Safety issues of raw milk: evaluation of bacteriological and physicochemical characteristics of human milk from a bank in a teaching hospital, focusing on Staphylococcus species

Many infants are nurtured with milk supplied by human banks, whose bacteriological and physical-chemical profiles are a major issue. We investigated the bacteriological and physical-chemical characteristics, as well as genotypic and phenotypic and profiles of Staphylococcus species isolated from 240 samples of breast milk from a bank in a teaching hospital. Dornic acidity of milk revealed that 95.4% (229/240) had acceptable limits (< 8.0 oD). Caloric intake showed a wide variation in cream content (4%), fat (4%) and energy values (559.81 Kcal/L). Staphylococcus (105/186 or 56.5%) and Enterobacter (25/186 or 13.4%) were the most prevalent genera, although other microorganisms were identified, including Klebsiella pneumoniae and Pseudomonas aeruginosa. Amoxicillin/clavulanic acid (125/157 or 79.6%), vancomycin (115/157 or 73.2%), and cephalexin (112/157 or 71.3%) were the most effective antimicrobials. High resistance rates of isolates were found to penicillin G (141/157 or 89.8%), ampicillin (135/157 or 86%), and oxacillin (118/157 or 75.2%). Multidrug resistance to ≥ 3 antimicrobials occurred in 66.2% (123/186) of the isolates. Residues of microbial multiplication inhibitory substances were found in 85% (204/240) of samples. Among the coagulase-positive-CPS and negative-CoNS staphylococci, the mecA gene was detected in 53.3% (8/15) and 75% (30/40), respectively. Genes sea, seb and sec were detected in 20% (3/15) of CPS, while tsst-1 was detected in 13.34% (2/15). In addition, 13.3% (2/15) of S. aureus were toxin-producers. Genes sea, seb and sec were detected in 90% (36/40), 5% (2/40) and 15% (6/40) CoNS, respectively. Enterotoxin production was identified in 5% (2/40) of CoNS. The identification of multidrug-resistant bacteria, staphylococci species toxin-producers harboring methicillin-resistance genes, and residues of microbial multiplication inhibitory substances reinforce the need for a continuous vigilance of milk quality offered to infant consumption by human banks

Microbiological vulnerability of eggs and environmental conditions in conventional and free-range housing systems

Although Brazil is currently the world’s eighth largest egg exporter, the shift of consumers towards free-range eggs may present new sanitary challenges. This study aims to evaluate the microbiological vulnerability of eggs and environmental conditions in a farm certified for both conventional and free-range systems using two standard methods (enterobacteria counting and Salmonella spp. survey). Two high-producing farms were selected for this study, one under both conventional and free-range systems at the same place as the test farm, and another under conventional system only as a control farm. Enterobacteriaceae counts were determined for eggshells; and detection of Salmonella spp. was conducted in eggs, nest box material, feeder, and sponge samples from water dispensers, feeders, production plant, besides water samples from nipple dispensers and artesian well. The average enterobacteria count (log CFUmL-1) was 0.09 for conventional and 1.73 for free-range systems (p < 0.001). While Salmonella spp. was not detected in the conventional system but was present in one feeder and three eggshells from the free-range system. Therefore, the conventional system demonstrated better hygiene-sanitary status than the free-range one. Moreover, controlling food safety should always be considered when improving animal welfare

Assessment of the microbiological quality of pattern minas cheese commercialized in Uberlândia and Patos de Minas, Minas Gerais

O queijo minas padrão é um produto elaborado com leite pasteurizado, fermentado com culturas mesófilas e adição de coalho. Esse queijo passa por um processo de maturação artesanal, possui uma casca firme de cor amarelada e sabor ácido. O presente trabalho avaliou a qualidade microbiológica de queijo minas padrão comercializado em duas microrregiões (Uberlândia e Patos de Minas) da mesorregião do Triângulo Mineiro e Alto Paranaíba do estado de Minas Gerais, Brasil. Foram examinadas 40 amostras de queijo. Os ensaios microbiológicos foram contagens de enterobactérias, Escherichia coli, coliformes a 35 oC, Staphylococcus coagulase positiva e pesquisa de Salmonella spp. Na microrregião de Patos de Minas, os resultados foram de 45%, 35%, 20% e 20% superiores a 103 CFU/g para as contagens de enterobactérias, Escherichia coli, coliformes a 35oC e Staphylococcus coagulase positiva, respectivamente. Cinco por cento das amostras analisadas foram positivas à pesquisa de Salmonella spp. Considerando a microrregião analisada (Uberlândia e Patos de Minas), a conclusão obtida foi que na região estudada, as condições de higiene nas etapas de fabricação, manuseio, transporte e armazenamento do queijo minas padrão são precárias, sendo necessária a implementação de sistemas de Boas Práticas de Fabricação (GMP), incluindo Análise de Perigos e Pontos Críticos de Controle (HACCP).Pattern minas cheese is a product developed with pasteurized milk, fermented with mesophilic cultures, and with the final addition of rennet. This cheese undergoes an artisanal maturation process and possesses a firm shell of yellowish color and striking and acidic flavor. Our study objective was to evaluate the microbiological quality of pattern minas cheese. We collected 40 samples from two micro regions (Uberlândia and Patos de Minas) of the Triângulo Mineiro and Alto Paranaíba mesor regions of the State of Minas Gerais, Brazil. The microbiological test results were recorded as counts of enterobacteria, Escherichia coli, coliforms at 35°C, coagulase-positive Staphylococcus and Salmonella spp. In the Patos de Minas micro region, the results were 45%, 35%, 20%, and 20% higher than 103 CFU/g for the counts of enterobacteria, Escherichia coli, coliforms at 35°C, and Staphylococcus coagulase-positive, respectively. Five percent of the analyzed samples were positive for Salmonella spp. in the Uberlândia micro region. Based on the findings of the microbiota in the cheese analyzed from the micro regions (Uberlândia and Patos de Minas), we concluded that the hygiene conditions in the manufacturing, handling, transport, and storage stages were precarious, requiring the implementation of Good Manufacturing Practices (GMP) systems, including Hazard Analysis and Critical Control Points (HACCP)

Avaliação do teste do anel em leite na vigilância epidemiológica da brucelose bovina em rebanhos e em laticínios

Analisaram-se 464 amostras individuais de leite e 54 amostras de leite de latões, oriundos de leite dos mesmos animais, por meio do teste do anel do leite (TAL) visando à sua aplicação no diagnóstico individual e de rebanhos da brucelose bovina. Foram também avaliadas 464 amostras de soro sangüíneo por meio de provas do antígeno tamponado acidificado (ATA), soroaglutinação lenta em tubos (SAL) e 2-mercaptoetanol (2-ME), todas para brucelose. Cento e vinte e três amostras (26,5%) testadas pelo TAL apresentaram resultados positivos. Dessas, 30 resultaram positivas ao ATA, 28 ao ATA, à SAL e ao 2-ME e 18 à SAL. Das amostras positivas ao TAL, 95 pertenciam a animais sorologicamente negativos ao 2-ME, caracterizando 77,2% (95/123) das reações falso-positivas; dos resultados negativos ao TAL, 4 pertenciam a animais sorologicamente positivos, caracterizando 1,2% (4/341) de reações falso-negativas no TAL individual. Das 54 amostras de leite de latões analisadas pelo TAL, 17 foram consideradas positivas, das quais uma foi caracterizada como falso-positivo, pois todos os animais que a compunham foram negativos ao 2-ME. de 37 latões considerados negativos ao TAL, três continham leite de animais positivos ao 2-ME, caracterizando 8,1% de falso-negativos. O TAL individual demonstrou elevado percentual de resultados falso-positivos, enquanto o TAL em amostras de leite obtidas em latões detectou 84,2% de latões contaminados e 75% de rebanhos infectados.The ring test (RT) was analyzed regarding its application for the individual and herd bovine brucellosis diagnoses. Individual samples of milk from 464 cows and 54 composite samples of milk bucket from these animals were evaluated. The results were analyzed considering the serological results obtained by the rose bengal (RBT), tube agglutination (TAT) and 2-mercaptoethanol (2-ME) tests. From the 464 individual milk samples analyzed by the RT, 123 (26.5%) presented positive results. From those, 30 were positive only to the RBT, 28 by the RBT/TAT/2-ME and 18 by the TAT. From the 123 positive samples by the RT, 95 came from the 2-ME seronegative animals, characterizing 77.2% of false-positive reactions and 4/341 negative reactions came from the seropositive animals, characterizing 1.2% of false-negative reactions in the individual RT. From the 54 samples of compositive milk analyzed by the RT, 17 were positive. From these positive samples, one was considered false positive since all the animals that composed it were negative by the 2-ME. Three of the composite milk samples that were negative to RT(3/37) were constituted by milk from positive animals, characterizing 8.1% of false-negative results by the RT. The individual RT showed high percentage of false-positive results, while the RT in samples from bucket detected 84.2% of the contaminated milk and 75% of the infected herds

Ocorrência de Bacillus cereus em leite comercializado nos estados do Paraná, Santa Catarina e São Paulo

Bacillus cereus is a bacterium that arouses great concern on dairy sector. Its psychrotrophic and thermoduric behavior confers great spoiling potential and its pathogenicity is extremely worrynig to public health. This study evaluated the presence of B. cereus in 260 samples, from which 100 was pasteurized milk, 110 was UHT milk and 50 was milk powder. The techiques used were both quantitative (direct plating) and qualitative (selective enrichment) methods. 19% of pasteurized milk samples evaluated by the quantitative method were positive for B. cereus, with an average contamination of 1.25 (± 0.27) log CFU/ml. For milk powder, 16% of the samples was positive for this microorganism, with an average of 2.00 (± 0.36) log CFU/g. UHT milk samples did not show results within the detection limit of the direct plating method (> 1 log CFU/ml). Regarding the qualitative method, 24% of the pasteurized milk samples, 34% of milk powder and 16.4% of UHT milk was positive for B. cereus. There was no significant difference (P 10 UFC/ml) para nenhuma das amostras avaliadas. Pelo método qualitativo 24% das amostras de leite pasteurizado, 34% de leite em pó e 16,4% de leite UHT foi positiva para B. cereus. Para as amostras de leite pasteurizado e leite em pó não houve diferença significativa (P>0,05) na positividade entre os métodos quantitativo e qualitativo. Os resultados do presente trabalho ressaltam que, mesmo em pequenas quantidades, B. cereus está presente não apenas em leite pasteurizado, mas também em produtos lácteos processados a altas temperaturas (leite UHT) e desidratados (leite em pó).Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq

Use of three rapid detection systems to evaluate the prevalence and dissemination of Salmonella in a Brazilian poultry slaughterhouse

Prevalence and dissemination of Salmonella in a Brazilian poultry slaughterhouse were evaluated by three rapid detection systems (SS/SV(TM), VICAM, OSRT(TM), Unipath/Oxoid, and REVEAL(TM), Neogen), plus the conventional procedure. The carcasses were sampled after bleeding (P1), defeathering (P2), evisceration (P3), washing (P4), chilling (P5) and the packaged end-product (P6). In the first set of carcasses, the Salmonella incidence determined by the conventional method was 38.3% and 22.5% by SS/SV(TM). In the set for evaluation of OSRT(TM), the number of positive samples was the same detected by the cultural procedure (49.0%). In the third set, the positivity by the conventional procedure was 33.3%, and 5.0% by REVEAL(TM). The comparisons of positives in the first and third sets of carcasses were significantly different (P < 0.05). The positivity for Salmonella, in carcasses at P1 to P6, as determined by at least one of the methods, was 47.5%, 47.5%, 32.5%, 30.0%, 30.0% and 37.7%, respectively