Fortification of Cow Milk with Moringa oleifera Extract: Influence on Physicochemical Characteristics, Antioxidant Capacity and Mineral Content of Yoghurt

Abstract

Background: Fermented dairy products are known for their many positive effects on human health and are consumed worldwide. The supplementation of food with plant extracts as sources of valuable nutritional compounds has recently gained a lot of attention. Milk and fermented products are deficient in bioactive components such as phenolic compounds and iron. Moringa oleifera leaf extract is rich in vitamins, minerals (iron), polyphenols, flavonoids, tannins and proteins. Its addition to milk before fermentation might represent an excellent way to enrich fermented milk products. Methods: Yoghurts enriched with moringa extract (ME) (1, 3 and 4-%, v/v) were produced and compared to a control yoghurt without ME. In all samples, acidity, microbiological parameters, syneresis and water holding capacity, rheology parameters, total colour difference, mineral content, total phenols and antioxidant capacity (FRAP method) and sensory properties were determined. Results: The addition of ME to milk before fermentation resulted in a shorter fermentation time, lower yoghurt pH, increased growth of yoghurt bacteria, better rheological properties and an increased total phenols content as well as antioxidant capacity of yoghurts. Moreover, yoghurts with ME addition had a higher mineral content and gained a better sensory score when compared to the control sample.