Chia Seed Mucilage as a Functional Ingredient to Improve Quality of Goat Milk Yoghurt: Effects on Rheology, Texture, Microstructure and Sensory Properties

Abstract

In contact with water, chia seeds release mucilage (MC), which is a source of various health-promoting compounds including dietary fibres. MC has been previously used as a thickening agent in cow milk yoghurt, but there are no available data on its application in goat milk. In this study, three goat milk yoghurts (without—MC0, with 1.5%—MC15 and with 3% mucilage—MC30) were produced. The rheology, texture, microbial counts, syneresis, microstructure and sensory acceptance of the yoghurts were investigated. The MC addition resulted in a reduced hysteresis area, but increased yoghurt viscosity at lower shear rates. It also improved all texture parameters at both concentration levels, while syneresis values were reduced only in sample MC30. The MC addition promoted lactobacilli viability in both supplemented yoghurts. The texture perceived by sensory evaluation was rated the highest for the sample MC30, which was also the most accepted by consumers overall. Critical attributes that reduced the acceptability of all yoghurts were flavour and acidity. In conclusion, chia seed mucilage can be used as a functional ingredient in goat milk yoghurt to produce an innovative dairy product and meet consumer expectations.