Kikoku Yutaka, Tagashira Nobuhiro, Nakano Hiroyuki
Graduate School of Biosphere Science, Hiroshima University, 1-4-4 Kagamiyama, Higashi-hiroshima-shi, Hiroshima 739-8528, Japan.
J Food Prot. 2008 Oct;71(10):2030-5. doi: 10.4315/0362-028x-71.10.2030.
This study dealt with the isolation, characterization, and identification of the fungal microflora of frozen blueberries imported from Canada. The thermal inactivation rates of the rarely studied isolated heat-resistant molds, Devriesia spp. and Hamigera striata, in naturally and artificially contaminated blueberry slurries were also determined. The D-values of naturally contaminating Devriesia spp. at 70, 80, 85, and 90 degrees C were 714, 114, 44.4, and 14.1 min, respectively. The D-values of H. striata at 70, 80, 85, and 90 degrees C were 909, 286, 42.6, and 10.3 min, respectively. The z-values calculated from the thermal death time curves were 11.0 and 6.9 degrees C for Devriesia spp. and H. striata, respectively. Results also showed that in both test mold species, the naturally occurring molds had significantly higher thermal resistance than did the artificially contaminated counterparts. The results established by this study may be used by blueberry processors to prevent losses due to spoilage caused by the heat-resistant microorganisms.
本研究涉及从加拿大进口的冷冻蓝莓中真菌微生物区系的分离、特性分析和鉴定。还测定了鲜少研究的分离出的耐热霉菌——德弗里斯霉菌属（Devriesia spp.）和条纹哈米霉菌（Hamigera striata）在天然和人工污染的蓝莓浆中的热失活率。天然污染的德弗里斯霉菌属在70、80、85和90摄氏度下的D值分别为714、114、44.4和14.1分钟。条纹哈米霉菌在70、80、85和90摄氏度下的D值分别为909、286、42.6和10.3分钟。根据热致死时间曲线计算得出，德弗里斯霉菌属和条纹哈米霉菌的z值分别为11.0和6.9摄氏度。结果还表明，在两种受试霉菌中，天然存在的霉菌比人工污染的霉菌具有显著更高的热抗性。本研究得出的结果可供蓝莓加工商用于防止因耐热微生物导致的腐败造成的损失。
