Ultra heat treatment (UHT) is a type of milk treatment in which all bacteria are destroyed at high temperatures to extend their shelf life up to 6 months as long as the package is not opened. The milk is first homogenized, then heated to 138 degrees Celsius for 1 to 3 seconds. The milk is immediately cooled and packed in a sterile container. As a result of this treatment, all pathogenic bacteria in the milk are destroyed, unlike if the milk is only pasteurized. Milk now lasts 6 months when not opened. UHT milk should only be refrigerated after the packaging has been opened, making it easier to ship and store. But in this process there is a loss of vitamin B1 and vitamin C and there is also a slight change in the taste of milk. [95] Pigs are almost never milked, although their milk is similar to cow`s milk and is ideal for human consumption. The main reasons for this are that milking the many small nipples of a sow is very heavy, and sows can not store their milk like cows. [61] Some hog farms sell pork cheese as a novelty; these cheeses are extraordinarily expensive. [62] A dose of milk is an “effeminate and foolish man,” a phrase attested in the late 14th century.
[14] Milk toast is a dish consisting of milk and toast. His sweet blandness served as inspiration for the name of the shy and ineffective comic book character Caspar Milquetoast, drawn by H. T. Webster from 1924 to 1952. [143] Thus, the term “milquetoast” entered the language as a label for a shy, narrowed, apologetic person. Milk toast also appeared in Disney`s Follow Me Boys as an unwanted breakfast for aging main character Lem Siddons. In Finland, where about 17% of the Finnish-speaking population suffers from hypolactasia[114], “HYLA” (an acronym for hydrolyzed lactose) products have been available for many years. Lactose from low-lactose cow dairy products, from cheese ice cream, is enzymatically hydrolyzed to glucose and galactose.
The ultra-pasteurization process, combined with aseptic packaging, ensures a long shelf life. In 2001, Valio launched a lactose-free milk drink that is not sweetened like HYLA milk, but tastes fresh like regular milk. Valio has patented the chromatographic separation process for lactose removal. Valio also markets these products in Sweden, Estonia, Belgium[115] and the United States, where the company claims that ultrafiltration is used. [116] Glass milk bottles are rare today. Most people buy milk in bags, plastic bottles or plastic-coated paper boxes. Ultraviolet (UV) light from fluorescent lamps can change the taste of milk, so many companies that once distributed milk in transparent or highly translucent containers now use thicker materials that block UV light. Milk is available in a variety of containers with local variants: the incorporation of fat into recombinant products has always been a relatively difficult process. The grease must be properly dispersed and emulsified, which places certain demands on the processing equipment and process parameters. Traditionally, the melted fat is dosed in the line in continuous operation, followed by a thorough mixing in a static or mechanical mixer before entering a homogenizer. In modern systems equipped with high-shear mixers, grease can be dosed directly into the mixing container of the unit. The dispersion of the fat is sufficient to produce a stable emulsion, which makes it possible to eliminate homogenization at this stage of the process.
Later, the recombinant products are finally homogenized during pasteurization or UHT treatment. In small series production, fat is sometimes added to milk in a mixing tank. To ensure that the composition of the product is uniform when pumped for further processing, the milk should be carefully stirred, often with a high-shear agitator. Even if a homogenizer is integrated into the system, it is important that the fat is evenly distributed in the food. Sometimes an emulsifier is added to facilitate and improve the emulsification of milk fat. Recombinant cream can be made from skimmed milk powder or buttermilk powder and anhydrous milk fat up to a fat content of about 40%. Stability is improved by the addition of emulsifiers and stabilizers. Milk stored by the UHT process does not need to be refrigerated before opening and has a much longer shelf life (six months) than milk in regular packaging. It is usually sold uncooled in the UK, US, Europe, Latin America and Australia. To “milk” someone, in the colloquial language of many English-speaking countries, is to take advantage of the person, by analogy with the way a farmer “milks” a cow and takes its milk. The word “milk” has had many slang meanings over time. In the 19th century, milk was used to describe a cheap and highly toxic alcoholic beverage made from methylated spirits (methanol) mixed with water.
The word has also been used to mean cheating, being inactive, intercepting telegrams addressed to someone else, and weakening, or “milksop.” In the mid-1930s, the word was used in Australia to refer to the suction of gasoline from a car. [144] Worldwide, more than six billion people consume milk and dairy products, and between 750 and 900 million people live in dairy households. [12] Vegetable milk is increasingly consumed as a vegetable alternative to milk. [13] Minerals or milk salts are traditional names for a variety of cations and anions in beef milk. Calcium, phosphate, magnesium, sodium, potassium, citrate and chloride are all included and usually occur at concentrations of 5 to 40 mM. Milk salts interact strongly with casein, especially calcium phosphate. It is present in excess and often much greater excess solubility of solid calcium phosphate. [77] In addition to calcium, milk is a good source of many other vitamins. Vitamins A, B6, B12, C, D, K, E, thiamine, niacin, biotin, riboflavin, folate and pantothenic acid are all contained in milk.
Figure 18.5 shows a large recombination system for continuous operation in which grease is dosed in the mixer container. .