. Bacteriological methods in food and drug laboratories, with an introduction to micro-analytical methods. Bacteriology; Food; Drug adulteration; Bacteriology. Fig. 52.—Phytosterol crystals. Fig. 53.—Cholesterol crystals. fin oil, if present, are likewise separated by this treatment. The combined filtrate and washings are next cooled to a temperature of io° to 120 C. and allowed to stand at that temperature for 2 to 3 hr. During this time the acetates of cholesterol and phytosterol crystallize from the solution. They are removed by filtra- tion, washed with cold 80 per cent, alcohol, and then
. Bacteriological methods in food and drug laboratories, with an introduction to micro-analytical methods. Bacteriology; Food; Drug adulteration; Bacteriology. Fig. 52.—Phytosterol crystals. Fig. 53.—Cholesterol crystals. fin oil, if present, are likewise separated by this treatment. The combined filtrate and washings are next cooled to a temperature of io° to 120 C. and allowed to stand at that temperature for 2 to 3 hr. During this time the acetates of cholesterol and phytosterol crystallize from the solution. They are removed by filtra- tion, washed with cold 80 per cent, alcohol, and then dissolved on the filter with a stream of hot absolute alcohol from a wash bottle, as little alcohol as possible being used. The alcoholic solution of the acetates is caught in a small glass evaporating dish, two or three drops of distilled water being added to the solution and heat applied if it is not perfectly clear. The dish is then set out on a desk in the laboratory and the alcohol allowed to evaporate spontaneously. The contents are stirred occasionally and the deposit of crystals which forms around the edges of the liquid and on the sides of the dish rubbed down into the solution with the stirring rod. As soon as a good deposit of crystals has formed they are removed by filtering through a hardened. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Schneider, Albert, 1863-1928. Philadelphia, P. Blakiston's Son & Co
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Keywords: ., bo, bookcentury1900, bookdecade1910, booksubjectfood, bookyear1915