Publication:
Formulación de una lámina comestible a base de almidón de farináceos con adición de bacteriófagos.
Formulación de una lámina comestible a base de almidón de farináceos con adición de bacteriófagos.
Authors
Muñoz-Rodríguez, Nydia E.
Embargoed Until
Advisor
Pérez-Muñoz, Fernando
College
College of Agricultural Sciences
Department
Department of Food Science and Technology
Degree Level
M.S.
Publisher
Date
2012
Abstract
El cultivo de tubérculos en Puerto Rico no satisface la demanda local y frecuentemente no puede competir con los productos importados en precio. Una manera de darle valor agregado a los tubérculos es procesarlos para la producción de almidón, el cual tiene muchas aplicaciones en la industria alimentaria. El propósito de esta investigación es estudiar la producción de almidón para la elaboración de láminas comestibles antimicrobianas. La extracción de almidón se realizó a partir de ñame, yautía, yuca y batata a través de molienda húmeda aplicando un tratamiento químico de inactivación enzimática. La caracterización se basó en el tamaño y forma del gránulo, color, temperatura de gelatinización y análisis proximal. Se utilizaron soluciones de ácido cítrico y bisulfito de potasio para la inactivación enzimática en las siguientes proporciones (1%:0%, 1%:0.25%, 1%:0.50%, 1%:1%), respectivamente. En las formulaciones utilizadas para la elaboración de las láminas comestibles se mantuvo fija la cantidad de agua y se varió el contenido de almidón y plastificante. Las propiedades mecánicas y de barrera al vapor de agua de las láminas fueron evaluadas. Se encontró que la combinación de 1%:1% de ácido cítrico y bisulfito de sodio fue la más efectiva para inactivar las enzimas en los tubérculos. Los almidones presentaron formas: esféricas, esférica-truncadas, elípticas y piramidales. El hilio se desarrolló de forma concéntrica en el almidón de yautía, yuca y batata, y de forma excéntrica en el almidón de ñame. El tamaño promedio de los gránulos se encuentra entre 9µm y 24µm, presentando el mayor tamaño en el almidón de ñame. Los estudios de calorimetría diferencial de barrido (DSC) mostraron un pico endotérmico correspondiente a la gelatinización con un rango de Tmax de 65-80ºC. El almidón de yuca presentó una blancura total mayor con un valor de IB = 96.01 y un valor de IA = 1.97. En términos de composición química, el contenido de proteína, cenizas, grasas y fibra fue bajo, indicando un grado de pureza alto en los almidones obtenidos. El contenido de amilosa fue similar en ñame y yuca, de igual manera para batata y yautía teniendo estos últimos los valores más altos. Se observó que a medida que aumenta el plastificante disminuye la fuerza tensil y el porcentaje de elongación aumenta. La permeanza disminuye cuando aumenta la cantidad de almidón. Después de comparar las láminas obtenidas de las diferentes formulaciones en término de las propiedades evaluadas se seleccionó la que estaba compuesta iv por 4g de almidón de yuca y 20% de glicerol (w/w) de materia seca para adicionarles bacteriófagos. Los bacteriófagos usados en esta investigación tenían especificidad para la bacteria Staphylococcus aureus con un ciclo lítico de infección. Se adicionó el bacteriófago en las siguientes cantidades; 0, 103 y 107 UFP/mL. La propiedad antimicrobiana de las láminas fue evaluada por el método de difusión en agar, encontrándose que hubo un efecto inhibidor con ausencia de la formación de un halo de inhibición alrededor de las láminas comestibles. Estos resultados sugieren que el fago no tiene movilidad en la lámina ni en el agar.
Root crops in Puerto Rico do not satisfy the local demand and often cannot compete with imported product in terms of price. A novel way to add value to these tubers roots is their processing for starch production, which has many applications in the food industry such as stabilizer, in coating and edible film. The purpose of this research is to study the production of starch for the elaboration of antimicrobial edible films. Starch extraction from yams, taro, cassava and sweet potato was achieved through wet milling using a chemical treatment for the enzyme deactivation in the tubers. Citric acid and potassium bisulfite solutions were used for enzyme deactivation in the following proportions (1%:0%, 1%:0.25%, 1%:0.50%, 1%:1%), respectively. The starch characterization was based on the color, size and shape of the granule, gelatinization temperature and proximal analysis. It was observed that the 1%:1% citric acid and sodium bisulfite combination was most effective to inactivate enzymes in tubers. Cassava starch presented a higher total whiteness with a value of WI = 96.01 and a value of YI = 1.97. Average granule size was between 9-24μm. Granules showed different shapes; spherical, spherical- truncated, elliptic and pyramidal depending on their source. Differential scanning calorimetry (DSC) studies showed an endothermic peak corresponding to gelatinization with a range of Tmax of 65-80 ° C. In terms of chemical composition of protein, ash, fat and fiber content were low, indicating high purity of the starch. Amylose content was similar in yam and cassava, likewise for sweet potato and taro; the latter having the highest values. It was observed that with increasing concentration of plasticizer tensile strength decrease and the elongation percentage increases. It was also observed that the permeance decreases when increasing the amount of starch. After comparing the edible films obtained from the different formulations in terms of the evaluated properties was selected that was composed of cassava starch 4g and 20% glycerol (w / w) dry matter to add bacteriophages. Bacteriophages used in this study were specific for the bacteria S. aureus with lytic cycle of infection. Bacteriophages were added in the following amounts: 0, 103 and 107 PFU / mL. The antimicrobial property of the films was evaluated by the agar diffusion method; it was observed an inhibitory effect without an inhibition zone formation around the edible films. These results suggest that the phage has no mobility in the film or in the agar.
Root crops in Puerto Rico do not satisfy the local demand and often cannot compete with imported product in terms of price. A novel way to add value to these tubers roots is their processing for starch production, which has many applications in the food industry such as stabilizer, in coating and edible film. The purpose of this research is to study the production of starch for the elaboration of antimicrobial edible films. Starch extraction from yams, taro, cassava and sweet potato was achieved through wet milling using a chemical treatment for the enzyme deactivation in the tubers. Citric acid and potassium bisulfite solutions were used for enzyme deactivation in the following proportions (1%:0%, 1%:0.25%, 1%:0.50%, 1%:1%), respectively. The starch characterization was based on the color, size and shape of the granule, gelatinization temperature and proximal analysis. It was observed that the 1%:1% citric acid and sodium bisulfite combination was most effective to inactivate enzymes in tubers. Cassava starch presented a higher total whiteness with a value of WI = 96.01 and a value of YI = 1.97. Average granule size was between 9-24μm. Granules showed different shapes; spherical, spherical- truncated, elliptic and pyramidal depending on their source. Differential scanning calorimetry (DSC) studies showed an endothermic peak corresponding to gelatinization with a range of Tmax of 65-80 ° C. In terms of chemical composition of protein, ash, fat and fiber content were low, indicating high purity of the starch. Amylose content was similar in yam and cassava, likewise for sweet potato and taro; the latter having the highest values. It was observed that with increasing concentration of plasticizer tensile strength decrease and the elongation percentage increases. It was also observed that the permeance decreases when increasing the amount of starch. After comparing the edible films obtained from the different formulations in terms of the evaluated properties was selected that was composed of cassava starch 4g and 20% glycerol (w / w) dry matter to add bacteriophages. Bacteriophages used in this study were specific for the bacteria S. aureus with lytic cycle of infection. Bacteriophages were added in the following amounts: 0, 103 and 107 PFU / mL. The antimicrobial property of the films was evaluated by the agar diffusion method; it was observed an inhibitory effect without an inhibition zone formation around the edible films. These results suggest that the phage has no mobility in the film or in the agar.
Keywords
Almidón,
Bacteriófagos
Bacteriófagos
Usage Rights
Persistent URL
Cite
Muñoz-Rodríguez, N. E. (2012). Formulación de una lámina comestible a base de almidón de farináceos con adición de bacteriófagos. [Thesis]. Retrieved from https://hdl.handle.net/20.500.11801/1305