Production of prebiotic aubasidan-like β-glucan from Aureobasidium thailandense NRRL 58543 and its potential as a functional food additive in gummy jelly

Abstract

To enhance the yield of Aureobasidium thailandense NRRL 58543 β-glucan, effects of medium ingredients and their optimal concentrations were investigated. The highest yield of β-glucan (37.73 g/L) was obtained in the medium containing sucrose, NaNO3 and sunflower oil at concentrations of 60 g/L, 0.6 g/L, and 81.7 mL/L, respectively. The low molecular weight (LMW) β-glucan (78 kDa) was assessed its prebiotic property in comparison to the native one (>410 kDa). The growth of the probiotics, Lactobacillus casei and L. brevis, was significantly enhanced, although a higher growth was observed in the medium containing the native β-glucan. In addition, the native β-glucan was resistant with simulated salivary and gastrointestinal juice. The addition of β-glucan (2.5 and 5 g/L) in gummy jellies resulted in the increase of the color intensity, hardness, gumminess, and chewiness, while the springiness and cohesiveness decreased compared with the control. The highest score of overall acceptability (7.83 ± 0.75) according to 9-point hedonic scale was obtained from the gummy jellies with 0.5% β-glucan that could be stored at room temperature for seven days without microbial growth. Our findings suggest that A. thailandense β-glucan exhibits an immense potential in the food industry as a functional ingredient and texturing agent.