EFFECTIVE METHOD FOR DRY INOCULATION of BACTERIAL CULTURES

摘要

An effective way for inoculation of bacteria into dry foods/ingredients that gives a uniform mixture was developed. In the first part of this experiment,Salmonella typhimuriumwas successfully inoculated into chalk. Chalk tubes were weighed then soaked in a broth withS. typhimuriumand allowed to dry back to their original weight. the dried chalk was made into a powder form. A viable cell count of this chalk, using a selective media forS. typhimurium, showed that the organism survived the drying while entrapped in the chalk. the “charged” chalk was used in an experiment as a dry inoculum where it was mixed with a low‐moisture poultry feed. In comparison to a liquid inoculum, the “charged” chalk was a superior way of inoculating into dry particles because it created a more homogenous mixture with the feed without altering any properties of the feed itself. the second part of this experiment entailed a shelf‐life study of the “charged” chalk. the same procedures for inoculating chalk were done using ten different cultures includingBacillus cereus, Clostridium perfringens, Escherichia coli, Enterobacter aerogenes, Lactobacillus plantarum, Listeria monocytogenes, Pseudomonas aeruginosa, Salmonella typhimurium, Staphylococcus aureus, andStreptococcus faecalis.Data showed that the cultures are stable in the chalk for at l