Butter churning

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. 

Butter. In the United States about 10 wt % of edible fats used are butter. Butter is defined as a product that contains 80% milk fat with not more than 16% moisture. It is made of cream with 25—40% milk fat. The process is primarily a mechanical one in which the cream, an emulsion of fat-in-semm, is changed to butter, an emulsion of semm-in-fat. The process is accompHshed by churning or by a continuous operation with automatic controls. Some physical properties are given in Table 16 (see Emulsions). 

Buttermilk. Buttermilk is drained from butter (chum) after butter granules are formed as such, it is the fluid other than the fat which is removed by churning. Buttermilk may be used as a beverage or may be dried and used for baking. Buttermilk from churning is - 91% water and 9% total sohds. Total sohds include lactose [598-82-3] 4.5% nitrogenous matter, 3.4% ash, 0.7% and fat, 0.4%. Table 17 gives the U.S. specifications for dry buttermilk (DBM) and whey. 

Butter-amylester, tn. amyl butyrate, -ather, tn. butyric ether (ethyl butyrate), -baum, tn. shea tree, -blume, /. buttercup, -farbe, /. butter color, -fass, n. churn, -fett, n. butter fat butyrin. -gMrung, /. butyric fermentation. -gelb, n. butter yellow. 

The milk and cream in ice cream contain butterfat, proteins, and milk sugars. Butterfat adds rich flavor, smooth texture, body, and good melting properties. The triglycerides in butterfat melt over a wide range of temperatures, so there is always some bit of solid and some liquid butterfat. Some of the butterfat almost turns into butter while the ice cream is being churned, adding to the unique texture of ice cream. 

Often the leaves of C. sinensis are prepared in a very unique manner, such as in Tibet, where, for example, tea leaves are boiled overnight on an open fire, with a pinch of alkaline soda added. After the tea is strained, yak butter and salt are added and the concoction is vigorously pumped in a churn to a frothy brew. The tea is then poured back into the pot, reheated and served. 

In order to determine whether there was sufficient DDT in the milk to produce effects in rats, milk from the cows was separated and the cream was incorporated into a synthetic diet which was fed to a group of rats for a period of 4 months. Butter was churned from some of the cream and this was likewise incorporated into a diet and was fed to another group of rats. These data will be published elsewhere. 

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 mechanical breaking of colloids is also essential when making butter from milk the solid from soured cream is churned extensively until phase separation occurs. The water-based liquid is drained away to yield a fat-rich solid, the butter. 

From the milk ocean of her blessing good butter is churned Which worthy ones receive as glory. 

Most creamery butter is produced by churning sweet cream so that the fat globules coalesce into a soft mass. The federal standard for butter (USDA 1981B) requires not less than 80% milk fat. FAO/WHO standards specify 80% milk fat, as well as no more than 16% water and a maximum of 2.0% nonfat milk solids (FAO 1973). The required fat level is universal. A typical analysis of butter is given in Table 2.3. Whey butter has a similar composition but is derived from the milk fat recovered from cheese whey. 

Mulder and Walstra (1974) have compiled a list of the factors which influence the crystallization of milk fat. The amount of solid fat is directly affected, with considerable relevance to the isolation of milk fat, as per churning and the structure of butter. 

Historically, butter has been produced by churning chilled cream until the oil-in-water (O/W) milk fat emulsion is broken and the milk fat forms butter granules that separate from the aqueous buttermilk phase. Several continuous buttermaking processes are now available to manufacture butter (Brunner 1974 Harper and Seiberling 1976). 

Taste is only one of several qualities of a process or product that is affected by an excess of either of these 10ns. Some raw materials are naturally too acidic, others too alkaline—so that neutralizers must be added to adjust the pH within an acceptable range. In die dairy industry, for example, the acid in sour cream must be adjusted by the addition of alkaline compounds in order that satisfactory butter can be churned. Quite often, the pH may be difficult to adjust or to maintain after adjustment. Stability of pH can be accomplished by the addition of buffering agents that, within limits, effectively maintain the desired pH even when additional acid or alkali is added. For example, orange-flavored instant breakfast drink has just... 

It is often necessary to process food before it is suitable for human consumption. Grain must be ground into flour, milk churned into butter, barley and hops brewed into beer, for example. Simple contamination might arise from direct contact with containers and tools used in food processing if they are not made from suitable materials. Machinery lubricants and coolants sometime leak and they can find their way into food. 

This is the liquid product remaining after whole milk is churned and the butter removed. It usually contains more fat than skim milk. Buttermilk is more acidic than skim milk and can have more of a laxative action. It is an excellent source of supplemental protein. 

Dolby, R.M. 1954. The effect of temperature treatment of cream before churning on the consistency of butter. J. Dairy Res. 21, 67-77. 

Kapsalis, J.G., Kristoffersen, T., Gould, I.A., Betscher, J.J. 1963. Effect of chemical additives on the spreading quality of butter. II. Laboratory and plant churnings. J. Dairy Sci. 46, 107-113. 

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