Ripening process of butter

The thermal treatment of the cream, also known as ripening, is the most time-consuming step in butter production; however, it governs the crystallization of the fat and thereafter the consistency of the butter.

Ripening is needed for production of desirable flavor and aroma in butter; also facilitates exhaustive churning. Ripening improves the keeping quality of un-salted butter but reduces the keeping quality of salted butter.

Ripening involves addition of starter culture, mixing it thoroughly and storing the cream (incubating) at controlled temperature. Traditionally cream for ripened cream butter is fermented by selected lactic acid bacteria, which produce lactic acid from lactose and diacetyl (principal flavouring component in ripened cream butter) from citric acid.

Starter culture consisting of a mixture of both acid producing (Streptococcus lactis, S.cremories) and flavour producing (S.diacetylactis, Leuconostoc citrovorum and/or Leuc. dextranicum) organisms is added. Amount of starter added depends on several factors and usually ranges between 0.5-2.0 percent of the weight of the cream.

The cream is ripened to pH 5.5 at 21°C and then pH 4.6 at 13°C to arrest further acid development. Most flavor development occurs between pH 5.5 - 4.6. Biosynthesis of diacetyl is not sufficient above pH 5.5.

The colder the temperature during ripening the more the flavor development relative to acid production. Ripened butter is usually not washed or salted.
Ripening process of butter

Butter processing: Pasteurization

The pasteurization of cream for butter making has for its primary object the elimination of the normal bacteria of the cream to enable the butter maker by controlling the ripening of the cream to secure a uniform product.

Butter processing begins with the clarification and separation of milk. The cream is cooled and kept in a transitional storage tank where the fat content is analyzed, and if necessary adjusted to the desired value.

Cream with a concentration of 30 to 45 percent milkfat (depending on the method of churning) is then pasteurized and cooled.

For vat pasteurization the cream is normally pasteurized at 74° C for 30 minutes; for the high temperature short time method cream is pasteurized at 85° C for 15 seconds.

The high temperature is needed to destroy enzymes and micro-organisms that would impair the keeping quality of the butter and to help lengthen butter’s shelf life.

Pasteurization of cream for making ripened cream butter is commonly carried out at higher temperature than for sweet cream butter e.g., 90-95° C for 15 or 105-110° C with no holding. Severe heat treatment denatures whey proteins, particularly lactoglobulins, exposing-SH groups which act as antioxidants and can enhance starter growth.

Several factors are involved in the determination of this temperature, among the most important of which are the uniform destruction of a large proportion of the bacteria of the cream; the destruction of the enzymes inherent in the milk; the avoidance of imparting scorched, metallic, or other undesirable flavors to the cream; and the possible increased loss of fat in the buttermilk.

Pasteurization causes the fat in the fat globules to liquefy. And when the cream is subsequently cooled a proportion of the fat will crystallize. If cooling is rapid, the crystals will be many and small; if gradual the yield will be fewer but larger crystals.

By modifying the cooling program for the cream, it is possible to regulate the size of the crystals in the fat globules and in this way influence both the magnitude and the nature of the important continuous fat phase.
Butter processing: Pasteurization

Churning process

Butter is essentially milk fat made from milk, dahi (curd) or cream by agitating or shaking it until the fat separates as semisolid mass from the liquid portion (serum) of milk.

The separated milk fat is known as butter, while the watery portion as buttermilk. The process of agitation/ shaking is known as churning and the device used for the purpose is butter churn.

From the aging tank, the cream is pumped to the churn or continuous butter maker via a plate heat exchanger, which brings it to the requisite temperature. A butter churn is a device used to make butter by shaking up the whole milk (or cream). Butter grains are formed by breaking down the membranes that surround the fat.

Optimum churning temperature: 9-11°C. In the churning process, the cream is violently agitated for 5-10 min to break down the fat globules, causing the fat to coagulate into butter grains, while the fat content of the remaining liquid (buttermilk) decreases.

Churning causes these grains to fuse with each other and form the butter. The liquid that is left out without fat is called buttermilk.
Churning process

What are the characteristics of butter?

Butter is one of the main fat products used as spreads. Both of these products are water in oil emulsions.

Butter usually contains about 80% fat. In England, butter must not contain more than 16% water.

Other constituents of butter include protein (1%), lactose (0.4%), mill ash (0.15%), and salt.

The natural color of butter is due to carotene and other fat soluble pigments.

The major proportion of the butter consumed in many countries is sweet cream butter. That is butter manufactured from fresh cream.

Lactic butter, which is more popular is some other countries is manufactured from cream which is first cultured to develop aromatic flavored compounds, e.g. diacetyl.

Both types of butter may be slated (up to 2% salt) depending on market requirements.

Production of butter
Butter making is synonymous with churning of cream in batch or in continuous buttermakers, the latter having been established since the 1930s.

While both processes have been optimized over the years, batch churns are mainly used in smaller dairies and cheese factories (where the cream recovered from whey is churned into whey butter)and continuous plants are used in large scale operations productions 1 – 4 ton of butter.

What are the characteristics of butter?

Processing of buttermilk

Natural buttermilk is a byproduct of butter manufacture and is categorized as sweet (non-fermented) or acidic (fermented).

Sweet buttermilk is obtained during butter manufacture from pasteurized non-fermented cream. Depending on the processing conditions, which may involve heating the cream before ripening at 90°C for 15 seconds or 105°C- 110°C with no holding, sour cream or sweet cream buttermilk may be produces.

Sweet cream buttermilk can be further fermented by mesophilic lactic acid bacteria.

The basic manufacturing steps of cultured buttermilk involved standardization of the fat and solids-not-fat contents, followed by homogenization heating (85° C for 30 min), fermentation by starter cultures, breaking the fermentate, cooling and packaging. The buttermilk also can be powdered.

Fermented buttermilk contains around 0.7% lactic acid and traces of diacetyl in addition to protein, minerals and about 80% of the non-fermented lactose.

Only a minor percentage of the buttermilk produced is consumed directly, the commercial use of buttermilk includes applications in the baking and dairy industries.
Processing of buttermilk

Processing of Butter

Processing of Butter
Butter is produced by concentrating the milk found in cream, either through churning (causing the fat to flocculate) or through centrifugal processing.

Much of butter manufactured today derives from whey cream. Whey cream has a more pronounced flavor than that of fresh cream and its use is thus favored in lower quality, more flavorful grades of butter. However, it is also commonly used in the production of Grade AA butter.

Butter is often flavored with lactic acid, cultures, diacetyl, or started distillate.

Butter processing begins with the clarification and separation of milk. Cream with a concentration of 30 to 45 percent milkfat (depending on the method of churning) is then pasteurized and cooled.

For vat pasteurization the cream is normally pasteurized at 74 degree Celsius for 30 minutes; for the high temperature short time method cream is pasteurized at 85 degree Celsius for 15 seconds.

These pasteurization temperature are higher than those for fluid milk because of the higher fat content of the cream, and to help lengthen butter’s shelf life.

The cream is not homogenized since that would make churning more difficult.

After the cream is cooled, it is pumped into a conventional churn where it may be mixed with anotto yellow coloring. The cream is then churned until butter granules are formed.

The butter milk is drained and washed from the butter granules, salt is added and the butter is worked to a smooth, creamy consistency.

The butter is then packaged by a print machine, which mold it into sticks, wraps it, and packages it.
Processing of Butter