Behavior study of Bifidobacterium longum using solid state fermentation from commercial soybean meal

The development of alternatives to dairy products has gained great importance using plant-based foods. In this study, efforts have been made to develop vegetable alternatives from soybean paste without any supplement using single potential probiotic culture. Commercial soybean meal was inoculated with Bifidobacterium (B.) longum under previously fitted fermentation conditions by experimental design. Carbohydrates, organic acids, isoflavones, and amino acids profiles were studied in nine conditions of moisture and temperature, and also at several times in optimized conditions. Kinetics and technological parameters, effect of simulated gastric conditions on bacterium survival in optimized soybean paste, and their relationship with soybean matrix using scanning electron microscopy (SEM) were also evaluated. B. longum was able to use the main carbohydrates in soybean producing organic acids as was expected (acetic/lactic ∼ 1.5) and to enhance bioactive isoflavones (maximum concentration: 32.6 mg/50 g of soybean paste). Furthermore, B. longum showed high tolerance at simulated saliva solution and gastric juice, but the pancreatic solution deeply affected its viability in MRSs and also in soybean paste. Soybean paste represents an excellent vegetable candidate to be used as potential probiotic carrier food for B. longum and an attractive alternative to develop new functional foods.Fil: Rodríguez de Olmos, Antonieta. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; ArgentinaFil: Garro, Oscar Alfredo. Consejo Nacional de Investigaciones Cientificas y Tecnicas. Centro Cientifico Tecnologico Conicet - Nordeste. Instituto de Investigaciones En Procesos Tecnologicos Avanzados. - Universidad Nacional del Chaco Austral. Instituto de Investigaciones En Procesos Tecnologicos Avanzados.; ArgentinaFil: Garro, Marisa Selva. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Centro de Referencia para Lactobacilos; Argentin

Effect of temperature, pH and NaCl on nisin activity against <i>Lactobacillus fructivorans</i>

The aim of this work was to determine the influence of pH, sodium chloride concentration and the combination of different temperatures and periods of exposure on the antimicrobial activity against Lactobacillus fructivorans. Turbidity of the different system conditions was monitored in order to establish the microorganism growth. The effect of temperatures ranging from 60 to 120ºC during periods of 10 to 60 minutes was evaluated. Nisin activity was only changed by temperatures ranging from 100 to 120ºC, in several exposure times. A pH range between 3.5 and 7 was tested. The highest inhibitory effect was recorded for neutral pH and lightly acidic conditions. Sodium chloride concentrations studied were 1 and 2 % w/v. The latter value helped to enhance the inhibitory effect of the bacteriocin. These results show the influence that the studied factors exert on nisin activity against L. fructivorans and suggest that they have to be taken into account when nisin is to be used as a biopreservative in food.El presente trabajo tuvo como objetivo determinar la influencia del pH, concentración de cloruro de sodio y la combinación de diferentes temperaturas y períodos de exposición sobre la actividad antimicrobiana de nisina s obre una bacteria alterante Lactobacillus fructivorans. El crecimiento del microorganismo bajo diferentes condiciones fue determinado por la presencia de turbidez. Se evaluó el efecto de la temperatura en un rango de 60 a 120ºC durante períodos de 10 a 60 minutos. La actividad de la nisina fue afectada solamente por temperaturas de 100 y 120ºC, a cualquier tiempo de exposición considerado. Los ensayos se realizaron con un rango de pH entre 3,5 y 7. El mayor efecto inhibitorio fue a pH neutro y levemente ácido. Las concentraciones de cloruro de sodio fueron de 1 y 2% p/v. Sólo a la mayor concentración se ve un incremento en la actividad inhibitoria de la bacteriocina. Estos resultados muestran la influencia que los factores estudiados ejercen sobre la actividad de la bacteriocina frente a L. fructivorans e indican que tales factores deben ser tenidos en cuenta cuando la nisina sea usada en la preservación de alimentos.Centro de Investigación y Desarrollo en Ciencias Aplicada

Production of Pectinolytic Enzymes by the Yeast Wickerhanomyces anomalus Isolated from Citrus Fruits Peels

Wickerhamomyces anomalus is pectinolytic yeast isolated from citrus fruits peels in the province of Misiones, Argentine. In the present work, enzymes produced by this yeast strain were characterized, and polygalacturonase physicochemical properties were determined in order to evaluate the application of the supernatant in the maceration of potato tissues. W. anomalus was able to produce PGin liquid mediumcontaining glucose and citrus pectin,whosemode of actionwas mainly of endo type.The supernatant did not exhibit esterase or lyase activity. No others enzymes, capable of hydrolyzing cell wall polymers, such as cellulases and xylanases,were detected. PGshowedmaximal activity atpH4.5 and at temperature range between 40∘Cand50∘C. It was stable in the pH range from3.0 to 6.0 and up to 50∘Cat optimumpH.The enzymatic extractmacerated potato tissues efficiently.Volume of single cells increased with the agitation speed.The results observed make the enzymatic extract produced by W. anomalus appropriate for future application in food industry, mainly for the production of fruit nectars or mashed of vegetables such as potato or cassava, of regional interest in the province of Misiones, Argentine.Fil: Martos, María Alicia. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; ArgentinaFil: Zubreski, Emilce R.. Universidad Nacional de Misiones. Facultad de Ciencias Exactas, Químicas y Naturales; ArgentinaFil: Garro, Oscar Alfredo. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Microbiologia de Alimentos; ArgentinaFil: Hours, Roque Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico la Plata. Centro de Investigación y Desarrollo En Fermentaciones Industriales (i); Argentin

Assessment of the Quality and Shelf-Life in Enriched n3 PUFA Raw Beef Patties Using Dry Soybean Sprouts as Antioxidant

The appearance of fresh meat is a major determinant of its appeal to consumers. Ground beef in retail display oxidizes at a faster rate than whole muscle products; the use of antioxidants to break the radical chain reaction in the oxidation process is an effective method for slowing oxidation. Soybean is a complex matrix with several bioactive compounds, including peptides and proteins, isoflavones, saponins, and other compounds with antioxidant properties. This study was conducted for 1) to evaluate the antioxidant properties of dry soybeans sprouts (DSS) from Glycine max (L.) Merr., MUNASQA®; 2) to evaluate quality characteristics of raw beef patties added with dried soybean sprouts at different levels (0.5%, 1% and 2%) and soybean oil as replacer of fat; and 3) to estimate color changes and lipid oxidation of n3 fortified raw beef under frozen storage. Results showed that dry soybean sprouts had a high level of superoxide dismutase enzyme, high total phenolics and flavonoids content and appreciable vitamin c content. Although reduction power was low, 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2?-azino-bis(3-ethylbenzthiazoline-6- sulphonic acid) (ABTS) radicals scavenging activity were elevated. When different concentrations of DSS were incorporated to enriched beef patties with soybean oil, the nutritional value was slightly affected, while that n3 and n6 fatty acid content were increased around three twice. The beef patties formulated with 1% of natural antioxidant showed significantly (p < 0.05) better color stability than those without antioxidants. The lipid oxidation was inhibited in all cases, and was strongly effective at 1% concentration of DSS being the reduced percent of thiobarbituric acid reactive substances (TBARS) comparable to butilated hydroxianisole (BHA). The results shown in this research suggest that dry soybeans sprouts could also be used as a cheap natural antioxidant source for meat products.Fil: Romero, Mara Cristina. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Industrias Alimentarias Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garro, Oscar Alfredo. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Microbiología de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Romero, Ana María. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Industrias Alimentarias Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Michaluk, Ariel German. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Industrias Alimentarias Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Doval, Mirtha Marina. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Industrias Alimentarias Ii; ArgentinaFil: Judis, Maria Alicia. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Industrias Alimentarias Ii; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Calidad alimenticia y estabilidad oxidativa de pseudoplatystoma corruscans

De todos los tipos de carnes, la del pescado es la más susceptible a la autolisis, a la oxidación e hidrólisis de las grasas, y a la alteración por microorganismos. El surubí manchado (Pseudoplatystoma corruscans) es el pez de agua dulce más comercializado en el noreste argentino. Los ejemplares analizados provinieron del río Paraná, 27° 17´ 30´´ latitud sur y 58° 59 50 de longitud oeste. Las muestras se envasaron en películas de alta y baja permeabilidad al oxígeno y se almacenaron a 16 °C y 5 °C. Se realizaron determinaciones fisicoquímicas, UFC, Valor de peróxido y TBARS, cada 7 días en las muestras refrigeradas y cada 14 días en las congeladas. El recuento inicial de microorganismos fue de 1,25.10+05. Al cabo de 2 semanas las muestras refrigeradas ya no fueron aptas microbiológicamente para el consumo (1.10+07). Para atenuar el crecimiento microbiano y retardar la oxidación lipídica deben emplearse temperaturas de congelación y envases de baja permeabilidad al oxígeno.De todos los tipos de carnes, la del pescado es la más susceptible a la autolisis, a la oxidación e hidrólisis de las grasas, y a la alteración por microorganismos. El surubí manchado (Pseudoplatystoma corruscans) es el pez de agua dulce más comercializado en el noreste argentino. Los ejemplares analizados provinieron del río Paraná, 27° 17’ 30” latitud sur y 58° 59’ 50” de longitud oeste. Las muestras se envasaron en películas de alta y baja permeabilidad al oxígeno y se almacenaron a –16 °C y 5 °C. Se realizaron determinaciones fisicoquímicas, UFC, Valor de Peróxido y TBARS, cada 7 días en las muestras refrigeradas y cada 14 días en las congeladas. El recuento inicial de microorganismos fue de 1,25.10+05. Al cabo de 2 semanas las muestras refrigeradas ya no fueron aptas microbiológicamente para el consumo (1.10+07). Para atenuar el crecimiento microbiano y retardar la oxidación lipídica deben emplearse temperaturas de congelación y envases de baja permeabilidad al oxígeno.De todolos tipos de carnes, á do pescado é a máis susceptible á autolisis, á oxidación e hidrólisis das grasas, e á alteración por microorganismos. O surubí manchado (Pseudoplatystoma corruscans) e o peixe de auga dulce máis comercializado no noreste argentino. Os exemplares analizados proveñeron do río Paraná, 27° 17’ 30” latitude sur e 58° 59’ 50” lonxitude oeste. As mostras envasaronse en películas de alta e baixa permeabilidade ó oxíxeno e almacenaron-se a -16 °C e 5 °C. Realizaronse determinacións fisicoquímicas, UFC, Valor de Peróxido e TBARS, cada 7 días nas mostras refrixeradas e cada 14 días nas conxeladas. O reconto inicial de microorganismos foi de 1,25.10+05. O cabo de 2 semanas as mostras refrixeradas xa non foron aptas microbiolóxicamente para o consumo (1.10+07). Para atenuar o crecemento microbiano e retardar a oxidación lipídica deben emplearse temperaturas de conxelación e envases de baixa permeabilidade ó oxíxeno.Fil: Molina, M.R... Universidad Nacional del Nordeste. Facultad de Agroindustrias; ArgentinaFil: Garro, Oscar Alfredo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Nordeste; ArgentinaFil: Judis, Maria Alicia. Universidad Nacional del Nordeste. Facultad de Agroindustrias; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Partial characterization of enzymatic activities produced by a wild strain of <i>A. niger</i>

Aspergillus niger, isolated from decay citrus peels in the province of Misiones, was able to produce pectinases by submerged fermentation. The enzymatic extract exhibited polygalacturonase, pectinesterase and lyase activities. Others enzymes capable of degrading cell wall polymers were also detected in the enzymatic extract such as cellulases and xylanases. Polygalacturonase was an endo-polygalacturonase. The enzyme exhibited a maximal activity at pH range between 4.5 to 5.0, was stable in the pH range from 2.5 to 5.5 and remained unchanged when was incubated at temperatures lower than 50 ºC. The fungi produced three PG isoenzymes. The enzymatic extract was able to clarify apple juice. The results observed make the pectinolytic enzymes produced by A. niger appropriate for future application in fruit juice processing industries.Centro de Investigación y Desarrollo en Fermentaciones Industriale

Isolation of a yeast strain able to produce a polygalacturonase with maceration activity of cassava roots

The objective of the present study was the isolation of a yeast strain, from citrus fruit peels, able to produce a polygalacturonase by submerged fermentation with maceration activity of raw cassava roots. Among 160 yeast strains isolated from citrus peels, one strain exhibited the strongest pectinolytic activity. This yeast was identified as Wickerhamomyces anomalus by 5.8S-ITS RFLP analysis and confirmed by amplification of the nucleotide sequence. The yeast produced a polygalacturonase (PG) in Erlenmeyer shake flasks containing YNB, glucose, and citrus pectin. PG synthesis occurred during exponential growth phase, reaching 51 UE.mL-1 after 8 hours of fermentation. A growth yield (Yx/s) of 0.43 gram of cell dry weight per gram of glucose consumed was obtained, and a maximal specific growth rate (μm) of 0.346 h-1 was calculated. The microorganism was unable to assimilate sucrose, galacturonic acid, polygalacturonic acid, or citrus pectin, but it required glucose as carbon and energy source and polygalacturonic acid or citrus pectin as inducers of enzyme synthesis. The crude enzymatic extract of Wickerhamomyces anomalus showed macerating activity of raw cassava. This property is very important in the production of dehydrated mashed cassava, a product of regional interest in the province of Misiones, Argentina.Centro de Investigación y Desarrollo en Fermentaciones Industriale

Partial characterization of enzymatic activities produced by a wild strain of <i>A. niger</i>

Aspergillus niger, isolated from decay citrus peels in the province of Misiones, was able to produce pectinases by submerged fermentation. The enzymatic extract exhibited polygalacturonase, pectinesterase and lyase activities. Others enzymes capable of degrading cell wall polymers were also detected in the enzymatic extract such as cellulases and xylanases. Polygalacturonase was an endo-polygalacturonase. The enzyme exhibited a maximal activity at pH range between 4.5 to 5.0, was stable in the pH range from 2.5 to 5.5 and remained unchanged when was incubated at temperatures lower than 50 ºC. The fungi produced three PG isoenzymes. The enzymatic extract was able to clarify apple juice. The results observed make the pectinolytic enzymes produced by A. niger appropriate for future application in fruit juice processing industries.Centro de Investigación y Desarrollo en Fermentaciones Industriale

Partial characterization of enzymatic activities produced by a wild strain of <i>A. niger</i>

Aspergillus niger, isolated from decay citrus peels in the province of Misiones, was able to produce pectinases by submerged fermentation. The enzymatic extract exhibited polygalacturonase, pectinesterase and lyase activities. Others enzymes capable of degrading cell wall polymers were also detected in the enzymatic extract such as cellulases and xylanases. Polygalacturonase was an endo-polygalacturonase. The enzyme exhibited a maximal activity at pH range between 4.5 to 5.0, was stable in the pH range from 2.5 to 5.5 and remained unchanged when was incubated at temperatures lower than 50 ºC. The fungi produced three PG isoenzymes. The enzymatic extract was able to clarify apple juice. The results observed make the pectinolytic enzymes produced by A. niger appropriate for future application in fruit juice processing industries.Centro de Investigación y Desarrollo en Fermentaciones Industriale

Indigenous starter cultures to improve quality of artisanal dry fermented sausages from Chaco (Argentina)

Lactic acid bacteria (LAB) and coagulase negative cocci (CNC) were isolated from artisanal dry sausages sampled from the northeastern region of Chaco, Argentina. In order to evaluate their performance in situ and considering technological features of the isolated strains, two mixed selected autochthonous starter cultures (SAS) were designed: (i) SAS-1 (Lactobacillus sakei 487 + Staphylococcus vitulinus C2) and (ii) SAS-2 (L. sakei 442 + S. xylosus C8). Cultures were introduced into dry sausage manufacturing process at a local small-scale facility. Microbiological and physicochemical parameters were monitored throughout fermentation and ripening periods, while sensory attributes of the final products were evaluated by a trained panel. Lactic acid bacteria revealed their ability to colonize and adapt properly to the meat matrix, inhibiting the growth of spontaneous microflora and enhancing safety and hygienic profile of the products. Both SAS showed a beneficial effect on lipid oxidation and texture of the final products. Staphylococcus vitulinus C2, from SAS-1, promoted a better redness of the final product. Sensory profile revealed that SAS addition preserved typical sensory attributes. Introduction of these cultures could provide an additional tool to standardize manufacturing processes aiming to enhance safety and quality while keeping typical sensory attributes of regional dry fermented sausages.Fil: Palavecino Prpich, Noelia Zulema. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Microbiología de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Castro, Marcela Paola. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Microbiología de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Cayre, María Elisa. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Microbiología de Alimentos; ArgentinaFil: Garro, Oscar Alfredo. Universidad Nacional del Chaco Austral. Departamento de Ciencias Basicas y Aplicadas. Laboratorio de Microbiología de Alimentos; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vignolo, Graciela Margarita. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucuman. Centro de Referencia Para Lactobacilos; Argentin