Turning pork processing waste into value-added chemicals for the food industry

Winterization is a method to modify the characteristics of oils and fats to provide added value by concentrating the unsaturated fatty acids. The purpose of this study is to characterize a residue from pork processing and evaluate two different fractionation methods via winterization. Furthermore, the fatty-acid composition and the chemical characterization were determined from the grease waste and the fractions obtained after fractionation. The untreated grease waste showed an acidity index of 0.57 mg KOH/g, a peroxide value of 10.74 mEq/kg, 56.45% unsaturated fatty acids and 43.55% saturated fatty acids, with the predominance of oleic, linoleic and palmitic acids. The experiment, which was performed in two cooling stages and stirred at 600 rpm, showed a decrease of 27.89% in the saturated fatty-acid content, which predominantly consisted of oleic, palmitic and stearic fatty acids. The winterization process improved the quality of the grease waste, reduced the peroxide value and concentrated the unsaturated fatty acids.