Linda Wozniewski lwoz@iun.edu
Sharon Ramsey

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This presentation was prepared using draft rules. There may be some changes in the final copy of the rules. The rules which will be in your Coaches Manual and
Student Manuals will be the official rules

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Students must wear:
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Closed shoes
Slacks or skirts that come to the ankles
Lab coat or lab apron
Indirect vent or unvented chemical splash proof goggles. No impact glasses or visorgogs are permitted
Long-Sleeved Shirt (if wearing a lab apron)

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Impounded
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None
Non-Impounded
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Homemade viscometer
Standard curve
A writing instrument

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Non-programmable Calculator
1 sheet of paper on which anything is acceptable

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Everything the student will need
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This may include:
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Glassware
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Reagents
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Balances
Hot plates
Thermometers
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Probes
Magnets
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Stirrers

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Chemistry of Food
How to prepare students
Experiment ideas
Resources

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a. Identify the sources of and understand the role of lipids, carbohydrates and proteins typically found in cookies, and use tests to identify these compounds, including the Benedict’s,
Iodine and Brown Bag tests. b. When given samples of sweeteners, use the Benedict’s test to identify reducing sugars. c. When given samples of cupcake ingredients, use the Biuret test to identify and rank the ingredients by protein content.
d. When given formulations, processes, and finished cupcakes, identify the error in the cupcake formulation and/or process used.
e. Use standard labeling regulations to produce a label from information given.
f. Determine the moisture loss and density of cupcakes. g. Identify leavening agents using chemical tests, and understand the role of the leavening agents in baked cupcakes.

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Research! Understand the science first
Experiments – eight mandatory (including
Viscotester Production and Standard Curve)

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The right ingredients
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Liquids….
Lipids
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Leavening agents
Flours
Sweeteners
Must understand WHY you are using the ingredient…what function does it provide?
Teams are limited to listed ingredients

Liquids
Water, Whole
Milk (Cow or
Goat), Skim
Milk,
Buttermilk,
Almond Milk,
Soy Milk,
Coconut Milk,
Eggs, Egg
Substitute
Lipids Leavening
Vegetable oils,
Shortening,
Butter
Margarines,
Chocolate
Baking soda
Cream of tartar
Flavoring
Salt
Flours Sweeteners
Bread flour
Cake flour
Whole wheat flour
Almond flour
Coconut flour
Corn Flour
Rice Flour
Sugar
Brown sugar
Honey
Sucralose
Aspartame
Vanilla
For State &
Nationals
Fructose
Powdered
Sugar
Each recipe must contain at least one egg or one egg substitute equivalent.

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Carbohydrates
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Cox(H
2
O) y carbon along with hydrogen and oxygen in the same ratio as water
Basic unit – monosaccharide
Multiple units –
 disaccharide (2)
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 trisaccharide (3) oligosaccharide (2-10) polysaccharide (>10)

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Sugars
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Monosaccharides
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Glucose, Fructose
Disaccharides
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Lactose (glucose and galactose) milk
Maltose (glucose and glucose) -
Sucrose (glucose and fructose –table sugar
 Reducing sugars
 Examples: glucose, lactose, fructose
 Non-reducing sugar contains no hemiacetal groups.
 Example: sucrose

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Polysaccharides
Examples:
 starch - glucose polymers, found in plants
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 cellulose –found in plant fibers, insoluble
Pectin-units are sugar acids rather than simple sugars, found in vegetables and fruits
Branched vs. linear
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Starches are a mixture of branched (amylopectin) and linear (amylose) polysaccharides

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Benedicts test for sugars
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Iodine test for starch
Positive
Reaction

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The Benedict's test allows us to detect the presence of reducing sugars (sugars with a free aldehyde or ketone group). All monosaccharides are reducing sugars. Some disaccharides are also reducing sugars. Other disaccharides such as sucrose are non-reducing sugars and will not react with Benedict's solution. Starches are also non-reducing sugars.
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The copper sulfate (CuSO
4
) present in Benedict's solution reacts with electrons from the reducing sugar to form cuprous oxide (Cu2O), a red-brown precipitate.
The final color of the solution depends on how much of this precipitate was formed, and therefore the color gives an indication of how much reducing sugar was present if a quantitative reagent was used.
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With increasing amounts of reducing sugar the result will be: green yellow orange red

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The Iodine test is used to test for the presence of starch.
Iodine solution – Iodine is dissolved in an aqueous solution of potassium iodide reacts with starch producing a deep blueblack color.
Although the exact chemistry of the color change is not known, it is believed that the iodine changes the shape of the starch to change the color

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Present as fats extracted from plants or animals (butter, vegetable oil) or as constituents of food (chocolate)
Contributions to foods: texture and flavor
Contain only Carbon, hydrogen and oxygen
Most common form for lipid in foods is as a triglyceride
What difference in texture would you see substituting vegetable shortening or vegetable oil for butter in the formulation?

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Saturated fats have no double bonds in any of the fatty acid chains in the triglyceride hence it is saturated with hydrogen.
Food
Butter
Dark chocolate
Lauric acid
3%
0%
Myristc acid
Palmitc acid
Coconut oil 47% 18% 9%
Stearic acid
11% 29% 13%
0%
3%
34% 43%
Eggs 0% 0.3% 27% 10% Considered not heart healthy
Soybean oil 0% 0% 11% 4%

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Have one
(monounsaturated) or more (polyunsaturated) carbon chains
This means there are one or more double bonds in the chain

 http://www.wellsphere.com/he althy-cooking-article/butter-vsshortening-in-baking/156136
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Conversion between solid structure to a liquid state is called the melting point
How would changing the melting point of the lipid used change the cookie texture?
Brown Bag Test

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Proteins are made up of amino acids
 essential and nonessential
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Contains Nitrogen
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Protein can be found in the flour, egg and milk as well as other ingredients.

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Biuret Test
The Biuret Reagent is made of sodium hydroxide and copper sulfate. The blue reagent turns violet in the presence of proteins, and the darker the purple color, the more protein is present.
Biuret’s Reagent is unstable, but can be mixed on the spot using NaOH & Benedicts

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Used to produce a gas that
'lightens' dough or batter. used to raise baked goods. water a leavening agent (pie crusts, some crackers) air incorporated into batter (angel and sponge cakes) expand when heated and cause the raising of the dough or batter when gas is trapped in matrix of gluten and starch from flour

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Baking soda
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-NaHCO3
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Needs moisture plus an acid
source such as vinegar, citrus juice, sour cream, yogurt, buttermilk, chocolate, cocoa (not Dutchprocessed), honey, molasses (also brown sugar), fruits or maple syrup to react
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 used to neutralize acids in foods around 4 times as strong as baking powder can cause soapy flavor in high amounts

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Baking powder
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NaHCO3 plus acidifier(s) and drying agent (usually an acid salt and cornstarch)
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 can cause acidity and/or bitter off-flavor two acidifiers used in double acting to produce CO2 in two steps
Reacts when moistened and also reacts when heated double-acting is the only commercial baking powder available today.

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• 2 1/4 cups flour
• 1 1/3 cups sugar
• 3 teaspoons baking powder
• 1/2 teaspoon salt
• 1/2 cup shortening
• 1 cup milk
• 1 teaspoon vanilla
• 2 large eggs

2
3
4
5
6
Batch # Flour
1 2 ¼ cups
2 ¼ cups
2 ¼ cups
2 ¼ cups
2 ¼ cups
2 ¼ cups
Leavening agent
None
3 tsps. baking soda
Sweetener Liquid Egg lipid Salt Vanilla
2 large or substitute none ½ tsp. 1 tsp.
milk or sub.
2 large or substitute
3 Tbsp oil ½ tsp. none milk or sub.
2 large or substitute
3 Tbsp oil ½ tsp. 1 tsp.
milk or sub.
2 large or substitute
3 Tbsp oil ½ tsp. 1 tsp.
milk or sub.
2 large or substitute
3 Tbsp oil ½ tsp. 1 tsp.
milk or sub.
2 large or substitute
3 Tbsp oil ½ tsp. 1 tsp.

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Incorporate ingredients
Hydrate dry ingredients
Experiment set 2 explores the best method to mix the batter

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Preheat oven to 350 degrees. Line cupcake pans with paper liners.
Combine flour, sugar, baking powder, and salt in a large mixing bowl. Add shortening, milk, and vanilla. Beat for 1 minute on medium speed. Scrape side of bowl with a spatula.
Add eggs to the mixture. Beat for 1 minute on medium speed. Scrape bowl again. Beat on high speed for 1 minute
30 seconds until well mixed.
Spoon cupcake batter into paper liners until 1/2 to 2/3 full.
Bake for 20 to 25 minutes or until toothpick inserted in center comes out clean.
Cool 5 minutes in pans then remove and place on wire racks to cool completely.

3
2
Batch # Step 1
1 Mix dry ingredients together
Step 4 Step 2
Add liquid ingredients
Step 3
Using spoon, stir ingredients for
30 seconds
Add egg. Use spoon to stir for 1 minute
Mix dry ingredients together
Add liquid ingredients
Pour into blender or use hand mixer and blend or mix 2 minutes
Add egg. Use mixer or blender to blend for 1 minute ingredients together ingredients 1 minute

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Notebook keeping (t eams are encouraged to bake goods, observe and record the differences caused by adjusting the ingredients from the Approved List of
Ingredients)
. Optional but suggested for keeping records of all experimental data and documentation
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May be bound, spiral, or ring
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Must securely hold all items
Don’t erase in lab notebook!
Document all references
Use pen

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i. Experiment Name – 2 Points ii. Hypothesis – 4 points iii. Variables:
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 a. Controlled Variable(s) – 2 points b. Independent Variable(s) – 2 points c. Dependent Variable(s) – 2 points iv. Materials (amount of each ingredient in grams or milliliters)
– 4 points v. Procedure – 10 points vi. Qualitative observations during the experiment (be sure to include sensory score sheet) – 6 points vii. Quantitative observations during the experiment (Data table, graphs-be sure to include nutritional calculations, viscosity testing, density, and crumb testing results) – 10 points viii. Discussion of Results – 6 points ix. References – 2 points

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Use any combination of ingredients from the approved list as well as physical parameter changes
(temperature, cupcake lining materials, etc.) to formulate an ideal team cupcake. Teams may choose variables used in the first two experiments or use new variables. If a recipe from a cookbook or web site is used as a starting source, the source must be listed in the notebook.
Aiming for a density of 0.3 g/ml
Aiming for less than 0.3% of the mass of the cupcake to be left on liner or in crumbs when liner taken off
Must have nutrition food label

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Made from 8 oz Styrofoam cup
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Heat 16 penny nail with tea candle for ~1 minute
(or until it gets too hot to hold)
Punch hole from INSIDE into center bottom of cup
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Place tape over hole
Time how long it takes for same amount of each standard liquid to break flow as it leaves
When determining how much fluid to use, keep a couple of items in mind
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The larger the amount of fluid the less influence reaction time will have on error.
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The amount of fluid the event supervisor is likely to allow the team to have.

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Use same amount of standard fluids to calibrate
Time how long it takes to break stream

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Students need to investigate viscosity of their batters and compare to final results.
The resistance of a fluid to deformation.
Temperature dependent
*Dynamic or simple viscosity
Kinematic viscosity: ratio of viscosity/density
Shear viscosity – reaction to a shearing stress
(pumping, spraying, etc.)
Must know general nomenclature

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Students should measure the density of each of their experimental cupcakes and record
Suggested Density
.28-.329
.25-.279 or .32-.359
.21-.249 or .36-.389
.19-.209 or .319-.42
Less than .19 or greater than .42
Suggested Score
5
4
3
2
1

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Students will create a food label for their cupcakes properly indicating serving size, calories, amount fat, unsaturated fat, saturated fat, carbohydrates, sugars, fiber, and protein, as well as accompanying daily value percentages.
Students are NOT to be scored on how healthy the cupcake is, only on their ability to identify its role in a healthy diet.

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Calorie - amount of heat required to raise the temperature of 1 gram of water 1 degree Celsius.
Kilocalorie (1000 calories) is the unit commonly used to represent energy values of foods -or Calorie with a C instead of a c
Not all carbohydrates (or fats, or proteins) yield the exact same amount of energy when burned in a calorimeter, so common averages from studies (in kcal/g) are used
Carbohydrates average 4.1 kcal/gram in a bomb calorimeter, are about 98% digestible and yield 4 kcal/g when consumed
Proteins average 5.7 kcal/g in a bomb calorimeter, are not as easily digested and yield an average of 4 kcal/g when consumed
Lipids average 9.5 kcal/g in a bomb calorimeter, are 95% digested and yield an average of 9 kcal/g when consumed
Fats (lipids) are the most concentrated source of food calories
Carbohydrates are the cheapest source of calories, proteins the most expensive

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Foods not digested by human digestive system
Two types
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Soluble Fiber-helps regulate blood sugar
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Found in Oats & Oat Bran, some Fruits & vegys
Insoluble Fiber-helps clean out colon
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Found in whole wheat, some fruit skins and vegys

1)
2)
Fill in the following blanks.
a)
There are ___ Calories/gram of fat.
b) c)
There are ___ Calories/gram of carbohydrate
There are ___Calories/gram of protein d)
There are ___Calories/gram of water
Use the nutritional label given for information to answer the following questions: a)
Calculate the Calories in one serving of this product.
b) c)
(1)
Calories from Fat
(2)
Calories from Protein
(3)
Total Calories in one serving
What percent of the carbohydrate Calories come from fiber?
If the daily value of iron is 18 mg per day, calculate the amount (in mg) of iron in one bar of this product.

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The labels will be scored as follows:
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 i. Creative Cupcake name (5 points) ii. Ingredient List in correct order (15 points) iii. Nutritional Facts in correct order (15 points) iv. Package Weight (10 points) v. Company (team) Name and Address in the correct location (5 points) vi. Label Information matches notebook (10 points)

Attribute
Flavor
Aroma
Starch
Dairy/Milky
Sweetness
Vanilla
Texture
Surface
Moisture
Cohesiveness
Stickiness
Circle any of the following if present
Score (Circle for each attribute listed)
1
Terrible
1
Raw or burned
1
Spoiled
1
Way too much or too little
1
Way too much or not enough
2
2
Under or over cooked
2
Moderate off-flavor
2
Moderately too much or too little
2
Moderately too much or too little
3
Average
3
Slightly under or over cooked
3
Slightly off flavor
3
Slightly too sweet or too tart
3
Slightly too much or too little
4
4
Pleasingly cooked
4
OK
4
About right
4
About right
5
Very Pleasing
5
Very Pleasingly cooked
5
Pleasant
5
Perfect sweetness
5
Excellent
1
Really rough
1
Dry
1
Really gummy
1
Really sticky
2
Somewhat rough
2
Moderately dry
2
Somewhat gummy
2
Moderately sticky
3
Moderately rough
3
Somewhat dry
3
Slightly gummy
3
Somewhat sticky
4
Slightly smooth
4
Somewhat moist
4
Falls apart easily
4
Slightly sticky
Gritty
5
Smooth
5
Moisture just right
5
Just right
5
Just right
Oxidized (paint) flavor Sour Bitter Astringent

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For Event Supervisors
 http://mypage.iu.edu/~lwoz/socrime/index.ht
m
For Lesson Plans for classroom use
 http://mypage.iu.edu/~lwoz/socrime/index.ht
m

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We can make viscotesters
We can simulate a standard curve data collection
We can find the viscosity of a batter
We can find the density of muffins
We can work with some tests from a simulated test.
It is your option