Development of a Dairy Product Enriched With Oleaster Flour: A Novel Gluten-Free Functional Pudding

This study aimed to characterize the physicochemical, textural, microbiological, bioactive, and sensory properties of milk-based puddings enriched with oleaster flour derived from different parts of the oleaster fruit. Oleaster flesh flour (OFF) and oleaster peel flour (OPF) were added to the puddings at a concentration of 5%, and 1% of sodium alginate was used as a gelling agent. Two control puddings prepared without (C1) and with (C2) sodium alginate, and OFF-containing (OF) and OPF-containing (OP) puddings were analyzed on the first and tenth days of cold storage. Results showed that adding OFF and OPF slightly increased the pH, titratable acidity, and ash content of puddings, while significantly decreasing the syneresis. OF and OP had approximately 3-fold higher total dietary fiber content compared to C1 (p < 0.05). Color parameters indicated that puddings became darker, redder, and less yellow with oleaster flour. Oleaster-enriched puddings were firmer and had higher consistency, cohesiveness, and viscosity index values compared to controls. OFF was found to be more effective in increasing the total phenolic content and antioxidant activity of puddings, showing 1.48- and 4.54-fold higher values than C1, respectively. Protocatechuic, chlorogenic, and vanillic acids were identified as the dominant phenolics in oleaster-enriched puddings. No mold or yeast growth was observed in the puddings. Total mesophilic aerobic bacteria counts were higher in OF and OP; however, the values were within acceptable limits. Although C1 was more preferred sensorily, the scores of the oleaster-enriched puddings were also above the average.