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1.
Braz. arch. biol. technol ; 61: e18170824, 2018. graf
Artigo em Inglês | LILACS | ID: biblio-974098

RESUMO

ABSTRACT Edible films are an alternative to synthetic materials used for packaging foods. The aim of this study was to develop and characterize films made from cassava starch, freeze-dried acai and glycerol. The films were characterized for thickness, water vapor permeability, water solubility, anthocyanins, antioxidant capacity and mechanical properties. The results indicated a rich edible film in anthocyanins with considerable antioxidant capacity (150.70 micromol Trolox), which can extend the commercial validity of the packaged food and meets the growing demand for biodegradable packaging that tends to reduce the environmental impact. The addition results in a significant effect on the polymer matrix reducing the water solubility and water activity. The elongation test at rupture reported to be 17.738%, indicating that addition of pulp increased film flexibility.

2.
Vitae (Medellín) ; 22(2): 111-120, 2015. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-987857

RESUMO

Background: One of the aims of food packaging is to protect the product from environmental factors that can cause a reduction in quality. Surface growth of microorganism is one of the leading causes of food spoilage. One option is to use antimicrobial packaging to provide an increased margin of safety and quality. Objectives: The aim of this study was evaluate the effect of active packaging with eugenol on growth of Pseudomonas and aerobic mesophilic bacteria in fresh chicken pieces. Methods: Three batches of low-density polyethylene (LDPE) film, containing 0, 9.0 and 7.7, mg g-1 eugenol (control, AAF1 and AAF2, respectively), were extruded in a pilot-plant scale blown-extrusion machine. The films with eugenol lost 42.7% and 36.8% (AAF1 and AAF2, respectively) of eugenol during processing and absorbed UV-visible light at 300-261 nm. The kinetics of eugenol release from the AAF1 into the air at 5°C and 25ºC displayed Fick's behavior, and a diffusion coefficient of 10-8 cm2 s-1 was calculated. Results: Eugenol showed antimicrobial activity on in vitro, using paper discs with 1.74, 0.87 and 0.36 mg eugenol on 108 CFU mL-1 of Pseudomonas fluorescens in Muller-Hinton agar. Chicken thighs were wrapped in the AAF2 film, and the effects on the growth of Pseudomonas and aerobic mesophilic bacteria (AMB) were evaluated after storage for 5 d at 5°C. The AAF2 showed a moderately antimicrobial effect in reducing the growth of Pseudomonas (1.1 x 106 CFU g-1) relative to growth in the control film (6.0 x 106 CFU g-1) (P < 0.05). The film with eugenol was effective in reducing the growth of AMB (9.0 x 105 CFU g-1) relative to growth in the control film (1.7 x 106 CFU g-1) (P < 0.05). Conclusions: Despite the high losses of eugenol during the extrusion of the films, they showed an antimicrobial effect during contact with fresh chicken under commercial conditions. This study shows the potential use of eugenol for application in LDPE antimicrobial packaging film.


Antecedentes: Uno de los principales objetivos del envasado de alimentos es protegerlo de factores que puedan afectar y causar una reducción en la calidad. El desarrollo de microorganismos en la superficie es uno de las causas principales del deterioro de los alimentos. Una opción es el empleo de envases con propiedades antimicrobianas. Objetivos: El objetivo del presente estudio fue evaluar el efecto de un envase antimicrobiano conteniendo eugenol en el desarrollo de Pseudomonas y bacterias mesofílicas aerobias (BMA) en piezas de pollo. Métodos: Tres lotes de película de polietileno de baja densidad (PEBD) conteniendo 0, 9.0 y 7.7 mg g-1 de eugenol (control, AAF1, AAF2, respectivamente) fueron obtenidas por extrusión-soplo utilizando un extrusor a nivel planta piloto. Se calculó la cinética de liberación del eugenol de la AAF1 hacia el aire a 5°C y 25°C. Se evaluó la capacidad antimicrobiana in vitro del eugenol sobre 108 UFC mL-1 de Pseudomona fluorescens utilizando discos de papel conteniendo 1.74, 0.87 y 0.36 mg de eugenol en agar Muller-Hinton. Las piezas de pollo fueron envueltas en la película AAF2 y almacenadas a 5°C evaluando a los 5 días el efecto de la película en el desarrollo de Pseudomonas y en BMA. Resultados: El eugenol mostró actividad antimicrobiana inhibiendo el crecimiento de P. fluorescens. Las películas conteniendo eugenol perdieron durante el proceso de extrusión 42.7% y 36.8% (AAF1 y AAF2 respectivamente) del total añadido mostrando un comportamiento fickiano con un coeficiente de difusión de 10-8 cm2 s-1. Las AAF2 mostraron un efecto moderado en la reducción del desarrollo de Pseudomonas (1.1 x 106 CFU g-1) comparadas con el control (6.0 x 106 CFU g-1) (P < 0.05). Las películas con eugenol (AAF2) fueron efectivas al reducir el desarrollo de las BMA (9.0 x 105 CFU g-1) comparadas con la película control (1.7 x 106 CFU g-1) (P < 0.05). Conclusiones: A pesar de las pérdidas del eugenol durante el proceso de extrusión para la obtención de las películas, estas mostraron un efecto antimicrobiano sobre las piezas de pollo. Por lo tanto, este estudio muestra el uso potencial del eugenol para la aplicación en envases antimicrobianos elaborados a base de PEBD.


Assuntos
Humanos , Anti-Infecciosos , Pseudomonas , Bactérias Aeróbias , Eugenol , Galinhas
3.
Braz. j. microbiol ; 44(4): 1181-1188, Oct.-Dec. 2013. ilus, tab
Artigo em Inglês | LILACS | ID: lil-705259

RESUMO

This study was developed in order to evaluate two alternatives for the control of Listeria monocytogenes in raw bovine meat pieces, both based on the use of Thymus vulgaris and Rosmarinus officinalis essential oils (EOs). The antilisterial activity of different concentrations of the EOs was tested in vitro using agar dilution and disk volatilization techniques. In addition, L. monocytogenes was inoculated in meat pieces, which were submerged in edible gelatin coatings containing 2% (v/v) EOs or submitted to the vapor of EOs (0.74 μL.cm-3). L. monocytogenes was quantified after one, 48 and 96 hours of storage (7 °C). In the in vitro tests, the EO of T. vulgaris presented higher activity. The two options used (edible gelatin coating and vapor activity), in spite of exercising effects with differentiated behaviors, presented antibacterial activity against L. monocytogenes inoculated in raw bovine meat (p < 0.05). Greatest antibacterial activity were obtained in the experiment that used edible coatings containing EOs, at 48 hours of storage reductions in bacterial counts between 1.09 and 1.25 Log CFU.g-1 were obtained. In the vapor effect experiment, the EO of T. vulgaris caused the highest reduction in the population of bacteria inoculated in raw bovine meat (p < 0.05), 0.40 Log CFU.g-1 at 96 hours of storage. This study supplied important information regarding new and promising natural alternatives, based on the concept of active packaging, for the control of L. monocytogenes in the meat industry.


Assuntos
Animais , Bovinos , Antibacterianos/farmacologia , Conservantes de Alimentos/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Carne/microbiologia , Óleos Voláteis/farmacologia , Thymus (Planta)/química , Antibacterianos/isolamento & purificação , Carga Bacteriana , Conservantes de Alimentos/isolamento & purificação , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação , Rosmarinus/química , Temperatura
4.
Ciênc. rural ; 43(3): 544-550, mar. 2013. ilus, tab
Artigo em Português | LILACS | ID: lil-668016

RESUMO

O objetivo do trabalho foi desenvolver e caracterizar uma embalagem biodegradável, utilizando como matriz polimérica a quitosana, plastificada com glicerol, bem como avaliar o efeito da adição de um aditivo antioxidante natural (urucum) nas embalagens na proteção antioxidante. As embalagens foram preparadas por casting contendo 1,5% de quitosana, 0,15% de glicerol e 0,25 a 1,0% de urucum. O azeite de dendê embalado com os filmes contendo o aditivo foi monitorado aos 0, 7, 15, 30 e 45 dias de armazenamento sob condições de oxidação acelerada (63%UR/30°C). O azeite de dendê embalado no filme que continha o maior percentual de urucum (1,0%) foi o que menos oxidou ao longo do período estudado. Constatou-se que, à medida que aumentam as perdas de Fenóis Totais nas formulações dos filmes, ocorre uma redução nos aumentos do Índice de Peróxidos do produto embalado, demonstrando assim que, ao invés do produto, os compostos da embalagem é quem estão sofrendo oxidação.


The objective was to develop and characterize a biodegradable packaging using chitosan as polymeric matrix, plasticized with glycerol, as well as evaluate the effect of adding a natural antioxidant additives (annatto) in antioxidant protection in packaging. The cans were prepared by casting containing 1.5% of chitosan, 0.15% glycerol and 0.25 to 1.0% of coloring. Palm oil packed with the films containing the additive was monitored at 0, 7, 15, 30 and 45 days of storage under accelerated oxidation conditions (63% UR/30°C). Palm oil packed in the film that contained the highest percentage of annatto (1.0%) was the least oxidized during the study period. It was found that, as they increase the losses of phenolic compounds in the formulations of the films, there is a reduction in the peroxide increases the packaged product, thus demonstrating that instead of the product, the compounds of the package's who are suffering oxidation.

5.
Braz. j. microbiol ; 43(4): 1419-1427, Oct.-Dec. 2012. tab
Artigo em Inglês | LILACS | ID: lil-665828

RESUMO

Antimicrobial active packaging delays or inhibits microorganism growth in packed products, and it can be used in a variety of food systems. The objective of the present research was to develop packaging incorporated with natural antimicrobial agents (active film). The effects of the active film on the spoilage, pathogenic microorganism counts, pH and color of the refrigerated chicken breast cuts were analyzed. Cellulose acetate-based active films incorporating two concentrations (20% and 50%, v/w) of rosemary (Rosmarinus officinalis L.) essential oil were manufactured and placed in contact with the chicken breast cuts for six days. An analysis of variance and mean comparison tests (Tukey's test, p<0.05) were performed on the results. The films that contained 20% essential oil and were intercalated with chicken breast samples did not demonstrate significant effects on the control of psychrotrophic or total coliform microorganisms during the storage period; however, the films incorporated with 50% essential oil demonstrated efficacy toward the control of coliforms during the storage of the samples (6 days, 2 ± 2ºC). The pH was related to the psychrotrophic microorganism count and was not influenced by the treatment. The color was not influenced by the time of storage or the treatment. The results demonstrate that active films incorporating 50% rosemary essential oil are effective at controlling certain microorganisms in chicken breast cuts.


Assuntos
Animais , Alimentos Congelados/análise , Antibacterianos/análise , Análise de Alimentos , Embalagem de Alimentos , Técnicas In Vitro , Produtos Avícolas/análise , Rosmarinus/análise , Contaminação de Alimentos , Microbiologia de Alimentos , Amostras de Alimentos , Métodos , Aves Domésticas
6.
Ciênc. rural ; 42(11): 2085-2091, nov. 2012. ilus, tab
Artigo em Português | LILACS | ID: lil-654325

RESUMO

O objetivo do trabalho foi desenvolver uma embalagem biodegradável utilizando como matriz polimérica o amido de mandioca plastificada com glicerol e reforçada com a incorporação de nanocelulose da fibra de coco, bem como, avaliar o efeito da adição de um aditivo natural (erva-mate) nas formulações de nanobiocompósitos com ação antioxidante. Os nanocristais de celulose (L/D=39) foram obtidos por hidrólise ácida com H2SO4 a 65%. Os filmes foram preparados por casting contendo 4,5 e 6,0% de amido, 0,5 e 1,5% de glicerol, 0,3% de nanocelulose e 20% de extrato de erva-mate. O armazenamento do azeite de dendê embalado com os filmes contendo o aditivo foi monitorado por 40 dias sob condições de oxidação acelerada (63%UR/30°C). Constatou-se que, à medida que aumentam as perdas de Polifenóis Totais nos filmes, ocorre um menor aumento do Índice de Peróxidos do produto embalado, demonstrando, assim, que, ao invés do produto, os compostos da embalagem é quem estão sofrendo oxidação. A incorporação de extrato de erva-mate não alterou as propriedades mecânicas e de barreira desses filmes.


The objective was to develop biodegradable packaging using a polymer matrix as the cassava starch plasticized with glycerol and reinforced with the incorporation of nanocelulose of coconut fiber, as well as to evaluate the effect of the addition of an additive nature (yerba mate) in nanobiocompósitos formulations with antioxidant action. The nanocrystal cellulose (L/D=39) were obtained by acid hydrolysis with 65% H2SO4. The films were prepared by casting containing 4.5 and 6.0% starch, 0.5 and 1.5% glycerol, 0.3% nanocelulose and 20% extract of yerba mate. The palm oil storage packed with films containing the additive was monitored for 40 days under conditions of accelerated oxidation (63%UR/30°C). It was found that as the losses increase polyphenol films, there is a smaller increase of the peroxide value of the packaged product, thus demonstrating that instead of the product, the compounds of the package's who are suffering oxidation. The incorporation of yerba mate extract did not alter the mechanical and barrier properties of these films.

7.
Ciênc. rural ; 41(3): 537-543, mar. 2011. ilus, tab
Artigo em Português | LILACS | ID: lil-579658

RESUMO

A indústria de alimentos, buscando atender à crescente demanda dos consumidores, vem desenvolvendo embalagens ativas para proporcionar qualidade e segurança aos produtos acondicionados. Este trabalho objetivou desenvolver e avaliar a aplicação de filmes ativos aromatizados em contato com a massa de pastel. Os filmes foram preparados pelo método casting, adicionados de ácido sórbico e aroma de pizza e avaliados in vitro frente ao microrganismo Penicillium sp. Também foram estudadas suas propriedades mecânicas, migração de ácido sórbico, avaliação sensorial do produto e análise microbiológica in vivo. Os filmes ativos apresentaram atividade antimicrobiana tanto in vitro como no alimento. A caracterização mecânica mostrou que os filmes ativos aromatizados apresentaram valores de carga máxima na ruptura, inferiores ao filme controle e, durante a migração, a adição de aroma contribuiu para uma maior liberação do ácido sórbico. Além disso, as massas de pastel em contato com os filmes ativos aromatizados apresentaram melhores resultados sensoriais.


The food industry, trying to meet growing consumer demand, is developing active packaging to provide quality and safety for packed food. This research aimed to develop and evaluate the implementation of active flavored films in contact with pastry dough. The active films were evaluated for in vitro antimicrobial activity against Penicillium sp. The mechanical properties of the films, the sorbic acid migration, sensory and in vivo microbiological analyses were also tested. The active films showed better results for in vitro and in vivo microbiological analyses when compared with the film with the sorbic acid incorporated directly on the pastry dough. The incorporation of sorbic acid and flavor affected the mechanical properties of the active films compared to the control film. The flavor addition provided a larger migration of sorbic acid from the film to the pastry dough. Besides the pastry dough packed in the active films showed better sensory results.

8.
Ciênc. agrotec., (Impr.) ; 32(5): 1538-1542, set.-out. 2008. tab
Artigo em Português | LILACS | ID: lil-497003

RESUMO

O uso de absorvedores de oxigênio em embalagens de produtos alimentícios acondicionados tem apresentado uma demanda crescente. Assim, o conhecimento da eficiência desses absorvedores em diferentes condições de umidade relativa e temperaturas definidas, são de fundamental importância. Portanto, foram determinadas equações para predizer o volume absorvido de oxigênio para as temperaturas de 10±2 ºC e 25±2 ºC, dependendo da umidade relativa na faixa de 75 por cento a 85 por cento e da taxa de permeabilidade a oxigênio da embalagem. Para a temperatura de 25±2ºC a equação é: V = -32,770+10,440*UR-104,385*ln(TPO2), com um R² = 0,9151. Para a temperatura de 10±2ºC a equação é: V=107,321+6,221*UR-105,166 ln(TPO2) com um R² = 0,8729. Dessa forma, o tempo de atividade do sachê pode ser determinado pela equação T = (V-Vi) / (TPO2*A). Utilizando essas equações e, considerando uma embalagem de área 0,05m² por face, com uma permeabilidade de 8,63 cm3.m-2.dia-1, uma umidade relativa de 80 por cento e o volume de oxigênio inicial dentro da embalagem de 2,5 mL, após o envase, o tempo de atividade do sachê quando armazenado a 10±2ºC foi de 435 dias e a 25±2ºC de 666 dias.


Oxygen absorbers have been presenting a growing demand for application in food packaging. Thus, it is important to know the efficiency of those absorbers in different relative humidity and temperatures. Therefore, equations were developed to predict the volume of absorbed oxygen at 10±2 ºC and 25±2 ºC, according as the relative humidity ranging from 75 percent to 85 percent and the oxygen transmission rate through the package. At 25±2ºC the equation was V = -32,770+10,440*RH-104,385*ln(O2 TR), with R² = 0,9151. At 10±2ºC, V=107,321+6,221*RH-105,166 ln(O2 TR) with R² = 0,8729. As a consequence, activity time for the oxygen absorbers can be calculated with the following equation: T = (V-Vi) / (ln(O2 TR*A). Using these equations and considering a packaging area of 0,05m² for each face, oxygen transmission rate of 8,63 cm³.m-².dia-1, relative humidity of 80 percent and an initial oxygen volume inside the package of 2,5 mL, absorber activity times when stored at 10±2ºC and 25±2ºC were 435 and 666 days, respectively.

9.
Ciênc. agrotec., (Impr.) ; 31(6): 1800-1804, nov.-dez. 2007. graf, tab
Artigo em Inglês | LILACS | ID: lil-471699

RESUMO

The main objective of this work was to evaluate the efficiency of oxygen - absorbing sachets at relative humidity of 75 percent, 80 percent and 85 percent and different temperatures, 10±2 ºC and 25±2 ºC. The experiment consisted in determining the O2 absorption under these conditions. A sachet was placed in desiccators with an internal air homogenization system. Aliquots of air were removed at pre-established time intervals and analyzed for oxygen content. The results showed that oxygen absorption by the sachet increased as the relative humidity increased for both temperature. Therefore the oxygen - absorbing sachets were most active under 25±2ºC and 85 percent relative humidity. At ambient condition (25±2ºC/75 percentRH) the rate of oxygen absorbed was 50 mL/day and 18,5 mL/day for 10±2ºC. It was used a totally casualized design with three replicates.


O objetivo principal deste trabalho foi avaliar a eficiência de sachês absorvedores de oxigênio a 75 por cento, 80 por cento e 85 por cento de umidade relativa e diferentes temperaturas, 10±2 ºC e 25±2 ºC. O experimento consiste em determinar a absorção de O2 sob essas condições. Um sachê foi colocado dentro de um dessecador contendo um sistema de homogeneização do ar interno. Alíquotas de ar são retiradas dos dessecadores em intervalos de tempos pré-estabelecido e seu conteúdo de oxigênio analisado. Os resultados mostraram que a absorção de oxigênio pelos saches aumentaram com o aumento da temperatura para ambas as temperaturas. No entanto, os sachês mostraram uma maior eficiência para 85 por cento de umidade relativa e 25±2ºC de temperatura. Na condição ambiente (25±2ºC/75 por centoRH), a taxa de absorção dos sachês foi de 50 mL/dia e 18,5 mL/dia para 10±2ºC. O experimento foi conduzido com delineamento experimental inteiramente casualizado, com três repetições.

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