Butter lactic

Traditionally, butter was made by allowing cream to separate from the milk by standing the milk in shallow pans. The cream is then churned to produce a water in oil emulsion. Typically butter contains 15% of water. Butter is normally made either sweet cream or lactic, also known as cultured, and with or without added salt. Lactic butter is made by adding a culture, usually a mixture of Streptococcus cremoris, S. diacetylactis and Betacoccus cremoris. The culture produces lactic acid as well as various flavouring compounds, e.g. diacetyl, which is commonly present at around 3 ppm. As well as any flavour effect the lactic acid inhibits any undesirable microbiological activity in the aqueous phase of the butter. Sweet cream butter has no such culture added but 1.5 to 3% of salt is normally added. This inhibits microbiological problems by reducing the water activity of the aqueous phase. It is perfectly possible to make salted lactic butter or unsalted sweet cream butter if required. In the UK most butter is sweet cream while in continental Europe most butter is lactic. 

The cream used for butter may be fresh ( pH 6.6) or ripened (fermented pH 4.6), yielding sweet-cream and ripened cream (lactic) butter, respectively. Sweet-cream butter is most common in English-speaking countries but ripened cream butter is more popular elsewhere. Traditionally, the cream for ripened cream butter was fermented by the natural microflora, which was variable. Product quality and consistency were improved by the introduction in the 1880s of cultures (starters) of selected lactic acid bacteria, which produce lactic acid from lactose and diacetyl (the principal flavour component in ripened cream butter) from citric acid, A flavour concentrate, containing lactic acid and diacetyl, is now frequently used in the manufacture of ripened cream butter, to facilitate production schedules and improve consistency. 

For taste reasons, sweet as well as lactic butter is optionally salted. To this end, brine is added before kneading. For relatively high salt contents (e.g. 2%, in Scandinavian countries), salt is added in the continuous process as a dispersion in a saturated solution. 

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. 

Moiken-butter, /, whey butter, -eiweiss, n. whey protein, -farbstoff, m, whey pigment, -kdse, m. whey cheese, -s aure,/. lactic acid, -wesen, ., -wirtschsft, Moikerei,/, dairy,... 

Hydroxy-2-butanone (acetoin) is a characteristic constituent of butter flavour used for flavouring margarine and can be obtained as a by-product of molasses-based and lactic acid fermentations [49, 71]. The closely related 2,3-butanedione (diacetyl) has a much lower organoleptic threshold than acetoin and is an important strongly butter-like flavour compound in butter and other dairy products [72] in buttermilk, for instance, the diacetyl concentration is only about 2-4 mg [73]. a-Acetolactate (a-AL) is an intermediate of lactic acid bacteria mainly produced from pyruvate by a-acetolactate synthase. In most lactic acid bacteria, a-AL is decarboxylated to the metabolic end product acetoin by a-AL decarboxylase (ALDB) [71] (Scheme 23.5). 

Cultured buttermilk is manufactured by fermenting whole milk, reconstituted nonfat dry milk, partly skimmed milk, or skim milk with lactic acid bacteria. Most commercial cultured buttermilk is made from skim milk. Mixed strains of lactic streptococci are used to produce lactic acid and leuconostocs for development of the characteristic diacetyl flavor and aroma. Buttermilk is similar to skim milk in composition, except that it contains about 0.9% total acid expressed as lactic acid. The percentage of lactose normally found in skim milk is reduced in proportion to the percentage of lactic acid in the buttermilk. According to White (1978), the fat content of buttermilk usually varies from 1 to 1.8%, sometimes in the form of small flakes or granules to simulate churned buttermilk, the by-product of butter churning. Usually 0.1% salt is added. 

Acidity. The development of a fishy flavor in butter is well known. Cream acidities ranging from 0.20 to 0.30% appear to represent those levels at which flavor development is marginal (Parks 1974). Although the development of fishy flavors in unsalted butters is rarely encountered, it is not restricted to those products containing salt. Pont et al. (1960) induced the development of a fishy flavor in commercial butter-fat by the addition of nordihydroguaiaretic acid and citric or lactic acid. In addition, Tarassuk et al. (1959) reported the development of fishy flavors in washed cream adjusted to pH 4.6. 

Fruity flavor in dairy products is the result of ethyl ester formation, usually catalyzed by esterases from psychrotrophic or lactic acid bacteria. Ester formation by P. fragi involves liberation of butyric and ca-proic acids from the one and three positions of milk triglycerides and the subsequent enzymatic esterification of these fatty acids with ethanol (Hosono et al. 1974 Hosono and Elliott 1974). Consequently, among the esters formed, ethyl butyrate and ethyl hexanoate predominate. Pseudomonas-produced fruity flavor can occur in fluid milk, cottage cheese, and butter. 

Most of the methods discussed above have been used with milk but the majority can be applied to other products. Some minor variations in extraction procedures, such as the inclusion of anhydrous sodium sulphate to remove water (Deeth et al., 1983) or inclusion of an aqueous acid wash step to remove lactic acid (Chilliard et al., 1983) may be necessary. Collomb and Spahni (1995) suggested that the above International Dairy Federation reference method could be a universal method if the adaptations made by McNeill et al. (1986) for butter and McNeill and Connolly (1989) for cheese were incorporated. 

Another type of butter is whey butter, and this is produced from cream that has been skimmed off the whey after cheese-making. As the cream in whey butter has been subjected to the controlled lactic fermentation used in the cheese-making, whey butter has a characteristic and stronger flavour than other butters. This does not present any particular problems as any type of butter can be used to make toffee. 

The remaining water is finely distributed across the fat phase by a kneading or extrusion process. During this phase aroma compormds, for example, lactic acid fermentation extracts, can be added to modify the taste profile in case sweet cream was used to produce the butter. 

Other inventions that assisted in the development of the butter industry included the Babcock test (1890), which accurately determines the percentage of fat in milk and cream the use of pasteurization to maintain milk and cream quality the use of pure cultures of lactic acid bacteria and refrigeration to help preserve cream quality. 

The flavor of the cream may be enhanced by culturing, adding food-grade lactic acid bacteria, or adding natural flavors obtained by distilling a fermented milk cream may also be added to the finished butter. In addition, color, derived from an FDA-approved source, may be used (61). 

Bertrand, 1994 Allen, 1995) decanal and ( )-2-nonenal, on the other hand, are associated with sawdust or plank odour (Chatonnet and Dubourdieu, 1996 1998). The principal carbonyl compound formed in MLF is 2,3-butanedione (diacetyl), whose level can improve, or affect, the wine with its butter-like or fat note (Davis et al., 1985). Diacetyl and 3-hydroxy-2-butanone (acetoin, the reduced form of diacetyl) are produced by pyruvate metabolism of yeasts and lactic bacteria, and their levels may increase two or three fold with MLF depending on the lactic bacteria strain involved (Davis et al., 1985 Martineau and Henick-Kling, 1995 Radler, 1962 Fornachon and Lloyd, 1965 Rankine et al., 1969 Mascarenhas, 1984). For diacetyl in wine sensory thresholds ranging from 0.2mg/L (in Cbardonnay) to 0.9mg/L (Pinot noir), and 2.8 mg/L (Cabernet Sauvignon wine), are reported (Martineau et al., 1995). 

Further typical applications in the field of dairy products are the determination of sodium in butter, and the analysis of organic acids such as lactic acid, pyruvic acid, and citric acid in cheese products. The latter is performed after appropriate sample preparation via ion-exchange chromatography. 

The inhibition of the enzyme tyrosinase may very well be a key to the control of melanoma, and some of the known inhibitors include eommon substances. Thus, vitamin C, among other common and uncommon substances, has been listed as an enzyme inhibitor for tyrosinase in M.K. Jain s Handbook of Enzyme Inhibitors, 1965-1977 (1982). In addition to ascorbic acid (vitamin C), these other substances include the following halide ion (e.g., from the chloride of common salt, or from iodides and fluorides) butyric acid (from rancid butter) lactic acid (the end product of cancer cell metabolism, found naturally in sour milk products) oxalic acid (ordinarily considered toxic, although it occurs naturally in rhubarb and wood sorrel, etc.) formic acid (a component of ant stings) tyrosine itself and deadly cyanide (which is a chemically bound component of laetrile), as found in almonds (notably bitter almonds), in apricot seeds, and in certain legumes such as beans, etc., although the heat from cooking may drive off the cyanide content. 

The Sigma catalog lists tyrosinase, the enzyme involved in melanoma. As mentioned elsewhere, among the inhibitors listed in the handbooks of enzyme inhibitors are ascorbic acid, or vitamin C, halide ion (the halides being chlorides, notably, but also fluorides, bromides, and iodides), butyric acid (a component of rancid butter), lactic acid (the final product of anaerobic glycolysis, as occurs in cancer cell metabolism, and a component also of sour milk and buttermilk), oxalic acid (e.g., as found in rhubarb and in wood sorrel), formic acid (a component of ant stings), even tyrosine itself, and toxic cyanide ion. And, as has been indicated, alpine sunflower/yueea extract may possibly serve as an enzyme inhibitor for tyrosinase. 

With regard to melanoma, which involves the enzyme tyrosinase, there are a number of inhibitors listed in the handbooks for this particular enzyme. Among them, interestingly, is ascorbic acid, or vitamin C, as well as some other commonly encountered substances such as lactic acid (from sour milk products) and butyric acid (from rancid butter). The aforecited alpine sunflower/yucca extract developed by Owen Asplund of the University of Wyonming may very well act as an enzyme inhibitor for tyrosinase. 

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