Encapsulation of Powdered Rowanberries (Sorbus aucuparia) with Plant Polysaccharides

Introduction. Functional food industry has a stable tendency to use natural plant materials and products. The rowan thrives in Siberian conditions, which makes rowanberries a local raw material of plant origin. The article features the process of encapsulation of bitter plant extracts, which makes it possible to create new functional ingredients. Study objects and methods. The plant extract was obtained from the powder of infrared-dried uncultivated rowanberries harvested in the city of Novosibirsk and the Altai Territory in September 2018 and October 2019. The research compared two parallel encapsulation technologies: spray and freeze drying. The encapsulating matrix vs. IR-dried powder ratio was established experimentally. Konjac and guar gum polysaccharides were used as encapsulating membranes. The content of antioxidants, flavonoids, vitamin C, and β-carotene was determined in the IR-dried rowanberry extract and encapsulated powder. A set of experiments made it possible to compile a new formulation of a cottage cheese dessert with encapsulated functional additive. The dessert was tested for various quality indicators that affect the physicochemical and rheological properties of the product, i.e. moisture, solids content, sugar content, vitamin C, β-carotene, antioxidant capacity, and biologically active flavonoids. Results and discussion. Encapsulation significantly improved the sensory properties of the final material. The physicochemical quality assessment showed that a 1:1 dilution of rowan extract with a food polysaccharide did not affect the content of biologically active substances (with a tolerance of 8%). The physical and chemical quality assessment confirmed the functionality of the dessert: it contained > 15% of the daily physiological requirements of vitamin C, β-carotene, antioxidants, and flavonoids. Conclusion. The paper introduces a novel method of rowan powder encapsulation, which was successfully applied to create a new functional product. The encapsulation technology made it possible to soften the natural bitterness of the raw material. The new functional product demonstrated excellent sensory properties and nutritional value.