reacts with Acids and bases - 2
c. Reacts with Acids and Bases - 3
d. Strongly reacts with acids and bases -4
3.
Quality of food packaging
3.1.
FTIR Analysis
a. Weak Cellulose Bonds, Stretches, and Vibrations - 1
b. Moderate Cellulose Bonds, Stretches and Vibrations - 2
c. Strong Cellulose Bonds, Stretches and Vibrations - 3
d. Very Strong Cellulose Bonds, Stretches and Vibrations - 4
3.2.
Stripping Quality/Weight Capacity (Pounds)
a. 2 kilograms - 1
b. 3 kilograms - 2
44
c. 4 kilograms - 3
d. 5 kilograms - 4
3.3.
Effectiveness of Anthocyanin in Color Alteration
a. 25% Accuracy - 1
b. 50% Accuracy - 2
c. 75% Accuracy - 3
d. 100% Accuracy - 4
Steps in One-Way ANOVA
According to Zach (2020), there are 6 steps in using One-way ANOVA which are
as follows:
1. The Mean (x̄) of the three scores will be computed and used for the One-way
ANOVA. Furthermore, the overall mean of the two groups will also be computed.
2. Sum of Squares Regression (SSR)
3. Sum of Squares Error (SSE)
4. Sum of Squares Total (SST)
5. ANOVA Table
6. Interpretation.
45
CHAPTER 4
PRESENTATION, ANALYSIS, AND INTERPRETATION OF DATA
Introduction
This part of the research paper tackles the culmination of the study. Thus, it will
show the highest point, the results and discoveries after the study's experimentation. To
be seen in this part are the researchers' findings about manufacturing food packaging
using Pyrus pyrifolia (Asian Pear) wastes with the help of Carboxymethyl cellulose or
CMC and Brassica Oleracea (Red Cabbage). This chapter aims to provide the product of
the analytic process and to present the analysis and interpretation of data gathered from
the study, and to give an answer to the following research questions;
1. How much Pyrus pyrifolia waste, Brassica oleracea extracts, and carboxymethyl
cellulose is needed to manufacture a single food packaging?
2. What concentration of B. oleracea extracts is needed to accurately determine food
spoilage?
3. What is the difference between the quality of food packaging made of P. pyrifolia
wastes, Brassica oleracea extracts, and carboxymethyl cellulose and conventional
food packaging in terms of the following:
a. FTIR Analysis Result
b. Stripping Quality
c. Effectiveness of color-alteration
46
Results
Creation of Anthocyanin
For the researchers to proceed with the experimentation, they must first
create an anthocyanin extract from red cabbage to be applied to the paper for its
color alteration purposes and to achieve its primary goal of the paper reacting to
different types of pH levels that resulted from expired food. After the researchers
extracted the methanol from the anthocyanin solution, they verified if the
extracted substance was methanol by doing a flammability test. A blue, clean
flame indicates that the substance is methanol. The substance was found to be
flammable, confirming the scientists' suspicion that the product of the steamed
distillation was methanol.
Reaction Scale of Paper Made from Pyrus Pyrifolia and Anthocyanin with
Different Acids and Bases.
After the researchers have successfully applied the anthocyanin solution to
the paper, they will now conduct the pH test to determine the reaction scale of the
paper made from P. pyrifolia and anthocyanin and how it reacts with different
substances. This test will determine how effective and accurate the anthocyanin is
in reacting with different acids and bases; the results shown below are the
different types of substances used and how it reacted with the Litmus paper and
the paper made from P. pyrifolia and anthocyanin.
47
Table 1. Effectiveness of anthocyanin pH test with different concentration levels
Comparing the pH test results between Sample 1 (50% Water, 50%
Methanol) and Sample 2 (100% Methanol) for various substances, it is found that
most substances showed accurate pH level changes. However, some differences
were observed. Lime displayed slightly lower acidity in Sample 2, while turmeric,
vinegar, and baking soda had consistent pH levels in both samples. Although the
pH test was reliable, Sample 2 had more deviations from the original pH values
than Sample 1. To ensure safety and maintain effectiveness in extracting
anthocyanin, the researchers will use the 50% water and 50% methanol solution.
This solution yields the same results as 100% methanol but is safer due to reduced
flammability and toxicity. Diluting methanol with water minimizes risks
associated with pure methanol handling, providing a practical and manageable
solution for safe extraction while achieving successful anthocyanin extraction.
FTIR Spectroscopy Analysis
FTIR
spectroscopy
was used to identify functional groups in
cellulose-based paper derived from Pyrus pyrifolia wastes and carboxymethyl
cellulose. The analysis revealed abundant hydroxyl groups, aliphatic chains, and
ester linkages in carboxymethyl cellulose. Bending modes and stretches were
observed, including C-H bending, aliphatic C-H bond bending, and ester linkage
48
stretching. Water, aromatic aryls, alkanes, alcohols, and ethers were also detected.
These results provide valuable insights into the paper's properties, including
durability, stiffness, water absorption capacity, and potential applications. The
FTIR spectroscopy analysis confirms the presence of different functional groups
and
vibrations, supporting the
effectiveness and traditional paper-like
characteristics of the Pyrus pyrifolia and carboxymethyl cellulose-based paper for
paper production.
Stripping Quality
In testing for the stripping quality the researchers filled bottles with water
from 2 kilograms up to 5 kilograms, and then placing them on top of the paper
without anything to support the weight.. The test is capped at 5 kg as the food to
be carried by the packaging will not exceed this weight. The paper was able to
undergo through all 4 tests, from 2 kg up to 5 kg giving it a score of 4 on the
results for stripping quality. On the other hand, a regular piece of paper had ripped
at 3 kg giving only a score of 2.
One-Way ANOVA
The researchers employed one-way ANOVA to evaluate the data. In
determining the significant differences between the different lab results, a
one-way analysis of variance (ANOVA) is performed to test the claim (Heiberger
& Neuwirth, 2009). With this, the one-way ANOVA will study the difference in
the scores of each lab test. Scores (X) of each group are identified and graded as
follows:
49
1.
Paper quality
a. P. pyrifolia, Carboxymethyl Cellulose, and B. oleracea food
packaging - 3 (Somewhat brittle)
b. Standard food packaging - 4 (Not brittle)
2.
Reaction scale of Anthocyanin and Paper
a. P. pyrifolia, Carboxymethyl Cellulose, and B. oleracea food
packaging - 4 (Strongly reacts with acids and bases)
b. Standard food packaging - 1 (Does not react with acids and bases)
3.
Quality of Food Packaging
3.1.
FTIR Analysis
a. P. pyrifolia, Carboxymethyl Cellulose, and B. oleracea food
packaging - 4 (Very Strong Cellulose Bonds, Stretches and
Vibrations)
b. Standard food packaging - 3 (Strong Cellulose Bonds, Stretches
and Vibrations)
3.2.
Stripping Quality/Weight Capacity (Kilograms)
a. P. pyrifolia, Carboxymethyl Cellulose, and B. oleracea food
packaging - 4 (5 Kilograms and more)
b. Standard food packaging - 2 (3 Kilograms)
50
3.3.
Effectiveness of Anthocyanin in Color Alteration
a. P. pyrifolia, Carboxymethyl Cellulose, and B. oleracea food
packaging - 3 (75% Accuracy)
b. Standard food packaging - 1 (Less than 25% Accuracy)
Table 2. ANOVA Data Scoresheet
Test
P. pyrifolia, CMC, and
Standard food
B. oleracea food
packaging (SFP)
packaging (PFP)
Paper Quality
3
4
Reaction scale of
4
1
FTIR Analysis
4
3
Stripping Quality
4
2
Effectiveness of
3
1
18
11
Anthocyanin and Paper
Anthocyanin in Color
Alteration
∑x
51
F Statistic for One-Way Anova is 8.54. Using the F distribution table and
the following values:
1.
α (Significance level) = 0.05
2.
DF1 (df Treatment) = 1
3.
DF2 (df Error) = 8
It is found that the F critical value is 5.3177. Since the F statistic in the
ANOVA table is greater than the critical value in the F distribution table, we reject
the null hypothesis. Thus, the study has enough evidence to confirm that P.
pyrifolia, Carboxymethyl Cellulose, and B. oleracea food packaging are better
quality than standard food packaging. Furthermore, this concludes that Pyrus
pyrifolia (Asian Pear), Brassica oleracea L. var. capitata f, rubra (Red Cabbage),
and carboxymethyl cellulose can be used to manufacture food packaging that
possesses exceptional durability and toughness.
Discussion
The anthocyanin's efficacy in changing colors was evaluated by placing various
foods in the lab's custom paper food packaging made of Pyrus pyrifolia coated with the
anthocyanin extract. While the paper's color remained relatively slightly changed after
being left with fresh products, it underwent noticeable changes after being used with
perishable foods like rice and cooked meat as time went on. In addition, a pH test was
performed to measure the degree of reaction between acids and bases on the P. pyrifolia
and anthocyanin paper. Paper made from P. pyrifolia and anthocyanin reacts effectively
and reliably with different acids and bases, suggesting its potential for various
52
applications in the paper industry and other fields requiring accurate and sensitive
detection of pH changes; according to the results, anthocyanin is an efficient way on
determining the expiration date of perishable goods without an explicit expiration. FTIR
spectroscopy discusses how the paper is considered high quality by its FTIR spectral
absorption peaks; it can be used to infer the types of chemical bonds and functional
groups present in the paper. In order to determine the quality of the paper, scientists
analyze its FTIR spectrum to determine the different types of chemical bonds and
functional groups present. The hydroxyl and alkane stretches, ester and carboxylic acid
vibrations, and water absorption characteristics are some functional groups detected by
FTIR spectroscopy in paper made from Pyrus pyrifolia wastes and carboxymethyl
cellulose. Hydroxyl stretch vibrations are characteristic of cellulose and carboxymethyl
cellulose. The paper's structure exhibits alkane stretch vibrations, which indicate the
presence of long carbon chains. Carboxymethyl cellulose helps the paper bind with water
and contributes to the ester stretch vibrations. FTIR spectroscopy demonstrated the
effectiveness of the P. pyrifolia and anthocyanin paper in terms of its durability, stiffness,
water absorption, and texture. After conducting the One-way anova the researchers fhad
found to reject the null hypothesis revealing that Pyrus pyrifolia (Asian Pear), Brassica
oleracea L. var. capitata f, rubra (Red Cabbage), and carboxymethyl cellulose can be
used to manufacture food packaging that possess exceptional durability and toughness.
53
CHAPTER 5
SUMMARY OF FINDINGS, CONCLUSION, AND RECOMMENDATION
This chapter presents the summary, conclusion, and recommendations that were
constructed based on the work done throughout the study. The study is on the
effectiveness of Pyrus pyrifolia (Asian Pear) Waste, Brassica oleracea L. var. capitata f,
rubra (Red Cabbage), and Carboxymethyl Cellulose (CMC) in producing durable and
efficient food packaging.
To determine this, the researchers considered the paper quality, reaction of
anthocyanin, and food packaging quality through various experimentation processes.
Summary of Findings
The primary findings are as follows:
1. How much Pyrus pyrifolia waste, Brassica oleracea extracts, and
carboxymethyl cellulose is needed to manufacture a single food
packaging?
Manufacturing a single 8x10 inch piece requires 500 grams of P. pyrifolia,
180g Brassica oleracea, and 120 grams of carboxymethyl cellulose.
2. What concentration of B. oleracea extracts is needed to accurately determine
food spoilage?
Anthocyanin extraction using a 50% water and 50% methanol solution
was found safe and effective.
54
3. What is the difference between the quality of food packaging made of P.
pyrifolia wastes, Brassica oleracea extracts, and carboxymethyl cellulose
and conventional food packaging in terms of the following:
A. FTIR Analysis Result
The presence of long carbon chains is evidenced by the presence of
alkane stretch vibrations in the paper's structure. The ester stretch
vibrations in the paper are enhanced by carboxymethyl cellulose, which
also aids in the paper's binding with water. The superiority of the P.
pyrifolia and anthocyanin paper in terms of durability, stiffness, water
absorption, and texture was confirmed by FTIR spectroscopy.
B. Stripping Quality/Weight Capacity
After conducting the stripping quality test, it was discovered that
the P. pyrifolia, CMC, and Brassica oleracea food packaging was much
more durable than the standard food packaging as it can carry more than 5
kilograms of food.
C. Effectiveness of Anthocyanin in Color Alteration
Positive results were achieved through all food types tested on the
food packaging. The color changes were very evident, indicating food
spoilage as time passed.
The overall computed F-value of 8.54 was more significant than the critical value,
5.3177 at a 0.05 level of significance. Therefore, through sufficient evidence, the
researchers rejected the null hypothesis. Thus, Pyrus pyrifolia (Asian Pear), Brassica
55
oleracea L. var. capitata f, rubra (Red Cabbage), and carboxymethyl cellulose can be
used to manufacture food packaging that possesses exceptional durability and toughness.
From these data, the following findings are generated:
1. Food packaging made of P. pyrifolia is somewhat brittle in texture but is
very sturdy.
2. Carboxymethyl cellulose contributed to making it very durable and can
withstand the weight of food.
3. The anthocyanin from Brassica oleracea L. var. capitata f, rubra (Red
Cabbage) was very effective in determining the pH levels of substances.
Conclusion
Based on the summary of the findings and studies the researchers have concluded that:
1. An optimal composition of 500g Pyrus pyrifolia, 180g Brassica oleracera, and
120g CMC creates durable 8x10-inch food packaging.
2. The packaging exhibits stripping quality, withstanding weights up to 5kg,
surpassing regular paper.
3. A 50% water and 50% methanol solution safely extracts anthocyanins, ensuring
efficiency and reduced risks compared to pure methanol.
4. FTIR analysis confirms functional groups in cellulose-based paper, supporting its
durability, stiffness, water absorption, and potential for sustainable paper
production.
56
Recommendations
This section contains the researchers' recommendations. This recommendation
was based on the data gathered throughout the study.
1. The researchers suggest testing the paper packaging with other methods such as
the COBB measurement, burst strength, and the tearing quality if provided with
sufficient equipment. Given the sufficient time, the researchers also recommend
testing for the deteriorated period and shelf life of the packaging.
2. It is advised to attempt the study using substitute anthocyanin sources when
conducting the study to test whether a more economic food packaging would be
possible.
3. Due to lack of resources, the researchers were unable to test the packaging on a
wider variety of food. Therefore, conducting tests with a wider variety of food
items would provide a more comprehensive evaluation of the packaging's
accuracy in detecting color changes
4. The researchers recommend attempting other types of packaging like paper bags
or food cartons for more versatility.
57
Appendices
Table 3. FTIR Spectroscopy results
Frequencies (cm-1)
Structure/
Cellulose,
Paper made of
(Standard)*
Pyrus pyrifolia
Bonds*
Compound
Type*
wastes and
carboxymethyl
cellulose
3340
3338.71
Hydroxyl
O–H Stretch
2918
2917.77
Alkane
C–H Stretch
Ester
C=O Stretch
2849.96
1735
1736.51***
Carboxylic Acid
In the same range:
C=O Stretch
1640
1636.21
Adsorbed Water
1511.30**
Aromatic
58
Aryl C=C Stretch or
Aryl C–C Stretch
1503.72**
1463.07
O–H Bend
Alkane
C–H Bend
1425
1432.05***
Carboxylate anion
Alkane
(COO)– Stretch
1375
1377.28
1317
1315.61
1248
1244.75
Ester
C–O Stretch
1158
1159.17
Alcohol
C–OH Bend
1100
1103.77
Ether
1030
1031.64
899
872.99**
Aromatic/Alkane
718.75
Alkane
C–H Bend
C–O–C Stretch
C–H Bend
–CH2 Skeletal
Vibration
668
664.16
59
Hydroxyl
O–H Bend
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