NTR 307 CH. 10 Milk

Types of Milk

1. 1/2 of milk produced in U.S. is sold as fluid milk and cream 2. much of the rest becomes butter, cheese, and ice cream 3. availability in markets: whole, reduced fat (2%), low fat (1%), and fat-free (nonfat), UHT chocolate, canned, and others 4. dry milk, cream, and cultured milk products (yogurt/buttermilk)

Low-Sodium Milk

1. 1c milk = 120mg of sodium. Low sodium dieters need to watch this 2. these milks contain 6mg per 1c available 3. produced by ion exchange method that removes all but 5% of the original sodium

Fat/Calorie Content of Milks

1. 8 oz. cup = 86-150 calories and 0-8g fat 2. buttermilk contains ~2g fat/cup and fewer than 1/2 calories of whole milk 3. buttermilk was originally the fluid remaining when the fat from whole milk was removed to make butter 4. Condensed milk = ~27g fat 5. Fat-free (non-fat) milk = < 1/2g of fat

Pasteurization

1. A food preservation process in which liquids (milk, beer, soups, or juices, are heated to a specified temperature for a certain period of time to destroy most microorganisms (bacteria, yeasts, molds) that could cause disease, spoilage, or undesired fermentation 2. originally used on wine and beer 3. helped reduce many associated food borne illnesses 4. destroys almost 100% of pathogenic bacteria, yeasts, and molds 5. inactivates many enzymes that cause the off flavors of rancidity 6. almost all milk in N. America that is sold is pasteurized 7. Some states law allow unpasteurized (raw) milk 8. processors measure activity of specific enzymes (alkaline phosphatase) found in milk to ensure sufficient pasteurization has occurred 9. if enzyme is no longer active, milk is safe 10. still spoils b/c 1-5% of nonpathogenic bacteria convert lactose to lactic acid

Homogenization

1. A mechanical process that breaks up the fat globules in milk into much smaller globules that do not clump together and are permanently dispersed in a very fine emulsion 2. prevents separation of water/fat, known as creaming 3. fat is less dense than water, causing it to float to top of milk (results in thick layer of yellowish cream that rises to top of unprocessed milk 4. has no effect on nutrient content; sensory changes occur resulting in a creamier texture, whiter color, and blander flavor 5. coagulates more easily, making puddings, white sauces, and cocoa more viscous 7. increases surface tension, gives a greater foaming capacity 8. more prone to rancidity caused by addition of oxygen to the double bonds of the unsaturated fatty acids 9. Pasteurizing milk before homogenization inhibits rancidity b/c lipase enzymes responsible for breaking down fat are inactivated

Ultrapasteurization

1. A process in which a milk product is heated above 145F (63C) but below 280F (138C) for 0.01 to 15 sec. 2. extends shelf life of milk products, still have to be refrigerated

Imitation Milk

1. A product defined by the FDA as having the appearance, taste, and function of milk (its original counterpart) but as being nutritionally inferior 2. looks like milk but usually has little/no dairy content 3. Ingredients include water, corn syrup solids or sugar to replace the lactose, vegetable oils to replace the milk fat, pretense from the sodium caseinate in soybeans, whey or milk solids-not fat to substitute for the protein, and some stabilizers, emulsifiers, and flavory savings 4. lactose free (useful for people w/ lactase deficiency, but sometimes sodium casein ate and whey are added (makes products inappropriate for people w/ milk protein allergies 5. veggie fat may be high in saturated fatty aids, from coconut or palm oils 6. calcium and protein contents are about 1/2 found in regular milk 7. imitation milk is less nutrient filled and less expensive 8. regulated at state level

Reduced Lactose Milk

1. Any pasteurized milk treated w/ lactase will have most of its lactose converted to its two monosaccharides (glucose + galactose) 2. doubling of sugar molecules results in a slightly sweeter favor: results in milk that is more easily digested by people who have lactose intolerance

Why are fluid milks inappropriate for infants?

1. Cows milk has low iron and vitamin C, lacks critical immunity components for human infants. 2. wait till 1 year of age to introduce cows milk; reduces risk of allergies 3. breast milk and infant formula are the only approved recommendations during infants first year

Whey Powder

1. Crystallizing whey creates a sweet or acidic powder high in lactose + minerals. De-minieralized and de-lactosed whey powders are available 2. Used for infant formulas, baked items, confectionaries, dry mixes, processed cheese, sausages, and weight-loss product formulations

Other Nondairy milks

1. Hemp: newer plant based milk alternative. Non dairy, slightly nutty flavor, "putty" color, made by mixing water w/ crushed seeds of hemp plant 2. Grain: made from oats, barley, wheat, rye, or flour mixed w/ water. Has lower protein content and higher carbohydrate content than dairy milk 3. Coconut milk: can be used as cream substitute, not milk, rich, thick, creamy to add texture to soups/desserts. Lite coconut milk is canned w/ water added, needs to be shaken well to mix cream w/ water. Store in sealed container in fridge for 2-5 days after opening 4. Nut Milk: prepared by grinding nuts such as hazelnuts and mixing them w/ water

Caseins

1. Major proteins found in milk. Extracted from skim milk via acidification or enzyme precipitation 2. improves nutritive value of bakery items, medical foods; binder in processed meats

Vitamins A and D fortification

1. Many milks are fortified w/ these vitamins; both are fat soluble 2. found in milk fat of whole milk (whole milk isn't required to be fortified w/ these vitamins) 3. D: found naturally in very few foods, initially was added to milk to reduce incidence of rickets. Fortification w/ this vitamin in reduced-fat and fat-free milks is optional, 98% of milk processors add it anyway. Required in evaporated whole milk and fat-free milks 4. A: diminished in reduced fat (2%), and fat free (non-fat) milks, dried whole milk, and evaporated skim milk. Fortification of this vitamin is required.

Enzymes

1. Milk also coagulates and forms curds when combined w/ certain enzymes 2. most common is Chymosin (rennin) 3. enzymes coagulated clots are rich in calcium and have a tough, rubbery texture, unlike those created by acid, which are less elastic and more fragile in consistency

Ultrahigh-temperature (UHT) Milk

1. Milk that has been pasteurized using very high temperatures (280F, 138C), is aseptically sealed, and is capable of being stored unrefrigerated for up to 3 months 2. destroys even more bacteria than standard pasteurization and increases milk's shelf life 3. once packaging is broken, it must be refrigerated

Soy Milk

1. Milk-like product that is not from a mammal; made from soybeans that have been soaked, ground, and strained 2. used as a drink, to make tofu (cheese of soy milk), and some infant formulas 3. some vegetarians will use as a substitute for cows milk 4. lacks certain nutrients; only those fortified w/ methionine (essential AA), calcium, vitamin B12, should be substituted for cow's milk for growing children 5. absence of carbohydrate lactose makes soy milk ideal for ppl w/ lactose intolerance

NonFat Dried Milk

1. Removes all moisture from milk results in this 2. can be made from whole, reduced-fat, low-fat, and fat free milks as well as butter milk. 3. nonfat is usually used 4. after drying, A and D may be added, not required 5. originally contained some fat, required to be fortified w/ vitamin A and identified ad "fortified w/ vitamins A and D" 6. reconstituted w/ water and used like fresh milk 7. nutritionally similar to fat-free milk, except vitamin levels can be reduced by 20% 8. absence of fat gives it a long shelf life. can be kept for a year in cool, dry place 9. can be directly added to certain products to boost calcium and protein contents 10. has inferior taste in fluid milks, ideal for making batters and doughs for baked goods

Whey

1. The watery component of milk removed from the curd in cheese manufacture. Insists primarily of water (93%), lactose, and whey proteins (primarily lactalbumin and lactoglobulin) 2. can be isolated by subjecting it to an ultrafiltration process, resulting in protein concentrates that are used extensively by the food industry as emulsifiers and as foaming and gelling agents 3. smaller than casein, more compact, globular, and helical proteins 4. easily separated from the larger caseins by addition of acid (precipitous caseins, but leaves whey in solution) 5. pH lower than 4.6 released calcium phosphate, magnesium, and citrate ions from interior of micelles.

Lactose

1. a disaccharide (galactose + glucose) extracted from the whey found in milk. Makes up 2-8% of milk (by weight) 2. Improves the water-holding capacity of processed meats (ham), texture of frozen desserts such as ice cream, and color of baked goods (browning ability)

Acid

1. adding this causes casein in milk to coagulate 2. casein precipitates when normal pH 6.6 of fresh milk drops below 4.6 3. sources: acidic foods, tomato products, certain fruits 4. some foods must be carefully prepared b/c of coagulating effect of acids on milk products 5. add acid to milk base instead of other way around to prevent milk from coagulating 6. avoid high temperatures after milk has been mixed w/ acid also helps prevent coagulation

Storage: refrigerated

1. all fluid milk (except unopened, aseptic, packages of UHT pasteurized milk and certain canned milks) should be in fridge 2. don't take out unless in use 3. oxidative and hydrolytic rancidity are potential problems in milk and milk products b/c of substantial amounts of short chain fatty acids 4. never drink from container; bacteria in mouth can wash back into product 5. store in proper opaque containers that reduce exposure to light (can trigger oxidation) 6. storage of dairy products can be doubled w/ addition of CO2 (disrupts microbial functions) Milk: no more than 3 weeks yogurt: best consumed w/i first 10 days but can last up to 3-6 weeks Buttermilk: best when used w/i 3-4 days after purchase Sour cream: unopened, up to 1 month, best when used w/i a few days

Ultrahigh-temperature milk (UHT)

1. available in laminated aseptic cartoons, when unopened can be store on shelves w/o fridge for 3 months 2. has a "cooked" flavor at first, tends to disappear as storage of time 3. After 1 year, develops off-flavors described as sweet, flat , musty, rancid, and chalky 4. Chilling b4 serving improves taste 5. once opened, this milk must be refrigerated and handled w/ same care used for fresh milk 6. slightly more expensive than fresh milk and not widely distributed in U.S., but its ideal for boating, camping, hiking, and other situations in which fridge isn't available

Nutrients in Milk

1. basic composition of milk remains same regardless of its source 2. primarily water (87.4%), remaining 13% is carbohydrate, fat, protein, and minerals 3. high water concentration makes pH 6.6 (nearly neutral 4. among domesticated cattle, breed, stage of lactation, type of feed ingested, and season of year tend to slightly influence milk's content

Cultured Milk Products

1. believed to benefit human health 2. examples are buttermilk, yogurt, acidophilus milk, kefir, and sour cream 3. addition of bacterial cultures to ferment their lactose to lactic acid 4. increase acid concentration causes the casein to precipiate out, gives milk a more curd-like consistency 5. type of bacterial cultures largely determines flavor of resulting product 6. some protein is broken down to provide nitrogen for bacterial growth; this makes curd softer and more digestible

Functions of Milk in Foods

1. beverages (smoothies, milk shakes, yogurt drinks, eggnog, etc.) 2. products primarily made from milk are cheese, yogurt, sour cream, and whipped cream 3. many foods rely on milk (pizza, cheese souffles, sandwiches, casseroles, quiches, sauces, etc.) 5. butter is made form milk; all foods w/ this fat are dairy based 6. many proteins in milk are added to many processed foods to improve nutritional value 7. Caseinates contribute to emulsifying and stabilizing 8. whey proteins assist with gelling 9. lactose aids w/ browning and in manufacture of confectionary and frozen desserts 10. milk contributes to processed foods by improving protein content, moisture, mixing ability (emulsification), foaming, texture, and flavor

Flavor Changes

1. bland, slightly sweet flavor of milk comes from lactose, salts, sulfur compounds, and short-chain fatty acids 2. %age of fat determines mouthfeel and body of a particular milk 3. exposure to heat/sunlight, oxidation, use of copper equipment or utensils and feed ingested by animal source are factors that influence milk flavor

Rickets

1. bone softening condition in children 2. common defect is bowed legs

Fat

1. called "milk fat" or "butter fat" 2. plays major role in favor, mouthfeel, and stability of milk products 3. consists of triglycerides surrounded by phospholipid-protein membranes (lipoproteins) which allow them to be dispersed in the fluid portion of milk (primarily water) 4. contains short-chain fatty acids-butyric acid 5. contains medium-chain fatty acids-caproic, caprylic, and capric acids 6. fatty acids in milk fat are ~66% saturated, 30% monounsaturated, and 4% polyunsaturated

Sour Cream

1. can be soured by bacteria or some acidifying agent 2. light cream or half and half is fermented at 72F until acidity from lactic acid reaches 0.5% 3. Thicker sour cream is produced if MSNF, veggie gums, or certain enzymes are added 4. minimum of 18% milk is required, minimum of 14.4% milk fat

Milk protein concentrates (MPC) or milk protein isolate (MPI)

1. casein and whey proteins isolated from fresh nonfat milk (42-85% protein) that are high in bound calcium 2. their natural milk flavor is ideal for infant formula, weight-loss products, sports nutrition items, cheese products, and liquid beverages

Cream

1. collection of fat droplets that floats to the top of non-homogenized whole milk 2. heavier and thicker the cream is, the higher the fat content will be 3. cooling firms its fat globules and makes it even thicker 4. vary in their milk fat content, ranging from a low of 18% to a high of 36% 5. not required to list percentage of fat in the cream on the carton 6. some contain added sugars and stabilizers to improve their taste and texture, some solid in pressurized canisters, provide taste and texture of whipped cream

Whey Protein concentrates (WPC) or whey protein isolates (WPI)

1. concentrated wheys are high in protein (35%, 50-80%, 80 +%protein), but low in lactose and minerals 2. Used for dry beverage mixes, nutrition bars, protein-fortified food, and sports nutrition products

Lactose intolerance

1. condition in which a person is unable to digest lactose b/c of insufficient quantities of lactase enzymes (required to break down lactose disaccharide into its 2 monosaccharide units) 2. common food intolerance 3. fermented milk products containing less lactose are usually more easily digested than those that are not fermented

Buttermilk

1. contains little or no butter fat 2. cultured milk is used in many baked products to add moisture and tanginess and to provide an acid source for leavening 3. low/full fat can be used, with higher - fat products providing more richness 4. traditionally was left over liquid after fresh cream had been chilled and churned to produce butter 5. bacterial cultures convert sugar (lactose) into lactic acid, tastes mores sour than regular milk 6. the more acidic, the more proteins precipitate out (clabbering); thickens milk 7. product is more sour, bubbly, and thicker than regular milk 8. has a long shelf life than regular milk b/c higher acid content that inhibits growth of spoilage causing bacteria and its lower fat content (less likely to go rancid) 9. salt may be added to further inhibit bacterial growth

Rice Milk

1. contains no lactose b/c its made from brown rice, filtered water, and small amount of brown rice sweetener 2. not all are gluten free, some are inappropriate for people w/ gluten sensitivity or celiac 3. some are made by using barley enzymes to convert carbohydrates in brown rice to naturally occurring sugars; some what sweeter than soy 4. flavor can be enhanced by vanilla flavoring

Vitamins

1. contains vitamins A and D, riboflavin (B2), and tryptophan (amino acid important in formation of B vitamin niacin 2. low in vitamins C and E 3. milk exposed to UV light loses riboflavin; package in cardboard/opaque plastic containers to prevent the degradation of this vitamin by light

Color Compounds

1. contributors to this are fat, colloidally dispersed casein and calcium completes, and water-soluble riboflavin (B2) 2. these compounds interfere w/ light transmission, contribute to milk's opaque, ivory color 3. amount of carotene (pigment in some plants) in cow's feed influences color of milk 4. Riboflavin (B2) and carotenoid pigments dissolved in the milk fat contribute to the yellowish tinge of butter and cream

temperature of whipped milk products

1. cooling increases viscosity or fitness and tendency to clump 2. refrigerate at 45F or less for at least 2 hours before whipping

Whipped Cream

1. cream expands 2-3x in volume 2. stability of milk foams is dependent on several factors (fat content, temperature of rem, age of cream, sugar content, equipment used to whip the cream, and length of whipping time) 3. most are sold un-homogenized to allow for easier aggregation of fat globules

Flavored Fluid Milks

1. created by adding a flavoring agent + sugar to milk = more appealing product to customers 2. Flavors include, fruit, chocolate, vanilla, coffee, caramel, cappuccino, peanut butter, root beer, and vegetable 3. Milk = 88% water, so most flavoring agents are water-based so they will dissolve and stay in solution w/i milk

Acidophilus Milk

1. cultured milk created w/ assistance from Lactobacillus acidophilus 2. they break down lactose to glucose and galactose, resulting in twice as many sugar molecules; results in somewhat sweeter milk, usually packaged in cartons, made by inoculating pasteurized milk and letting it incubate until slight curd forms 3. a slightly acidic, sour tastes also results, can be eliminated by mixing bacteria directly to cold milk

Grades

1. done according to bacterial count 2. highest is Grade A (has lowest bacterial count) 3. all Grade A milk/milk products crossing state lines must be pasteurized 4. Grade B is available 5. different grades exist for fat-free (non-fat) dry milk: U.S. Extra and U.S. Standard 6. voluntary, paid for by dairy industry 7. USDA controls this

Nutritionally Altered Fluid milks

1. examples include imitation, filled, low-sodium, and reduced-lactose milks

Kefir

1. fermented milk product and probiotic 2. can be referred to as "champagne of milk" b/c of bubbly fizzy nature 3. made by adding bacteria and yeast to milk. Initially heated to 185F for 1/2 hour and then cooled to 73F which allows milk to ferment to a soft foamy curd 4. strong, tangy, sour taste comes from lactic acid 5. contains 1% alcohol, and a little CO2 as result of fermentation

Yogurt

1. fermented product created when bacteria are added to milk to ferment the milk's lactose to lactic acid 2. bacteria influence acidity, texture, and shelf-life of dairy products to which they're added 3. bacteria is added in during manufacturing process 4. Set style: firm yogurt 5. Stirred style: more runny, semiliquid consistency 6. milk product must contain at least 8.25% MSNF and 0.5% acid

Chocolate Milk

1. flavoring comes from cocoa 2. requires stabilizer to prevent cocoa from settling out of milk (common one is kappa II carrageenan) which reacts w/ milk proteins to produce a gel, giving chocolate milk a thicker mouthfeel than regular milk 3. other stabilizers: cellulose, guar gum, and xanthin gum, which can also add foaming characteristics to milk shake productsGuar or locust gum is used when a thickening quality is desired such as milk in shakes 4. its a suspension in which the continuous phase consists of milk fat and cocoa butter, while the dispersed phase includes cocoa particles, fat-free milk solids, and sugar 5. optional to fortify w/ A and D vitamins in whole milk , but required in fat-free

Other ingredients added to yogurt

1. gelatin, nonfat dried milk (creates firmer texture), reducing the perception of acidity or add color 2. adding sweeteners (sugar, honey, fruit, fruit extracts, flavorings, and alternative sweeteners)

Reduced-Fat and Low-Fat Milks

1. have some of their fat removed so that milk-fat levels are decreased to 2 and 1% 2. minimum of 8.25% mSNF is necessary, but if it exceeds 10% than the milk must be labeled "protein fortified" or "fortified w/ protein" 3. addition of milk solid improves consistency, taste, and nutritive content of reduced-and low fat milks 4. vitamin A fortification is required, vitamin D fortification is optional

Fat Content in whipped milk products

1. higher fat content = more stable whipped cream 2. solid fat creates more rigid foam 3. heavy whipping cream beats more easily than lower fat whipping creams 4. becomes lumpy and buttery when over-beaten

Mechanisms of Health Benefits-Probitics

1. known to create a healthy microbial balance in intestines, aid digestion by producing helpful enzymes, prevent attachment of harmful bacteria either directly as a barrier or indirectly through mucin production, and stimulate immune function 2. large portion of immune system is encompassed by intestinal tract, believed that probiotics may stimulate activity of immune cells

Carbohydrate

1. lactose (milk sugar) = primary type found in milk 2. 12 grams per 8 ounce glass 3. lactic acid produces when bacteria metabolizes lactose 4. flavor of cheeses, fermented milk products (yogurt, and sour cream), is partially derived from lactic acid) 5. lactose = less soluble than sucrose (causes it to crystallize into lumps in nonfat dried milk) and produce a sandy texture in ice cream

Canned Sweetened Condensed Milk

1. large quantity of added sugar, makes ideal for preparation of desserts 2. whole milk is evaporated by 50% by weight, 15% sugar (sucrose), is added. 3. contains at least 28% total milk solids, about 8% milk fat 4. high calorie b/c of extra sugar and concentrated nature of nutrients 5. doesn't have to be sterilized (40-45% by weight sugar concentration prevents microbial spoilage) 6. sugar content contributes to maillard reaction 7. sugar combines w/ protein in milk to give a light brown color during heating

Filled Milk

1. made by replacing all or part of the milk fat w/ a vegetable fat 2. cholesterol Levels drop to zero in this milk, but if fat sub is a saturated veggie oil than there is a higher ratio of saturated to polyunsaturated fats 3. regulated at state level

Caseinates

1. made from casein by adding sodium, calcium, potassium, or combinations of these salts (to make it water soluble) 2. Food bars, medical foods, soups, sauces, whipped toppings, and bakery products

Minerals

1. major one in milk = calcium (1 cup = ~300 mg) 2. 2c of milk/day provides substantial portion of 1,000 mg DRI for adults 19-50 yrs. 3. Milk can also provide calcium in yogurt, pudding, ice-cream, custards, hot chocolate, and cheese 4. others found in milk are phosphorus, potassium, magnesium, sodium chloride, and sulfur 5. Low in iron

Instant milk

1. manufactured by exposing nonfat dried milk to steam, then retried 2. double drying helps achieve ability to agglomerate and instantly dissolve in cold water 3. more milk solids can be added by good manufacturers to make it more flavorful and nutritious

Hydroisolates

1. manufactured by the enzymatic hydrolysis of milk proteins 2. improves the proteins stability, solubility, viscosity, emulsification, and whipping ability

Cultures added to milk

1. microbial food cultures - bacteria, fungi, and/or yeast 2. includes starter cultures (used in fermented foods such as yogurts and breads) 3. can be naturally present w/i food or added intentionally 4. bacteria used is often lactic acid producing bacterial cultures or propionic acid producing bacteria 5. function is culturing or action 6. only food in U.S. that has specific strains of bacteria are mandated as yogurt 7. when microbial food cultures are naturally present in a food, they're not considered an ingredient and are not required to be listed on label 8. when cultures are added, term cultured must follow the name of substrate

Whole Milk

1. milk must contain 3.25% milk fat and at least 8.25% milk solids-non-fat (MSNF) to be in this category 2. milk is usually fortified w/ A and D vitamins, but its optional for this type

Almond Milk

1. milky drink made from ground almonds 2. was made initially b/c of short shelf life of regular milk

Cream Substitutes

1. nondairy fat creamers can last over a year at room temperature, often contain saturated fats 2. nondairy whipped toppings are made from water veggie oil, corn syrup solids, sodium caseinate or soy protein, emulsifiers, veggie gyms, coffee whiteners, and artificial flavors

Fresh Fluid Milks from other Animals

1. not all milk comes from cows, but cows provide almost all milk consumed in N. America 2. goats ranked close second in supplying milk in other regions. Low in folate and Vitamins D, C, and B12 3. Other milk sources are, sheep, camels, reindeer, Llama, and water buffalo

Age

1. older cream is = greater viscosity and ability to foam 2. must be at least 1 day old in order to allow it to incorporate the air necessary for optimal increase in volume

Active Culture yogurts

1. once yogurt has reached desired consistency, fermentation and accompanying changes caused by bacteria are discontinued 2. bacterial growth can be inhibited by either chilling or heating the yogurt 3. if chilled, cultures remind alive, when heated, cultures are destroyed 4. yogurt containing viable cultures are only recommended for those w/ lactase deficiency or those taking antibiotics 5. consuming fermented milk products containing live cultures reportedly helps restore normal intestinal bacteria eliminated by antibiotics (has been associated w/ treatment of diarrhea) 6. intestinal bacteria are beneficial cause they help produce some B vitamins and vitamin K

Eggnog

1. packaged, commercially produced is manufactured to replicate a traditional rich holiday beverage made w/ eggs, cream/milk, nutmeg, and often spirits 2. predominately sold in thanksgiving and christmas time 3. defined as pasteurized and homogenized mixture of milk, cream, milk solids, eggs, stabilizers and spice 4. vary widely and are available in low-fat versions

Canned Evaporated Milk

1. produced by evaporating at least 60% of water found in whole milk 2. contains at least 7.5% milk fat, 25.5% milk solids-not-fat by weight, 34% of its protein is from MSNF, and is fortified w/ vitamin D 3. stabilizers are often added to prevent separation of fat during storage. Fat separation can also be prevented by turning can s over every few weeks 4. process: expose milk to 203F for 10-20 min. (stabilizes casein so it won't coagulate during sterilization). Then heat milk to 121-131F at reduced atmospheric pressure (allows milk to boil w/o reading normal B.P.). Then homogenized, canned, and sterilized 5. High temp. of can and metal of can can impart cooked and off-flavors to evaporated milk products 6. newer techniques expose it to ultrahigh temperatures for longer periods of time, placing in sterilized cans, and aseptically sealing cans 7. UHT version is less viscous, less white, and has different flavor 8. fat-free version is produced from fat free milk. Contains < 0.5% fat, at least 20% total solids, and vitamins A and D

Benefits of Probiotics

1. promotion of general digestive health/wellness 2. studied areas are inflammatory bowel conditions, infant diarrhea, antibiotic-associated diarrheas, infant colic, bacterial vaginosis, irritable bowel syndrome, oral health, lactose intolerance, immune support, and gut transit time

Protein

1. protein in milk is a complete protein; contains all essential amino acids in adequate quantities to support growth/maintenance of life 2. 1 cup = ~8 grams protein 3. 2 cup equivalents of milk provide almost 1/2 of the protein recommended for a healthy adult woman and 1/3 for a man 4. 2 predominate types found in milk are casein (80%) and whey (18%) 5. adding these to to other foods generally improves texture, mouthfeel, moisture retention and flavor 6. whey is often added to foods= especially grains/beans that are low in lysine to improve protein profile

Milk Facts

1. provides complete protein, many B vitamins, vitamins A + D, and calcium 2. 80% of calcium ingested by Americans is derived from dairy products 3. lack of dietary calcium causes poor bone development in children and is a risk factor for osteoporosis (porous bones) 4. Low in vitamins C and E, iron, and contains no complex carbohydrates or fiber

Salts

1. salts in cured ham, can cause milk to curdle 2. salt/salted foods should be added to milk base instead of other way around. Higher temperatures must be avoided after these ingredients are combined

Coagulation and Precipitation

1. some milk proteins coagulate or precipitate to from solid clot, or curd, under certain conditions 2. makes it possible to produce yogurts/cheeses 3. application of heat, and addition of acid, enzymes, polyphenolic compounds, and salts

Canned Whole Milk

1. some ultrahigh-temperature milk is canned for export 2. requirements regarding this content are similar to those for whole fluid milk sold in cartons

Sugar

1. sugar increases stability, add gradually at end 2. lessens likelihood of overheating cream 3. use powdered sugar instead of granulated sugar; dissolves more readily in cold cream and cornstarch acts as stabilizer

Fat-Free or Nonfat Milks

1. terms replaced "skim" 2. removes as much fat as technologically possible results in this type of milk 3. should contain no more than 0.5% milk fat and a minimum of 8.25% MSNF 4. Vitamin A fortification is required, Vitamin D fortification is optional 5. nutritious beverage that delivers more nutrients for fewer calories than the same amount (1c) of a soft drink 6. less of this type is consumed in U.S. than reduced fat 7. overall children are drinking less milk b/c they're drinking more of other beverages (soft-drinks/fruit juices)

Agglomerate

1. to gather into a mass or ball. Incase of milk, smaller protein particles regroup into larger, more porous particles

Food Additives

1. vitamin D and A fortification 2. hormone recombinant bovine growth hormone (rBGH) given to ~5-30% of dairy cattle to make them product about 10% more milk (not defined as food additive) 3. unlikely that rBGH poses any health risk to humans, as this is digested in the stomach 4. Steroid Hormone use is not permitted in dairy cattle (is permitted in cattle raised for meat) 5. consumers have option of purchasing rBGH-free or certified organic milk/milk products

Heat

1. whey proteins lactalbumin and lactoglobulin become insoluble, mesh w/ milk's calcium phosphate and precipitate forming film on bottom and sides of pan. This film can scorch easily 2. scorching can be prevented by constant stirring, slow elevation of temperature, or use of double boiler 3. casein won't coagulate w/ heat unless boiled for long periods of time 4. canned evaporated milk (contains higher concentrations of casein) may coagulate during high heats of sterilization; prevented by warming milk prior to sterilization

Functional Foods-Probiotics

1. yogurt is most common for this 2. probiotics are often added to this b/c they act as food for microorganisms 3. improve health by improving intestines microbial balance

Probiotic Foods/Supplements

1. yougurt, dairy based beverages, breakfast drinks, health snacks or bars, luncheon meats, teas, puddings, and candy 2. can be sold as pills

Dry Milk

2 main types are nonfat dried milk and instant milk

Fresh Fluid Cow Milks

4 major types considered by this term... 1. whole 2. reduced-fat 3. low-fat 4. fat-free

Medical Food

A food to be taken under the supervision of a physician and intended for the dietary management of a disease/condition for which distinctive in nutritional requirements are established by scientific evaluation

Milk solids-non-fat (MSNF)

Federal Standard identifying the total solids, primarily proteins and lactose, found in milk, minus the fat

Whip Time

Over-beating: turns into butter and whey. Cream turns from glossy to curdled looking

Blue-ish Hue in Non-fat Milk

Removing any of fat eliminates proportional amount of carotenoid pigments and solids; results in color change from yellowish-white to bluish hue seen in fat-free (nonfat milk)

Plant Based "Milks"

Soy, Rice, Almond

How is milk dried?

Spray: concentrated milk is sprayed into hot air Foam-spray: sends a jet of hot air into concentrated milk roller: moving pasteurized fluid or condensed milk though two steam-heated rollers

Casein

The primary protein (80%) found in milk; it can be precipitated (solidified out of solution) w/ acid or certain enzymes 2. often referred to as phosphoprotiens b/c they contain phosphorus (and calcium) when at a pH above 4.6 3. When below pH = 4.6, this protein is free of salts 4. not very soluble in water 5. dispersed in milk as suspension of particles "casein micelles"

Coagulate

To clot or become semi solid. In milk, denatured proteins often separate from the liquid by coagulation

Safe Microorganisms for Foods

USDA publishes partial list of microorganisms and microbial derived ingredients

Canned Fluid Milks

Whole, Evaporated, Sweetened Condensed Milks

Chymosin (rennin)

an enzyme sold commercially as rennet that causes milk to clot, forming a curd

Food Allergy

an immune response to a molecule (usually a protein) found in food

Food Intolerance

an inability to digest/absorb certain foods

Whipped reconstituted nonfat dry milk

can be whipped into a foam very unstable, much less expensive and lower in both calories and fat than whipped cream dissolve equal parts of NFDM and cold water, chilling, and then beating until mixture stands in soft peaks

Whipped Evaporated Milk

can whip it 3x its volume flavor, texture, and stability are less acceptable than they are in whipped cream

Probiotics

live microbial food ingredients (bacteria) that have a beneficial effect on human health

Prebiotics

non digestible food ingredients (generally fibers and inulin) that support the growth of probiotics

Whipped milk products

protein in milk products is mechanically stretched into thin layers that trap air bubbles, fat particles, and liquid

Milk Allergy

reaction of a persons immune system to the protein (casein or whey) in milk

Polyphenolic compounds

some fruits, veggies, teas, and coffees contain slightly acidic polyphenolic compounds 2. when combined w/ milk, result in precipitation of proteins 3. allows contribution to curdling of cream/milk

Storage: Dry

store slightly below room temperature do not expose to moisture b/c humidity will cause lumpiness and become stale keep containers tightly closed, minimize oxygen contact (NFDM will keep for a year this way) unopened cans of evaporated and sweetened condensed milks will keep up to a year in dry, ventilated ares, but double that if refrigerated once any milks are opened they must be treated like fresh milks and refrigerated

Curd

the coagulated or thickened part of milk

Cholesterol

~33 mg in a cup of whole milk 18 mg in reduced fat (2%) 4 mg in fat free (non-fat) milk