Seabuckthorn Berries as a Novel Source of Prebiotic in Yogurt Model.

摘要

Functional foods are defined as foods that have demonstrated physiological benefits and can reduce the risk of chronic disease beyond basic nutritional functions, including maintenance of gut health (Cencic & Chingwaru, 2010). Yogurt fortified with probiotics and fruit is considered a functional food, because it is believed to reduce the risk of chronic gut disease. Due to the demand, nationally and internationally, new combinations of fruits such as seabuckthorn and yogurt have the potential to be exploited in the food industry.;After determining total count of microorganisms the second objective was to determine the effects of seabuckthorn whole fruit (S) and water extractable-polysaccharide materials (SP) on different probiotic bacteria in yogurt using selective media. It was found that after 21 days of cold storage, S and SP both had higher viable bacteria counts of probiotics L. acidophilus and Bifidobacterium lactis, in comparison to the controls (P≤0.05). Results of this study suggest seabuckthorn may serve as a new prebiotic source for functional foods and nutraceutical applications.;The third objective was to determine if Electronic-nose (e-nose) has the potential as a novel tool for differentiating flavours of different yogurts. E-nose results indicated that flavoured yogurt could indeed be separated suggesting that the technique could be applied in areas of food industry for food monitoring, shelf life, and differentiation. The abstract for each chapter describes the thesis objectives in more detail.;The first objective of this study was to determine if seabuckthorn (S) berries could serve as a prebiotic in yogurt, in addition to the antioxidant activity. After, 7 days of cold storage all seabuckthorn yogurt treatments showed significantly higher microbial counts compared to those of the control (P≤0.05) and following 21 days of cold storage, yogurt samples containing 2% seabuckthorn and probiotic Lactobacillus acidophilus had the highest microbial count (P≤0.05). Water-extractable crude materials (CM) and water-extractable polysaccharides (WEP) of seabuckthorn exhibited strong antioxidant activity with an ORAC value of 138.95 ± 0.99 μmol TE/100g and 29.22 ± 3.08 μmol TE/100g respectively.