Optimization of Berry Infusions with High Polphenol Content

OpenAlex İngilizce

Goji berry, also known as wolfberry, is a plant that grows in the Asian region. It is a red-orange elliptical fruit with a sweet, sour taste due to the presence of phenolic compounds. Recently, goji berry is becoming more and more popular because of the health benefits of bioactive ingredients. The present study aims to determine infusion parameters for producing functional beverages rich in bioactive components and suitable for consumption with maximum benefit to human health. In this context, the response surface methodology (RSM) was used for experimental design. Three independent variables were determined, which are temperature (75'95 °C), time (5'15 min), and mass (2'5 g), to optimize the desired quality characteristics in goji berry teas and to evaluate the interactions of the independent variables. The three-variable experimental design was implemented 6 replications in the center point, resulting in 20 total trial patterns. The total phenolic content, total flavonoid content, antioxidant activity, anthocyanin content, and condensed tannin content of the samples were determined. For optimization, it is aimed that goji berry infusions have the values of maximum total phenolic content, total flavonoid content, antioxidant activity, anthocyanin content, and condensed tannin content. As a result of the analysis of variance (ANOVA), a meaningful model for total anthocyanin content, total flavonoid content, condensed tannin content, and phenolic content values could not be established (p<0.05), but statistically significant model was obtained for DPPH (p<0.05). Temperature and mass were found to be statistically significant (p<0.05) on DPPH. Depending on the levels of the selected quality characteristics, the parameters that will provide an optimum formulation of goji berry infusions were suggested as 85.77°C, 5 min., and 5 g, according to the desirability function (0.634). Thus, the parameters of antioxidant capacity, total phenolic substance, total anthocyanin, total flavonoid, and total condensed tannin content were determined to maximize bioactive substances and be beneficial for consumer health.