文摘
In the present study, the efficiency of the treatment of radio frequency (RF) combined with nisin against the spores of three strains of Alicyclobacillus from two species was examined with the response surface methods (RSM). The results showed that the combination of RF and nisin was effective on killing Alicyclobacillus acidoterrestris and Alicyclobacillus contaminans spores in kiwi fruit juice. The killing effect increased with the increase of temperature, holding time, and nisin concentration, but the increment was not significant at high levels of temperature and nisin concentration. The killing effect between A. acidoterrestris and A. contaminans strains was different in kiwi fruit juice. The strain with the highest killing effect was DSM 17975T, followed by DSM 3923T and C-ZJB-12-33. The reduction of spore number of DSM 17975T at the central design points of RSM was about 2.4. Under experimental conditions, nisin showed hardly any effect on killing DSM 17975T spores when combined with RF.