Proximate composition and nutritional characterization of Chia enriched yoghurt

Abstract

Yoghurt is a fermented dairy product associated with several beneficial nutritional and health effects. Due to increased demand of yoghurt in Kenya, some processors seek to incorporate synthetic ingredients in order to improve the nutritional value, thickening and stabilizing properties. Besides having good gelling properties, chia seeds (Salvia hispanica L.) are a good source of proteins, omega-3 fatty acids, omega-6 fatty acids, minerals, soluble dietary fiber and phytochemicals. This study sought to develop and determine the proximate composition and nutritional (amino acids, fatty acids, and mineral contents) characteristics of chia enriched yoghurt (CEY). Yoghurt treatments were enriched with chia seeds at either 1.5% m/v (CEY1.5), 2.5% m/v (CEY2.5) or 3.5% m/v (CEY3.5), and 2% cornstarch (CEY0). The results of the proximate composition indicated a significantly higher content of moisture, crude ash, crude fat, crude fiber and carbohydrates in CEY1.5, CEY2.5 and CEY3.5 than in CEY0. In the current study, the composition of calcium, potassium, and phosphorus, was significantly higher in CEY 1.5, CEY2.5 and CEY3.5 than in CEY0, with values increasing with increase in quantity of chia seeds in the formulation. The results for amino acids showed that the essential and non-essential amino acids were significantly  igher in CEY3.5 than CEY2.5, CEY2.5 than CEY1.5 and CEY1.5 than CEY0. In terms of fatty acids profile, the concentration of lauric acid and palmitic acid was significantly lower in CEY1.5, CEY2.5 and CEY3.5 than in CEY0. On the other hand, the concentration of stearic acid, oleic acid, linoleic acid and α-linolenic acid in CEY1.5, CEY2.5 and CEY3.5 was significantly higher than in CEY0. In conclusion, CEY1.5, CEY2.5 and CEY3.5 showed enhanced proximate composition and nutritional (amino acids, fatty acids, and minerals contents) characteristics compared to CEY0, thus chia seeds have a potential to be used in yoghurt for value addition.

Key words: Chia, yoghurt, fatty acids, amino acids, enrichment, minerals, proximate composition