The present research aimed to optimize the process of osmotic dehydration (OD) of ginger with hypertonic sucrose solution employing response surface methodology. A 23 experimental planning was carried out and 17 experimental assays were performed based on three independent variables (temperature, concentration of the osmotic solution and immersion time) and three dependent variables (moisture loss (ML), solids gain (SG) and dehydration efficiency index (DEI)). The selected assay conditions exhibited the preferred DEI value (the highest ML and lower SG), which were considered in the optimization. Assay 16 demonstrated to be the most favorable conditions for the osmotic dehydration of ginger (DEI =1.61) at 40 40 °C, 50 °Brix and 90 minutes of immersion time. Assay 1 performed at 34 °C, 44 °Brix and 120 minutes of immersion time also displayed desirable response (DEI =1.45). Thus, these two assays were evaluated for the presence of thermal-tolerant coliforms: Bacillus cereus and Salmonella sp.. The analyses presented values below the acceptable limits, which assured high quality hygienic and sanitary conditions of the product.

-With the present study aimed to evaluate the antagonistic action of Lactobacillus acidophilus front of Escherichia coli, Staphylococcus aureus and Listeria monocytogenes. In vitro tests were performed using Petri dishes with MRS agar and the milk fermented with Lactobacillus acidophilus also analyzed the chemistry and physical characteristics of the product during 35 days of storage under refrigeration. It has been observed in vitro formation of inhibition zones, ranging from 6 to 18 mm diameter, compared to the tested pathogens by lactic culture raises, indicating the possibility of producing organic acids, bacteriocins or other growth-inhibiting substances. In the fermented milk prepared, during storage, the probiotic microorganism tested was able to inhibit the growth of E. coli O157: H7 and L. monocytogenes; and the log cycle reduction of S. aureus.

The objective of this study was to assess the technical and economic feasibility of the use of whey resulting from the cheese making process in the State of Rio de Janeiro. Data was collected from 52 dairy plants that produce or buy whey, by means of questionnaires. Based on the data obtained, a mathematical model for the location of processing plants was built, considering production logistics, sample collection, regions with potential to locate whey processing plants and possible areas of environmental impact from cheese industries. Whey processing was more concentrated in the south of the state of Rio de Janeiro, with 59.5% during the season, and 58.4% in the off-season period. The production in the season and off-season periods was stable, with good distribution throughout the State. Only 30.7% of the total whey generated was used by industries to produce dairy beverages and ricotta, and 70.3% was discarded. According to the present study, the ideal solution for the use of whey in the referred region, should consider the establishment of two processing plants and the definition of strategic convergence points (whey drying facilities, in Macuco and Valença), and the subsequent transport of the products for final processing.

ResumoO objetivo do trabalho foi avaliar a qualidade do soro por meio da contagem de micro-organismos mesófilos, psicrotróficos e enumeração de coliformes e da detecção de bacteriófagos e antimicrobianos. Para verificar a qualidade e o uso do soro juntamente com a coleta, foi aplicado um questionário em 50 estabelecimentos processadores de leite e derivados fiscalizados no Estado do Rio de Janeiro. De todo soro produzido (4.114 toneladas) 30,76% é aproveitado na produção de derivados lácteos, 29,18% é enviado para Minas Gerais, 7,18% vendido, 32,88% distribuído para alimentação animal. Somente nove estabelecimentos realizam programa de controle de qualidade. A avaliação bacteriológica apresentou 86,36% de bactérias psicrotróficas acima do valor permitido por lei, 36% amostras positivas para antimicrobianos e negatividade para bacteriófagos. Na colimetria os coliformes a 35 o C apresentou em 60% das amostras valor médio de 2,8 x10 4 NMP / mL, os coliformes a 45°C com valor médio de 2,5 x10 4 NMP / mL e encontrado Escherichia coli em 30% das amostras. A ausência de fago é um ponto positivo para as indústrias, assim como o aproveitamento parcial do soro. A presença de antimicrobianos é considerada um risco saúde do consumidor.Palavras-chave: soro de queijo, qualidade microbiológica, antibiótico, fagos. AbstractThe objective of this study was to evaluate cheese whey quality regards to mesophilic, psychrotrophic and coliforms bacteria, bacteriophages and antimicrobial substances detection. The samples were collected from 50 dairy industries in Rio de Janeiro state and a questionnaire was carried out. Of total whey produced, 30.7% were utilized to dairy products production, and 42.15% were concentrated and sent to Minas Gerais state, 10.37% were sold and 47.48% distributed to animal feed. Bacteriological evaluation showed high count of psychrotrophic bacteria (86.36%). Seventeen samples (36%) were positive to antimicrobial analysis. The search of bacteriophages was negative to all samples. Relative to 35 o C colimetric counts, 40% of samples presented more than 1.1 x10 4 NMP/mL and 60% of samples presented 2.8 x10 4 NMP/mL. The coliforms 45° C counts were 2.5 x10 4 NMP/mL and it was found Escherichia coli in 30% of samples. The absence of phage was a positive point to industries as well as the rational use of whey, however the presence of antimicrobial agents could be considered a risk to the consumer.Keywords: cheese whey, microbiological quality, antibiotics, phages IntroduçãoO soro de leite é o líquido formado a partir da coagulação das caseínas do leite, considerado um subproduto, correspondendo cerca de 90% do volume inicial do leite, perfazendo de 50 a 55% dos sólidos totais do mesmo (Furtado e Lourenço Neto, 1994;Antunes, 2003). Nas indústrias, este produto apresenta valor comercial baixo quando in natura e apresenta alto custo de captação, normalmente tratado como dejeto e lançado nos cursos dos rios sem tratamento prévio, sendo um poluente ambiental aumentando a demanda bioquímica de oxigênio (Chehadi, 2004;B...

As amostras I1 e I2 foram classificadas como tradicional e integral, a amostra I3 parcialmente desnatada e "light" e I4 desnatada e "diet". Concluímos a elaboração das quatro amostras dentro dos padrões físico-químicos e a classificação das mesmas em produtos "light" e "diet". * Legislação IN 46 (BRASIL,2007) ** Resultados expostos em g de ácido lático/100 g de iogurte Letras sobrescritos iguais não diferem significativamente (p>0,05) pelo teste de Duncan