EXAM 2: Dairy Products Flashcards
What are examples of dairy products
Milk
Cream
Half-n-Half
Buttermilk (sour milk)
Cheese
Cottage cheese
Cream cheese
Yogurt
Sour cream
What are some examples of dairy alternatives
Plant-based alternatives to milk
- soy, almond, rice, coconut, oat, hemp, flax
Other milk alternatives
- lactose-free
- milk, yogurt, ice-cream, cheese
- tofu
What are four functions of milk in foods
Beverage base
Food Products
Ingredients in recipes
Food industry
What are examples of milk as a beverage base
Smoothies, milk shakes, kefir, egg nog, buttermilk
What are examples of how milk acts in food product
Cheeses: fresh, aged, etc. ; Sour cream; whipped cream
What are examples of how milk is used as an ingredient used in recipes
Pizza, cheese soufflés, casseroles, sandwiches, soups, dressings, infant formula, cookies, puddings, etc.
What are examples of the food industry use of milk
Add nutritive value, provide moisture, improve mixing ability, foaming, texture, flavor
Breed of the cow determines….
Milk characteristics
What are the milk characteristics from holstein cows
Most common breed
High efficiency milk production
What are the characteristics of milk from a Jersey cow
Smallest breed
Produces milk with higher butter-fat content
What are the guidelines and oversight for milk production and sale to humans
Milk is carefully tested and regulated to ensure quality and safety to consumers
How are growth hormones overseen to ensure safety and quality milk production
Milk naturally contains a few parts per billion of bovine somatoropin (bST); it is non-reactive in humans
If rbST is given to cows, the amount in milk is similar to the amount of bST naturally found in milk
How are antibiotics and pesticides overseen in milk production to ensure safety
It is against the law to sell milk with antibiotics or pesticides in it
Milk is rigorously and regularly tested and tested at different steps between processing and being available to humans for consumption
Milk that fails this testing is destroyed
What is the composition of milk
What is the carbohydrate content of milk
Lactose is the primary sugar
- less soluble than sucrose
- non-fat milk dried milk: increase crystallization
- produce sandy texture in ice cream
- aids in browning of baked goods
What is the protein contents of milk
Contains all EAA
Predominate types of proteins
- casein (80%)
- can be precipitated w/ acid or enzymes
- whey (20%)
- by-product of cheese production
- water (93%)
- lactose
- why proteins: lactalbumin and lactoglobulin
What are the fat contents of milk
Referred to as butterfat
Amount varies by cow breed
Contributes to flavor, mouthfeel, and stability of milk products
Fatty Acid composition:
- increased saturated fatty acid: mostly palmitic with lesser amount of myristic and stearic acids
- increased monounstaturated fatty acids: oleic
- SCFA “butyric”: adds to flavor
What is milk
Milk is an emulsion of fat globules and casein, suspended in water
What are casein micelles
Large complex of proteins
- ph sensitive: forms very large curds in acidic environments
- good sources of: calcium, riboflavin, vitamins B12, potassium, phosphorus, vit A and D (typically fortified)
- poor sources: iron, vit c, vit e, vit k
What is raw milk
Non-homogenized or pasteurized
- may have dangerous pathogens
What is milk processing
Fluid milk sold in stores is processed by: homogenization & pasteurization
What is homogenization
Fat micelles broken into tiny fat droplets
- surface surrounded by lipoprotein membrane and casein molecules
Casein weights down globules
What is pasteurization
Heat treatment at high temperatures to kill pathogens in dairy products
What are the benefits of pasteurization
Destroys 100% of pathogenic bacteria, yeasts, and molds
Decreases foodborne illness
- typhoid
- diphtheria
- scarlet fever
- tuberculosis
Decreases spoilage rate
What are some of the disadvantages of pasteurization
Decreases some vitamins
Destroys nonpathogenic bacteria
Denatures proteins
Lipase (promotes hydrolysis rancidity)
Macroglobulin
Know table 10-5 type of processing and refridge required only!
What are factors o to consider when using milk products in food preparation
Flavor changes
Coagulation & precipitation (forms a curd/skin)
Flavor/Mouthfeel Changes
Curdling
Skin Formation
Preventing skin formation
Factors to consider when using milk products in food preparation: Coagulation & Precipitation
Forms a curd/skin
- heat
- acids
- phenolic compounds
- enzymes
- salts
Factors to consider when using milk products in food preparation: Flavor / Mouthfeel Changes
Bland slightly sweet flavor comes from lactose, salts, sulfur compounds and short chain fatty acids
Fats creates the mouthfeel & body of milk
Taste influenced by: heat, sunlight, oxidation, copper equipment, utensils or feed interested by the source animal
Factors to consider when using milk products in food preparation: Curdling
The process where milk proteins solidify and separate from whey
Causes of curdling:
- strong acids - pH<4.6
- heat
- enzymes
- salts
Sources of acids
- citric (tomatoes, lemon and lime juice)
- tannins (potatoes) - polyphenolic compounds
Reduce curdling
- add acid to milk base in the presence of a starch
- reduce temperature and time
The process where milk proteins solidify and separate from whey
Causes of curdling:
- strong acids - pH<4.6
- heat
- enzymes
- salts
Sources of acids
- citric (tomatoes, lemon and lime juice)
Tannins (potatoes) - polyphenolic compounds
Factors to consider when using milk products in food preparation: Skin formation
Causes: water evaporation that results in concentrated casein, fat, & mineral salts on the top
Preventing skin formation
- decrease temperatures and cooking times
- cover the pot w/ a lid
- stir continually while heating
- coat the surface with a layer of melted fat
What are examples of whipped products
Whipped Cream
Whipped Evaporated milk
What is whipped cream
Higher fat content (>30%)
Use cool cream - 45 deg F
Age - at least one day old
Powdered sugar stabilizes the foam
Time
What is whipped evaporated milk
Milk solids allow it to be whipped
Temp - 32 F
Strong flavor
What are examples of cultured milk products
Yogurt, buttermilk, sour cream
What is yogurt
A fermented milk product with at least 8.5% MSNF and 0.5% acid
What is buttermilk (or sour milk)
Skim or part-skim milk that is treated with bacteria
- lactobacillus Bulgaria and streptococcus lactic
Lactose -> lactic acid (decreases pH)
- proteins precipitate out making thicker milk
What are the uses of buttermilk
Adds moisture and tanginess to baked products
Provides acid for leavened products
What are substitutions for cultured buttermilk
1 cup milk and 1 tbsp lemon juice or vinegar, let sit for 10 mins
Or dried buttermilk powder
What is sour cream
Fermented light cream or half-n-half
Acidity: 0.5%
Milk fat: min 18%
Thicker sour cream has vegetable gums, MSNF, or enzymes added
Light/low fat versions
- 1/2 the fat content
- be familiar with the steps and what occurs during the steps of cheese making
Look in the textbook
What are the general steps of cheese making
Milk selection -> Acidification -> Curd Treatment -> Fermentation
What occurs during the acidification step of cheese making
An enzyme is added (ex. Renin) or an Acid is added
Coagulation occurs
What occurs during the curd treatment phase of cheese making
Cheese curd (solid portion) is separated from whey (liquid portion)
What occurs during the fermentation phase of cheese making
The curd is ripened (except fresh cheeses)
How is processed cheese made
Starts with natural cheese -> grind + blend + heat (pasteurize) + emulsifier-> Process Cheese (+ milk and/or whey solids) -> Process cheese food OR Process Cheese (+ moisture + optional additions: milk solids, sweetening agents, starch, vegetable gums) -> Process Cheese Spread
What are some cheese alternatives
Dairy free, lactose free and soy free cheeses are available
Gums and other additives are added to the cheese to give the product the same texture and melting properties of cheese
What are the benefits of cheese alternatives
Lower in kcal, total fat, and saturated fat
Great alternative for individuals who are lactose intolerant, following a vegan lifestyle, allergic to milk proteins or are allergic to soy protein (only soy-free versions)
What are the disadvantages of cheese alternatives
Doesn’t have the same melting properties
Texture tends to be softer for all types of cheeses
Flavor is not the same as regular cheese - but they are getting better
