MICROBIOLOGY OF FRESH APPLE AND POTATO PLUGS PRESERVED BY GAS EXCHANGE

SUMMARY: Gas exchange as a means of preservation of fresh disk‐shaped plugs of apples and potatoes at ambient temperatures was studied. Death kinetics of the microorganisms E. coli, St. aureus and CL botolinum were determined. The concurrent effects of the gas on the browning enzyme systems of the products was followed. Gram negative rods in the environment of the test materials were rapidly killed when exposed either to a mixture of ethylene oxide (10%) and carbon dioxide (90%) or to pure sulfur dioxide and sulfur dioxide (50%) air mixtures. Gram positive cocci and the spores of the anaerobes showed somewhat slower rates of destruction under the same conditions. Treatment with pure carbon monoxide, nitrogen or packaging in vacuum achieved considerable freedom from color changes but had no appreciable effect on microorganisms. Copyright © 1969, Wiley Blackwell. All rights reserved