BACTERIA IN THE INDUSTRIES. 109 



induced by the mixed and often filthy "yeasts" employed in making koumys, 

 kefir, yoghurt, matzoon and other similar fermented milk foods, are superior 

 or inferior to those of lactone and other pure culture milk ferments^ It is, 

 however, very evident that the marketed preparations in tablet form give 

 very satisfactory results, as used by pharmacists and in the home. Full 

 directions for using the tablets are found on every package. As is natu- 

 rally to be supposed, these tablets deteriorate in a comparatively short time 

 and all reliable manufacturers place the age-limit on each package. 



Pharmacists can prepare a marketable kefir ferment powder from milk 

 activated by kefir, provided care is observed to guard against outside infec- 

 tion in the several steps of procedure. The following is the method of pre- 

 paring a kefir powder: 



A. Securing the Kefir. The kefir known as kefir grains or kefir seeds 

 may be secured from the large dealers in drugs in New York City or in 

 other large Eastern port cities. The kefir is a solid of a tough gelatinous 

 consistency, brittle when dry, of grayish-yellow color. It is a conglomera- 

 tion of various organisms, as Dispora caucasica, several species of other 

 microbes, a yeast organism, and other undetermined organisms. 



B. Washing the Kefir. Place two or three drams of the kefir in a mixture 

 of equal parts of milk and water, enough to cover the kefir. Allow to stand 

 for four hours, decant off the liquid and renew at intervals of about one hour. 

 Repeat this four or five times at a temperature of about 82 F. 



This process serves a cleansing purpose and initiates the fermentative 

 change. The amount used will depend upon the quantity of powder to be 

 made. 



C. Preparing the New Kefir. Wrap the washed and softened kefir in a 

 piece of sterilized gauze and place it in one quart of pasteurized milk. Keep 

 at a temperature of 82 F. Allow to stand for from twelve to fifteen hours, 

 until the milk is curdled. 



D. Skimming and Draining the Kefir. Remove the cream and drain the 

 curd (kefir) in sterilized gauze until quite dry. 



E. Drying. Add (to the drained kefirized curd) an equal weight of 

 sugar of milk, mix, and spread thinly upon sterilized gauze or upon a sterile 

 glass plate and dry in a current of sterile warm air (80 F.) 



F. Powdering. Powder the dried mass gently and put up in dry, sterile, 

 one-ounce, wide-mouthed vials, closed with sterilized corks. 



G. Directions for Use. Upon the bottles place the following directions 

 for using the powder thus prepared: "Dilute one quart of milk with one- 

 half pint of water, add a pinch of salt and one level teaspoonful of the powder. 

 Set aside for twelve to fifteen hours at a temperature of 85 F., shaking 

 frequently. Use at once or keep on ice." 



There are, of course, no conveniences for regulating the temperature in 



