Simpson M V, Smith J P, Dodds K, Ramaswamy H S, Blanchfield B, Simpson B K
Department of Food Science and Agricultural Chemistry, McGill University (Macdonald Campus), 21,111 Lakeshore Road, Ste. Anne de Bellevue, Quebec H9X 3V9, Canada.
Bureau of Microbial Hazards, Health Protection Branch, Tunney's Pasture, Ottawa, Ontario, K1A 0L2, Canada.
J Food Prot. 1995 Mar;58(3):229-234. doi: 10.4315/0362-028X-58.3.229.
Challenge studies were carried out to evaluate the safety of a reformulated sous-vide processed spaghetti and meat-sauce product (a 0.992-0.972, pH 4.5-6) inoculated with Clostridium botulinum types A and B spores. Following processing at 75°C for 36 min (equivalent to a 13 D process for Streptococcus faecium ), samples were stored at 15°C and analyzed at selected time intervals for toxin production and visible signs of spoilage. Toxin was detected in samples of pH > 5.5 after 14-21 days and in products of pH 5.25 after 35 days. Toxin was not detected in any samples of pH < 5.25 within 42 days storage at 15°C. All products of pH 5.75 and 6 were visibly spoiled, i.e., swollen due to CO production, prior to toxigenesis. However, for products of pH 5.5 and 5.25, toxigenesis preceded spoilage. Subsequent studies were done to test the effect of additional salt (1-3% w/w) on the safety of a product of pH 5.5 at mild temperature-abuse storage conditions (i.e., 15°C). Toxin production was not delayed in samples containing < 1.5% added salt, while > 1.5% salt (w/w) prevented toxin production throughout the 42-day storage period at 15°C. Microwave heating of products for 5-10 min at full or half power in a domestic microwave (800 watts) inactivated the preformed toxin in all samples.
开展了挑战性研究，以评估重新配方的真空低温烹饪加工意大利面和肉酱产品（水分活度0.992 - 0.972，pH值4.5 - 6）接种A型和B型肉毒梭菌孢子后的安全性。在75°C下加工36分钟（相当于对粪肠球菌的13D处理）后，将样品储存在15°C，并在选定的时间间隔分析毒素产生情况和明显的腐败迹象。在14 - 21天后，pH值> 5.5的样品中检测到毒素，pH值5.25的产品在35天后检测到毒素。在15°C储存42天内，pH值< 5.25的任何样品中均未检测到毒素。所有pH值5.75和6的产品在产毒之前均出现明显腐败，即因产生二氧化碳而膨胀。然而，对于pH值5.5和5.25的产品，产毒先于腐败。随后开展研究，测试在温和温度滥用储存条件（即15°C）下额外添加盐（1 - 3% w/w）对pH值5.5产品安全性的影响。添加盐< 1.5%的样品中产毒没有延迟，而> 1.5%盐（w/w）可在15°C下42天的储存期内阻止毒素产生。在家庭用微波炉（800瓦）中以全功率或半功率对产品进行5 - 10分钟的微波加热可使所有样品中预先形成的毒素失活。
