Part 14 (1/2)

~Culture vs hoe which has accrued from the use of culture or co the need of closer control of the ripening process, greater attention has been paid to the carrying out of the details In the hands of the better operators, the differences in flavor of butter made with a culture or a natural starter are not ood product under ordinary conditions, an improvement is often secured where a commercial culture is used

~Pasteurization as applied to butter-, is often confounded with the treatment of milk and cream for direct consumption It is unfortunate that the same term is used in connection with the two methods, for they have but little in coer, it is not necessary to observe the stringent precautions that are to be noted in the preservation ofstarter controls at once the ferain, the physical requireent in butter- While a cooked taste is imparted to milk or even cream at about 158 F, it is possible to make butter that shows no perh as 185 or even 195 F This is due to the fact that the fat does not readily take up those substances that give to scalded milk its peculiar flavor

Unless care is taken in the rain or body of the butter may be injured This tendency can be overcome if the ripened crea It is also essential that the heated crea pasteurized

The Danes, ere the first to einning, a te to the prevalence of such diseases as tuberculosis and foot-and-mouth disease, it became necessary to treat all of the skim milk that was returned from the creameries For this purpose the ski been ree of heat is sufficient to destroy the seeds of disease With the use of this higher te apparatus is considerably reduced, but the higher te conditions as to disease

When the system was first introduced in Denmark, two methods of procedure were followed: the whole hly pasteurize it before it was separated, or it was separated first, and the cream pasteurized afterwards In the latter case, it is necessary to heat the skianisms, but this can be quickly done by the use of stea the crearain of the butter In spite of the extra trouble of heating the cream and skim milk separately, thisWith the continual spread of tuberculosis in A to be introduced[169]

~Use of starters in pasteurized and unpasteurized cream~ In order to secure the beneficial results presumably attributable to the use of a starter, natural as well as a pure culture, it should be employed in cream in which the bacteria have first been killed out by pasteurization This is certainly the ical and scientific method and is the way in which the process has been developed in Denmark

Here in this country, the use of pure cultures has been quite rapidly extended, but the systeht measure The increased labor and expense incurred in pasteurizing the creaainst the wide-spread use of the process, but doubtless the h a flavor where the cream was heated as in the unheated product As the deh, quick flavor to one that is so quality, doubtless pasteurization of the crearadually occurring is already evident, although as yet only a small proportion of butter made in this country is now made in this way Where the cream is unheated, a considerable number of species will be found, and even the addition of a pure culture, if that culture is of the lactic acid-producing species, will to some extent control the type of fermentation that occurs Such would not be the case with a culture co type of bacteria Only those forms could thus be used which are especially well suited to development in raw creaenerally eanisrow rapidly in cream and produce a pure cream flavor in the butter

~Purity of commercial starters~ Naturally the butter maker is forced to rely on the laboratory for his commercial starter, and the question will often arise as to the purity and vigor of the various ferments employed

As there is no way for the factory operator to ascertain the actual condition of the starter, except by using the sareatest care should be taken by the manufacturer to insure the absolute purity of the seed used

A bacteriological examination of the various cultures which have been placed on the market not infrequently reveals an impure condition In several cases the writer has found a not inconsiderable nuanism Molds not infrequently are found in cultures put up in the dry form Doubtless the effect of these accidental contaminations is considerably less in the case of a starter coanisorously in milk, and it should be said that these iation

The virility and vigor of the starter is also a fluctuating factor, dependent in part at least, upon the conditions under which the organiserm is cultivated in solutions in which acid cannot be formed in abundance Where the conditions perar was present with a lactic acid-producing species, the vitality of the culture is often i acid Some manufacturers atte carbonate of liation of starters for creaation of a starter for creaical knowledge, whether the starter is of doin or prepared from a pure-culture ferment In any event, it is necessary that the starter should be handled in a way so as to prevent the introduction of foreign bacteria as far as possible It should be re and hout its entire history in a way so as to retain its vitality and vigor uni points should be taken into consideration in growing the starter and transferring it from day to day:

1 If a commercial starter is used, see that it is fresh and that the seal has not been broken If the culture is too old, the larger part of the organisms may have died out before it is transferred, in which case the effect of its addition to the sterilized milk would be of little value

When the comerator pending its use so as to retard as o on in the culture liquid Be careful that the bottle is not exposed to the influence of direct sunlight for in a transparentaction of the sun's rays

2 If a horeatest possible care in selecting the milk that is to be used as a basis for the starter

3 For the propagation and perpetuation of the starter frorown in erm-free as it is possible to secure it For this purpose sterilize some fresh skim-milk in a covered can that has previously been well stea ski the same to 180 F or above for one-half hour or more Steam should not be introduced directly This process destroys all but a few of the ive a cooked flavor to the milk, but will not affect the cream to which the starter is added Dairy supply houses are now introducing the use of starter cans that are specially made for this purpose

4 After the heated milk is cooled down to about 70 or 80 F, it can be inoculated with the desired culture Soating it first in a smaller volu it to a larger ae a

5 After the milk has been inoculated, it should be kept at a temperature that is suitable for the rapid development of the contained bacteria, 65-75 F, which temperature should be kept as unifor the covered can in a vat filled ater The starter cans are often arranged so that te water

6 The starter should not be too thoroughly curdled when it is needed for use, but should be well soured and only partially curdled for it is difficult to break up thoroughly the curd particles if the starter is co creaor of the starter is in all probability stronger when thethan it is after the curd has been formed some time The continued formation of lactic acid kills many of the bacteria and thus weakens the ferhly important that the acidity of the starter should be closely watched

8 Do not refrigerate the starter when it has reached the proper stage of developrowth in the sarain It is preferable to dilute the starter, if it cannot be used when ready, with sufficient freshly sterilized sweet milk to hold the acidity at the proper point and thus keep the bacteria in the starter in a condition which will favor vigorous growth

9 The starter should be propagated fro a small quantity to a new lot of freshly preparedcans should be provided so that one starterprepared

~How long should a starter be propagated?~ No hard-and-fast rule can be given for this, for it depends largely upon how carefully the starter is handled during its propagation If the starter is grown in sterilized milk kept in steamed vessels and is handled with sterile dippers, it is possible to maintain it in a state of relative purity for a considerable period of tiiven, it will soon become infected by the air, and the retention of its purity will depend anisrowths than upon any other factor Experience seems to indicate that pure-culture starters ”run out” sooner than doical methods, to determine with accuracy the actual condition of a starter as to its germ content, still such methods are inapplicable in creaeneral appearance of the starter as determined by taste and smell The supply houses that deal in cultures of this class generally expect to supply a new culture at least every month

~Bacteria in butter~ As ripened cream is necessarily rich in bacteria, it follows that butter will also contain ger amounts, but as butter-fat is not well adapted for bacterial food, the nuerms in butter is usually less than in ripened creaerm life than that made from ripened cream Grotenfelt reports in sweet-cream butter, the so-called ”Paris butter,” only a few bacteria while in acid creaerm content runs from scores to hundreds of thousands