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 The ultrasound effect on functional and structural properties of hydrolysates of different bovine collagens (fibers, gelatines and hydrolysates) was evaluated. The enzymatically hydrolyzed samples (enzyme Alcalase®) with previous or simultaneous ultrasound treatment presented higher number of bands with shorter wavelengths (mid-FTIR). The ultrasound provided the samples with a higher hydrolysis degree and favored the antimicrobial activity, evidencing the advantages of its use in the process. Results revealed that higher hydrolysis degree does not always result in higher antioxidant activity. The use of ultrasound in the hydrolysis of these samples was seen to be effective, providing them with higher functionality and structural disruption.

Abstract Obtaining collagen and hydrolysates from mechanically separated chicken meat residue is an excellent way to add value to this waste. The aims of this study were to obtain collagen hydrolysates from chicken MSM residue using Alcalase® and Flavourzyme® enzymes, as well characterizing the functional, structural and thermal stability properties. The highest degree of hydrolysis was obtained using Alcalase®, 36.11%, while using Flavourzyme® resulted in 12.02%. The DSC analysis of the collagen indicated a denaturation temperature of 46.47 °C. The FTIR spectra of the crude collagen showed absorption peaks that were characteristic of amide bands A, B, I, II and III. In the spectra of the hydrolysed the area of the amide bands was reduced, and some peaks appeared between 800 and 1,200 cm-1. The disappearance of high molecular weight bands in the SDS-PAGE analysis also confirmed the hydrolysis of collagen. After the hydrolysis, the collagen presented reduced viscosity, the capacity to form foam, and foam stability. The emulsifying activity index was high in the hydrolysates in relation to the crude collagen. Thus, the use of Alcalase® and Flavourzyme® to obtain hydrolysates from collagen derived from chicken MSM residue was shown to be viable, and potentially useful for industrial applications.

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.

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.

RESUMO: Foram avaliados os efeitos da hidrólise enzimática (pepsina) assistida com ou sem ultrassom nas propriedades funcionais de hidrolisados de diferentes colágenos. Foi analisado o grau de hidrólise, a atividade antioxidante (DPPH) e a atividade antimicrobiana (MIC). O tratamento que possibilitou maior atividade antioxidante para a amostra fibra foi com a utilização de 4% de enzima e ultrassom concomitante (40,7%), levando a um grau de hidrólise de 21,7%. Para a amostra fibra pó o tratamento de hidrólise com uso de 4% de enzima resultou em menor teor de proteína (6,97mg/mL), maior grau de hidrólise (19,9%) e maior atividade antioxidante (38,6%). Os hidrolisados mostraram capacidade inibitória contra a bactéria gram-negativa Salmonella choleraesuis e gram-positiva Staphylococcus aureus. Pode-se concluir que a hidrólise enzimática concomitante, ou não, ao uso do ultrassom apresentou aumento da funcionalidade das amostras fibra e fibra pó. Para as demais amostras, sua utilização como tratamento complementar, a hidrólise não foi interessante, devido aos piores resultados de atividade antioxidante (DPPH) encontrados. Porém, proporcionou maior grau de hidrólise.

ABSTRACT: Enzymatic hydrolysis (pepsin) assisted with or without ultrasound in the functional properties of hydrolyzates from different collagens were analyzed. Degree of hydrolysis, antioxidant activity (DPPH) and antimicrobial activity (MIC) were assessed. The treatment that resulted in greater antioxidant activity for the fiber sample was with the use of 4% of enzyme and concomitant ultrasound (40.7%), leading to a degree of hydrolysis of 21.7%. For the powdered fiber sample the hydrolysis treatment with use of 4% of enzyme resulted in lower protein content (6.97mg/mL), higher degree of hydrolysis (19.9%) and greater antioxidant activity (38.6%). The hydrolyzates showed inhibitory capacity against gram-negative bacteria Salmonella choleraesuis and gram-positive bacteria Staphylococcus aureus. It can be concluded that enzymatic hydrolysis concomitant or not with the use of ultrasound increased the functionality of the fiber and powdered fiber samples, for the other samples its use as supplementary treatment was not productive, due to the worse results of antioxidant activity (DPPH) reported. However, it provided greater hydrolysis degree.

RESUMO: Este estudo teve como objetivo avaliar os efeitos da adição de cultura probiótica (Bifidobacterium animalis subsp. Lactis Bb-12) e prebióticos (fructooligosacarídeo - FOS) a formulações de iogurte armazenadas a 4°C por 28 dias, utilizando um planejamento experimental (variáveis independentes: (0-3% de FOS e cultura probiótica starter 0-3%). Foram analisados pH, acidez, gordura, sinérese, proteína, ºBrix, açúcares, FOS e contagem de bactérias probióticas. As formulações de iogurte adicionado de probiótico e prebiótico apresentaram menor acidez, sinérese e glicose quando comparados ao iogurte controle e também em comparação com as formulações contendo probiótico e prebiótico sozinhas. A formulação com 3% de probiótico e prebiótico apresentou menor perda de concentração de FOS e, após 28 dias, apresentou 1,5g de FOS por 100g (0,3% de kestose, 0,7% de nystose , 0,5% de fructosil-nistose). Além disso, a adição de prebióticos exerceu um efeito protetor sobre as bactérias probióticas e aumentou a sua sobrevivência.

ABSTRACT: This study aimed to evaluate the effects of adding probiotic culture (Bifidobacterium animalis subsp. Lactis Bb-12) and prebiotics (fructooligosaccharide - FOS) to yoghurt formulations stored at 4°C for 28 days, using an experimental design (independent variables: (0-3% of FOS and probiotic starter cultures 0-3%). The pH, acidity, fat, syneresis, protein, ºBrix, sugars, FOS and probiotic bacteria count were analyzed. The probiotic- and prebiotic-added yoghurt formulations showed lower acidity, syneresis and glucose than the control yoghurt and compared to formulations containing probiotic and prebiotic separately. The 3% probiotic and prebiotic formulation showed a lower loss of concentration of FOS, and after 28 days presented 1.5g of FOS per 100g (0.3% kestose, 0.7% nystose, 0.5% fructosyl-nystose). Furthermore, the addition of prebiotics exerted a protective effect on probiotic bacteria, enhancing their survival.

ABSTRACT Understanding the genetic structure and diversity of plants is fundamental to their conservation and permits their sustainable use by local communities. The genus Maytenus (Celastraceae) is composed of plants possessing pharmacological and antioxidant properties. However, the genetic and economic properties of the species M. dasyclada, a typical species of Araucaria forests in Brazil and Uruguay, have been little studied. In this work, the genetic structure and diversity of natural populations of M. dasyclada located in unprotected and preserved forest remnants were investigated using RAPD and isozymes markers. The results demonstrated that in areas of preservation, populations of M. dasyclada possess a relatively high degree of polymorphism and high values for Na, Ne, Shannon index, He and Ho, indicating high genetic variability. Moreover, these protected populations are very close to each other and potentially experience significant gene flow. The results presented here highlight the relevance of preservation areas for the conservation of M. dasyclada, and that populations inhabiting these areas could serve as a genetic source for the recovery of populations in regions where genetic diversity has been lost.

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.

ResumoObjetivo: Foi comparada a atividade da catalase em Smicridea McLachlan, 1871 (Insecta, Trichoptera) coletados em riachos margeados por vegetação ripária ou por atividades agrícolas e correlacionado o padrão da enzima com o conteúdo de metais na água.MétodosOs organismos foram coletados em pontos classificados como naturais (margeados por vegetação ripária) ou alterado/impactados (margeados por atividades agrícolas), localizados nas sub-bacias do Rio do Campo e do Rio do Cravo (RS, Brasil). Em seguida foram identificados e usados para determinação de proteínas e medida da atividade da catalase. A concentração de Mg, Cr, Cu, Pb e Cd na água foi determinada por espectrometria de absorção atômica.ResultadosA atividade da catalase em Smicridea variou entre 1,5 e 6 U, com valores médios de 2,63 ± 0,096 U (EP). A presença de metais foi maior nos riachos localizados na matriz agrícola, exceto para o Mg na sub-bacia do Rio Cravo e Cu na sub-bacia do Rio Campo. A atividade da catalase foi maior em Smicridea coletados nos locais margeados por vegetação ripária em relação aos margeados por agricultura, e foi negativamente correlacionada com os níveis de Pb e Cd.ConclusõesOs dados mostram o potencial da catalase como ferramenta complementar em estudos de biomonitoramento da qualidade de água usando Smicridea como bioindicador.

Aim: We compare catalase activity in SmicrideaMcLachlan, 1871 (Insecta, Trichoptera) collected in natural and agricultural streams and correlates the enzyme pattern with metal content in the water.MethodsOrganisms were collected in sites classified as natural (riparian vegetation in buffer zone) and altered/impacted (agricultural land use in drainage area) environments, located at Cravo River and Campo River sub-basins (RS, Brazil). Next the collected larvae were identified and used to proteins quantification and catalase activity measure. The concentration of Mg, Cr, Cu, Pb and Cd in the water was determined by atomic absorption spectrometry.ResultsCatalase activity in Smicridea ranged from 1.5 to 6 U, with mean values about 2.63 ± 0.096 U (SEM). The presence of metals was higher in the streams located at agricultural drainage area, except for Mg at the Cravo sub-basin and Cu at the Campo sub-basin. Catalase was higher in Smicridea collected in natural streams as compared to that agriculture streams and was correlated with Pb and Cd levels.ConclusionsThe data showed the potential of this biomarker as a useful tool for complementation of water quality biomonitoring studies using Smicridea as bioindicator.

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.