Improving physicochemical stability of highland barley-based milk by the addition of endogenous β-glucan

Abstract

The present investigation was undertaken to develop highland barley milk fortified with functional endogenous β-glucan extracted from the bran. Apparent viscosity, storage stability, ΔBS, TSI, centrifugal sedimentation rate, particle size analysis, zeta potential, and confocal laser scanning microscopy were used to characterize the stability of highland barley milk. The results showed that the addition of β-glucan effectively improved the stability of highland barley milk by increasing the viscosity. The SI of the sample with β-glucan increased after 14 days of storage and the absolute value of zeta potential increased compared with the control one. The contact angle increased significantly from 23.6° to 34.5°. ΔBS showed that the supernatant separation was significantly alleviated. The span of particle size became narrow and the distribution was more uniform. CLSM showed that β-glucan changed the distribution of protein and starch, thus increasing the repulsion between particles to enhance stability. Moreover, the HB milk tended to be stable with an increasing additional amount. Combined with the sensory evaluation, the final concentration of 1.2% (w/v) was selected.