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Extraction and Properties of Cellulose from Banana Peels
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Riantong Singanusong1*, Worasit Tochampa1, Teeraporn
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Kongbangkerd1 and Chiraporn Sodchit1
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6
1
Department
of
Agro-Industry,
Faculty
7
and
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csodchit@yahoo.com, Fax: 6655962703
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Environment,
Naresuan
of
University,
Agriculture,
Natural
Phitsanulok,
Thailand.
Resources
E-mail:
* Corresponding author
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Abstract
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The research illustrates the extraction of cellulose from banana peel due to
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removal of fat, protein, and pigments from banana peel cellulose (BPC). The
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optimum extraction and bleaching conditions included using 90% ethanol for
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16 h for fat removing followed by sodium hydroxide pH 11.6 for 24 h for
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elimination of protein and soaking in 15% hydrogen peroxide for 3 h for
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bleaching. The obtained BPC was washed and dried at 60C for 10 h. The
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chemical, physical and microbiological properties and cellulose structure as
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well as functional properties of BPC were studied. The BPC contained some
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impurities and had lower L* value (84.66) compared with commercial
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cellulose (CC, 98.61). It also had higher moisture, fat, protein and ash
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contents as well as water activity but lower in fiber and cellulose contents
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than those of CC. The BPC microstructure was glacial and various sizes.
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The bulk, packed and hydrated densities and water retention capacity of
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BPC were 0.646 g/ml, 0.923 g/ml, 2.5 g/ml, and 2.91 g water/g dried basis,
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respectively. Emulsifying activities and oil retention capacity were 40.70 and
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0.08 (g oil/g dried basis). NMR spectra of BPC indicated that it contained
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some impurities.
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Keywords: Banana peels, cellulose, properties of cellulose, extraction of
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cellulose
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Introduction
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Banana is one of the most extensively consumed fruits in the world and represents
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40% of world trade in fruits. Thailand is one of the largest producing countries of
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banana, especially in Phitsanulok province with planting area of 64,000 ha with
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production of 43,750 ton/ha and the OTOP products (One Tumbon (subdistrict)
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One Product)) from banana was 60-70 ton/day. From the OTOP factories, there
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are a lot of banana peels, which can cause an environmental problem such as bad
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smell and source of human disease. One way of reducing the problem is to change
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the banana peels to the more valuable product, cellulose, that can be more
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extensively used in the food industry.
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Cellulose, the major structure component of plants, is a glucose polymer
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bounded in the -1,4 linkage configuration. The -1,4 linkage allows the cellulose
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polymer to crystallize in a linear configuration, with a high degree of
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intermolecular hydrogen bond, which gives it substantial shear and tensile
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strength. Because of its chemical makeup, cellulose can be purified for use as a
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food ingredient. Cellulose is probably the least soluble of all fiber components,
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being insoluble not only in cold or hot water, but also in hot dilute acids and
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alkalis as well. Cellulose is not biodegradable and not provided energy, therefore,
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remaining waste for excretion. It is used to increase the fecal waste in the
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digestive easy and reduce the risk of colon cancer (Prosky and Jonathan, 1992).
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Cellulose can be extracted from various raw materials such as soybean hull, pea
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hull, corn bran, beet pulp-dried and oat hull (William, 1991). The objective of this
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study were to extract cellulose from banana peels and investigated its functional
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properties for application in food products.
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Materials and Methods
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Materials
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Bananas (Musa sapientum Linn. cv. Mali-Ong) were obtained from the
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market in Phitsanulok, Thailand. The various chemicals used for extraction of
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cellulose were ethanol (AR grade, from Merck KGaA Germany), sodium
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hydroxide (AR grade, from Merck KGaA, Germany), hydrogen peroxide (AR
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grade, from Fisher Scientific, UK), phosphoric acid (AR grade, from Ajax
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Finechem Pty Ltd., Australia) and commercial cellulose (CC; cotton linters or
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cellulose powder, medium fibers produced by Sigma-Aldrich Co., USA), it’s
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distributor by Vejchakit Chemiephan Co., Ltd., Thailand.
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Methods
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Preparation of Banana Peel Powder
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Fresh banana peels (Musa sapientum Linn. cv. Mali-Ong) of maturity
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stage 7 (yellow peel and a little brown spots (Silayoi, 2002)), were purchased
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from the market in Phitsanulok province and immediately cut into 0.3 × 2.5 cm. in
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size and dried at 55°C for 10 h or until reaching a moisture content of 7.5% (dry
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basis) using a hot air convection oven (Model KPO-700). After cooling to room
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temperature, it was weighed, ground and passed through a 35 mesh sieve before
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sampling for its chemical composition analysis (AOAC, 2000) and keeping in a
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polyethylene plastic bag and placed in the refrigerator at 4°C until analysis.
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Extraction of Cellulose
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Extraction of Fat
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The extraction of fat from banana peel powder was adapted from William
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(1991). Banana peel powder was soaked in ethanol solution concentrations of 90,
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95, and 99% for 8, 16, and 24 h. Twenty grams of banana peel powder were
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mixed with 200 ml of ethanol 10% (w/v) in a water bath at 50°C with shaking
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speed of 150 rpm (shaker Model: NB101-MH 25, S/N NBI 10N101M112 from
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Scientific Promotion Co., LTD.). Then it was washed 3 times with distilled water
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and filtered with Whatman paper No. 4 and the defatted banana peel powder was
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dried in the hot air oven (Model KPO-700, from Kittipoom equipment LTD.) at
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80+2°C for 7 h and velocity 304.8 mm/h. The sample soaked in distilled water
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was served as a control.
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Extraction of Protein
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The extraction of protein was adapted from William (1991) and Phongnori
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(2004). The defatted banana peel powder was soaked in sodium hydroxide (1:10
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w/v) at 3 pH levels of 11.6, 11.8, and 12.0 for 8, 16, and 24 h and that soaked in
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distilled water was served as a control. The experiment was conducted in a water
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bath at 50°C with shaking speed of 150 rpm. The samples were washed 3 times
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with distilled water, filtered with Whatman paper No. 4 and dried in the hot air
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oven at 80+2°C for 7 h.
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Bleaching of Cellulose
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The method of bleaching of cellulose powder was adapted from John
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(1983), William (1991), Prakhongpan et al.(2002), and Phongnori (2004). The
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defatted and protein removed banana peel powder was soaked in hydrogen
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peroxide solutions of 10, 15, 20, and 30% for 1.5, 3.0, 4.5, 6.0, and 7.5 h. The
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bleached samples were washed 3 times with distilled water, filtered with
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Whatman paper No. 4 and dried in the hot air oven at 60+2°C for 10 h.
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Properties of BPC as Compared to Commercial Cellulose (CC)
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The obtained BPC and CC were chemically analyzed for moisture, fat,
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protein, carbohydrate, ash and fiber contents (AOAC, 2000) and cellulose content
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(Robinson, 1981). The physical properties were analyzed for L*, a*, and b*
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values (Hunter Lab Model DP– 9000), pH (AOAC, 2000), water activity (water
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activity analyzer Model MB – MIK 3000), water retention capacity and
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oil retention capacity (Ang, 1991), and Pb and Sulfite (Atomic absorption
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spectroscopy, Model: GBC Avanta PM, Australia).
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The microbial properties of BPC and CC were analyzed for total viable
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count, yeasts and molds, Staphylococcus aureus, Pseudomonas aeruginosa,
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Escherichia coli, Salmonella and Shigella (Robinson, 1981).
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Microstructural Characteristics of BPC as Compared to CC
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The microstructural characteristics of obtained BPC and CC were studied
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by using the Scanning Electron Microscope (SEM, model JSM- 5410LV, Japan).
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Functional Properties of Cellulose as Compared to CC
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The obtained BPC and CC were analyzed for bulk density, pack density,
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hydrated density, emulsifying activity and viscosity (Prakhongpan et al., 2002),
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setting volume (Luangpituksa, 1992), and water and oil retention capacities
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(Robinson, 1981).
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Bulk Density
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Fifty g of a pre-weighed graduate cylinder was filled with sample and
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shaken slightly. The volume of the sample was recorded, the content of the
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cylinder was weighed and the bulk density was expressed as weight per volume
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(Prakhongpan et al., 2002). The bulk density was calculated using the following
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equation:
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Bulk density =
(g/ml)
weight of the sample (g)
volume of the sample (ml)
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Packed Density
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A calibrated 10-ml graduated syringe was filled with a known weight of
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sample. Pressure was applied manually until additional pressure would not further
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reduce the volume. The packed density was calculated as weight of sample per
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least volume of sample (Prakhongpan et al., 2002). The packed density was
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calculated using the following equation:
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Packed density =
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(g/ml)
weight of sample (g)
least volume of sample (ml)
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Hydrated Density
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A calibrated 10-ml graduate cylinder was filled with a known amount of
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distilled deionized water, and a known weight of sample was added carefully to
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avoid adhesion to cylinder walls. The difference between the volume of the water
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before and after adding sample was recorded as ml of water displaced. Results
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were expressed as grams of sample per ml of water displaced (Prakhongpan et al.,
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2002). The hydrated density was calculated using the following equation:
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Hydrated density =
(g/ml)
grams of sample (g)
ml of water displaced
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Water and Oil Retention Capacity (WRC, ORC)
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WRC and ORC were analyzed by using a glass rod, 2 g of sample was
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mixed with 30 ml of distilled water in a 50-mL centrifuge tube. The slurry was
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allowed to stand for 10 min, and then centrifuged at 2,000 × g for 15 min. After
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centrifugation, the supernatant was drained and the wet sample precipitate was
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weighed. The result was expressed as gram of water per gram of sample. For oil
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retention capacity, the procedure was similar to the one described for water
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retention capacity except palm oil was used instead of water (Robinson, 1981).
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The water and oil retention capacity were calculated using the following equation:
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Water retention capacity =
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(g water/g dried sample)
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Oil retention capacity
gram of water
gram of sample
=
(g oil/g dried sample)
gram of oil
gram of sample
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Emulsifying Activity (EA)
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Seven grams of sample was suspended in 100 ml distilled water and then
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100 ml soybean oil was added. The mixture was emulsified using a homomixer
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(JKA Ultra Turax-T25) with designation of dispersing tool (S25N 25F) at 1,000
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rpm for 1 min. The emulsion obtained was divided evenly into four 50-ml
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centrifuge tubes and centrifuged at 1,300 × g for 5 min (Prakhongpan et al.,
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2002). The emulsifying activity was calculated using the following equation:
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EA = height of emulsified layer (cm) × 100
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height of whole layer (cm)
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The amount of sample was reduced to 1.75 g when there was no excess
water and oil retained before centrifugation.
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Settling Volume
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Settling volume (SV) of dietary fiber and cellulose samples was measured.
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This experiment was performed by mixing 1 g of sample with 70 ml distilled
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water in a 100 ml screw-cap bottle. These bottles were subjected to ultrasonic
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treatment for 30 min in order to allow water to saturate the samples and also to
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remove some of the excess gas in the mixture. The mixtures were then degassed
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by vacuum suction for 30 min and placed in a cold storage room for 24 h to
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facilitate the penetration of water into the interstices of samples. The individual
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mixture in the bottle was quantitatively transferred to a 100 ml volumetric
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cylinder. The content of each cylinder was adjusted to 100 ml by adding distilled
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water. Settling volume is the volume, in ml, formed by the sample residue layer,
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read by naked eyes after 24 h at room temperature (Prakhongpan et al., 2002). .
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Purity of BPC
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The BPC and CC were analyzed for its purity by using the Nuclear
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Magnetic Resonance Spectroscopy (NMR) (AVANCE 300 MHz Digital NMR
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Spectrometer Bruker Biospin ; DPX-300).
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Sample Preparation and Testing Condition
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All samples were characterized at room temperature (20±1°C) with solid
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state CP/MAS
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frequency of 75 MHz. The spectral parameter used were as follows: 4,000
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numbers of scan (NS), relaxation delay of 4 s., spin rate of 5 kHz and spectral size
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C NMR. CP/MAS
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C NMR spectra were recorded at a
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2 K with 4 K time domain size. Solid state CP/MAS 13C NMR was used to study
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the BPC and CC ultra-structure.
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Statistical analysis
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The experimental design for extraction of BPC was Completely
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Randomized Design (CRD). The data were statistically analyzed using ANOVA,
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and differences in means were analyzed using Duncan’s New Multiple Range
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Test (p≤0.05).
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Results and Discussion
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Chemical Composition of Dried Banana Peel Powder
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The chemical composition of dried banana peel powder of maturity stage 7
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banana is shown in Table 1. It can be seen that banana peels contained mainly
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carbohydrates (56.35%), following by fiber (15.30%), ash (12.62%), moisture
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content (7.65%), crude fat (4.34%), and protein (3.74%).
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Extraction of Fat
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The mechanism of fat extraction from banana peels was due to the
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polarity. Fat contains both hydrophilic and hydrophobic polar. The solute is
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dissolved in a solvent that both substance must have the same properties, as a rule
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“like dissolves like” that the polar solute will be dissolved in polar solvent. Since
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the attraction between polar molecules is a force dipole-dipole and it is insoluble
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in non-polar solvents, fat will be dissolved in alcohol (slightly polar)
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(Rattanapanon, 2002; Intranupakorn, 2007)
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The control (soaked in distilled water) had significantly higher crude fat
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content than those of other samples (Table 2). Ethanol was a solvent used to
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extract fat from the samples. As the extraction time increased, the total fat content
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of the sample significantly decreased (p0.05). It can be seen that the extraction
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time affected the crude fat but the concentration of ethanol (90, 95, and 99%) had
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no effect on the crude fat content. The lowest concentration of crude fat was
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selected. Table 2 shows the lowest crude fat at conditions of 90 % ethanol 16 h,
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90 % ethanol 24 h, 95% ethanol 16 h, 95% ethanol 24 h, 99% ethanol 8 h, 99%
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ethanol 16 h, and 9 9 % ethanol 24 h which were not significantly different
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(p0.05). However, considering the economic point of view, the lower chemical
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concentration for extraction and a bit longer extraction time is likely to be
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negligible. Then the condition of using 90% ethanol and 16 h extraction time was
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selected. This condition was different to that reported by Pongnori (2004) in that
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the condition of cellulose extraction from corn cob was using of 95% ethanol for 8
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h extraction time.
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It is shown from Table 2 that all the samples still contained some fats,
hence lowered their purities.
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Extraction of Protein
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It was found that, the protein content of defatted banana peel powder
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significantly decreased (p0.05) with time of extraction (Table 3). With regard to
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the same extraction time, there was no significant difference (p0.05) in protein
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content between the samples. This indicated that both extraction time and pH had
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more effect on removing of protein from the sample mainly after 16 h at pH 11.8,
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24 h at pH 11.6, 24 h at pH 11.8 and 24 h at pH 12, which had the lowest protein
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content. To save the chemical cost therefore, the extraction condition of 24 h at
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pH 11.6 was then selected for further experiment. This condition was different
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from Prakhonpan et al. (2002) who reported the appropriate pH and time of
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cellulose extraction from pineapple core was pH 12 and 24 h. It was also
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concurrent to the extraction of cellulose from soybean by William (1991).
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However, Pongnori (2004) extracted cellulose from corn cob by using 15%
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sodium hydroxide for 30 min whereas John (1983) reported that cellulose from
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peanut shell was extracted by using of sodium hydroxide with pH 11.2-11.8 for
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24 h. This was due to the solubility of protein increased with increasing pH,
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reaching the maximum at pH 12 and decreasing thereafter pH  12 (Praksash,
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1996; Intarasil and Sringam, 2006).
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Bleaching of cellulose
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The defatted and protein removed banana peel powder was bleached by
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hydrogen peroxide solutions at concentration of 10, 15 and 20% for 1.5, 3.0, 4.5,
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6.0, and 7.5 h. The results are shown in Table 4. The mechanism of pigment
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bleaching from banana peels was due to the oxidizing property. Hydrogen
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peroxide (H2O2) is a strong oxidizer and commonly used as a oxidizing agent that
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oxidizes a range of organic compounds by dissociation into perhydroxyl anion
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under alkaline conditions. In an alkaline aqueous solution, H2O2 first to yield
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perhydroxyl anion; the bleach activator reacts with the formed perhydroxyl anion
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to generate peracid, which is a more kinetically potent bleaching specie than H2O2
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and thus can be used for bleaching under mild conditions such as low temperature
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and reduced the time (Abdel-Halim and Al-Deyab, 2013).
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The L* value significantly increased (p≤0.05) with increasing hydrogen
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peroxide concentration and extraction time at condition of 10% hydrogen
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peroxide. Sample bleached with 15% hydrogen peroxide for 3.0, 4.5, 6.0 and 7.5 h
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and 20% hydrogen peroxide for 1.5, 3.0, 44.5, 6.0 and 7.5 h had significantly
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higher (p≤0.05) L* values than those of other samples. The a* (redness) and b*
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(yellowness) values of BPC and CC were not significantly different (p0.05). To
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save of chemical cost and time, using 15% hydrogen peroxide for 3 h for
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bleaching was selected for further experiment. When comparing this finding with
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cellulose from other raw materials, it was found that cellulose from rice straw was
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bleached by using of 50% hydrogen peroxide for 3 h (Chareonsinsab et al., 2005),
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50% hydrogen peroxide for 30 min for soybean residues (Ranhotra and Gelroth,
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1988) and 35% hydrogen peroxide for 3 h for pineapple core (Prakhongpan et al.,
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2002). The concentration of solution and time of bleaching differed entirely
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depending on natural pigments presented in the raw materials and also level of fat
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and protein residual in the sample.
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Chemical, Physical and Microbial Properties of BPC
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BPC had moisture, total fat, protein and ash contents and water activity
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significantly higher (p≤0.05) than those of CC but lower in fiber and cellulose
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contents (p≤0.05). The L*, a* and b* values of BPC and CC were significantly
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different (p≤0.05). The CC had higher L* (lightness) and a* values (redness) than
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that of BPC. On the other hand, the BPC had higher b* (yellowness) value than
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that of CC. BPC and the CC were also analyzed for total viable count, yeasts and
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molds, Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli,
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Salmonella and Shigella and all microorganisms found in BPC and CC were
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conformed to the Food Chemical Codex (Table 5). The difference of chemical,
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physical and microbial properties between BPC and CC might be due to
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differences in raw materials as well as extraction conditions.
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Microstructural Characteristics of BPC
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The microstructural characteristics of obtained BPC compared to CC by
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using the SEM are shown in Figure 1. It was found that the microstructure of BPC
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was glacial and porous with various sizes. It might be due to the impurities of
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BPC which affected the microstructural characteristics when it was likely to be
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more global in shape rather than fibrous. In contrast, the microstructure of CC was
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fibrous with smooth surface and had a fiber length of about 200-300 µm.
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Functional Properties of BPC
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The obtained BPC and CC were analyzed for functional properties of
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standard cellulose powder according to Food Chemical Codex (FCC) (Robinson,
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1981) and the results are shown in Table 6.
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CC had cellulose content of 98.89% which was in the range of FCC
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(Robinson, 1981) while BPC had lower content than both FCC and CC. The pH
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and loss on drying found in the BPC and the CC were conformed to the
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requirement of powdered cellulose according to FCC. The ash content of the BPC
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was higher than that of the CC and Pb and S were undetectable for both samples.
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The total fat and protein contents of the BPC and CC were 2.57, 0.66 and 1.65 and
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0.26%, respectively, and the total dietary fiber of the BPC ( 9 0 .4 3 %) was also
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lower than those of CC and FCC. This indicated that the selected extraction
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process of BPC was still to be improved. The cellulose extracted from banana
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peels contained high caloric content which was consistent to the results of
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chemical analysis, which showed the remaining of protein, fat and carbohydrate
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contents in the BPC. The water activity and all microorganisms of the BPC and
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CC were conformed to the requirement of powdered cellulose.
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The bulk, packed and hydrated densities of BPC and CC are shown in
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Table 7. The values of BPC were higher than those of CC due to the particle size
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of CC which was smaller. These results were similar to those reported by
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Prakhonpan et al. (2002).
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WRC and ORC of BPC and CC were determined and are shown in Table
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7. BPC had higher WRC (2.91 g water/g dried sample) than that of the CC (1.93 g
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water/g dried sample). Normally, fiber has an ability to absorb water due to the
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large number of hydroxyl groups form hydrogen bond with water. Measuring
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water retention capacity in the fiber's structure found that fiber are both water
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soluble and water insoluble and can absorb large quantities water (Spiller, 2001).
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In addition, Cadden (1987) found that reducing the particle size of cellulose from
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rice bran resulted in lowered water adsorption. These results were consistent to
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BPC which had higher WRC than that of CC. The small particle size had lower
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bulk, packed and hydrated density properties than the large particle due to the
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reduced size of the powder particles damaging the fiber network of the porous
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which can retain water in the structure resulting in lower water absorption (Ang,
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1991; Lario et al., 2004; Sansawat, 2008). Ang (1991) also found that the WRC
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was observed to increase with increasing fiber length.
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The characteristics of fiber in imbibing and swelling in water are
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important not only in food application, but also in human gastrointestinal function
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results of the WRC and ORC analyzed indicate the characteristics of fiber. The
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ability of WRC and ORC of cellulose could be different depending on the nature
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of the raw materials (Chen et al., 1988; Ang, 1991). When compared WRC
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property of cellulose from different raw materials, it was found that mango and
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pineapple core cellulose and orange residue dietary fiber had WRC of 11.4, 9.92,
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and 13.36 (g water/g dried sample), respectively. The cellulose with high WRC is
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suitable for products that need to increase in volume and to improve in texture
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such as bakery products (Chen et al., 1988; Ang, 1991). CC had higher ORC
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(3.17 g oil/g dried sample) than that of BPC (0.08 g oil/g dried sample) which was
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different from those reported by Prakhonpan et al. (2002) and Sansawat (2008).
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They found that the large particle size had higher ORC than small one. When
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compared ORC property of cellulose from different raw materials, it was found
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that orange residue dietary fiber and pineapple core cellulose had ORC of 2.01
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and 2.15 g oil/g dried sample, respectively. The cellulose with high ORC is also
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suitable for products that need to improve in texture.
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CC showed higher emulsifying activity (EA) than that of BPC due to its
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greater ORC (3.17 g oil/g dried sample) than that of BPC (0.08 g oil/g dried
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sample). When compared EA of BPC with pineapple core cellulose, BPC had
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lower EA than that of pineapple core cellulose (4.27 %) (Prakhongpan et al.,
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2002). Setting volumes of BPC and CC were 15.00 and 14.00 m/g3, respectively,
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which were similar to cellulose from pineapple core (14.00-16.25 m/g3)
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(Prakhongpan et al., 2002).
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Purity of BPC
Figure 2 represented the CP/MAS
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C NMR spectra of BPC (A) and CC
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(B). The peak of Figure 2(b) is spectra of pure CC from cotton. It was found that
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the peaks at  61.9 ppm and  64.8 ppm were assigned to the
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for amorphous cellulose and  64.8 ppm for crystalline cellulose). The cluster of
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resonances around the peaks at  72.2 ppm and  75.8 ppm were assigned to C-2,
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C-3, and C-5. The peak at  84.4 ppm and  89.0 ppm were attributed to C-4 and
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the absorption peak at  105.0 ppm was assigned to C-1 of glucose in cellulose
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(Hiroyuki et al., 2002). The peak of Figure 2A was spectra of BPC and found that
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the peaks at  61.9 ppm,  64.8 ppm,  72.2 ppm,  75.8 ppm,  84.4 ppm,  89.0
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ppm and  105.0 ppm were similar to the peak of cellulose from cotton (B) but
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the peaks of BPC at  32.577 ppm,  26.281 ppm and  18.724 ppm were
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identified as impurities. The results indicated that there were still some impurities
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which may be fat, carbohydrate and protein (Table 5) which could not be fully
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extracted from BPC.
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C-6 ( 61.9 ppm
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Conclusion
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The optimal extraction and bleaching condition of BPC included using of
391
90% ethanol for 16 h for removing fat, sodium hydroxide pH 11.6 for 24 h for
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extraction of protein and 15% hydrogen peroxide for 3 h for bleaching,
393
consequently. By using these conditions, however, there were some amounts of
394
fat (2.57%), protein (1.65%) and carbohydrate (53.01%) still remained in the
395
BPC. The BPC was light yellow while CC was creamy white. The microstructure
396
study showed that BPC was glacial, various sizes and more porous, while the CC
397
was fibrous and had smooth surface.
398
The bulk, packed and hydrated densities, WRC, ORC, EA, and setting
399
volume of the BPC were 0.646 g/ml, 0.923 g/ml, 2.50 g/ml, 2.91 g water/g dried
400
sample, 0.08 g oil/g dried sample, 40.70%, and 15.0 ml/g3 respectively.
401
402
References
403
Abdel-Halim, E.S. and Al-Deyab, S.S. (2013) One-step bleaching processing for
404
cotton fabrics using activated hydrogen peroxide. Carbohyd Polym., 92,
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1844-1849.
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407
408
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Ang, J.F. (1991). Water retention capacity and viscosity effect of powdered
cellulose. J. Food Sci., 56(2):1682-1684.
AOAC. (2000). Association of Official Analytical Chemists: Official Methods of
Analysis. 16th ed. Washington, DC.
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410
Cadden, A.M. (1987). Comparative effects of particle size reduction on physical
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structure and water binding properties of several plant fibers. J. Food Sci.,
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52(6):1595-1599.
413
Chen, H., Rubenthaler, G.L., Leung, H.K., and Baranowski, J.D. (1988).
414
Chemical, physical and baking properties of apple fiber compared with
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wheat and oat bran. Cereal Chem., 65(3):244-247.
416
Charoensinsab, M., Limrungruengrat, K., Mondecha, P., and Saengnark, A.
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(2005). Effect of particle sizes on functional properties of cellulose powder
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from rice straw. Thaksin. J., 8(1):47-59.
419
Hiroyuki, K., Shunji, Y., Tamio, S., Masashi, F., Tomoki, E., and Mitsuo, T.
420
(2002). CP/MAS 13C NMR Study of cellulose and cellulose derivatives. 1.
421
Complete assignment of the CP/MAS
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cellulose. J. Am. Chem. Soc., 124, 7506-7511.
423
424
13
C NMR spectrum of the native
Intranupakorn, R. (2007). Monitoring and extraction of herbal essential.
Chulalongkorn. Publishing, Bangkok. 215p.
425
Intarasil, K. and Sringam, S. (2006). Condition for raw materials preparation and
426
extraction of protein from brewer’s spent grain. Proceedings of the 44th
427
Kasetsart University Annual Conference : Agro-Industry, Economics and
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Business Administration; January 30 – February 2, 2006; Bangkok
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Thailand, p. 340-347.
430
431
John, M.G. (1983). Alkaline peroxide treatment of nonwoody lignocellulosics.
US. Patent Number 4,649,113.
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Lario, Y., Sendra, E., Garcia-Perez, J., Fuentes, C., Sayas-Barbera, E., Fernandez-
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Lopez, J., and Perez-Alvarez, J.A. (2004). Preparation of high dietary
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fiber powder from lemon juice by-products. Innov. Food. Sci. Emerg.,
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5:113-117.
436
Luangpituksa, P. (1992). Study on dietary fiber and its mechanism in
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counteracting amaranth toxicity, [Ph.D. thesis]. Graduate School of
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Agriculture, Hokkaido University, Hokkaido, Japan, 109p.
439
Phongnori, J. (2004). The extraction of cellulose from corncob and its application
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in food, [Master thesis]. Naresuan University, Phitsanulok, Thailand, 98p.
441
Praksash, J. (1996). Rice bran proteins; properties and food uses. Food Sci. Nutr.,
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36:537-552.
443
Prakhongpan, T., Nitithamyong, A., and Luanpituksa, P. (2002). Extraction and
444
application of dietary fiber and cellulose from pineapple cores. J. Food
445
Sci., 67(4):1308-1313.
446
447
448
449
450
451
452
453
Prosky, L. and Jonathan, W. DeVries. (1992). Controlling dietary fiber in food
products. Van Nostrand Reinhold Co., New York. 161p.
Rattanapanon, N. (2002). Food Chemistry. Odeon Store, Publishing. Bangkok,
Thailand. 487p.
Robinson, W.B. (1981). Food Chemical Codex 3rd ed. Washington DC, National
Academy Press, 735p.
Ranhotra, G. and Gelroth, J. (1988). Soluble and total dietary fiber in white bread.
Cereal Chem., 65(2):155-156.
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454
Sansawat, T. (2008). Production of dietary fiber powder from powder citrus
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waste. [Master thesis]. Chiang Mai University, Chiang Mai, Thailand, 99p.
456
Silayoi, B. (2002). Banana. 3rd ed. Kasetsart University Publication, Bangkok,
457
458
459
460
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Thailand. 357p.
Spiller, A.G. (2001). CRC Handbook of Dietary Fiber in Human Nutrition. 3 rd ed.
New York, CRC Press, 683p.
William J.V. (1991). Process for recovery of cellulose. US. Patent Number
5,057,337.
462
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463
Table 1 Chemical composition of dried banana peel of maturity stage 7 banana
Chemical composition
464
Dry basis (%)
Moisture
7.65±0.05
Crude fat
4.34±0.74
Protein
3.74±0.42
Carbohydrate
56.35±0.37
Ash
12.62±0.09
Fiber
15.30±0.85
Results are mean ± SD of triplicate analysis.
465
466
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467
Table 2 Crude fat content of BPC after ethanol extraction with various
468
conditions
Sample
Crude fat content (%)
4.34±0.74a
Control
8h
16 h
24 h
90%
0.89±0.07b
95%
0.72±0.07bc
99%
0.35±0.19cd
90%
0.48±0.02bcd
95%
0.37±0.04cd
99%
0.23±0.02d
90%
0.28±0.02cd
95%
0.18±0.02d
99%
0.21±0.02d
469
1
470
Duncan’s multiple range test. Means ± SD of triplicate analysis.
Means with different superscripts in the same column are significantly different (p  0.05) by
471
472
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473
Table 3 Protein content of BPC after sodium hydroxide extraction with
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various conditions
Sample
Protein content (%)
3.74±0.42ab
Control
8h
16 h
24 h
475
476
pH 11.6
3.83±0.45a
pH 11.8
4.15±0.12a
pH 12.0
3.57±0.41b
pH 11.6
3.85±1.00a
pH 11.8
3.27±0.04abc
pH 12.0
3.77±0.85ab
pH 11.6
2.75±0.48c
pH 11.8
2.48±0.03c
pH 12.0
2.48±0.02c
1
Means with different superscripts in the same columns are significantly different
(p0.05) by Duncan’s multiple range test. Means ± SD of triplicate analysis.
477
478
479
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480
Table 4 Color value of BPC after bleaching with various hydrogen peroxide
481
conditions
Color values
L*
a*ns
b*ns
1.5 h
80.08±0.12bc
-1.75±1.11
15.17±0.08
3.0 h
83.44±0.12b
-1.85±1.06
15.97±1.30
4.5 h
83.53±010b
-1.89±1.04
15.87±1.15
6.0 h
83.51±0.17b
-1.87±1.07
15.90±1.23
7.5 h
74.21±0.15c
-1.96±1.06
15.94±1.18
1.5 h
83.68±0.10b
-1.95±1.09
15.25±0.03
3.0 h
84.66±0.11a
-1.91±1.13
16.10±1.18
4.5 h
84.37±0.24a
-1.84±1.06
15.87±1.18
6.0 h
84.72±0.15a
-1.90±1.11
15.94±1.16
7.5 h
84.65±0.07a
-1.95±1.10
16.00±1.28
1.5 h
84.21±0.11a
-1.87±1.05
15.34±0.08
3.0 h
84.77±0.10a
-1.91±1.10
16.14±1.05
4.5 h
84.75±0.09a
-1.89±1.06
16.18±0.88
6.0 h
84.73±0.11a
-1.89±1.04
16.54±0.88
7.5 h
84.89±0.10a
-1.96±1.08
16.57±0.74
Condition
10%
15%
20%
482
1
483
Duncan’s multiple range test.
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ns
485
Means ± SD of triplicate analysis.
Means with different superscripts in the same columns are significantly different (p  0.05) by
Not differ significantly (p> 0.05)
486
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487
Table 5. Chemical, physical and microbial properties of BPC compared to
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CC
Properties
BPC
CC
Moisture (%)
5.16±0.13a
2.25±0.02b
Total fat (%)
2.57±0.10a
0.66±0.06b
Protein (%)
1.65±0.01a
0.26±0.06b
Carbohydrate (%)
53.01±0.64a
24.33±2.87b
Ash (%)
4.04±0.14a
0.03±0.01b
Fiber (%)
33.57±0.65b
72.36±2.87a
Water activity
0.45±1.27a
0.11±0.01b
Cellulose (%)
75.90±1.39b
98.89±0.17a
Chemical
Physical
L*
84.66±0.11b
98.61±0.45a
a*
-1.91±1.13b
0.11±1.18 a
b*
16.10±1.18 a
3.89±0.23b
Total viable count (cfu/g)
1.22  102
1.21 102
Yeasts and molds (cfu/g)
 102
 102
Staphylococcus aureus (cfu /g)
Negative
Negative
Pseudomonas aeruginosa (cfu /g)
Negative
Negative
Escherichia coli (MPN/g)
Negative
Negative
Salmonella and Shigella (MPN/g)
Negative
Negative
Microbial
489
1
490
Means ± SD of triplicate analysis.
Means with different superscripts in the same rows are significantly different (p  0.05) by T-test.
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491
Table 6. Chemical and microbial properties of FCC, BPC and CC
Property
FCC*
BPC
CC
Assay (%cellulose)
97-102
75.90±1.39
98.89±0.17
pH
5.0-7.5
6.05±0.05
4.92±0.77
Loss on drying (%)
≤0.3
4.04
0.03
Heavy metals (ppm as Pb)
≤10
Undetected
Undetected
Fat (%)
0
2.57
0.66
Protein (%)
0
1.65
0.26
99.00
90.43
99.00
0
240
32.40
≤10
Undetected
Undetected
Water activity (25°C)
0.1-0.3
0.30
0.30
Total viable count (cfu/g)
≤1×103
1×102
1×102
Yeast and molds (cfu/g)
≤1×102
0.47
0.11
Staphylococcus aureus
Negative
Negative
Negative
Negative
Negative
Negative
Escherichia coli (MPN/25g)
Negative
Negative
Negative
Salmonella and Shigella
Negative
Negative
Negative
Total dietary fiber (% dry
basis)
Caloric content (kcal/100g)
Sulfite (ppm)
(cfu/g)
Pseudomonas aeruginosa
(cfu/g)
(MPN/25g)
492 *FCC: the requirement of powdered cellulose according to Food Chemical Codex (Robinson,1981)
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493
Table 7. Functional properties of BPC compared to CC
Functional property
BPC
CC
Bulk density (g/ml)
0.6460.27 a
0.1920.01b
Pack density (g/ml)
0.9230.07 a
0.2650.07 b
Hydrated density (g/ml)
2.500.48a
1.670.36 b
Emulsifying activity
40.700.11b
56.050.06a
WRC (g water/g dried sample)
2.910.15a
1.930.82b
ORC (g oil/g dried sample)
0.08.010 b
3.170.15a
Setting volume ns (ml/g)3
15.00.18
14.00.16
494
1
495
Means ± SD of triplicate analysis.
496
ns
Means with different superscripts in the same rows are significantly different (p  0.05) by T-test.
Not differ significantly (p> 0.05)
497
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498
A
499
500
Scanning electron micrograph of BPC, size 100 mesh; Bar = 3 microns
501
B
502
503
Scanning electron micrograph of CC, size 100 mesh; Bar = 3 microns
504
505
506
Figure 1. The microstructural characteristics of BPC (A) compared to CC
(B) with a SEM technique
507
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508
509
A
510
511
512
513
514
515
516
517
518
519
B
520
521
522
523
524
525
526
527
528
Figure 2 Cross polarization/magic angle spinning13C NMR spectra of BPC
(A) and CC (B)
30