Caracterización fisicoquímica y microbiológica de films basados en almidón de camote (Ipomoea batatas) y aceite esencial de orégano (Origanum vulgare) y tomillo (Thymus vulgaris)
No Thumbnail Available
Date
2021
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Universidad Nacional de Trujillo
Abstract
En este estudio se utilizó almidón de camote andino y aceite esencial de orégano (AEO) y tomillo (AET) en 2 concentraciones (1 y 2%) para producir y caracterizar films bioactivos y evaluar su efecto en el tiempo de vida útil de carne de vacuno almacenada a 4 ºC durante 9 días. Los biofilms se caracterizaron según su contenido de humedad, espesor, propiedades mecánicas, permeabilidad, colorimetría y espectroscopía infrarroja por transformada de Fourier (FT-IR). En todos los casos la adición de aceite esencial provocó un amarillamiento del biofilm y una reducción en el contenido de humedad. El espectro FT-IR mostró interacciones entre almidón-lípido. Las propiedades mecánicas evidenciaron un descenso en la Fuerza de tensión (FT) y un aumento en el porcentaje de Elongación (%E) por parte de los biofilms con aceite esencial lo que significa una mejora en las propiedades mecánicas debido a la disminución de la rigidez y un aumento en la elasticidad. También se registró una significativa disminución en la permeabilidad de los films especialmente en los que contenían concentraciones de 2% debido a las propiedades hidrofóbicas de los aceites esenciales. El presente trabajo también mostró que los biofilms que contenían mayor concentración, fueron más eficaces frente a bacterias como Escherichia coli, Staphylococcus aureus y Lactobacillus lactis. Al ser aplicados en carne de vacuno, los biofilms eliminaron en gran medida a las bacterias mesófilas aerobias y E. coli. Los biofilms con aceites esenciales también retrasaron la disminución del pH de la carne producido por bacterias acidófilas presentes en ella y mostraron un efecto antioxidante al retrasar el amarronamiento de la carne asociado a la oxidación de la misma. Por lo tanto, los biofilms basados en camote y aceite esencial de orégano (AEO) o tomillo (AET) pueden aplicarse en la refrigeración de alimentos cárnicos para alargar su vida útil.
ABSTRACT In this study, Andean sweet potato starch and essential oil of oregano (OEO) and thyme (TEO) were used in 2 concentrations (1 and 2%) to produce and characterize bioactive films and evaluate their effect on the shelf life of beef stored at 4ºC for 9 days. The biofilms were characterized according to their humidity, thickness, mechanical properties, permeability, colorimetry and Fourier transform infrared spectroscopy (FT-IR). In all cases, the addition of essential oil meant a yellowing of the biofilm, as well as a decrease in humidity, however, it did not affect their thickness. The FT-IR spectrum showed starch-lipid interactions. The mechanical properties showed a decrease in the Tensile Strength (FT) and an increase in the Elongation Percentage (% E) by biofilms with essential oil, which means an improvement in the mechanical properties due to the decrease in stiffness. and an increase in elasticity. There was also a significant decrease in the permeability of the films, especially those containing concentrations of 2% due to the hydrophobic properties of essential oils. The present work also showed that the biofilms that contained a higher concentration were more effective against bacteria such as Escherichia coli, Staphylococcus aureus and Lactobacillus lactis. When applied to beef, the biofilms largely eliminated the aerobic mesophilic bacteria and E. coli. Biofilms with essential oils also delayed the decrease in the pH of the meat produced by acidophilic bacteria present in it and showed an antioxidant effect by delaying the browning of the meat associated with its oxidation. Therefore, biofilms based on sweet potato and essential oil of oregano (OEO) or thyme (TEO) can be applied in the refrigeration of meat foods to extend their shelf life.
ABSTRACT In this study, Andean sweet potato starch and essential oil of oregano (OEO) and thyme (TEO) were used in 2 concentrations (1 and 2%) to produce and characterize bioactive films and evaluate their effect on the shelf life of beef stored at 4ºC for 9 days. The biofilms were characterized according to their humidity, thickness, mechanical properties, permeability, colorimetry and Fourier transform infrared spectroscopy (FT-IR). In all cases, the addition of essential oil meant a yellowing of the biofilm, as well as a decrease in humidity, however, it did not affect their thickness. The FT-IR spectrum showed starch-lipid interactions. The mechanical properties showed a decrease in the Tensile Strength (FT) and an increase in the Elongation Percentage (% E) by biofilms with essential oil, which means an improvement in the mechanical properties due to the decrease in stiffness. and an increase in elasticity. There was also a significant decrease in the permeability of the films, especially those containing concentrations of 2% due to the hydrophobic properties of essential oils. The present work also showed that the biofilms that contained a higher concentration were more effective against bacteria such as Escherichia coli, Staphylococcus aureus and Lactobacillus lactis. When applied to beef, the biofilms largely eliminated the aerobic mesophilic bacteria and E. coli. Biofilms with essential oils also delayed the decrease in the pH of the meat produced by acidophilic bacteria present in it and showed an antioxidant effect by delaying the browning of the meat associated with its oxidation. Therefore, biofilms based on sweet potato and essential oil of oregano (OEO) or thyme (TEO) can be applied in the refrigeration of meat foods to extend their shelf life.
Description
Keywords
Aceites esenciales, Envase bioactivo, Películas de almidón, Carne de res, Ampliación de vida útil