RESUMO: Foram avaliadas a ação de celulases e pectinases comerciais e não comerciais na hidrólise de casca de soja (CS) e palha e espigas de milho (PEM), o efeito da temperatura e da agitação na hidrólise do substrato lignocelulósico e as características bromatológicas dos substratos hidrolisados. O efeito do pré-tratamento na hidrólise de resíduos lignocelulósicos e a análise bromatológica também foram avaliados. A maior atividade hidrolítica ocorreu a 300 rpm para CS (47,95 e 51,43% para celulase e pectinase, respectivamente) e a 350 rpm para PEM (26,05 e 9,23% para celulase e pectinase, respectivamente). As enzimas não comerciais atingiram 7,26-30% da quantidade de hidrólise obtida com as enzimas comerciais, nos mesmos substratos. O pré-tratamento com 7,5% de NaOH e um tamanho de partícula do substrato de 0,5 mm aumentou significativamente a hidrólise de CS e PEM para ambas as enzimas. As características bromatológicas mostraram que a casca de soja hidrolisada com celulase e pectinase comercial tem potencial para uso em larga escala na produção de ração animal.

ABSTRACT: This study evaluated the action of commercial and non-commercial cellulases and pectinases in the hydrolysis of soybean hulls (SH) and corn stover and cobs (CSC), the effect of temperature and agitation on the lignocellulosic substrate hydrolysis and the bromatological characteristics of hydrolyzed substrates. The effect of pretreatment on the hydrolysis of lignocellulosic residues and bromatological analysis were also evaluated. The highest hydrolytic activity occurred at 300 rpm for SH (47.95 and 51.43% for cellulase and pectinase, respectively) and at 350 rpm for CSC (26.05 and 9.23% for cellulase and pectinase, respectively). Non-commercial enzymes achieved 7.26-30% of the amount of hydrolysis obtained with commercial enzymes, on the same substrates. Pretreatment with 7.5% of NaOH and a particle size of the substrate of 0.5 mm significantly increased the hydrolysis of SH and CSC for both enzymes. The bromatological characteristics showed that soybean hulls hydrolyzed with both commercial cellulase and pectinase have potential for large-scale use in animal feed production.

Abstract Given possible temperature variations in the cold chain during retail display of chilled food, this work evaluated the growth of Salmonella choleraesuis and Staphylococcus aureus inoculated in chicken breast fillet submitted to different temperature abuses. The bacterial growth was evaluated in Luria–Bertani broth and previously inoculated chicken breast fillet cooled for 12h and incubated at different temperatures (5, 20, and 25 °C) for 12 h and 5 ºC for 12 days. The maximum growth rate and maximum growth were determined. The microorganisms grew at all studied temperatures, with a significantly lower growth at 5 °C compared with 20 and 25 °C. S. choleraesuis showed higher growth than S. aureus in both culture medium and chicken breast, and major maximum growth in culture medium than chicken breast, at all studied temperatures. Salmonella sp. and S. aureus were not detected in the control treatment maintained at 5 °C, and the thermotolerant bacteria remained within the standards allowed by Brazilian legislation when stored for 12 days. However, temperature abuse resulted in the vulnerability and spoilage of chicken breast fillet quality. The effects of temperature abuse caused by negligence on the microbial growth (Ymax) and growth rate (µmax) in chicken breast fillet, under industrial conditions was demonstrated.

Abstract To keep up with chicken meat demand, genetic improvement, field performance, and technological processes have been sought. However, some consequences of this are already being observed, such as constant divergences in physicochemical parameters of in nature chicken cuts, since legislation has not been revised at the same speed. Thus, this work aimed to evaluate water content, protein and water content/protein ratio (W/P) for different conditions (slaughter, lineage, sex, and processing) and compliance with current legislation (Brazilian and European). Breast and half breast, drumstick and thigh cuts of in nature chicken were assessed. A significant difference was found in sex, with lower values in the females. Chickens have water content levels higher than those required by Brazilian legislation. In the different cuts evaluated, discrepancies were observed in relation to legislation. There was no compliance with W/P ratio to European legislation, where incompatibility approached 26.67% for skinless breast, 6.67% for breast and half chest and 64.44% for thigh and drumstick. The results reinforce the need for continuity of studies that support the revision of current legislation, clarifications regarding the calculations used to determine the established standards and clarifications of the collection and analysis methodologies currently employed.

Abstract (1) Background: The aim of this study was to evaluate the production and partial characterization of xylanase and avicelase by a newly isolated Penicillium sp. in solid-state fermentation, using soybean hulls as substrate. (2) Methods: Temperature, time, number of spores, and substrate moisture on xylanase and avicelase bioproduction were evaluated, maximizing activity with 30°C, 1x106 spores/g substrate, 14 and 7 days of fermentation with 70 and 76% substrate moisture contents, for xylanase and avicelase, respectively. (3) Results: Different solvents, temperatures, and agitation in the enzymatic extraction were evaluated, obtaining higher activities, 430.77 and 26.77 U/g for xylanase and avicelase using 30 min extraction and 0.05 M citrate buffer solution (pH 4.5 ), respectively at 60°C and 175 rpm and 50°C and 125 rpm. The optimum pH and temperature for enzymatic activity determination were 5.3 and 50°C. Enzyme extract stability was evaluated, obtaining higher stability with pH between 4.5 and 5.5, higher temperature of up to 40°C. The kinetic thermal denaturation (Kd), half-life time, D-value, and Z-value were similar for both enzymes. The xylanase Ed value (89.1 kJ/mol) was slightly lower than the avicelase one (96.7 kJ/mol), indicating higher thermostability for avicelase. (4) Conclusion: In this way, the production of cellulases using alternative substrates is a way to reduce production costs, since they represent about 10% of the world demand of enzymes, with application in animal feed processing, food production and breweries, textile processing, detergent and laundry production, pulp manufacturing and the production of biofuels.

Abstract Cooling of carcasses using water immersion is the most used process in the poultry industry. In this stage, besides the reduction of temperature, water absorption in the carcasses occurs and, consequently, in the chicken cuts, which are monitored by the companies and supervised by the Ministry of Agriculture, Livestock, and Supply of Brazil, which establishes water absorption limits. The objective of this work was to evaluate the process capacity analysis tool to analyze the water absorption capacity by chicken carcasses during precooling, based on the absorption indexes obtained on an industrial scale, by the analysis of 720 carcasses. After structural alterations, aiming at greater bubble control and shorter residence time of the chicken carcasses in the cooling system, Cp (process potential index) and Cpk (process performance index) were close to each other (0.82 and 0.81, respectively), indicating that the process is practically centralized and, although it has become smaller than 1, presented a significant improvement over the initial evaluation (cp 0.35 and cpk 0.26).

Abstract The sensory, physical-chemical and microbiological characteristics of boneless chicken thighs and drumsticks stored at different temperatures were evaluated. Samples stored at −6 and −12 °C, in natura and cooked, presented changes in sensory characteristics from the sixth and fifth month of storage, respectively. In natura samples kept at −18 °C presented sensory modification from the eighth month, and cooked samples did not show alterations during 12 months of storage. For lipid oxidation, differences were observed between −6 and −12 °C by the third month and between −12 and −18 °C after 12 months of storage. Related to protein oxidation, samples stored at −18 °C did not differ from the standard (0 days), showing values of 6.03 nmol carbonyl/mg protein after 12 months of storage. Samples under freezing at −6 °C for 12 months presented an increase in psychrotrophic count. This behaviour was not observed in the samples stored at −12 and −18 °C. Considering the different analyzes, the maximum storage period was 6 days at 4 °C, 8 months at –6 and –12 °C and at least 12 months storage at –18 °C.

Resumo O Salame Tipo Italiano produzido no Brasil é predominantemente obtido de carne suína, com maturação aproximada de 30 dias, atingindo pH em torno de 5,4. O uso das bactérias do gênero Lactobacillus como culturas iniciadoras propicia o processo de fermentação e a obtenção de produtos uniformes e seguros, com redução do tempo de maturação devido à rápida formação de ácido lático, obtendo-se melhores características sensoriais, químicas e microbiológicas. Os estafilococos coagulase-negativos (comumente em produtos cárneos fermentados Staphylococcus xylosus e S. carnosus)possuem vantagens tecnológicas, como atividade de nitrito e nitrato redutase, consumo de oxigênio e atividade de catalase que melhoram a estabilidade de cor e diminuem o desenvolvimento de rancidez no produto, além de contribuírem para a geração de sabor devido à capacidade proteolítica e lipolítica. Portanto, este trabalho objetivou estudar a influência de diferentes culturas starters (S. xylosus, S. carnosus, L. sakei e L. plantarum)combinadascom diferentes concentrações de substrato de glicose (40,5 e 99,5%) na fabricação do Salame Tipo Italiano, bem como a influência da concentração destes no desempenho das culturas starters. Durante o processamento e shelf life, os salames foram avaliados quanto às características físico-químicas, microbiológicas e sensoriais. Em todas as amostras de Salame Tipo Italiano houve comportamento similar em relação aos parâmetros físico-químicos (umidade, proteína e gordura). Não houve crescimento de micro-organismos indesejáveis nas amostras analisadas após 60 dias de shelf life. Na análise sensorial, a amostra com menor concentração de substrato (40,5%), utilizando as culturas S. carnosus e L. sakei, foi a que recebeu as melhores notas e melhor aceitação pelos degustadores, além de apresentar valores de nitritos e nitratos de acordo com a legislação.

Abstract The Italian-Type Sausage produced in Brazil is predominantly obtained from swine meat, with maturation approximately 30 days, reaching pH around 5.3. The use of Lactobacillus bacteria as starter cultures provide fermentation processes and products more uniform and safe, reducing the maturation time due to the rapid formation of lactic acid, obtaining products with better sensorial, chemical and microbiological characteristics. Coagulase-negative staphylococci (commonly in S. xylosus and S. carnosus fermented meat products) have technological advantages such as nitrite and nitrate redutase activity, oxygen uptake and catalase activity that improve color stability and decrease the development of rancidity in the skin, contribute to the generation of flavor due to the proteolytic and lipolytic capacity. This work aimed to study the influence of different starters cultures (S. xylosus, S. carnosus, L. sakei and L. plantarum) combined with different concentrations of glucose substrate (40.5 and 99.5%) in properties of Italian-Type Sausage, as well as the influence of their concentration on starter performance. During the processing and shelf life the sausages were evaluated in relation to physic-chemical, microbiological and sensorial characteristics. In all samples of Italian-type Sausages have similar behavior in relation to physical-chemical parameters (moisture, protein, and fat). There was no growth of undesirable micro-organisms in the samples after 60 days of shelf life. By the sensorial analysis, the sample with low concentration of substrate (40.5%) and with S. carnosus and L. sakei cultures was the one that received the best grades and better acceptance by the tasters, and presented values of nitrites and nitrites according to the legislation.

ABSTRACT. The aim of this study was to evaluate the action of commercial and non-commercial cellulase and pectinase on rice husk and Tifton 85 hay hydrolyses. The hydrolysis kinetics of the substrates with commercial cellulase and pectinase were evaluated and the hydrolysis at different temperature and agitation conditions was maximized using experimental design. The combined use of commercial and non-commercial enzymes under optimized conditions was evaluated. The pre-treatment of the residues was also investigated by milling and different concentrations of NaOH. Finally, the effect of the hydrolysis on the bromatological composition of the residues was evaluated. The best hydrolysis times of rice husk and Tifton 85 hay were 10 and 12h for commercial cellulase, 12 and 14h for non-commercial cellulase, 10 and 14h for commercial pectinase and 16 and 20h for non-commercial pectinase, respectively. The highest hydrolysis values were obtained using commercial cellulase with 1:50 (w:v enzyme:water) dilution rate, at 45ºC and 300 rpm agitation for both substrates, reaching 20.6% maximum percentage for Tifton 85 hay and 11.6% for rice husk. The combined use of commercial enzymes did not increase hydrolysis percentage. The pre-treatment using 7.5% NaOH and 0.5 mm grain size significantly increased the rice husk and Tifton 85 hay hydrolyses (60-80%), either using commercial cellulase or pectinase enzymes. The use of non-commercial enzymes provided 18-30% hydrolysis obtained from commercial ones. Bromatological analyzes indicated a reduction in neutral detergent fiber and acid detergent fiber content for rice husk and Tifton 85 hay when using pectinases and commercial cellulases.

ABSTRACT Among the nutrients involved in the chicken diet, the microminerals deserve attention as they exert essential functions in the organism. These compounds can be provided in inorganic (traditional) and organic (chelate) forms. In organic form, the micromimerals can attend a new concept related to a better bio-availability. In this sense, the objective of this work was to evaluate the effect of the partial and total substitution of inorganic by organic sources of microminerals on the animal diet, assessing its concentration in the blood and liver after 21 and 40 days and also in the bones after 40 days. Moreover, the effect on the physical-chemical and sensory characteristics of the muscle after 15 days of storage at 4°C was also evaluated. The animals were divided into five treatments: 100% inorganic, 70% inorganic and 30% organic, 50% inorganic and 50% organic, 30% inorganic and 70% organic and 100% organic-chelate. It is shown that the use of organic sources of microminerals in the diet of poultry induced to an increase of its concentrations in the blood and liver, with no significant alterations in the compositions of bones, compared to the use of inorganic sources. Feed formulated using 50% of organic minerals and 50% of inorganic minerals led to similar results. The diet with organic minerals or mixture with inorganic sources results in a low lipid oxidation in the drumsticks stored at 4°C for 15 days, in comparison with those using only inorganic minerals. No sensory alterations were observed for all different treatments.

Abstract Considering the microbial safety of consumption of raw foods (Asian food), this study aimed to explore the inactivation S. aureus in raw salmon by supercritical CO2 treatment (SC-CO2). For this purpose, experimental design methodology was employed as a tool to evaluate the effects of pressure (120-220 bar), the depressurization rate (10 to 100 bar.min–1) and the salmon:CO2 mass relation (1:0.2 to 1:1.0). It was observed that the pressure and the depressurization rate was statistically significant, i.e. the higher the system pressure and depressurization rate, the greater the microbial inactivation. The salmon: CO2 mass relation did not influence the S. aureus inactivation in raw salmon. There was a total reduction in S. aureus with 225 bar, a depressurizing rate of 100 bar.min–1, a salmon: CO2 mass relation of 1:0.6, for 2 hours at 33 °C.

This study aimed to compare the chemical composition and in vitro antibacterial and antioxidant activity of commercial essential oils of rosemary, clove, oregano, sage and binary combination of clove and oregano. Eugenol (89.58%) for clove, carvacrol (60.71%) for oregano, bornyl acetate (39.64%) for rosemary, linalool (39.26%) for sage and eugenol (56.42%) for binary combination were identified as the main components . In evaluation of antibacterial activity, the oregano showed the highest inhibition zones and the smallest minimum inhibitory concentration. The binary combination with IC50 of 6.40 μg/mL, followed by clove with IC50 of 11.79 μg/mL had excellent antioxidant potential.

Este estudio tuvo como objetivos comparar la composicion quimica y actividad antioxidante y antibacteriana in vitro de los aceites esenciales comerciales de romero, clavo de olor, oregano, salvia y combinacion binaria de clavo y oregano. Fueron identificados como componentes principales, eugenol (89,58%) para el clavo, el carvacrol (60,71%) para el oregano, el acetato de bornilo (39,64%) de romero, linalol (39,26%) de la salvia y el eugenol (56,42%) para la combinacion binaria. En la evaluacion de la actividad antibacteriana el oregano mostro las zonas de inhibicion mas altas y la concentracion inhibitoria minima mas pequena. La combinacion binaria con IC50 de 6,40 μg/mL, seguido de clavo de olor con IC50 de 11,79 μg/mL tiene un excelente potencial antioxidante.

Com a intenção de minimizar a carência de produtos isentos de glúten e tendo em vista o crescente aumento de celíacos, a elaboração de produtos diferenciais a base de farinha de arroz e milho torna-se uma alternativa de consumo e comercialização. Assim, este trabalho teve como objetivo avaliar os efeitos da adição de farinha de arroz e milho, e emulsificante nas características de qualidade (teste de cozimento, textura instrumental - firmeza e aceitabilidade) e físico-químicas (proteínas, lipídios, carboidratos, minerais e fibra alimentar) de formulações de macarrão, mediante o emprego de metodologia de planejamento de experimentos, fixando a concentração de ovos in natura (12%, m/m) e água (20%, v/m). A formulação com 40g de farinha de milho, 60g de farinha de arroz e 0,4g de SSL por 100g de farinha mista foi a que apresentou melhor resistência ao cozimento, menores perdas de sólidos na água de cocção (2,12% m/m), textura (30,40g seg-1) e aceitabilidade superior a 85 %. Além disso, o uso de farinha de arroz, associado à farinha de milho, proporciona fonte de minerais (152mg de K, 1,55mg de Fe, 46mg de Mg, 20mg de Ca por 100g), proteínas (~7%), carboidratos (52%) e fibras (~1%), importante suprimento nutricional para celíacos, por estes apresentarem perdas significativas destes nutrientes, devido à diarreia e à absorção restrita, característica da doença.

In order to minimize the deficiency of products with gluten-free and the growing number of celiac the elaboration of differential products using rice and maize flour becomes an alternative of consuming and marketing. This study aimed to evaluate the effects of rice and maize flour, and emulsifier addition in the quality characteristics (cooking test, instrumental texture - firmness and acceptability) and physic-chemical (proteins, lipids, carbohydrates, minerals and dietary fiber) of pasta formulation, by the use of experimental design methodology, fixing the concentration of in nature eggs (12%, w/w) and water (20%, v/w). The formulation with 40g of maize flour, 60g of rice flour and 0.4g per 100g of SSL mixed flour showed the better cooking resistance, reduced loss of solids in the cooking water (2.12% m/m), texture (30.40g sec-1) and acceptability higher than 85%. Furthermore, the use of rice flour associated with maize flour provide a source of minerals (152mg of K, 1.55mg of Fe, 46mg of Mg, 20mg Ca per 100g), proteins (~ 7%), carbohydrates (52%), fibers (~1%) important nutritional supplement for celiac, because they present significant losses of these nutrients due to restricted absortion and diarrhea, characteristic of the disease.

The objective of this work was to evaluate the effect of different water pressures and concentrations of lactic acid on microbial counts (mesophilic bacteria, enterobacteria and Salmonella) on pig carcasses without contamination and contaminated carcasses, before and after the last shower and before being cooled. The tests were carried out using 4, 3 and 2 bar water pressure, and 2, 1 and 0% lactic acid concentration. In general, both the pressure in the shower and lactic acid had a positive effect by reducing the microbial count. The interaction between the pressure and lactic acid caused the largest reduction in carcasses surface count for mesophiles. With regard to enterobacteria on contaminated carcasses, the most important variable was the lactic acid concentration and in uncontaminated carcasses, it was water pressure. The use of 8 bar pressure of the wash water without lactic acid caused a reduction in mesophilic bacteria and enterobacteria, for both the contaminated and uncontaminated carcasses, with results statistically equal to each other, and significantly lower than the initial counts. The water pressure at 8 bar reduced the percentage of carcasses with Salmonella in contaminated carcasses.

Penicillium brasilianum was previously isolated from tea and identified by molecular biology technique. A Plackett-Burman design, followed by a complete second order design was used for the screening of most important factors and to maximize the pectin liase (PMGL) activity, respectively. The maximum PMGL activity by P. brasilianum achieved was 9.0 U/mL after 48 h of cultivation in a medium containing pectin (33.0 g/L), yeast extract (30.0 g/L) and potassium phosphate (2.0 g/L) at 30ºC, with a stirring rate of 180 rpm, initial pH 5.5 and 5x106spores/mL inoculum size. The kinetic evaluation in terms of substrate consumption demonstrated that the maximum production of PMGL was at 72 h, and 40% of the total organic carbon, 25% of the nitrogen, 88% of the magnesium, 13% of the potassium and 66% of the iron were consumed. The pH remained almost stable during the whole period of production (5.33 to 4.9). The partial characterization of the crude PMGL enzyme extract showed optimal pH and temperature of 5.5 and 37°C, respectively.

Biofilms in milk cooling tanks compromise product quality even on farms. Due to the lack of studies of this topic, this study evaluated the microbiological conditions of raw milk cooling tanks on farms and characterized the microorganisms isolated from these tanks. Samples were wiped off with sterile swabs from seven milk cooling tanks in three different points in each tank. Mesophiles and psychrotrophic counts were performed in all samples. The isolation of Pseudomonas spp., Bacillus cereus and atypical colonies formed on selective media were also performed, totalizing 297 isolates. All isolates were tested for protease and lipase production and biofilm formation. Of the total isolates, 62.9% produced protease, 55.9% produced lipase, and 50.2% produced biofilm. The most widespread genus inside the milk cooling tank was Pseudomonas since it was not possible to associate this contamination with a single sampling point in the equipment. High counts of microorganisms were found in some cooling tanks, indicating poor cleaning of the equipment and providing strong evidences of microbial biofilm presence. Moreover, it is worth mentioning the milk potential contamination with both microbial cells and their degrading enzymes, which compromises milk quality.