A study was conducted to investigate the use of bacterial numbers and metabolites for their Value in predicting potential shelf-life of pasteurized fluid milk. The study consisted of two phases. In the first phase, chemical inhibitors were evaluated for their ability to allow growth of gram-negative psychrotrophic bacteria while inhibiting growth of gram-positive organisms. Crystal violet, benzalkonium chloride, a mixture of crystal violet and benzalkonium chloride, and alkylaryl sulfonate were tested. These were incubated with milk samples separately inoculated with gram-negative and gram-positive bacteria, at 2l°C for 18 hours. Alkylaryl sulfonate allowed growth of gram-positive organisms. Crystal violet inhibited gram-positive organisms but was not as effective as the mixture of crystal violet and benzalkonium chloride, The inhibitor of choice was benzalkonium chloride as it inhibited growth of all gram-positive organisms tested and allowed growth of the gram-negative psychrotrophic organisms. / Master of Science
Identifer | oai:union.ndltd.org:VTETD/oai:vtechworks.lib.vt.edu:10919/45943 |
Date | 21 November 2012 |
Creators | Byrne, Robert Duane |
Contributors | Food Science and Technology, Bishop, J. Russell, Eigel, William N. III, Jones, Gerald M. |
Publisher | Virginia Tech |
Source Sets | Virginia Tech Theses and Dissertation |
Language | English |
Detected Language | English |
Type | Thesis, Text |
Format | viii, 51 leaves, BTD, application/pdf, application/pdf |
Rights | In Copyright, http://rightsstatements.org/vocab/InC/1.0/ |
Relation | OCLC# 21188564, LD5655.V855_1989.B976.pdf |
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