Effect of industrial bleaching on the physicochemical and nutritional quality of non-allergenic lecithin derived from rice bran oil (Oryza sativa L.)

Abstract

The demand for lecithin has increased due to the need for plant-derived products, its important role in health benefits, and the wide range of industrial applications. However, most studies with lecithin use allergenic sources such as soy and egg yolk. Lecithin can be used in the crude form or modified with chemical by the bleaching process in order to quality proprieties. Therefore, we produced lecithin from a non-allergenic source (rice bran oil) by water degumming and evaluated the physicochemical and nutritional properties of natural and bleached lecithin by addition of hydrogen peroxide in an industrial scale. The physicochemical parameters indicated the quality of 12 lecithin samples. From these, 5 and 2 simples of natural and bleached lecithin, respectively, achieved FAO quality recommendations (acid value < 36 mgNaOH/g; hexane insoluble <0.3%; acetone insoluble from 50 to 60%; peroxide value < 10 meq/kg; and moisture <1%). From the multivariate analysis, it was observed that the bleaching process resulted in the improvement of physicochemical parameters, reduction of moisture and depigmentation of lecithin. Natural lecithin showed a greater tendency to accumulate phospholipids, tocopherols, tocotrienols, palmitic, stearic, and linolenic acids, while bleached lecithin stood out for accumulating γ-oryzanol, δ-tocotrienol, oleic and linoleic acids. In this paper, we suggest that the by-product of rice bran oil is a potential source to produce a non-allergenic, nutritious and safe lecithin, especially when the bleaching process is applied, which can contribute to quality enhancement on an industrial scale.