Author : Samuel Henry Ayers
Publisher : Forgotten Books
ISBN 13 : 9780365325376
Total Pages : 20 pages
Book Rating : 4.3/5 (253 download)
Book Synopsis The Determination of Bacteria in Ice Cream (Classic Reprint) by : Samuel Henry Ayers
Download or read book The Determination of Bacteria in Ice Cream (Classic Reprint) written by Samuel Henry Ayers and published by Forgotten Books. This book was released on 2018-03-22 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from The Determination of Bacteria in Ice Cream The method of collecting samples and making bacterial counts used in our experiments gives results which indicate that bacteria in commercial ice cream are distributed quite evenly and that an analysis of one sample from a gallon of ice cream gives results which will hold for any other similar sample from the same gallon. Storage of ice cream for 11 days in a commercial ice-cream cabinet or in a hardening room for a period of two months did not seem to cause an uneven distribution of bacteria. In a series of from 5 to 10 samples taken directly from a large commercial freezer the bacterial counts on each sample checked within the usual limits of error of bacterial analyses. No greater variation in bacterial counts between samples was observed when the plates were incubated at 37 C. (986° F.) for 48 hours than when incubated at 30° C. (86° F.) for a period of five days. When dilutions were such that about 200 colonies were present on the plates a lower variation between counts of samples of ice cream was found than when there were 50 or fewer colonies per plate. The variation between a series of plates made from the same sample and dilution was found to range from 7 to per cent. Among du plicate plates a variation as high as 41 per cent was observed. This must be remembered in connection with the fact that the variation found in our experiments between average counts of different samples of ice cream from the same gallon lot ranged, generally speaking, between 20 and 30 per cent. To this variation between duplicate plates or a series of plates from the same dilution must be added the error introduced in removing 1 c. 0. Portions of ice cream from different samples. When interpreting bacterial counts, differences in the number of bacteria per cubic centimeter should never be considered except in relation to the total count of each sample. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art technology to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.
