Effect of incorporating plant-based quercetin on physicochemical properties, consumer acceptability and sensory profiling of nutrition bars

Abstract

Background: Plant-based quercetin is usually produced using fruit and vegetable waste and is sold in the market in powdered form. Since it is already used as a supplement in various foods, a study was conducted to develop calorie rich nutrition bars using plant-based quercetin that may serve as a promising functional snack with high antioxidant property for general consumption by teenagers, adults, athletes and sports persons. This study deals with the development of a novel nutrition bar by utilizing a plant by-product. Methods: Plant based pure quercetin extract powder (98% Premium grade) was procured from HerbaDiet, Arkure Health Care, Rohtak, Haryana (India). Other materials used were: quinoa (Chenopodium quinoa) (Pro nature Organic Foods Pvt. Ltd.); instant white oats (Kellogg's India Pvt. Ltd., New Delhi); canola oil (Jivo Wellness Pvt. Ltd.); jaggery (Village product industries); nuts- comprising almond, cashew, walnut, roasted & salted pistachios (Happilo International Pvt. Ltd.). Objective: The study was carried out in order to formulate calorie and nutrient rich bars for all age-groups with a prime focus on antioxidant-quercetin. Results: The quercetin-based nutrition bar was developed with different levels of quercetin (0, 20, 40, 60, 80 mg 100g-1), in addition to other ingredients including oats, quinoa, nuts, canola oil and jaggery. Addition of quercetin caused a significant (p ≤ 0.05) change in water activity, color and textural attributes of the bars. With the increase in the quercetin content, a significant decrease in the water activity and increase in the lightness (L*) and hardness values of nutrition bar samples were observed. The quercetin enriched nutrition bars also had an increase in total phenolic content as well as antioxidant capacity, as assessed by DPPH radical scavenging activity. Evaluation of overall acceptability and sensory profiling was done for all samples and the one with 60 mg 100g-1 quercetin qualified as the best in sensory attributes. Conclusion: The results revealed that a quercetin-based nutrition bar can be a palatable and promising functional food with high antioxidant property.