Avaliação físico-química de óleo de semente de uva extraído por diferentes métodos

Abstract

There is a great interest of the food industry in reducing the waste generated during the production of their products. The wine industry typically fertilizes vineyard soil or even produces animal feed from grape skins, pomace, seeds, and stems. However, if improperly disposed of in the soil, it can lead to contamination, resulting in various environmental problems, because they are waste materials characterized by a high concentration of organic matter, fibers, and minerals. So, one of the most interesting alternatives to prevent this, is the production of subproducts from these residues, such as grape seed oil extraction. There are many methods to carry out this procedure. The oil extraction method, based on chloroform, methanol, and water, was developed by E.G. Bligh and W.J. Dyer in 1959, and it is considered a cold extraction method. On the other hand, the Soxhlet method is a continuous process in which the sample is extracted through heated solvent in continuous flow until complete extraction is achieved. Thus, this study aimed to compare the Soxhlet and Bligh Dyer methodologies for grape seed oil extraction and evaluate the physicochemical quality of the extracted oil. The Bligh-Dyer method proved to be an inefficient extraction method, while the Soxhlet method provided satisfactory results. Subsequently, the obtained results were subjected to ANOVA, when there was a significant difference between the averages was applied tukey test in the Minitab Statistical Software. The physicochemical analyzes in both methods were mostly out of the standards required by legislation, showing no significant difference (p>0,05) in the iodine index and refractive index.