Physicochemical and Sensory Quality of Probiotic Dahi Fortified With Moringa Leaf Powder

Abstract

Dahi, the set fermented milk of the Indian subcontinent, is a familiar vehicle for probiotic bacteria, and fortifying it with the dried leaf of Moringa oleifera is an appealing way to add protein, minerals and phenolic compounds to a food that people already eat. This narrative review asks what the published literature can and cannot say about the physicochemical and sensory quality of such a product, and it reports no new data. It draws together work on the fermentation and gel structure of dahi, the composition and anti-nutritional constituents of moringa leaf, the behaviour of probiotic strains in fortified fermented milks, and the methods used to judge texture and consumer acceptance. Fortification can improve the nutritional profile, but it may also change acidification, probiotic viability, firmness, water holding, colour and flavour, and the direction and size of each change depend on the dose, the particle size, the strain and the base milk. Sensory evidence is the weakest link: panels are usually small and untrained, scales are applied loosely, and acceptance of a green, slightly bitter product is rarely tested in the consumers who would buy it. The review concludes that low levels of leaf powder are plausible candidates for acceptable fortified dahi, that the evidence does not yet fix an optimum, and it sets out the measurements and panel designs a convincing study would need.