Nichols G L, Little C L, Mithani V, de Louvois J
Environmental Surveillance Unit, Public Health Laboratory Service, Communicable Disease Surveillance Centre, London, UK.
J Food Prot. 1999 Aug;62(8):877-82. doi: 10.4315/0362-028x-62.8.877.
The microbiological quality of 4,162 samples of cooked rice from restaurants and take-away premises in the United Kingdom was examined, including ready-to-eat rice purchased at point-of-sale and rice that was stored precooked for reheating on demand. The majority of point-of-sale cooked rice samples (1,855 of 1,972; 94%) were of acceptable microbiological quality, but 15 (1%) samples were of unacceptable quality (Bacillus spp. and B. cereus, > or = 10(5) CFU/g; Escherichia coli, > or = 10(4) CFU/g), indicating a potential risk to health. The prevalence of Bacillus spp., B. cereus, and E. coli was significantly greater in precooked stored rice than in point-of-sale cooked rice (P < 0.005 to 0.0005). Bacillus spp. (> or = 10(4) CFU/g), B. cereus (> or = 10(4) CFU/g), and E. coli (> or = 10(2) CFU/g) were present in 7%, 2%, and 9% of precooked stored samples, respectively, compared to 2%, 0.5%, and 1%, respectively in point-of-sale samples. Although final heating at the point of sale reduces the levels of microorganisms present in rice it will not inactivate the B. cereus emetic toxin if present. Rice from Indian premises was of poorer microbiological quality than that from Chinese and other premises. Although most point-of-sale cooked rice samples (94%) were of an acceptable microbiological quality, evidence from this study indicates that the microbiological quality of cooked rice sold from certain outlets in the UK is of concern.
对英国餐厅和外卖店的4162份米饭样本的微生物质量进行了检测,包括在销售点购买的即食米饭以及预先煮熟储存以便按需重新加热的米饭。大多数销售点的熟米饭样本(1972份中的1855份,占94%)微生物质量合格,但有15份(占1%)样本质量不合格(芽孢杆菌属和蜡样芽孢杆菌,≥10⁵CFU/g;大肠杆菌,≥10⁴CFU/g),表明存在健康风险。预先煮熟储存的米饭中芽孢杆菌属、蜡样芽孢杆菌和大肠杆菌的检出率显著高于销售点的熟米饭(P<0.005至0.0005)。预先煮熟储存的样本中,分别有7%、2%和9%含有芽孢杆菌属(≥10⁴CFU/g)、蜡样芽孢杆菌(≥10⁴CFU/g)和大肠杆菌(≥10²CFU/g),而销售点样本中的比例分别为2%、0.5%和1%。尽管在销售点的最终加热会降低米饭中微生物的含量,但如果存在蜡样芽孢杆菌呕吐毒素,加热并不能使其失活。来自印度餐厅的米饭微生物质量比来自中国餐厅和其他餐厅的米饭差。尽管大多数销售点的熟米饭样本(94%)微生物质量合格,但本研究的证据表明,英国某些销售点出售的熟米饭的微生物质量令人担忧。