بررسی ویژگیهاي فیزیکوشیمیایی و ساختاري فیلم هاي خوراکی پروتئین کنجاله کنجد حاصل از دو روش استخراج قلیایی و نمکی

In recent years, biopolymers have been considered as a good replacement for plastic materials from petroleum derivatives in the field of packaging. Therefore, the purpose of this study was to investigate the production of a biodegradable edible film of sesame meal proteins by two different protein extraction methods including alkali and salt extraction. In these films, glycerol was used as a plasticizer in three concentrations of 40%, 45%, and 50% and zinc oxide nanoparticles were used in three concentrations of 1%, 3% and 5%. According to the results, it was shown that the thickness of films made from protein by alkaline and salt methods increased with increasing nanoparticle concentration and increasing glycerol concentration; however, the thickness of the protein film was higher by alkaline method than the salt method. The moisture and solubility content increased with increasing glycerol concentration, and also in the constant concentration of glycerol, the addition of nanoparticles decrease moisture content and film solubility content. However, the effect of glycerol and nanoparticles on the salt-based protein film was less than the alkaline method. Also, the moisture and solubility content in the salt method was higher. The results of the comparison of the means showed that in both types of protein films, the addition of the nanoparticle and also the increase of glycerol concentration significantly increased the opacity of the films. According to the results, the amount of opacity and, therefore, the photoconductive property of protein films by the alkali method was significantly higher than that of saline protein films. Fouriertransform infrared spectroscopy (FT-IR), introducing new connections between polymer and zinc oxide nanoparticles in alkaline and saline methods. In the study of the film structure it was shown that the control protein film had a smooth surface, indicating the uniformity of the structure of these composite films, with an increase in the percentage of heterogeneous and rough tissue nanoparticles observed at the film surface, which could lead to aggregation and due to their high concentration the non-uniform distribution of nanoparticles in the polymer bed. [ABSTRACT FROM AUTHOR]