RESUMOAvaliaram-se o pH e a qualidade microbiológica de ovos integrais pasteurizados refrigerados obtidos de dois tipos de matéria-prima: o ovo in natura (comercial ) e o ovo galado (ovo fértil). Os tratamentos foram dispostos no delineamento inteiramente ao acaso, em parcelas subdivididas, sendo na parcela dois tipos de ovos integrais pasteurizados, o comercial e o galado, e na subparcela quatro períodos de estocagem sob temperatura de refrigeração, um, sete, 14 e 21 dias. Não foi observada a presença de Salmonella spp. em nenhuma amostra analisada, e para os ovos comerciais, o período de estocagem não contribuiu para o aumento (P>0,05) da contaminação por mesófilos aeróbios, coliformes a 35ºC, Staphylococcus spp. e bolores e leveduras. Para as amostras de ovos galados, o período de armazenamento influenciou no aumento (P<0,05) da contagem de mesófilos aeróbios, coliformes a 35ºC, bolores e leveduras, e Staphylococcus spp. Os valores de pH aumentaram durante os primeiros dias do armazenamento e depois voltaram a diminuir. Concluiu-se que os ovos integrais galados pasteurizados apresentam pior qualidade em relação aos ovos integrais comerciais pasteurizados, e que o período de validade sob refrigeração desses tipos de ovos poderia ser de sete e 14 dias, respectivamente.Palavras-chave: ovo integral pasteurizado refrigerado, ovo galado, armazenamento, microbiologia, pH ABSTRACTThe pH and microbiological quality of refrigerated pasteurized whole eggs at 4ºC obtained from two types of raw materials, in nature (commercial) egg and the fertile egg were evaluated. The treatments were arranged in a completely randomized split plot design, the two types of pasteurized whole eggs (commercial and fertile) were alloted to the plots and four periods of storage under refrigeration (one, seven, 14 and 21 days)

A quantitative and confirmatory high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method for the determination of bioactive amines in the albumen and yolk of commercial eggs was developed, optimized and validated by analyte extraction with trichloroacetic acid and pre-column derivatization with dansyl chloride. Phenylethylamine, putrescine, cadaverine, histamine, tyramine, spermidine and spermine standards were used to evaluate the following performance parameters: limit of detection (LoD), limit of quantification (LoQ), selectivity, linearity, precision, recovery and ruggedness. The LoD of the method was defined from 0.2 to 0.3 mg kg(-1) for the yolk matrix and from 0.2 to 0.4 mg kg(-1) for the albumen matrix; the LoQ was from 0.7 to 1.0 mg kg(-1) for the yolk matrix and from 0.7 to 1.1 mg kg(-1) for the albumen matrix. The validated method exhibited excellent selectivity and separation of all amines with coefficients of determination higher than 0.99. The obtained recovery values were from 90.5% to 108.3%, and the relative standard deviation (RSD) was lower than 10% under repeatability conditions for the studied analytes. The performance parameters show the validated method to be adequate for the determination of bioactive amines in egg albumen and yolk.

This study was carried out with the aim of evaluating the effects of mineral oil application on eggshells and the use of plastic packages with lids on the physical-chemical and microbiological quality and biogenic amine contents of eggs stored under refrigeration for up to 125 d. A total of 1,920 eggs from 46-wk-old Hyline W36 laying hens were randomly distributed into 4 groups soon after classification: (i) 480 eggs were stored in pulp carton tray packages; (ii) 480 eggs were stored in plastic packages with lids; (iii) 480 eggs were stored in carton packages after the application of mineral oil; and (iv) 480 eggs were stored in plastic packages with lids after the application of mineral oil. The internal quality was measured by Haugh units, by the counts of mesophilic and psychrotrophic microorganisms, by the most probable number of total and thermal-tolerant coliforms, by the counts of molds and yeasts, by the analysis of Salmonella spp. and Staphylococcus spp., and by the levels of biogenic amines in the egg yolk and albumen. The application of mineral oil to the eggshell resulted in higher Haugh unit values throughout storage, and the use of plastic packages altered the internal quality. The application of mineral oil and the use of packaging had no effects on the microbiological and biogenic amine results. Microbiological analyses showed the absence of Salmonella spp., Staphylococcus aureus, thermal-tolerant coliforms, and fungi. However, the highest counts of mesophilic (1.1 × 10(7) cfu/g) and psychrotrophic (6.7 × 10(7) cfu/g) microorganisms were recorded. The highest values of biogenic amines detected and quantified were putrescine (2.38 mg/kg) and cadaverine (7.27 mg/kg) in the egg yolk and putrescine (1.95 mg/kg), cadaverine (2.83 mg/kg), and phenylethylamine (2.57 mg/kg) in the albumen. Despite these results, the biogenic amine levels recorded were considered low and would not be harmful to consumer health.

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The objective of this study was to evaluate the correlation between the levels of bioactive amines and the microbiological quality of liquid pasteurized egg stored under refrigeration. Pasteurized whole egg liquid was obtained from 2 types of different raw materials, fresh eggs, and commercial fertile eggs. They were stored under refrigeration over a period of 21 d. The treatments were arranged in a completely randomized split plot, with the plots being the 2 types of liquid pasteurized egg, and the subplots being the 4 storage periods (1, 7, 14, and 21 d). The storage period did not contribute to the increase (P > 0.05) of contamination by mesophilic aerobic microorganisms and total coliforms in commercial liquid pasteurized egg. However, for fertile eggs, the storage period led to an increase (P < 0.05) in the numbers of microorganisms. Levels of the amines putrescine, cadaverine, and tyramine were detected only in fertile liquid pasteurized egg, and the storage period contributed to the increase (P < 0.05) in the levels of these amines. There was a high correlation between total coliform most probable number and cadaverine levels, and a moderate correlation between the numbers of aerobic mesophilic microorganisms and tyramine levels. It was concluded that the most contaminated liquid pasteurized eggs were the fertile liquid pasteurized eggs and this caused the highest levels of bioactive amines in them compared with all the eggs that had been subjected to pasteurization and refrigerated storage.

In order to evaluate the efficiency of the pasteurization process in liquid whole eggs, an UV/visible spectrophotometric method was developed and validated for the assessment of alpha-amylase activity. Samples were collected from 30 lots of raw eggs (n = 30) and divided into three groups: one was reserved for analysis of the raw eggs, the second group was pasteurized at 61.1°C for 3.5 minutes (n = 30), and the third group was pasteurized at 64.4°C for 2.5 minutes (n = 30). In addition to assessing alpha-amylase activity, the microbiological quality of the samples was also evaluated by counting total and thermotolerant coliforms, mesophilic aerobic microorganisms, Staphylococcus spp., and Salmonella spp. The validated spectrophotometric method demonstrated linearity, with a coefficient of determination (R2) greater than 0.99, limits of detection (LOD) and quantification (LOQ) of 0.48 mg kg-1 and 1.16 mg kg-1, respectively, and acceptable precision and accuracy with relative standard deviation (RSD) values of less than 10% and recovery rates between 98.81% and 105.40%. The results for alpha-amylase activity in the raw egg samples showed high enzyme activity due to near-complete hydrolysis of the starch, while in the eggs pasteurized at 61.1°C, partial inactivation of the enzyme was observed. In the samples of whole eggs pasteurized at 64.4°C, starch hydrolysis did not occur due to enzyme inactivation. The results of the microbiological analyses showed a decrease (P < 0.0001) in the counts for all the studied microorganisms and in the frequency of Salmonella spp. in the pasteurized egg samples according to the two binomials under investigation, compared to the raw egg samples, which showed high rates of contamination (P < 0.0001). After pasteurization, only one sample (3.33%) was positive for Salmonella spp., indicating failure in the pasteurization process, which was confirmed by the alpha-amylase test. It was concluded that the validated methodology for testing alpha-amylase activity is adequate for assessing the efficiency of the pasteurization process, and that the time-temperature binomial used in this study is suitable to produce pasteurized eggs with high microbiological quality.

A indústria queijeira representa um importante segmento do setor lácteo. Minas Gerais é o maior produtor de queijo do Brasil, produzindo 215 mil toneladas por ano, o que equivale a 50% da produção nacional (Martins, 2001). Em Minas Gerais, os mais produzidos são, em ordem, o queijo mozarela, o queijo-de-minas (Minas padrão e Minas frescal) e o requeijão, correspondendo, respectivamente, a 24%, 21% e 14,5% do total da produção. A maior parte dos laticínios do estado está concentrada nas regiões Sul de Minas (36,5%), Zona da Mata (17%), Triângulo Mineiro e Alto Paranaíba (14,8%) e Zona Metalúrgica (14,4%) (Martins, 2001). O soro lácteo pode ser definido como a fração aquosa do leite que é separada da caseína durante a produção de queijos, correspondendo a cerca de 90% do volume do leite, levando consigo 50 a 55% dos sólidos totais do mesmo (Kosikowski, 1979; Furtado e Lourenço Neto, 1994).A utilização do soro na indústria alimentícia vem sendo estudada por diversos autores, e cada vez mais tem-se utilizado essa matéria-prima na elaboração de novos produtos, seja como simples substituto da água ou como ingrediente de funcionalidade reológica ou nutricional. Esses novos produtos passaram, então, a fazer parte da dieta da população, incluindo os idosos e principalmente as crianças, o que faz com que o controle da qualidade, não só nutricional, mas também higiênico-sanitário do soro, seja fundamental (Chiappini et al., 1995a,b).Poucos são os trabalhos que avaliaram a microbiota do soro. Quanto à qualidade microbiológica, o soro pode ser um produto de curta vida útil devido ao elevado valor nutritivo, às condições de umidade e ao pH, que são favoráveis ao crescimento microbiano. Alguns trabalhos demonstraram que é preocupante a contaminação por coliformes (Chiappini et al., 1995a).Não existem na legislação brasileira atual padrões para sua inspeção físico-química ou microbiológica. Dentre os produtos que aguardam a criação dos padrões de identidade e qualidade estão o Minas padrão e a ricota, que são produtos de origem e destino do soro de queijo, respectivamente (Teixeira, 2005). Para se fazer uma avaliação da qualidade microbiológica do soro de queijos produzidos em Minas Gerais, foram coletadas 24 amostras de soro de cada tipo de queijo (Minas padrão e mozarela) em quatro macrorregiões de Minas Gerais, em laticínios de médio e grande porte, sob inspeção federal. As amostras foram coletadas diretamente do tanque de produção, logo após o corte da massa, em recipiente plástico esterilizado acondicionado com gelo reciclável e transportado em caixas isotérmicas.

The temperature control in the processing room is one of the major factors associated with the production of safe food with a satisfactory microbiological quality. A total of 288 samples of skinless chicken breast meat were placed in a cutting room, subjected to four different temperatures (12ºC, 14ºC, 16ºC and 18ºC) and collected to evaluate the influence of the room temperature on the microbiological quality during the cutting and boning of chicken breasts. Aerobic mesophilic microorganisms were counted to evaluate the environmental contamination. In addition, coliforms at 35ºC and 45ºC and Staphylococcus spp. were counted, and an analysis for the presence of staphylococcal enterotoxins and Salmonella spp. was performed to determine the microbiological quality of the meat. The results showed an increase in environmental contamination (P=0.01) with an increase in room temperature. However, no significant differences (P˃0.05) were observed in the meat cuts regarding the counts of coliforms at 35ºC and 45ºC, the count of Staphylococcus spp. and the presence of Salmonella spp. Moreover, no staphylococcal enterotoxins were detected in the samples analyzed. Thus, despite increasing the environmental contamination, the increase in the cutting room temperature did not affect the microbiological quality of the final product.Keywords: Microbiological quality, environmental contamination, chicken breast meat, cutting room temperature RESUMO