Efecto bioconservante del propóleo y su aplicación en la conservación de matrices cárnicas / Bioconservative Effect of Propolis and its Application in the Conservation of Meat Matrices

Resumen: Antecedentes: los conservantes de origen sintético, como nitratos y nitritos, empleados en la industria alimentaria para la conservación de matrices cárnicas, han reportado efectos desfavorables a largo plazo en la salud de los consumidores recurrentes. Objetivo: conocer las características fisicoquímicas y antimicrobianas del propóleo como potencial bioconservante en matrices cárnicas de alto consumo. Materiales y métodos: se desarrolló una revisión bibliográfica de literatura acorde a la pregunta problema planteada por el grupo de investigación, y se llevó a cabo una búsqueda en las bases de datos Scopus, NCBI, SciELO, ScienceDirect y Google Scholar de artículos de revisión, artículos científicos, libros y trabajos de grado. Resultados: el propóleo es un compuesto natural con una variedad amplia de elementos útiles para la conservación de matrices cárnicas, por sus propiedades antimicrobianas y antioxidantes. Conclusiones: el propóleo presenta propiedades antimicrobianas y antioxidantes útiles en el campo de la industria alimentaria, por lo que se considera una de las alternativas más viables para la conservación de productos cárnicos y la disminución del uso de conservantes sintéticos en producción cárnica. No obstante, es fundamental el desarrollo de más investigaciones que permitan evaluar el comportamiento de los compuestos activos del propóleo en las diversas matrices cárnicas

Abstract: Background: Preservatives of synthetic origin, such as nitrates and nitrites, used in the food industry for the preservation of meat matrices, have reported long-term unfavorable effects on the health of recurrent consumers. Objective: To know the physicochemical and antimicrobial characteristics of propolis as a potential biopreservative in high consumption meat matrices. Materials and Methods: A bibliographic review of literature was developed according to the problem question posed by the research group, carrying out a search in the Scopus, NCBI, SciELO, ScienceDirect and Google Scholar databases of review articles, scientific articles, books and works degree. Results: Propolis is a natural compound with a wide variety of useful elements for the conservation of meat matrices, due to its antimicrobial and antioxidant properties. Conclusions: Propolis has useful antimicrobial and antioxidant properties in the field of the food industry, being considered one of the most viable alternatives for the preservation of meat products and the reduction of the use of synthetic preservatives in meat production. However, it is essential to develop more research to evaluate the behavior of the active compounds of propolis in the various meat matrices

Concentrações de nitrito e nitrato em salsichas / Nitrite and nitrate levels in sausages / Concentraciones de nitrito y nitrato en salchichas

OBJETIVO: Determinar as concentrações de nitrito e nitrato, potencial hidrogeniônico (pH) e atividade de água (Aa) em salsichas comercializadas em uma região do sul do Brasil, e comparar essas concentrações entre as diferentes marcas. MÉTODOS: Estudo experimental, transversal, quantitativo, realizado com 72 amostras de salsicha coletadas em dois municípios da Região do Vale do Taquari/RS, entre junho e agosto de 2015. Avaliaram-se três amostras de lotes diferentes, por meio das variáveis de nitrito, nitrato, pH e atividade de água, em triplicata, de cada uma das oito marcas de salsichas fiscalizadas pelo Serviço de Inspeção Federal. Dados submetidos aos testes ANOVA e Qui-quadrado, com p<0,05. RESULTADOS: A totalidade das amostras apresentou-se dentro dos padrões para pH e Aa (6,33 ± 0,32 e 0,91 ± 0,01, respectivamente), enquanto 40,3% (29) e 50,0% (36) apresentaram níveis de nitrito e nitrato, respectivamente, significativamente acima do estabelecido pela legislação (p<0,05). A média de nitrito das amostras restantes apresentou-se significativamente inferior (p=0,001), e a média de nitrato, significativamente superior (p=0,009) ao valor estabelecido pela legislação. CONCLUSÃO: A totalidade das amostras estava adequada em relação aos níveis de pH e Aa. Do total das oito marcas avaliadas, três se encontravam em condições satisfatórias referente à adição do nitrato e nitrito. A média de nitrito e Aa foi significativamente inferior, e as médias do nitrato e pH, significativamente superior, enquanto os níveis de nitrato e nitrito apresentaram médias superiores aos valores estabelecidos legislação, em cinco marcas analisadas

OBJECTIVE: To determine nitrite and nitrate levels, hydrogen potential (pH), and water activity (aw) in sausages marketed in Southern Brazil, and compare the levels among different brands. METHODS: Quantitative experimental cross-sectional study conducted with 72 sausage samples collected in two municipalities in the Região do Vale do Taquari, Rio Grande do Sul,,between June and August 2015. Three samples from different batches of each eight distinct sausage brands which were supervised by the Federal Inspection Service were analyzed in triplicate according to their nitrite and nitrate levels, pH and water activity. Data underwent ANOVA and Chi-squared tests with p<0.05. RESULTS: Samples met the recommended standards for pH and water activity (6.33 ± 0.32 and 0.91 ± 0.01, respectively), while 40.3% (29) and 50.0% (36) of the samples presented nitrite and nitrate levels, respectively, significantly above what is recommended by the legislation (p<0.05). The mean nitrite levels of the remaining samples were significantly lower (p=0.001), and mean nitrate levels were significantly higher (p=0.009) than the value established by legislation. CONCLUSION: The samples met the recommended levels of pH and water activity. Of eight brands assessed, three presented satisfactory levels of nitrate and nitrite. The mean levels of nitrite and water activity were significantly lower and the mean levels of nitrate and pH were significantly higher than the recommendations. Additionally, mean nitrate and nitrite levels of five brands were significantly higher than what is recommended by the legislation

OBJETIVO: Determinar las concentraciones de nitrito y nitrato, del potencial de hidrógeno (pH) y de la actividad del agua (Aa) de salchichas del comercio de una región del sur de Brasil y compararlas entre las distintas marcas comerciales. MÉTODOS: Estudio experimental, transversal y cuantitativo realizado con 72 muestras de salchichas recogidas en dos municipios de la Región del Vale del Taquari/RS entre junio y agosto de 2015. Se evaluaron tres veces tres muestras de lotes distintos a través de las variables de nitrito, nitrato, pH y actividad del agua de cada una de las ocho marcas de salchichas fiscalizadas por el Servicio de Inspección Federal. Los datos fueron sometidos a las pruebas ANOVA y Chicuadrado para p<0,05. RESULTADOS: La totalidad de las muestras se presentó dentro de los patrones para el pH y la Aa (6,33 ± 0,32 e 0,91 ± 0,01, respectivamente) mientras el 40,3% (29) y el 50,0% (36) presentaron niveles de nitrito y nitrato, respectivamente, significativamente por encima de la legislación (p<0,05). La media de nitrito de las muestras restantes se presentó significativamente inferior (p=0,001) y la media de nitrato, significativamente superior (p=0,009) de la legislación. CONCLUSIÓN: La totalidad de las muestras estaba adecuada respecto a los niveles de pH y Aa. Del total de las ocho marcas evaluadas, tres se encontraban en condiciones satisfactorias de adicción del nitrato y nitrito. La media de nitrito y Aa fue significativamente inferior y las medias de nitrato y pH significativamente superior mientras los niveles de nitrato y nitrito presentaron medias superiores de la legislación em cinco marcas analizadas

Influence of physical and chemical factors on the survival of Pichia isolated from Glucose syrup / Influencia de factores fósicos y químicos sobre la sobrevivencia de Pichia aislada de jarabe de glucosa

Yeasts belonging to the genus Pichia were isolated from glucose syrup samples. Yeasts were identified as P. anomala ( it is now Wickerhamomyces anomala) and P. guilliermondii. These strains did not metabolize the nutritive preservatives, potassium sorbate or sodium benzoate when these were used as the single carbon source. P. anomala grew in culture media containing up to 1200 mg/L of both preservatives. Critical temperature and time of exposure for its inactivation were 60 °C and 3 min, respectively. P. guilliermondii grew in media containing up to 1400 mg/L of both preservatives. Critical temperature and time for inactivation of this Pichia were 80 °C and 2 min. This strain was able to grow in a wide range of temperatures (5 to 30 °C), pH (2.5 to 5.5) and glucose concentrations (200 to 800 g/L). At 5 °C and 800 g/L glucose (osmotic pressure, 0.110 atm), P.guilliermndii grew poorly, with no cell death because of its ability to sporulate. We determined that P. guilliermondii is a potentially contaminating yeast able to develop in a variety of foods, especially those with low pH or with high sugar concentrations (glucose above 400g/L) such as refreshments, juices, syrups and confected fruits and it is resistant to both food preservatives and low temperatures (5°C).

De muestras de jarabe de glucosa fueron aisladas levaduras que pertenecen al género Pichia. Estas fueron identificadas como P.anomala (actualmente Wickerhamomyces anomala) y P. guilliermondii, ambas cepas no metabolizan los conservantes alimenticios, sorbato de potasio o benzoato de sodio, al ser usados como única fuente de carbono. P. anomala desarrolló en medios de cultivo que contenían hasta 1200 mg/L de ambos conservantes. La temperatura y el tiempo crítico de exposición para su inactivación fueron 60 °C y 3 min, respectivamente. P.guilliermondii desarrolló en medios que contienen hasta 1400 mg/l de ambos conservantes. La tº y el tiempo crítico de inactivación fueron 80 °C y 2 min. Esta cepa fue capaz de desarrollar en un amplio rango de temperaturas (5 a 30 °C), pH (2,5 a 5,5) y concentraciones de glucosa (200 a 800 g/L). A 5 °C y glucosa 800 g/L (presión osmótica, 0,110 atm), P. guilliermondii desarrolló pobremente sin que se produzca la muerte celular debido a su capacidad de esporular. Se determinó que P. guilliermondii, es una levadura potencialmente contaminante que puede desarrollarse en una variedad de alimentos, especialmente aquellos con bajo pH o altas concentraciones de azúcar (glucosa, > 400 g/L) como en gaseosas, jugos, jarabes y frutas confitadas, y es resistente a ambos conservantes y bajas tº (5°C).

Effect of Some Food Preservatives on the Lipolytic Activity of Beef Luncheon Fungi

Beef luncheon meat is one of the most popular meals in several countries in the world including Egypt. Thirty one fungal species and 3 species varieties were recovered from 30 samples of beef luncheon meat collected from different supermarkets in Qena. Alternaria, Aspergillus, Emericella, Mucor, Mycosphaerella, Penicillium and Rhizopus were the most common genera on the two types of media. From the above genera, the most prevalent species were Alternaria alternate, Aspergillus flavus, A. fumigatus, A. niger, A. terreus, Emericella nidulans, Mucor racemosus, Mycosphaerella tassiana, Penicillium chrysogenum and Rhizopus stolonifer. Screening of fungi for their abilities to produce lipase enzyme showed that, ten isolates represented 32.26% of total isolates appeared high lipase production, while sixteen isolates (51.61%) were moderate and 5 isolates (16.13%) were low producers. Aspergillus niger, Fusarium oxysporum and Nectria haematococca produced the highest amount of lipase enzyme, so these fungi were used in further studies. The incorporation of five food preservatives (Disodium phosphate, sodium benzoate, citric acid, potassium sorbate and sodium citrate) individually in the culture medium of lipase production exhibited an inhibitive effect on the mycelial growth and enzyme production by Aspergillus niger, Fusarium oxysporum and Nectria haematococca.