Bacteria in milk and its products : designed for the use of students in dairying and for all others concerned in the handling of milk, butter or cheese

Abstract

Successful dairying at the present time depends, to a very large extent, upon skill in handling bacteria. It is impossible to meet the present conditions of the city milk supply, of butter-making and cheese manufacture, without a knowledge of the relation of these microscopic organisms. Bacteriology has become, therefore, a necessary part of dairy courses. The subject is, however, equally important in other directions.The demonstrated connection between milk bacteria and the distribution of certain diseases has brought the subject of bacteria of milk products forcibly to the attention of boards of health and sanitarians. To meet the needs of such persons and all others interested in the handling of milk is the purpose of this work.Most of the facts given in the following pages have been published in scientific papers which have appeared in the last ten years. Some of them, however, are the result of personal investigations not as yet published. A list of the more important recent references to literature upon milk bacteria is given at the close of the text. Wherever it seemed to be necessary references to this literature have been inserted in the body of the text.In the last chapter are given the methods of bacteriological analysis in use at the present time, but, since some of these are admittedly unsatisfactory in certain respects, it is quite likely they may be replaced by better ones in the near future.The growing appreciation of the necessity of bacteriological study of market milk has made it desirable to insert careful directions for laboratory work, even though recognizing that these may not long remain the best methods of laboratory technique.Middletown, January, 1903. the board that gives the certificate. In spite of these imperfections, however, there is no doubt that the person who purchases certified milk will obtain milk which, in general, is INDEX. Abnormal cheese ripening, 240 Acidity of milk, determination of, 286 Actinomyces, 24 Adulterations, 150 Aeration, 54 Aerobic bacteria, 29 Air, a source of bacteria, 43 Alcoholic fermentation, 91