Propiedades nutritivas y tecno funcionales de barras de pseudocereales adicionadas con soya, mango y granada / Nutritional and techno functional properties of pseudocereal bars added with soy, mango and pomegranate

Las barras de cereal (BC), se comercializan como un snack saludable, no obstante, su calidad nutricional es baja. Una alternativa para mejorar esto, es la incorporación de ingredientes como pseudocereales, germinados y subproductos de fruta. Objetivo. Evaluar el contenido nutricional y propiedades tecnofuncionales de una barra de cereal formulada a partir de pseudocereales, germinados de soya y subproductos del procesamiento de frutas. Materiales y Métodos. Se desarrollaron 6 formulaciones (F0-F5). Se determinó el contenido de proteína y fibra cruda, se seleccionó la formulación que presentó el mayor contenido de estos componentes. A la BC seleccionada se le determinó la digestibilidad in-vitro de la proteína, las propiedades tecnofuncionales potencial prebiótico y actividad inhibitoria de ECA-I. Resultados. La formulación seleccionada fue F1 (13,6 g/100 g p.s. proteína y 13,1 g/100 g p.s. fibra cruda). La digestibilidad de la proteína fue del 69 %, el cual es cercano a valores reportados para algunos componentes de la BC. La capacidad de hinchamiento y retención de agua fue 2,55 ml/g; 12,74 %, respectivamente. El crecimiento de L. brevis en medio MRS modificado con BC no presentó diferencias estadísticas con el medio control, indicando el potencial prebiótico presente en la BC. La barra de cereal tuvo un 39% de actividad inhibitoria de ECA-I, demostrando la acción de los compuestos bioactivos posiblemente liberados durante la digestión de la BC. Conclusión. La formulación desarrollada presenta propiedades funcionales importantes y podría generar beneficios para la salud(AU)

Introduction. Cereal bars (CB) are marketed as a healthy snack; however, their nutritional quality is low. An alternative to improve this is the incorporation of ingredients such as soybean sprouts, which have a higher protein content than some seeds; as well as fruit by-products that contain important bioactive compounds. Objective. To evaluate the nutritional content and techno-functional properties of a cereal bar formulated from pseudocereals, soybean sprouts, and fruit processing by-products. Materials and Methods. 6 formulations (F0-F5) were developed. The content of protein and crude fiber was determined, the formulation that presented the highest content of these components was selected. The in-vitro digestibility of the protein, the technofunctional properties, potential prebiotic and inhibitory activity of ACE-I were determined for the selected BC. Results. The selected formulation was F1 (13.6g/100g p.s. protein and 13.1g/100 g p.s. crude fiber). Protein digestibility was 69%, which is close to reported values for some CB components. The swelling and water retention capacity was 2.55 ml/g; 12.74%, respectively. The growth of L. brevis in modified MRS medium with CB did not present statistical differences with the control medium, indicating the prebiotic potential present in CB. The cereal bar had 39% ACE-I inhibitory activity, demonstrating the action of bioactive compounds possibly released during CB digestion. Conclusion. The developed formulation has important functional properties and could generate health benefits(AU)

Evaluación calórica y sensorial de una mezcla para helado formulado con inulina como sustituto parcial de grasa / Sensory and calorie evaluation of an ice cream mix, where inulin is incorporated as a partial substitute for fat

RESUMEN Se evaluó el aporte calórico, el contenido de grasa saturada y la aceptación sensorial de helados de vainilla formulados con inulina, como sustituto parcial de grasa saturada. Se formularon por triplicado cuatro mezclas para helados, en las cuales, se reemplazó parte de la grasa de palma (2, 3 y 4%) por inulina comercial. La grasa del tratamiento control, se formuló con 7% de grasa vegetal saturada. Para el reemplazo, se utilizó una relación 1:0,25 (grasa saturada:inulina). El aporte calórico, se calculó mediante la medición de energía bruta. El análisis sensorial, se realizó con 23 jueces consumidores habituales de helado. Se concluyó que en la formulación de helados de vainilla es posible reemplazar el 57,14% de grasa vegetal saturada por inulina sin que se afecten las propiedades sensoriales en el producto, logrando reducir en un 16%, el contenido calórico y, en 48,6%, el contenido de grasa saturada. Por lo tanto, la sustitución de grasa vegetal por inulina es una alternativa, que permite ofrecer en el mercado helados funcionales, con bajo contenido calórico, sin perder la palatabilidad, que hace a los helados un producto placentero para la gran mayoría de la población mundial.

ABSTRACT The caloric intake, saturated fat content and sensory acceptance of vanilla ice cream formulated with inulin as a partial substitute for saturated fat was evaluated. Ice cream mixtures by triplicate were formulated, and part of the palm fat (2, 3 and 4%) was replaced by commercial inulin. The fat of the control treatment was formulated with 7% vegetable fat. For the replacement of fat, a ratio of 1: 0.25 (fat: inulin) was used. The caloric intake was calculated by measuring gross energy. The sensory analysis was carried out with 23 habitual consumers judges of ice cream. It was concluded that in the formulation of vanilla ice cream is possible to replace 57.14% vegetable fat for inulin without affecting the sensory properties in the product, with this is possible to obtain 16% reduction in the caloric content and 48.6% in the content of saturated fat. Therefore, the replacement of vegetable fat by inulin is an alternative that allows offering functional ice cream with low caloric content, without losing the palatability that makes ice cream pleasant for most of the world population.

Influencia de agentes crioprotectores sobre las cinéticas de congelación de lechuga (Lactuca sativa L.) / Influence of cryoprotective agents on lettuce freezing kinetics (Lactuca sativa L.)

RESUMEN La lechuga es una hortaliza de hoja que no resiste la congelación. Como una alternativa de conservación de lechuga Lactuca sativa L. "Lollo Bionda", se evaluó el efecto de la aplicación de crioprotectores sobre cada una de las etapas de congelación de lechuga. En cada etapa, se evaluó el tiempo de duración, la velocidad y la temperatura de congelación. Como crioprotectores, se utilizaron soluciones de Aloe (Aloe barbadensis Miller), a concentraciones de 70, 80 y 90%; almidón, a concentraciones de 0,5, 1 y 2% p/p y aceite de oliva. Las muestras, se impregnaron con los diferentes crioprotectores y se ultracongelaron. Las temperaturas del material vegetal, se registraron durante una hora, con intervalos de 5s; se construyeron las cinéticas de congelación y sobre las cinéticas, se identificaron las diferentes etapas de congelación. Se encontró que el tipo y la concentración del crioprotector altera, de manera estadísticamente significativa, la temperatura, el tiempo y la velocidad de cada una de las etapas de congelación. Las mayores concentraciones de solutos presentes en Aloe vera al 90%, almidón al 2% y aceite de oliva influyeron considerablemente en la acción crioprotectora de la lechuga.

ABSTRACT Lettuce is a leafy vegetable that does not resist freezing. As an alternative to the lettuce Lactuca sativa L. "Lollo Bionda" lettuce conservation, the effect of the application of cryoprotectants on each of the freezing stages of lettuce was evaluated. In each stage, duration time, speed and freezing temperature were evaluated. Aloe (Aloe barbadensis Miller) solutions at concentrations of 70, 80 and 90%, starch at concentrations of 0.5, 1 and 2% w / w and olive oil were used as cryoprotectants. The samples were impregnated with the different cryoprotectants and deep-frozen. The temperatures of the plant material were recorded for one hour at intervals of 5 s, the freezing kinetics were built and, on the kinetics, the different stages of freezing were identified. It was found that the type and concentration of the cryoprotectant alters in a statistically significant way the temperature, time and speed of each of the freezing stages. The highest concentrations of solutes present in 90% Aloe vera, 2% starch and olive oil significantly influenced the cryoprotective action of lettuce.

Double emulsion and complex coacervation in stevia encapsulation / Doble emulsión y coacervacion compleja en la encapsulación de estevia

Background: Stevia leaves a residual flavor at moment of being consumed, and its sweet taste remains little time, whereby, encapsulation is an option to mitigate these problems. Objective: Evaluate the double emulsion system followed by complex coacervation in stevia encapsulation. Methods: The effect of the concentration of the sweetener was determined (3.5; 5; 7.5 and 10% p/p) as well as the concentration of the wall material (2.5 and 5% p/p), on the morphology, capsules size, and encapsulation capacity. The double emulsion was prepared, the coacervate was formed, and then capsules were lyophilized. The morphology and capsule size were measured before and after lyophilization by optical microscopy. From Fourier´s infrared transformed spectrometry, encapsulation capacity was analyzed. Water activity and solubility were measured in lyophilized capsules. Results: Micro and nanocapsules (minimum size of 19.39 ± 0.74µm and 62.33 ± 6.65µm maximum) were obtained. Micrographs showed that the encapsulation technique used, allows obtaining dispersed stevia capsules and those of round and homogeneous morphology. The encapsulation capacity was 84.37 ± 4.04%. The minimum value of water activity was 0.49 ± 0.01 and 17.65 ± 0.91% of solubility. Conclusions: An increased in encapsulation capacity was obtained when the highest concentration of the wall material was used. The capsule diameter increased as the sweetener concentrations increased. The formulation to 5% (p/p) of stevia and 5% (p/p) in wall material was associated with better controlled release of the sweetener, which allows establishing subsequent applications in which the sweet taste is prolonged and the stevia bitter taste concealed.

Antecedentes: La estevia deja sabor residual al ser consumida, y su sabor dulce permanece poco tiempo, por lo cual, la encapsulación es una opción para mitigar estos problemas. Objetivo: Se evaluó el sistema doble emulsión seguido por coacervación compleja en la encapsulación de estevia. Métodos: Se determinó el efecto de la concentración del edulcorante (3.5; 5; 7.5 y 10% p/p) y de la concentración del material de pared (2.5 y 5% p/p), en la morfología, tamaño de cápsulas, y capacidad de encapsulación. Se elaboró la doble emulsión, se formó el coacervado, y posteriormente, las cápsulas se liofilizaron. La morfología y el tamaño de las cápsulas, se midieron antes y después de la liofilización mediante microscopia óptica. A partir de espectrometría infrarroja de transformada de Fourier se analizó capacidad de encapsulación. En las cápsulas liofilizadas se midió actividad de agua y solubilidad. Resultados: Se obtuvieron micro y nanocápsulas (tamaño mínimo de 19.39±0.74µm y máximo 62.33±6.65µm). Las micrografías indicaron que la técnica de encapsulación usada, permite obtener cápsulas de estevia dispersas y de morfología redonda y homogénea. La capacidad de encapsulación fue 84.37±4.04%. El valor mínimo de actividad de agua fue 0.49±0.01, y solubilidad de 17.65±0.91%. Conclusiones: Se obtuvo incremento en la capacidad de encapsulación cuando se utilizó la mayor concentración del material de pared. El diámetro de las cápsulas aumentó a medida que se incrementaron las concentraciones del edulcorante. Se concluyó que la formulación a 5% (p/p) de edulcorante y de 5% (p/p) en material de pared fue el tratamiento que mejor se asocia a una liberación controlada de estevia, lo cual permite establecer posteriores aplicaciones en las que se prolongue el sabor dulce y enmascare el sabor amargo de la estevia.

Infusão intramamária de Weissella confusa afeta a contagem de células somáticas e a contagem diferencial de leucócitos no leite / Intramammary infusion of Weissella confusa affects somatic cell counts and milk differential leukocyte count

A utilização de bactérias do ácido láctico (LAB) como uma alternativa ao uso de antimicrobianos tem sido proposta para o controle da mastite bovina. No entanto, antes dessas aplicações, o efeito in vivo das LAB sobre a glândula deve ser cuidadosamente avaliado. O objetivo deste estudo foi determinar se a infusão intramamária de Weissella confusa e seus metabólitos em vacas afeta a contagem de células somáticas (CCS) e a contagem diferencial de leucócitos no leite. Vinte e quatro tetos de seis vacas Hartón del Valle foram selecionados para a pesquisa. Uma alíquota de 5mL de uma solução aquosa de células de W. confusa (W) (concentração 109u.f.c. mL-1), 5mL de células de W. confusa com seus metabólitos (W + W10b) ou 5mL de metabólitos (W10b) foi aplicada ao acaso em três tetos de cada vaca. O teto restante em cada úbere representou a unidade experimental de controle (C). Nos dias 1, 2, 3, 5, 7, 9, 13 e 15 após infusão (PI), a CCS, o pH, a acidez titulável e a contagem diferencial de leucócitos no leite foram avaliadas. A aplicação das três substâncias biológicas produziu aumentos significativos na CCS, no pH e na contagem de neutrófilos polimorfonucleares. Não foram encontradas diferenças significativas entre W e W+W10b. O W10b mostrou a menor alteração sobre as variáveis avaliadas. Os resultados sugerem que a aplicação de W. confusa e seus metabólitos afeta a CCS e a contagem diferencial de leucócitos no leite.

The use of lactic acid bacteria (LAB) as an alternative to antimicrobial usage has been proposed for the control of bovine mastitis. However, before its application, the in vivo effects of the LAB on mammary gland must be carefully evaluated. The objective of this study was to determine whether the intramammary infusion of Weissella confusa and its metabolites in cows affects the somatic cell counts (SCCs) and milk differential leukocyte count. Twenty-four mammary quarters of six Hartón del Valle cows were selected for the investigation. A 5mL aliquot of an aqueous solution of W. confusa cells (W) (concentration of 109cfu mL-1), 5mL of W. confusa cells with its metabolites (W+W10b) or 5mL of metabolites (W10b) was randomly applied to three mammary quarters of each cow. The remaining teat on each udder represented the experimental control units (C). At 1, 2, 3, 5, 7, 9, 13 and 15 days post-infusion (PI), the SCCs, pH, titrable acidity and milk differential leukocyte count were evaluated. The application of the three biological substances produced significant increases in SCCs, pH and polymorphonuclear neutrophil counts. No significant differences between W and W+W10b infusion were found. W10b resulted in a lesser alteration on the variables evaluated. The results suggest that the intramammary infusion of W. confusa and its metabolites affect the SCCs and milk differential leukocyte count in cows.

Viabilidad de una bacteria láctica encapsulada e incorporada en una matriz de cobertura de chocolate / Viability of encapsulated lactic bacteria added in a matrix of chocolate coverage

Se evaluó la viabilidad durante el almacenamiento de Weissella confusa incorporada en una matriz de cobertura de chocolate. La bacteria probiótica se encapsuló empleando tres materiales de pared, gel de Aloe vera, gel Aloe vera + Almidón al 10 % y gel de Aloe vera + Almidón al 15 % y células libres como control. Posteriormente se liofilizó. La bacteria probiótica encapsulada, se incorporó en una matriz de cobertura de chocolate. Los chips se empacaron y almacenaron durante 5 semanas a 4 °C, cada semana se midieron cambios en la viabilidad de la bacteria probiótica y en la actividad de agua. En la quinta semana, los chips se sometieron a condiciones simuladas de jugos intestinales. Durante el almacenamiento los chips mantuvieron su carácter probiótico (>10(6) UFC/g), sin embargo, cuando la bacteria probiótica se encapsuló en gel aloe vera, se obtuvo mayor número de bacterias probióticas vivas dentro de la matriz sólida (2,1x10(8) UFC/g). La actividad de agua varió de 0,470 a 0,810. La bacteria probiótica permaneció viva por 2 horas en medios simulados de jugos intestinales, lo cual ratifica que la matriz sólida y los medios de encapsulación seleccionados son adecuados para el desarrollo de productos sólidos probióticos ricos en grasa vegetal.

Viability during storage of Weissella confusa incorporated in a chocolate coating matrix was evaluated. Probiotic bacteria was encapsulated using three wall materials, Aloe vera gel, Aloe vera gel + 10 % starch and aloe vera gel + 15 % starch and free cells as control. Subsequently lyophilized. Probiotic bacteria encapsulated, was incorporated into a chocolate coating matrix. The chips were packed and stored for 5 weeks at 4 °C, were measured weekly changes in viability of the probiotic bacteria and water activity. In the fifth week, the chips were subjected to simulated conditions of intestinal juices. During storage chips remained probiotic character (>10(6) CFU/g), however, if the probiotic bacteria are encapsulated in aloe vera gel, the greater number of living probiotic bacteria was obtained within the solid matrix (2,1x10(8) CFU/g ). Water activity ranged from 0.470-0,810. Probiotic bacteria remained alive for 2 hours in simulated intestinal fluid media, which confirms that the solid matrix and the selected encapsulation means are suitable for the development of solid product rich in vegetable fat probiotics.

Actividad antimicrobiana de Weissella confusa y sus metabolitos frente a Escherichia coli y Klebsiella pneumoniae / Antimicrobial activity of Weisella confusa and its metabolites against Escherichia coli and Klebsiella pneumoniae

Con el fin evaluar el campo de aplicación potencial de una bacteria ácido láctica y de sus metabolitos, se realizó la cinética de la actividad antimicrobiana de W. confusa y de sus metabolitos contra E. coli, y K. pneumoniae, dos patógenos causantes de enfermedades transmitidas por alimentos. La producción de W. confusa se realizó por fermentación discontinua en sustrato comercial MRS. Se realizaron tres fermentaciones durante 6 horas, sin aireación, agitación continúa 33°C y 100 rpm. Cada hora de fermentación se separaron tres sustancias biológicas, W. confusa con sus metabolitos (W+W10b), células de W. confusa libres de metabolitos (W) y metabolito (W10b) y se midió la actividad antimicrobiana contra los patógenos E. coli, y K. pneumoniae. Se encontraron diferencias estadísticas significativas entre tratamientos y tiempo de fermentación. Para E. coli el tratamiento W presentó la mayor actividad antimicrobiana, la cual se obtuvo entre la cuarta y sexta hora de fermentación (2.45 cm de diámetro promedio de inhibición). Para K. pneumoniae, los tratamientos W y W+W10b presentaron actividad antimicrobiana entre la cuarta y quinta hora de fermentación, sin diferencia significativa entre ellos. W. confusa y el metabolito W10b demostraron poseer capacidad antimicrobiana contra E. coli y K. pneumoniae, lo cual sugiere que W. confusa y W10b podrían utilizarse como alternativa de bioconservación o bioprotección de alimentos frescos y procesados, para alimentación humana y animal; y podría convertirse en una alternativa al uso de antibióticos para enfermedades causadas por E. coli y K. pneumoniae.

The kinetic of antimicrobial activity of Weissella confusa and their metabolites against E. coli, and K. pneumoniae, (two pathogens causing foodborne illness) was evaluated, in order to know the possible use in food processing. W. confusa was produced by batch fermentation using MRS commercial substrate. Three fermentations, of 6 hours at 33 °C, without aeration, stirring continuously (100 rpm) were performed. Every hour of fermentation, three biological substances, W. confusa with their metabolites (W + W10b), W. confusa free cells metabolites (W), and metabolite (W10b) were separated, and subsequently the antimicrobial activity against pathogenic E. coli and K. pneumoniae was measured. Statistically significant differences between treatments and fermentation time were found. Treatment (W) against E. coli, showed the greatest antimicrobial activity, it was obtained between the fourth and sixth hours of fermentation (2.45 cm diameter average inhibition). In treatments W and W + W10b against K. pneumoniae, statistically significant differences between them were not found. The antimicrobial activity was shown between the fourth and fifth hour of fermentation. W. confusa and W10b have antimicrobial activity against E. coli and K. pneumoniae, suggesting that W and W10b could be used as an alternative to biopreservation or bioprotection of fresh and processed food for human and animal consumption, and could become an alternative to antibiotics used for diseases caused by E. coli and K. pneumoniae.

Cellular response of the bovine mammary gland after Weissella confusa infusion to control Streptococcus agalactiae / Resposta celular da glândula mamaria bovina após infusão com Weissella confusa para o controle de Streptococcus agalactiae / Respuesta celular de la glándula mamaria bovina después de la infusión con Weissella confusa para el control de Streptococcus agalactiae

Background: the use of lactic acid bacteria (LAB) as a potential therapeutic agent to control bovine mastitis was previously proposed. However, little is known about the cellular response of the bovine mammary gland in cattle infected with Streptococcus agalactiae and treated with LAB. Objective: to assess the cellular response by the mammary gland in lactating cows after infection with Streptococcus agalactiae followed by infusion with Weissella confusa as antibacterial treatment. Methods: healthy udder quarters of lactating cows were infected with S. agalactiae (10(7) cfu/mL). After 24 h of pathogen infusion, 50% of the quarters were infused with 109 cfu/mL of W. confusa (SW) and the remaining 50% were kept as control units (S). At days 1, 2, 3, 4, 5, 11, and 14 post-infusion of the pathogen, the clinical signs of mastitis and the degree of cellular response by the mammary gland were evaluated using the California mastitis test, somatic cell count, electrical conductivity, and differential leukocyte count in milk. Results: the SW quarters showed clinical inflammation of the mammary gland associated with a significant increase in somatic cell count, California mastitis test, electrical conductivity and high proportion of polymorphonuclear neutrophils. The results suggest that the infusion with W. confusa cells induced a higher cellular immune response in the bovine mammary gland than S. agalactiae alone. Conclusions: results indicate that W. confusa infusions for controlling S. agalactiae should not be adopted. However, the activation mechanism of somatic cells in the mammary gland needs to be elucidated.

Antecedentes: previamente se propuso el uso de bacterias ácido lácticas (LAB) como agentes terapéuticos potenciales para el control de mastitis bovina. Sin embargo, poco se ha investigado sobre la respuesta celular de la glándula mamaria bovina ante la aplicación de LAB en bovinos infectados con Streptococcus agalactiae. Objetivo: evaluar, en vacas lactantes, la respuesta celular de la glándula mamaria después de la infección con Streptococcus agalactiae y la infusión intrapezón con Weissella confusa como tratamiento. Métodos: cuartos sanos de ganado criollo Hartón del Valle en estado de lactancia, se infectaron con S. agalactiae (10(7)ufc/ mL). Transcurridas 24 horas post-infusión del patógeno, al 50% de los cuartos se les aplicó W. confusa a concentración de 10(9) ufc/mL (cuartos SW) y el 50% de los cuartos restantes se tomaron como unidades experimentales control (cuartos S). En los días 1, 2, 3, 4, 5, 11 y 14 pos-infusión del patógeno, se evaluaron signos clínicos de mastitis y el grado de respuesta celular de la glándula mamaria, a través de california mastitis test, recuento de células somáticas, conductividad eléctrica y diferencial de leucocitos en leche. Resultados: en los cuartos SW se observaron evidencias clínicas de inflamación de la glándula mamaria asociada con incremento significativo de recuento de células somáticas, California mastitis test, conductividad eléctrica, y altos porcentajes de neutrófilos polimorfonucleares. Los resultados sugieren que la infusión con células de W. confusa genera mayor respuesta celular en la glándula mamaria bovina que S. agalactiae. Conclusiones: los resultados indican que no puede utilizarse la infusión de células vivas de W. confusa como tratamiento para el control de S. agalactiae. Se debe investigar otro mecanismo de uso de la LAB para el tratamiento de mastitis bovina.

Antecedentes: previamente foi proposto o uso de bactérias ácido-lácticas (LAB), como agentes terapêuticos potenciais para o controle da mastite bovina. No entanto, pouca pesquisa tem sido feita sobre a resposta celular da glândula mamária de bovinos após aplicação de LAB em bovinos infectados com Streptococcus agalactiae. Objetivo: avaliar, em vacas em período de lactação, a resposta celular da glândula mamária após a infecção com Streptococcus agalactiae e a infusão dentro da teta de Weissella confusa como tratamento. Métodos: tetas saudáveis de gado nativo Harton del Valle em lactação foram infectados com S. agalactiae (10(7)ufc/mL). Ventiquatro horas após a infusão do agente patogénico, a 50% dos quartos foi administrada W. confusa em concentração de 10(9) ufc/mL (quartos SW) e 50% dos quartos foram usados como unidades experimentais de controle (quartos S). Nos dias 1, 2, 3, 4, 5, 11 e 14 após a infusão do agente patogénico, foram avaliados os sinais clínicos de mastite e o grau de resposta celular da glândula mamária através do Califórnia Mastite Teste, contagem de células somáticas, condutividade elétrica e diferencial de leucócitos do leite. Resultados: nos quartos SW observou-se evidência clínica de inflamação da glândula mamária associado ao aumento significativo na contagem de células somáticas, Califórnia mastite teste, condutividade eléctrica, e altas porcentagens de neutrófilos polimorfonucleares. Os resultados sugerem que a infusão de células de W. confusa gera maior resposta celular na glândula mamária bovina que o S. agalactiae. Conclusões: os resultados indicam que a infusão de células vivas de W. confusa como um tratamento para o controle de S. agalactiae não pode ser usado. Outros métodos de uso da LAB para o tratamento de mastite devem ser pesquisados.

Guava Psidium guajava seed flour and dry Aspergillus niger mycelium as nitrogen sources for the production of biomass and antimicrobial compounds produced by Weissella confusa

Background: The fermentation substrate efficiency of glucose supplemented with guava seed flour (GGSF) or glucose supplemented with dry Aspergillus niger mycelium (GANM) was evaluated during the production of biomass and antimicrobial compounds by the lactic acid bacteria Weissella confusa. Results: The fermentation substrate efficiency was measured by comparing the biomass formation, substrate consumption, substrate conversion, antimicrobial activity and product yield. The antimicrobial activity was measured against a commercial Staphylococcus aureus strain. The results were compared against fermentations performed in a commercial substrate (CS), the MRS (Man-Rogosa-Sharpe) substrate. The fermentations were performed discontinuously for 4 hrs at 100 rpm and 32ºC. The biomass production exhibited a statistically significant difference (P ≤ 0.05) between treatments. The biomass production was 13.98% higher in the CS than in the GGSF and GANM substrates; however, there were no statistically significant differences for the specific growth rate. Conclusions: The GGSF and GANM substrates favored an antimicrobial activity against Staphylococcus aureus during the second and third hours of fermentation (inhibition diameter was 6.11% and 4.72%, respectively). The GGSF, GANM and CS substrates did not present statistically significant differences for the production of antimicrobial substances against Staphylococcus aureus. Therefore, GGSF and GANM can be considered as viable and economical alternative nitrogen sources for the production of the antimicrobial compounds formed by Weissella confusa in submerged fermentations.

Effects of fermentation substrates and conservation methods on the viability and antimicrobial activity of weissella confusa and its metabolites

Lactic acid bacteria produce metabolites with antagonistic activity against other bacteria. However, growth conditions and conservation methods may reduce the viability and antimicrobial activity of lactic acid bacteria. This study evaluated the effects of fermentation substrate, lyophilization (freeze-drying) and refrigeration on the viability and antimicrobial activity of Weissella confusa strain and its metabolites against pathogens responsible for bovine mastitis. W. confusa strain was grown in MRS broth and milk supplemented with yeast extract and glucose (MYEG). The collected fractions were preserved by lyophilization or under refrigeration at 4ºC. Every seven days, the viability of W. confusa strain and the stability of its metabolites were evaluated against Staphylococcus aureus and Streptococcus agalactiae by disc diffusion assays. In both fermentation substrates, the combination of lyophilized strain and metabolites retained antimicrobial activity against the two pathogens for 42 days. Also, W. confusa strain retained adequate viability and antimicrobial activity when grown in MYEG and stored under refrigeration conditions. It was concluded that MYEG and refrigeration are acceptable low cost options to preserve the viability of W. confusa for its potential commercial use in the prevention and treatment of bovine mastitis.

Plan de saneamiento para una distribuidora de alimentos que atiende a niños y adultos mayores / A sanitation plan for a food distributor attending children and the elderly

Los niños y adultos mayores representan los consumidores más vulnerables a adquirir enfermedades transmitidas por alimentos, ETA, por lo que se hace más estricto disminuir los factores de riesgo que se generan en la elaboración de alimentos dirigidos para este grupo de población. En este reporte, con el fin de disminuir los factores de riesgo de ETA a una población de niños y adultos mayores, se diseñó y se implementó un plan de saneamiento, siguiendo los lineamientos de decreto 3075 de 1997 del Ministerio de Protección Social de Colombia, y se realizó un plan de capacitación dirigido al personal manipulador implicado en los procesos de recepción, almacenamiento, empaque y distribución de materias primas en una distribuidora de alimentos. El plan de saneamiento y la capacitación permitieron incrementar los porcentajes de cumplimiento en buenas prácticas de manufactura, BPM, del 40 al 70 por ciento, estos resultados son una base sólida para garantizar la inocuidad de los alimentos y la disminución del riesgo de adquirir ETA en la población objeto de estudio.

The responsibility for providing healthy food involves all members of the production chain from input supplier to the distributor and consumer of food. Children and older adults represent the most vulnerable consumers for acquiring food-borne illness (FBI), meaning that the risk factors produced in food-processing targeted for this population group must be reduced. A clean-up plan was thus designed and implemented following the guideline laid down in decree 3075/1997 to reduce FBI risk factors in a population of children and older adults. A training plan was also conducted for handling staff involved in receiving, storing, packaging and distributing raw materials in a food distributor. The clean-up plan and training led to a 40 percent to 70 percent increase in compliance with best manufacturing practices (BPM). These results represent a solid basis for ensuring food safety and reducing the risk of acquiring FBI in the study population. This article also provides an outline for easily acquiring the necessary methodology for implementing a clean-up plan in a food industry.

Efecto de la agitación sobre la deshidratación osmótica de pitahaya amarilla (selenicereus megalanthus s.) Empleando soluciones de sacarosa / Effect of stirring on osmotic dehydration of yellow pitahaya (selenicereus megalanthus s.) Using sucrose solutions / Efeito da agitação sobre a desidratação osmótica de pitaya amarela (selenicereus megalanthus s.) Empregando soluções de sacarose

Se estudió el efecto de la agitación (180, 220, y 240rpm) sobre la pérdida de agua y la ganancia de azúcar en rodajas de pitahaya deshidratas osmóticamente, empleando soluciones osmóticas de sacarosa con dos niveles de concentración, 45 y 55°Brix. Adicionalmente, se determinó la porosidad de la pitahaya en estado fresco y deshidratado osmóticamente, y se relacionó con los niveles de agitación. Los resultados mostraron que los niveles de agitación inciden significativamente sobre la pérdida de agua, presentando mayor variación relativa para los tratamientos a 45ºBrix. La ganancia de azúcar no presentó diferencias significativas por efecto de los niveles de agitación. Lo anterior se explica por la baja porosidad de la pitahaya en estado fresco (2,78 ±0,35%), que dificulta la entrada de la molécula de sacarosa en la fruta. Los resultados sugieren que la deshidratación osmótica se perfila como una técnica de pretratamiento apropiada para la pitahaya amarilla debido a la baja ganancia de sólidos durante el proceso.

The effect of the stirring (180, 220, y 240rpm) on water loss and sugar gain in the process of osmotic dehydration of pitahaya slices was studied, using osmotic solutions of sucrose with two concentration levels, 45 and 55°Brix. Additionally, the porosity of the pitahaya in fresh and osmotically dehydrated states was determined and related to the stirring speed. The results showed that stirring level has a significant effect on water loss, with a greater relative variation for the treatments at 45°Brix. Sugar gain did not show significant differences as an effect of agitation speed. This is explained by the low porosity of the pitahaya in fresh state (2.78 ±0.35%), which hinders the entry of the sucrose molecules into the fruit. The results suggest that osmotic dehydration is emerging as an appropriate pretreatment technique for the yellow pitahaya due to the low gain in solids during the process.

Estudou-se o efeito da agitação (180, 220, e 240rpm) sobre a perda de água e o ganho de açúcar en rodelas de pitaya desidratas osmoticamente, empregando soluções osmóticas de sacarose com dois níveis de concentração, 45 e 55°Brix. Adicionalmente, se determinou a porosidade da pitaya em estado fresco e desidratado osmoticamente, e se relacionou com os níveis de agitação. Os resultados mostraram que os níveis de agitação incidem significativamente sobre a perda de água, apresentando maior variação relativa para os tratamentos a 45ºBrix. O ganho de açúcar não apresentou diferenças significativas por efeito dos níveis de agitação. O anterior se explica pela baixa porosidade da pitaya em estado fresco (2,78 ±0,35%), que dificulta a entrada da molécula de sacarose na fruta. Os resultados sugerem que a desidratação osmótica se perfila como uma técnica de pre-tratamento apropriada para a pitaya amarela devido ao baixo ganho de sólidos durante o processo.

Aplicación de eddopeptidasa alcalina en carnaza bovina para mejorar la calidad de la gelatina / Aplication of allkaline endopeptidase in bovine hide to improve the quality of the gelatine / Aplicaço da endoopeptidse alcalina na pele bovina para melhorar a quallidade da gelatina

El precio de la gelatina en el mercado internacional está determinado por sus propiedades físico-químicas que dependen a su vez de la materia prima, de la forma de extracción del colágeno y de su método de concentración. En este estudio, utilizando procesos de producción en planta piloto de gelatina tipo B, se evaluó el efecto de la aplicación de una endopeptidasa alcalina en el pretratamiento de tres tipos de carnaza bovina sobre la calidad final de la gelatina medida como bloom , viscosidad y claridad. Los resultados se compararon con procesos en los cuales se utilizaron las mismas materias primas sin pretratamiento enzimático. Los análisis estadísticos mostraron diferencias significativas entre los tratamientos. Los mejores resultados de bloom , viscosidad y claridad se presentaron utilizando la enzima en el pretratamiento de la carnaza entera; en trece horas de proceso se obtuvo el 61,5% de la gelatina con bloom alto superior a 300 g , el 51,3% con viscosidades altas mayores de 42 mp y el 82,1% con claridades altas menores de 39 unidades nefelométricas de turbidez. La carnaza entera sin pretratamiento enzimático presentó el 41% de valores altos de bloom , el 7,7% de viscosidades altas y el 76,9% de claridades altas .

The international market price of gelatine is determined by its physical-chemical properties, that depend on the raw material, the collagen extraction method and the concentration method. In this work, using class B gelatine production processes in pilot plant, the effect of application of alkaline endopeptidase was evaluated in the pre-treatment of three types of bovine hide on the gelatine final quality as measured by bloom, viscosity and clarity. The results were compared with processes in which the same raw materials were used without enzymatic pre-treatment. The statistical analysis showed significant differences among the treatments. The best bloom, viscosity and clarity results were presented using enzymatic pre- treatment in the whole hide, obtained in thirteen hours of process 61.5% of the gelatine with bloom higher than 300g, 51.3% with viscosities values higher than 42 mp and 82 ,1 % with high clarities value, with values lower than 39 nephelometric turbidity units. The whole hide without enzymatic pre-treatment showed 41% of high values of bloom, 7.7% of high viscosities and 76.9% of high clarities .

O preço da gelatina no mercado internacional é determinado pelas suas propriedades físico-químicas as quais dependem da matéria-prima, da forma de extração do colágeno bovino e do método de concentração. Neste estudo, utilizando processos de produção em planta piloto de gelatina tipo B, foi avaliado o efeito da aplicação da protease alcalina no pré-tratamento de três tipos de pele bovina sobre a qualidade final da gelatina determinada como bloom , viscosidade e transparência. Os resultados foram comparados com processos nos quais se utilizaram as mesmas matérias-primas sem pré-tratamento enzimático. As análises estatísticas mostraram diferenças significativas entre os tratamentos. Os melhores resultados de bloom , viscosidade e transparência foram obtidos utilizando protease alcalina no pré-tratamento da pele inteira, se obtendo em treze horas do processo o 61,5% de gelatina com bloom alto superior a 300 g , o 51,3% com viscosidades altas maiores a 42 mp e o 82,1% com transparências altas menores a 39 unidades nefelométricas de turbidez . A pele inteira sem pré-tratamento enzimático apresentou o 41% dos valores altos de bloom , o 7,7% de viscosidades altas e o 76,9% de transparências altas.

Lactic acid fermentative production using waste from the harvest of green sugar cane as a substrate

Para la producción fermentativa de ácido láctico se evaluaron como sustrato residuos de cosecha de caña de azúcar (variedad CC85-92). Las fermentaciones se realizaron a 32ºC y pH 6,0, utilizando jugos obtenidos de hojas y cogollos (JTL), y Lactococcus lactis subs. lactis aislado de caña de azúcar de la misma variedad. En las fermentaciones se midieron la concentración de ácido láctico (LA), la conversión de sustrato (SC), la concentración de biomasa, la velocidad de formación de producto (rp) y el rendimiento (Yp/s), y los resultaron se compararon con fermentaciones que utilizaron la misma cepa y medio de cultivo comercial MRS adicionado de glucosa hasta 60g.l-¹. Utilizando JTL se pueden obtener concentraciones de ácido láctico por encima de 28,5g.l-¹ y rendimientos de 0,85g. g-¹ en 48 horas de fermentación. Los sustratos JTL y MRS mostraron diferencias estadísticamente significativas en Yp/s, SC y concentración de biomasa, y diferencias estadísticamente no significativas en LA y rp. Los resultados sugieren que los residuos de cosecha de caña de azúcar pueden ser utilizados como materia prima barata para la producción fermentativa de ácido láctico.

Lactic acid production by a strain of Lactococcus lactis subs lactis isolated from sugar cane plants

A Lactococcus lactis subs lactis strain was selected from 20 lactic acid strains isolated from the leaves of sugar cane plants, variety CC 85-92. The effects of substrate concentration and pH control on lactic acid (LA) production, glucose conversion (GC) and yield (Yp/s) were investigated using this strain. In batch fermentation at 32ºC, with 60 gl-1 of glucose and a pH of 6.0, concentrations of up to 35 gl-1 of lactic acid were obtained. Maximum production and glucose conversion was achieved at low glucose concentrations. The strain shows great potential for lactic acid production from glucose, even without using pH control during fermentation (13.7 gl-1).

Producción de ácido láctico por una mezcla de Lactococcus lactis y Streptococcus salivarius en fermentaciones en discontinuo / Lactic acid production from a mixture of cultures of Lactococcus lactis and Streptococcus salivarius using batch fermentation

Se estudió la producción de ácido láctico (AL), la conversión de sustrato (CG), y el rendimiento (Y p/s) de Lactococcus lactis, Streptococcus salivarius y una mezcla 1:1 de ambas cepas en sustrato glucosado. Lactococcus lactis se seleccionó de 20 cepas homofermentativas aisladas de cultivos de caña de azúcar variedad CC85-92 y Streptococcus salivarius se aisló de un fermento láctico comercial. En fermentaciones llevadas a cabo con lamezcla microbiana, a 32 °C con 60 gL-1 de glucosa y pH 6,0 se obtuvo un máximo de 47,63 gL-1 de ácido láctico, conversión de glucosa de 95,4% y rendimiento en producto de 0,83 gg-1.

Production of lactic acid (LA), yield (Y p/s) and substrate conversion (SC) from Lactococcus lactis, Streptococcus salivarius and their mixtures were tested. Lactococcus lactis was selected from 20 homofermentative strains isolated from a sugar cane crop (variety CC85-92) and Streptococcus salivarius was isolated from a commercial lactic ferment. Batch fermentation experiments at 32 C with a glucose concentration of 60 gL-1 and a pH of 6,0 were carried out. A maximum of 47,63 gL-1 of lactic acid concentration, 95,4% of substrate conversion and 83 gg-1were obtained from the mixture of strains after a fermentation of 48 h.