| Abstract [eng] |
Increasing food production volumes lead to growing amounts of plant-based processing by-products which, if not efficiently utilized, contribute to global problems. One of such by-products is carrot pomace generated during juice production. However, this raw material still contains significant amounts of dietary fiber, microelements, and bioactive compounds. Nevertheless, its application is limited by the high content of insoluble dietary fiber. A potential solution is the use of enzymes for dietary fiber modification, which is considered an environmentally friendly approach capable of improving functionality and broadening application possibilities. Therefore, the aim of this study was to evaluate the effect of enzymatic treatment of carrot pomace powder on dietary fiber composition, technological and functional properties, as well as their potential application in the development of food supplements. Different commercial enzyme preparations were used in the study, including Pectinex® Ultra Tropical, Celluclast® 1.5 L, Viscozyme® L, and Sternzym® Oilex, containing cellulases, hemicellulases, and pectinases. Enzymatic treatment of carrot pomace powder resulted in changes in soluble and insoluble dietary fiber contents as well as in the ratio of these fractions. The greatest alteration in insoluble dietary fiber was observed after hydrolysis with Viscozyme – its content decreased by approximately 59 % compared to the untreated material, reducing the solubleto-insoluble fiber ratio to 1:1.2. Enzymatic modification also affected technological properties: waterand oil-holding capacities and solubility increased, color characteristics changed, while swelling capacity decreased compared to the untreated sample. In addition, emulsions stabilized with modified carrot pomace powders demonstrated improved stability. The most effective stabilization was achieved using the sample treated with Pectinex enzyme preparation, where 56 % and 62 % of stable emulsion remained after 21 days under static and thermal conditions, respectively. Further evaluation of functional properties revealed that enzymatic hydrolysis increased the content of soluble phenolic compounds and ABTS radical scavenging activity. The strongest prebiotic effect for Lactiplantibacillus plantarum was exhibited by carrot pomace treated with Sternzym enzymes, whose prebiotic index was almost 8 times higher than that of inulin. It is noteworthy that hydrolysis with the Pectinex preparation significantly improved cholesterol and sodium cholate binding capacities under neutral pH: from 19.1 to 42.7 and from 53 to 93.4 mg/g of dry matter, respectively, compared to the raw material. Finally, the potential application of untreated and enzymatically modified carrot pomace powders in the development of synbiotic food supplements possessing prebiotic and probiotic properties was evaluated. After enrichment with L. plantarum, the highest bacterial viability during 3 months of storage was maintained in the untreated sample and reached approximately 8 log10 CFU/g. These results indicate that carrot pomace may serve as a promising matrix for maintaining probiotic bacterial viability while also supplementing the human diet with dietary fiber, that is important for gut heath. |
