Sour milk

Large quantities of evaporated milk are used to manufacture ice cream, bakery products, and confectionery products (see Bakery processes and LEAVENING agents). When used for manufacturing other foods, evaporated milk is not sterilized, but placed in bulk containers, refrigerated, and used fresh. This product is caHed condensed milk. Skimmed milk may be used as a feedstock to produce evaporated skimmed milk. The moisture content of other Hquid milk products can be reduced by evaporation to produce condensed whey, condensed buttermilk, and concentrated sour milk. 

Chemical Designations - Synonyms (9)-Pentaboron nooahydride Chemical Formula BjH,. Observable Characteristics - Physical State (as shipped) Liquid Color Colorless Odor Characteristic strong, pungent foul sour milk. 

Many carboxylic acids were first isolated from natural sources and were given names based on their origin. Fonnic acid (Latin formica, meaning ant ) was obtained by distilling ants. Since ancient times acetic acid (Latin acetum, for vinegar ) has been known to be present in wine that has turned sour. Butyric acid (Latin butyrum, meaning butter ) contributes to the odor of both rancid butter and ginkgo benies, and lactic acid (Latin lac, for milk ) has been isolated from sour milk. 

SM.uerling, m. acidulous mineral water, sparkling mineral water sparkling mineral spring sour wine , cheese from sour milk clover sorrel, wood sorrel. 

Molecules that are not identical to their mirror images are kinds of stereoisomers called enantiomers (Greek encmtio, meaning "opposite"). Enantiomers are related to each other as a right hand is related to a left hand and result whenever a tetrahedral carbon is bonded to four different substituents (one need not be H). For example, lactic acid (2-hydroxypropanoic acid) exists as a pair of enantiomers because there are four different groups (—H, -OH, - CH3, -C02H) bonded to the central carbon atom. The enantiomers are called (-i-)-lactic acid and (-)-lactic acid. Both are found in sour milk, but only the (+) enantiomer occurs in muscle tissue. 

Lactic acid, QH, is the acid present in sour milk. A 0.100-g sample of pure lactic acid requires 12.95 mL of 0.0857 M sodium hydroxide for complete reaction. How many moles of hydroxide ion are required to neutralize one mole of lactic acid ... 

Lactic acid, QH C, is a weak organic acid present in both sour milk and buttermilk. It is also a product of carbohydrate metabolism and is found in the blood after vigorous muscular activity. A buffer is prepared by dissolving lactic acid, HLac (ffa = 1.4 X 10-4), and sodium lactate, NaC3H503, NaLac. Calculate [H+] and the pH of the buffer if it is made of... 

The release of gas causes the batter to rise. The weak acids are provided by the recipe, generally in the form of lactic acid from sour milk or buttermilk, citric acid from lemons, or the acetic acid in vinegar. Baking powder contains a solid weak acid as well as the hydrogen carbonate, and carbon dioxide is released when water is added. 

Common acidic ingredients include vinegar, lemon juice, sour milk, buttermilk, yogurt, tart fruits, and cream of tartar. Commercial bakeries often use ammonium bicarbonate or ammonium carbonate as a leavening agent. The gas-producing reaction with ammonium bicarbonate actually generates both carbon dioxide gas and ammonia gas ... 

Acidulants. The other component of any system of chemical leavening based on sodium hydrogen carbonate is an acid. The original acidulants were sour milk (lactic acid), vinegar (acetic acid), lemon juice (citric acid) and cream of tartar (potassium acid tartrate). All of these will react immediately on mixing so that the carbon dioxide is released straight away. The product had to be baked before the carbon dioxide escaped from the batter or product. The only delay possible was that allowed by the batter viscosity. 

Early routes to AA were complex and expensive. In 1927 the ethylene chlorohydrin process was introduced, but it was also still expensive, and not much commercial interest was stimulated in AA. In 1940 a process came literally right off the farm—pyrolysis of lactic acid, a waste product of the dairy industry found in sour milk. 

Hata Y, Yamamoto M, Ohni M, Nakajima K, Nakamura Y, Takano T. (1996) A placebo-controlled study of the effect of sour milk on blood pressure in hypertensive subjects. Am J Clin Nutr 64 161-11. ... 

Masnda O, Nakamura Y, Takano T. (1996) Anti-hypertensive peptides are present in aorta after oral administration of sour milk containing these peptides to spontaneously hypertensive rats. JNutr 126 3063-3068. 

FORM - Clear liquid with consistency of light vegetable oil. Slight odor and taste of garlic or sour milk (Perception varies with individuals). 

In 1746 Dr. John Roebuck (1718-1794), of Birmingham, and Samuel Garbett substituted lead chambers, each about six feet square, for the glass globes introduced six years previously by Joshua Ward (22), an improvement which cut down the cost of producing the acid to one-fourth of its former amount (12, 13). Three years later, after the substitution of sulfuric acid for sour milk in the old process of bleaching had created a demand for the acid, Roebuck and Garbett erected a sulfuric acid plant at Prestonpans, on the east coast of Scotland (14). Since a salt industry also flourished there, Prestonpans was named for the salt pans. 

Oxalic acid is poisonous to humans, but its concentrations are generally too low in foods to be of concern, although rhubarb leaves are quite poisonous. Lactic acid is produced from the fermentation of lactose, which is the principal sugar found in milk. The taste and smell of sour milk is due to the production of lactic acid from bacterial fermentation. Lactic acid accumulates in our muscles during exercise and strenuous physical activity. It is responsible for the sore, aching feeling often associated with these activities. Benzoic acid is the simplest aromatic carboxylic acid. 

Migration of ethylbenzene Ifom polystyrene into various foods has been reported. The following ethylbenzene levels were found sour milk beverages, < 2.5-6 pg/L noodle soup, 15-21 pg/L noodle curry, 89-153 pg/kg and wantan soup 9-28 pg/L (ECETOC, 1986). Migration of ethylbenzene Ifom polystyrene containers into dairy products resulted in concentrations of ethylbenzene ranging from 2 to 4 pg/kg in yoghurt and 4 pg/kg for chocolate dessert (Ehret-Henry et al, 1994). 

The goods were steeped in water or hot dil. alkaline lyes, after which they were boiled in similar soln., which operation was known as bucking. This done, the goods were exposed to the air on the grass—crofting—and after they had been exposed sufficiently long, they were immersed in sour milk—souring—and the whole operations repeated as often as was necessary. 

Wiley, W. J. 1935. A study of the titratable acidity of milk. I. The influence of the various milk buffers on the titration curves of fresh and sour milk. J. Dairy Res. 6, 71-85. 

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