Effect of Soluble Dietary Fibers from Larix Dahurica on Dairy Bioproducts

Abstract

Wood extracts of Daurian larch (Larix gmelinii) serve as raw material for the prebiotic food additive called Lavitol Arabinogalactan. Larch arabinogalactan is a soluble dietary polysaccharide fiber with a wide range of preventive effects. Fermented dairy products fortified with larch arabinogalactan become functional products with valuable therapeutic activities. This research featured the effect of various doses of larch arabinogalactan on fermentation of normalized milk mixes and the quality profile of the finished dairy bioproduct. The authors determined the optimal dose of dietary fiber, established its prebiotic properties, and determined the physicochemical profile of the final functional product. The experiments involved lyophilized starter on pure cultures of Str. thermophilus, Lac. delbrueckii subsp. Bulgaricus, and B. bifidum. The optimal cultivation temperature was (38 ± 2) °C. Larch arabinogalactan was added to normalized milk mixes in an amount of 0.5–2.5 %. The authors determined the active acidity during fermentation and established a direct relationship between the increase in acidity and the increase in the mass fraction of larch arabinogalactan. The study also involved the lactic acid microbial count and the bifidobacterial count in the fermented mixes. The viable microbial count in the fortified samples demonstrated lactic acid microorganisms (107–109 CFU/cm3) and bifidobacteria (106–108 CFU/cm3). The optimal dose of larch arabinogalactan proved to be 1.5 %. In this research, 0.5 L of the new functional dairy bioproduct was able to cover 36.8 % of human physiological daily need for dietary fibers.