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Bacillus is the strongest stress resistance of the organism in nature , due to its special structure , brought no small trouble to the people 's life and production . The high-pressure the CO2 sterilization technology as a new type of non - thermal sterilization technology , not only can effectively kill vegetative bacteria in food , and also have some role in the killing bacterial spores , and the processing temperature is mild , the damaging effects of heat-sensitive substances in food small , is conducive to maintaining the original quality of the food . In this paper, to achieve high pressure CO2 supercritical state , major to kill Bacillus process of supercritical CO2 (SC-CO2) , synergies and germination agent killing effect , and to investigate the supercritical carbon dioxide to kill the spores mechanism. The main conclusions are as follows: 1) through the single factor experiment to determine the main factors that affect the sterilization process pressure , temperature , and time , by orthogonal test , kill the spores of the optimal process parameters : pressure 20MPa , temperature 35 ℃, the processing time 30min, processed twice , Bacillus killing logarithm value 3.48 . 2 ) as synergist ethanol and H2O2 kill the spores have better synergy , which add 0.6% H2O2 Bacillus killing logarithm value of 4.85 , while little synergy of isopropyl alcohol to kill the spores ; add as the spores germinate agent L-alanine and glucose , the germination of spores in the ambient temperature and pressure have some role , but treated with SC-CO2 the experimental group of L-alanine to be higher than the lethality rate of the experimental group of glucose added , the added concentration of 100mmol / L of L-alanine , after SC-CO2 treatment , Bacillus killing logarithm value of 4.05. ) was found on the treated and untreated spores observed by scanning electron microscopy (SEM) after SC-CO2 treated spores, partially changed morphology , mechanical damage caused by the pressure led to the death of some of the spores , while SC-CO2 processing the formation of bacteria suspended the group , thereby increasing the difficulty of the kill , resulting in sterilization is not thorough enough . 4 ) through the detection of Bacillus protein, nucleic acid spillage found that , even after processing of the SC-CO2 , Bacillus inclusions have leaked , but the effect of the lower pressure and temperature , the leakage amount of the inclusions is also more less the , directly kill caused by supercritical mechanical Bacillus weak . Improve spore germination rate is a kill Bacillus key .
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