Incidence of Bacillus cereus in Milk and Some Milk Products

Abstract

Four hundred samples of milk and milk products were obtained over a 5-month period from different retail outlets in Madison, Wisconsin, and were examined for presence and number of Bacillus cereus. B. cereus was isolated from 9,35, 14 and 48% of raw milk, pasteurized milk, Cheddar cheese and ice cream samples, respectively. No. B. cereus was recovered from yogurt. The level of contamination with B. cereus did not exceed 100/ml in raw milk, 1000/ml in pasteurized milk, 200/g in Cheddar cheese and 3800/g in ice cream.

Bacillus cereus food poisoning: international and Indian perspective

“…Its spores and vegetative forms are frequent inhabitants of many food types, especially cereals and its derivatives (Barkley and Delaney 1980) rice, vegetables (Portnoy et al 1976); spices, herbs and additives (Baxter and Holzapfel 1982). These forms are also present in milk and dairy products (Ahmed et al 1983), raw meat, eggs, and processed foods (Goepfert et al 1972) as well as in ready to eat food stuffs (Kramer and Gilbert 1989). It forms resistant spores and spreads easily, therefore there is a risk in its transmission through processed, pasteurized, sterilized, and heat-treated food products (Kotiranta et al 2000).…”

“…cereus is considered to be a common contaminant of raw milk and has been reported since 1916 (Ahmed et al 1983). Most of the B. cereus contamination results from the raw milk in which the organism is partly present as spores and able to survive pasteurization.…”

“…El-Naway et al (1982) found each of 70 samples of market milk, scalded cream and Domiati cheese contained B. cereus, with average cell counts of 2.55×10 2 , 6.70×10 2 and 2.40× 10 3 /g, respectively. Ahmed et al (1983) analyzed 400 samples of milk and milk products over a 5-month period from different retail outlets in Madison, Wisconsin and isolated B. cereus from 9, 35, 14 and 48 % of raw milk, pasteurized milk, Cheddar cheese and ice cream samples respectively.…”

Ocorrência de Bacillus cereus em leite integral e capacidade enterotoxigênica das cepas isoladas

“…Christiansson et al (1999) e Vidal-Martins (2005) realizaram estudos sobre a sobrevivência do microrganismo e verificaram que o DNA de B. cereus, isolados antes e após o processamento térmico do leite, apresentaram semelhança genética. Ahmed et al (1983) analisaram amostras de leite cru e pasteurizado e verificaram que as taxas de contaminação foram de 9 e 35%, respectivamente, indicando uma provável contaminação pós-pasteurização. B. cereus é um agente formador de biofilmes, fato que pode explicar o aumento da taxa de contaminação do leite.…”

Avaliação dos efeitos da radiação ionizante nos aspectos microbiológicos, físico-químicos e sensoriais de sorvetes

“…Isso acontece, pois o sorvete é um excelente meio para crescimento microbiológico devido à sua composição, pH geralmente neutro (6 a 7) e longo período de armazenamento (KANBAKNA et al, 2004;JO et al, 2007 et al, 1983;ANON, 1986;PALUMBO, 1986;WHO, 1988;de CENTORBI et al, 1989;KAMAT et al, 1989;ANON, 1990a, b;GREENWOOD et al, 1991;SALEH et al, 1993;CHAMPAGNE et al, 1994;ANON, 1997;PEDNEKAR et al, 1997 …”