Aislamiento de la proteína a partir de la torta de sacha inchi (Plukenetia volubilis linneo)

Abstract

The nutritive properties that the sacha inchi almond (Plukenetia volubilis Linneo) has due to its high protein and oils content motivate farmers and companies to start using it to export their products in the future. However, in the vegetal oil extraction process, significant amounts of solid residues are generated. These residues still have valuable nutrients in their composition, which can be taken advantage of and avoid their accumulation. A physicochemical characterization on the fruit, shell, almond and solid residue of the Santander’s department sasha inchi was performed for this study. The study followed the procedures and analytic techniques stated by “Norma Técnica de Colombia” (NTC). The shell yielded high percentages of fiber (76.5%) and carbohydrates (92%). The seed contained the highest fat content reported in literature of 58.5%. The solid residue had protein as its main component (50.1%), followed by fats (22%), carbohydrates (14.5%), ash (9.4%), fiber (5.7%) and humidity (4%). Analyzing the results of the physicochemical characterization of the solid residue, it was decided to obtain the vegetal protein, since the residue is composed by half of it. They also play a very important role in nutrition, which is something that an increasing number of people are looking to improve in their nourishment. Moreover, it is a good alternative to animal protein sources, which would decrease the contamination of the farming industry. A protein isolation procedure was performed on the sacha inchi using the alkaline extraction method with isoelectric precipitation. The variables studied for the exptaction were temperature, pH and p/v relation. The best solubility (33.6%) and extraction (86.6%) percentages were achieved with the skimmed fat residue in a 1:30 p/v ratio. The best conditions for the alkaline extraction and acid precipitation were at 50°C with a pH of 11 and 6. The protein obtained from the saca inchi was also subject to a physicochemical characterization and a sodium analysis. The physiochemical characterization showed a content of 92% protein, 1.8% ash, 0.05% fat, 0.4% fiber and 5.38% carbohydrates, while the sodium analysis yielded a 1.06 ppm of sodium and 4.3ppm of calcium. According to the norm (CODEX, 1989) the percentage of protein obtained is the one of a protein isolate.