Buttermilk.
—The residue left in the churn in the manufacture of butter is termed buttermilk. There are two distinct varieties of buttermilk, namely, that resulting from the churning of unsoured cream and that remaining from the churning of soured and ripened cream. The first kind of buttermilk does not differ in its characteristic essentials from skimmed milk and therefore is not considered here. The second class of buttermilk is far more common and is a beverage of pleasing acid taste. When made from properly ripened cream it is wholesome and delicious, especially in summer time. Its composition is that of cream subjected to enzymic action during the ripening process by which an agreeable degree of acidity is produced due to lactic acid, together with the incidental changes which take place in the composition of other parts of the liquid due to enzymic action. Buttermilk also usually contains small particles of butter itself which escape aggregation during the final process of churning. In well prepared buttermilk, however, these particles of butter are not very numerous and they add nothing to the palatability, although they do add something to the nutritive properties of the beverage. The buttermilk represents that portion of milk which is one of the chief constituents of cream as far as bulk is concerned, freed practically from its butter fat. It does not differ greatly, therefore, in its chemical properties from skimmed milk, although there is a slight difference in the relative percentages of the milk solids in cream as compared with the same constituents in whole milk. The composition of buttermilk is shown in the following table:
COMPOSITION OF BUTTERMILK.
| From Sweet Cream. | From Sour Cream. | |
|---|---|---|
| Percent. | Percent. | |
| Water, | 89.74 | 90.93 |
| Fat, | 1.21 | 0.31 |
| Milk sugar, | 4.98 | 4.58 |
| Protein, | 3.28 | 3.37 |
| Ash, | 0.79 | 0.81 |
| Acidity, | ... | 0.80 |
Bonnyclabber.
—Bonnyclabber is a term applied to milk which has become soured by lactic fermentation, producing a gelatinous coagulation of casein which is sufficiently firm at times to prevent the liquid from being poured. Clabber may be regarded as a natural cheese curd except that the fat is chiefly on top. It is a beverage or food of a very agreeable taste to most persons and is often eaten with sugar. In the summer it is often formed during hot murky weather, especially of that character which produces thunder storms. For this reason it is a common supposition that thunder or lightning sours milk. The thunder and lightning, however, have nothing to do with this process. The condition of the atmosphere which produces an environment favorable to electrical disturbances of this kind also favors in the highest degree the growth of the organisms which produce the lactic ferments. Hence thunder storms and the rapid souring of milk are frequently coincident leading to the popular impression as above mentioned. Inasmuch as the souring of milk usually takes place after the cream has risen the composition of clabber is practically that of skimmed milk modified by the lactic fermentation which has taken place.
BUTTER.
When cream, especially cream in which incipient lactic fermentation has been set up, is subjected to agitation in a churn under proper conditions of temperature the particles of butter therein contained are collected into masses so that the butter can be separated from the residual liquid. This process is technically called churning. The domestic churn in its simplest form is perhaps well known to almost everyone, especially those who have lived in the country. In the domestic manufacture of butter the cream is collected and set aside until sour, that is, until lactic fermentation has set up. When this is sufficiently advanced the cream is placed in a churn, the simplest form of which is a wooden, cylindrical vessel of appropriate size, being much longer than its horizontal diameter. The churn is provided with a dasher, namely a perforated wooden disk with a handle which passes through a hole in the cover. When the churn is charged the butter is produced by agitation with the dasher. In winter time warm water is added to the mixture in order to raise the temperature to the proper gathering point of butter, namely 65 to 70 degrees F. For the same reason cold water is added in the summer time. The art of the dairy maid is shown in the proper regulation of the temperature to secure the best results. When the cream is properly ripened and the temperature is suitable the gathering of butter will be accomplished in from twelve to thirty minutes. In unfavorable conditions the duration of churning may be for a much longer period.
Fig. 20.—Power Churn Ready for Use.—(Courtesy of the Bureau of Animal Industry.)