A Scientific Approach to
Making Cheese
Robert Ickler
Agricultural Instructor
Bangor School District
Adam Wehling
Agricultural Instructor
Mondovi School District
July 20, 2007
Activity Description:
During this lesson, students will be making cheese. The goal is to use inquiry based
learning so students will achieve a deeper understanding of the process and biological
changes during the cheese making process. This activity will take three days to complete.
Day 1 will include providing background information and setting up the procedure and
hypothesis. Day 2 will include students completing the experimentation of the cheese
making process. Day 3 will include follow up questions, completing the lab write up and
an assessment.
Class into which project will fit:
This lesson would fit into the following Agriculture courses:
-Exploratory or Introduction to Agriculture course-Food Science Unit
-Animal Science-Dairy Products & Processing Unit
-Food Science/Biotechnology Course
Part of Class into which project fits:
This lesson will be integrated into a Food Science, Dairy Products and Processing, or
Biotechnology unit. Many agricultural instructors teach and demonstrate the cheese
making process but don’t discuss many of the biological changes that are occurring
throughout this procedure. Another problem is the lack of involvement since 1 vat of
cheese is usually being made. This lesson strives to have all students actively involved
by changing and experimenting with the variables and then analyzing the results with
their own small vat of cheese.
Length of Activity:
The goal of this activity is to last three days for 45 minute periods. Day 1 will include
providing background information and setting up the procedure and hypothesis. Day 2
will include students completing the experimentation of the cheese making process. Day
3 will include follow up questions, completing the lab write up and an assessment.
Outline of Activity:
Competencies/Outcomes/Concepts Presented
-Learn and understand the art of making cheese
-Students will use the scientific process
-Students will use inquiry based learning
-Analyze the impact of changing variables
-Students will work with unit conversions
-Students will document lab observations
-Students will take ownership in this lab experiment
Day 1
Objective 1:
Students will gain background information on the art and process of making cheese.
Objective 2:
Students will select a variable to change and set up their experiment.
Day 2
Objective 3:
Students will complete their experiment by testing their variable they selected in the
cheese making process.
Day 3:
Objective 4:
Students will analyze and interpret their experiment results from the cheese making
process.
Background/Exercises to be included:
History of Cheese making in Wisconsin:
http://www.wisdairy.com/AllAboutCheese/Cheesemaking/HistoryOfCheesemaking.aspx
This website is produced by the Wisconsin Milk Marketing Board and will provide
information on the history of making cheese in Wisconsin.
Wisconsin Cheeses have an illustrious heritage of more than
160 years of quality and craftsmanship. During this long and
rich history, the art and science of cheesemaking have been
captured in time-honored traditions that produce cheese
varieties of unsurpassed excellence. Today, Wisconsin
produces more than 600 varieties, types and styles of
American, international-style and original cheeses that win
more awards than any other state or country.
The story of Wisconsin's dairy industry has roots in prehistoric times. Nature set the
stage for America's Dairyland during the last Ice Age, when glaciers cut through what is
now Wisconsin. As they receded, the massive mountains of ice left behind a countryside
of rolling hills and lush pastureland.
Millions of years later, when European immigrants migrated west, they found the
nation's heartland, which reminded many of their homelands. Climatic conditions suited
farming well, and initially, farmers grew wheat, hops, and other grains. Dairy farming
followed naturally, and dairy farmers soon produced an abundance of top-quality milk.
To preserve excess milk, farmers made cheese. The move from producing cheese for
family use to making cheese to sell was a short step. However, commercial production
of cheese in Wisconsin began on a small scale.
In 1841, Mrs. Anne Pickett made cheesemaking history when she established
Wisconsin's first cottage industry cheese factory using milk from neighbors' cows.
Seventeen years later, John J. Smith obtained the first cheese vat and made cheese at
home in Sheboygan County. Smith also instituted the marketing of cheese outside
Wisconsin.
A year later Hiram Smith, a farmer on the University of Wisconsin Board of Regents,
founded a full-scale cheese factory. He purchased milk from other dairy farmers or
processed their milk for a percentage of the finished cheese. The cheesemaking
industry in Wisconsin had taken hold.
In 1864, Chester Hazen built a factory in Ladoga. Many doubted the success of this
venture, dubbing it "Hazen's Folly." Critics were silenced when, after just one year of
operation, the factory used milk from more than 300 cows to produce Hazen's cheese.
His success heralded the rapid growth of the cheese industry in the state.
Such rapid growth did cause some problems, however. Until
that time, there had been no uniform grading system tied to
standards of identity for cheeses. To remedy the situation, in
1872 the Dairymen's Association, composed of seven leaders
in the dairy industry, sponsored a new Board of Trade in
Watertown to establish procedures to market Wisconsin
cheese. The Board also secured a 60 percent reduction in
freight rates, which contributed significantly to the efficient
marketing of cheese from Wisconsin to other states. Clearly,
cheesemaking had become an important and prosperous
industry for the state.
By 1886, the University of Wisconsin College of Agriculture offered short courses for
dairy farmers and cheesemakers and sent experts in the field to extend the education
process.
In 1890, Stephen Babcock of the University of Wisconsin developed the milkfat test that
allowed dairymen to determine which cows produced the richest milk, the best for
cheesemaking. This test is still used today.
In 1921, Wisconsin became the first state to grade its cheese for quality. This
leadership role in quality assurance coupled with Wisconsin's central location for
distribution enabled the industry to continue to grow rapidly. By 1922, more than 2,800
cheese factories existed in the state.
Cheesemakers and dairy farmers newly immigrating to the United States often chose
Wisconsin as their destination. This influx of talent and energy kept the cheese industry
vigorous. These men and women represented almost every country in Europe. They
arrived with a strong work ethic, determination, treasured family secrets, and the
tradition of making favorite cheeses from the old country. These cheeses quickly gained
popularity in the United States.
Swiss, among the first Old-World cheeses produced in Wisconsin, originated, as the
name suggests, in Switzerland. Italians brought Pasta Filata cheeses such as the
popular Mozzarella and Provolone, as well as the blue-veined Gorgonzola. The French
gave us creamy, soft-ripened Camembert and Brie, as well as Blue varieties. From
Germany came the secrets of Muenster and Limburger. The English contributed
Cheddar, and the Dutch, Gouda and Edam. These immigrants are responsible for much
of the rich variety of cheeses produced in the state. Additionally, innovative Wisconsin
cheesemakers created original cheeses such as Brick and Colby.
By 1945, more than 1,500 cheese factories in Wisconsin produced about 515 million
pounds of cheese a year.
Today, approximately 15,000 dairy farms, with over 1.2 million cows producing an
average of 18,850 pounds of milk each per year, continue the reputation for quality
milk from Wisconsin. Cheesemakers use approximately 90 percent of this milk to
produce cheese at 115 plants.
Wisconsin has more skilled and licensed
cheesemakers than any other state. These
cheesemakers must complete rigorous studies in
dairy science and cheesemaking before they can
be licensed. They also may serve as an apprentice
under a licensed cheesemaker. Additionally,
Wisconsin is the only state to offer a Master
Cheesemaker program, patterned on the rigorous
standards of similar programs in Europe.
These fine craftsmen produce over 2.4 billion pounds of cheese each year, over 25
percent of all domestic cheese. These quantities continue to grow to meet the nation’s
demand for quality and variety of cheese from Wisconsin, America's Dairyland.
For this lesson, an interest approach is necessary for students to see what a desired
mozzarella cheese is like. For this interest approach, 1 pound of cheese should be
purchased and cut into one inch cubes. Students will need to write the observations down
(see attached worksheet).
Mozzarella is described below from the following website:
http://www.wisdairy.com/AllAboutCheese/cheesecyclopedia/default.aspx
MOZZARELLA
Moht-sah-rel´-la
Heritage:
Originally, Italians ate Mozzarella as a soft fresh cheese.
Later, cheesemakers made it with lower moisture to give
it a longer shelf life. After World War II, GIs returned
home with a taste for a delicious new food they had
discovered in Italy – pizza. Today, thanks in large part to
these soldiers, Mozzarella rates second only to Cheddar in
popularity in the United States. Wisconsin cheesemakers
produce close to 650 million pounds of this Pasta Filata
cheese each year.
Pasta Filata refers to the process in which the curds are dipped in hot water and then
stretched and kneaded into parallel strands. This allows Mozzarella to melt and flow and gives
it its characteristic stretch.
Description:
Delicate, milky flavor. Smooth, plastic texture. Whole milk Mozzarella melts and flows when
heated. Part-skim Mozzarella browns faster. String similar, but formed into strips for snacking.
Appearance:
Creamy white, smooth
Texture:
Smooth, plastic
Flavor:
Mild, delicate, milky
Serving Suggestions:
Layer Mozzarella, Roma tomatoes and pesto between two slices of focaccia; grill and serve.
Shred Mozzarella into Mexican-style dishes such as tacos, nachos and quesadillas.
Blend Mozzarella with Wisconsin Fontina and Wisconsin Parmesan to add dimension to your
next pizza.
Give an Italian flair to a traditional meatloaf. Add shredded Mozzarella, black olives, red wine,
oregano and basil to ground chuck. Bake and serve with a chunky garlic tomato sauce.
Goes Well With:
Tomatoes, cured meats, pesto, black olives, roasted red peppers
Light red wines such as Chianti or Barbera
Styles/Varieties:
Mozzarella: 40-pound block, 20-pound block, 8-pound loaf, 5-pound loaf, Shredded 5-pound
bag String Cheese: 5-pound bulk package, 1-pound package, 8-ounce package, 4-ounce
package, 1-ounce snack pack
Performance Note:
Wisconsin cheesemakers produce Mozzarella in reduced-fat, organic, whole milk, low-moisture
whole milk, part-skim milk, and low-moisture part-skim milk varieties. String cheese is a style
of Mozzarella that is shaped into ropes or sticks that "string" when pulled apart. More than
50,000 pizza restaurants produce what has become America’s favorite food for dining out,
takeout and home delivery. Package pizza kits to sell from your cheese department – include
blends of shredded Wisconsin cheeses, sauces and toppings prepared in small-portion
containers. Mozzarella cuts easily with a hand or platform wire or a Chef’s or double-handled
cheese knife. Cross-merchandise prebaked crust and beverages. Great new pizza ideas can
help you capture some of the popular pizza business for your store. Mozzarella made with
whole milk has a creamy texture and melts and flows to cover pizza. Part-Skim Mozzarella
browns better and faster and shreds and slices easier. Over 90% of the pizzas prepared in
foodservice or retail establishments contain a blend of the two cheeses.
Federal Standards of Identity:
Maximum Moisture / Minimum Milkfat in Solids:
Part Skim: 53-60% / 30-44%
Low Moisture/Part Skim: 46-52% / 30-45%
Low Moisture/Whole Milk: 46-52% / 45%
Whole Milk: 53-60% / 45%
:
Ingredients and Purpose:
Control Ingredients:
1 gallon milk (Recommended Vitamin D/whole milk)-not ultra pasteurized
¼ cup cool water (non chlorinated)
1 and ½ Citric Acid
¼ Tablet Rennet or ¼ tsp. liquid rennet
2 tsp Cheese Salt
Potential Variable Ingredients (Pick Desired):
-Milk (ultra-pasteurized and non ultra-pasteurized): Skim, 1%, 2%, Vit. D(whole milk),
-Buttermilk
-Half and Half or Heavy Whipping Cream
-Salt: Table and Sea
-Coagulant Agent: Liquid or Tablet Rennet from either Vegetable or Animal Extract
-Curdling Agent: Citric Acid, Lemon Juice, Mesophilic Acid, Vinegar, Orange Extract
Equipment and Function:
*Heat Source: Water bath or NESCO cooker-to heat the milk
*Thermometer-to monitor the temperature of the milk
*pH paper-to measure the pH of the ingredients as they transition to cheese
*Stirring Sticks-to stir the milk as it’s being heated
*Microwave Safe Cups-to heat the milk in the water bath and cook the curds in to
microwave. Recommended 14-16 ounce cups
*6 inch by 6 inch pieces of cheese cloth-to cover the cups when draining the whey
*Rubber bands: to secure the cheesecloth around the top of the cup.
*Microwave: to heat the curds so they can be stretched and the whey can be drained
*Measuring cups and spoons: to measure and dilute ingredients
*Knife: to cut the curds
*Ice Water-to cool the curds after they are done being stretched
Modified Procedure: for 10 groups per gallon of milk.
1. Dilution Conversions: Since we are making the process more scientific and creating an
experiment, dilution conversions will need to be made for the ingredients.
-Milk: Divide 1 gallon of milk (128 ounces) into 10 cups (12.8 oz. per cup)
-Curdling Agent: 1 ½ teaspoons will need to be divided into 10 equal portions.
For granular, have students weigh mass of 1 ½ tsp and divide this weight by 10.
Students can then weigh out this measurement for their experiment.
-Rennet: ¼ tablet of rennet will need to be crushed and dissolved into ¼ cup of water.
This volume equals 60 ml and after divided into 10 equal portions, students
should 6 ml.
-Salt: 2 tsp salt equals 10 grams. Students will need 1 gram salt.
2. Label cups with students names and then pour 12.8 ounces of milk into each cup.
Check pH of milk. Stir in diluted amount of curdling agent and heat milk to 88 degree F
on medium heat.
3. Once milk reaches 88 degrees F, check pH. Then stir in diluted amount of rennet
solution for 1 minute. Turn heat to low and let sit for 5 minutes. Check pH.
4. Cut curds into one inch cubes with knife.
5. Cover top of cup with cheese cloth and secure with rubber band. Slightly tip cup and
pour off excess whey. Check pH of the whey.
6. Place cup into microwave for 1 minute. Remove and pour off excess whey. Repeat as
necessary until the curds have shrunk and a majority of the whey is removed.
7. Remove cheese cloth and rubber band and take out curds. Check pH.
8. Add diluted amount of salt, 1 gram. Knead until cheese stretches like taffy. Reheat
as necessary for 30 seconds. Proper stretching is done when internal temperature of the
curd reaches 135 degrees F. Check pH of cheese.
9. When cheese has reached desired consistency and is smooth and shiny, place in ice
water until it’s cooled down.
Please see unmodified recipe for original, unscientific procedure for 1 gallon of milk.
Special Needs Adjustment
*Students who are lactose intolerant of who have milk allergens will need to be notified
or where gloves during this experiment.
*Students with special needs will need to have all volumes checked by a teacher and it’s
recommended to have an aid and be partnered with another student without special needs.
References
New England Cheesemaking Supply Company
292 Main Street, Ashfield MA 01330
www.cheesemaking.com
Wisconsin Milk Marketing Board
www.wisdairy.com
Metric Conversions Website
www.metric-conversions.org
Alignments with Wisconsin State Science Standards
A 12.1, A 12.5, A 12.7, B 12.1, B 12.4, G 12.1, G 12.2, G 12.3, G 12.4
Evaluation/Assessment Method
For this lesson, students will need to complete the following questions as a part of their
lab report
Pre-Experiment Observations/Background Information:
Observe the given piece of Mozzarella cheese for the following items:
ColorTexture (squeeze the cheese and pull it apart)SmellTasteWhy are these characteristics desirable for a Mozzarella cheese?
What are some important historical events that have occurred with the art and process of
making cheese?
Experiment Setup:
What are the key steps to making cheese?
What are potential variables that can be changed in the cheese making process?
What variable will you choose to change in the cheese making process?
Hypothesis the result and impact of changing your variable.
Write a protocol for your experiment integrating the variable you are changing.
What will be your measurements for the following items:
Liquids:
Coagulating Agent:
Curding Agent:
Experiment:
What is the pH of the milk prior to heating?
What changes occur after the curdling agent is added and does this change the
composition of the milk during the heating process?
What is the pH of the milk after it reaches the desired temperature?
What changes occur after the coagulating agent is added? What is the pH?
Prior to cutting the curds, what is the pH?
What observations do you have during the curd cutting process?
What is the pH of the whey? Describe the characteristics of whey?
What changes occur to the curds during the microwave heating process?
What is the pH of the final cheese prior to adding salt?
What is the pH of the cheese after adding salt? Describe their characteristics.
After cooling your cheese, how does it compare to the mozzarella purchased from store?
Post Experiment
How did your variable change the finished product compared to the control in terms of:
ColorTexture (squeeze the cheese and pull it apart)SmellTasteGraph and analyze the pH changes that occurred during the cheese making process.
Interpret these results and discuss why these are important in the cheese making process.
Would you repeat this variable change? Why or why not?
What changes would you make if you were to repeat this experiment?
Were your results in alignment with your hypothesis?
Compare your results with your classmates and write the importance of all the ingredients
based upon the different variable changes.