Milk flavor

St. Laurent et al. (1990) investigated the effects on milk flavor of a-tocopherol supplementation (0, 700 or 3000 IU/day) to a feed consisting of grain mix, hay and pasture in herds with a chronic spontaneous oxidized flavor problem. a-Tocopherol supplementation resulted in improved milk flavor but no relationship was apparent between milk a-tocopherol levels and the extent of flavor improvement. In this study, the flavor problem decreased significantly when the cows subsequently got access to spring pasture. 

Perceived intensity determination Five experienced panelists rated the intensity of the added hexanal with the sample s background of milk flavor. They marked their PI on a Une anchored at either end with a line scale of 0 (weak) to 100 (strong). 

DeLuca, A.P., Teichman, R., Rousseau, J.E., Morgan, M.E., Eaton, H.D., MacLeod, P., Dicks, M.W. and Johnson, R.E. (1957) Relative effectiveness of various antioxidants fed to lactating dairy cows, on incidence of copper-induced oxidized milk flavor and on apparent carotene and tocopherol utilization. J. Dairy Sci. 40, 877-886. 

Shipe, W.F., Analysis and control of milk flavor, in The Analysis and Control of Less Desirable Flavors in Foods and Beverages, G. Charalambous, Ed., Academ. F ress, New York, 1980, p. 201. 

A dessert made by boiling wheat in milk, flavored with... 

D-fortified foods—Milk 1400 lU/qtl and silsil formute. Other foods to which vitamin D is often added include breakfast and infant cereals, breads, margarines, milk flavorings, fruit and chocolate beverages, and cocoa. 

Although milk is the only food for which vitamin D fortification is recommended by the Food and Nutrition Board of the National Research Council and the Council of Foods and Nutrition of the American Medical Association, other foods to which vitamin D is added include breakfast cereals, infant cereals, breads, margarine, milk flavorings, fruit and chocolate beverages, and cocoa. Concern has been expressed about the possibility of overconsumption of vitamin D as a result of widespread fortification of foods with the vitamin. Obviously, when vitamin D-enriched milk is used in the amount of 1 qt daily, no other source of vitamin D is required. 

Dougherty, R.W., W.F. Shipe, G.V. Gudnason, R.A. Ledford, R.D. Peterson R. Scarpel-lino. 1962. Physiological mechanisms involved in transmitting flavors and odors to milk. 1. contribution of eructated gases to milk flavor. J. Dairy Sci. 45 472-476. 

The most difficult property of fat to replace is flavor. Great expenditure of effort has gone into producing a tme butter flavor as flavor boosters in nondairy fat products and in dairy products including milk, cream, butter, and ice cream. Results have led to a successful dupHcation of buttery flavors which closely match the intended target. 

One frozen dessert is made with Simplesse, a protein-based fat mimetic that contains no fat (37). Other dairy product developments include a fat flavor, produced by encapsulating milk fatty acids in maltodextrins (38) fat-free cottage cheeses and 2% fat milk, prepared by steam stripping cream with partial fat addback, with a cholesterol level about 60% lower than the starting material (39). 

Flavors are often used to create the impression of flavor where Httie or none exist, and they impart food products with a recognizable character. Some food products would not exist without the addition of flavorings, eg, soft drinks, water ices, confectionery, milk desserts, etc. Many food products need a specific flavor note to characterize them among other similar products of the same food category, eg, citms soft drinks, mint candies, gingerbread, yogurt, and cottage cheese. 

In the compounding technique, constituents are selected or rejected because of their odor, taste, and physical chemical properties, eg, boiling point, solubihty, and chemical reactivity, as weU as the results of flavor tests in water, symp, milk, or an appropriate medium. A compound considered to be characteristic is then combined with other ingredients into a flavor and tested as a finished flavor in the final product by an appHcations laboratory. 

A flavor is tried at several different levels and in different mediums until the most characteristic one is selected. This is important because the character of a material is known to change quaUty with concentration and environment. For example, anethole, ben2aldehyde, and citral taste different with and without acid. Gamma-decalactone has different characters at different levels of use. -/ fZ-Butyl phenylacetate with acid is strawberry or fmity without acid it is creamy milk chocolate. 2,5-Dimethyl-4-hydroxy-3-(2Fi)-furanone with acid is strawberry without acid it is caramel or meat. 

Other examples are glycine — formaldehyde, alanine — acetaldehyde, valine — isobutyraldehyde, phenylalanine — phenylacetaldehyde, and methionine — methional (106). Products such as dried skim milk, dried eggs, and dehydrated vegetables and fmits are particularly susceptible to deteriorative flavor changes ascribed to this reaction (Table 10). 

Margarine and butter contain fat plus water and water-soluble ingredients, eg, salt and milk soHds that impart flavor and color to the product. Generally these products are distributed at refrigerated temperatures to retain their quaHty. Greaseproof packaging, such as polyethylene-coated paperboard, aluminum foil/paper, parchment paper wraps, and polypropylene tubs, is used for butter and margarine (see Dairy substitutes). 

If food can be heated quickly to a temperature of I3I°C a lethaUty equivalent to 6 min at I2I°C can be accumulated in 36 s. This rapid heating and cooling of hquid foods, such as milk, can be performed in a heat exchanger and is known as high temperature—short time (HTST) processing. HTST processing can yield heat-preserved foods of superior quahty because heat-induced flavor, color, and nutrient losses are minimized. 

Vacuum Treatment. Milk can be exposed to a vacuum to remove low boiling substances, eg, onions, garlic, and some silage, which may impart off-flavors to the milk, particularly the fat portion. A three-stage vacuum unit, known as a vacreator, produces pressures of 17, 51—68, and 88—95 kPa (127, 381—508, and 660—711 mm Hg). A continuous vacuum unit in the HTST system may consist of one or two chambers and be heated by Hve steam, with an equivalent release of water by evaporation, or flash steam to carry off the volatiles. If Hve steam is used, it must be cuUnary steam which is produced by heating potable water with an indirect heat exchanger. Dry saturated steam is desired for food processing operations. 

Irradiation. Although no irradiation systems for pasteurization have been approved by the U.S. Food and Dmg Administration, milk can be pasteurized or sterilized by P tays produced by an electron accelerator or y-rays produced by cobalt-60. Bacteria and enzymes in milk are more resistant to irradiation than higher life forms. For pasteurization, 5000—7500 Gy (500,000—750,000 tad) are requited, and for inactivating enzymes at least 20,000 Gy (2,000,000 rad). Much lower radiation, about 70 Gy (7000 tad), causes an off-flavor. A combination of heat treatment and irradiation may prove to be the most acceptable approach. 

Yogurt is manufactured by procedures similar to buttermilk. Milk with a fat content of 1—5% and soHds-not-fat (SNF) content of 11—14% is heated to ca 82°C and held for 30 minutes. After homogenization the milk is cooled to 43—46°C and inoculated with 2% culture. The product is incubated at 43°C for three hours in a vat or in the final container. The yogurt is cooled and held at <4.4° C. The cooled product should have a titratable acidity of not less than 0.9% and a pH of 4.3—4.4. The titratable acidity is expressed in terms of percentage of lactic acid [598-82-3] which is deterrnined by the amount of 0.1 AiNaOH/100 mL required to neutralize the substance. Thus 10 mL of 0.1 AiNaOH represents 0.10% acidity. Yogurts with less than 2% fat are popular. Fmit-flavored yogurts are also common in which 30—50 g of fmit are placed in the carton before or with the yogurt. 

Sherbets have a low fat content (1—2%), low milk soHds (2—5%), and a sweet but tart flavor. Ice cream mix and water ice can be mixed to obtain a sherbet. The overmn in making sherbets is about 40—60%. 

It was thought previously that there were no inborn odor preferences that these are learned from experience. However, studies at the MoneU Center have indicated that flavors consumed by a mother and transmitted into the milk influence the feeding behavior of her infant. When mothers consume gadic, their infants feed longer than when no gadic is consumed (7). 

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