Flavour enhancement strategy for herbal beverages and kinetic modelling of their antioxidant and sensory properties in accelerated storage conditions

Abstract

Herbal infusions and beverages are part of culinary practices and home remedies of many ethnic groups globally. Centella asiatica, Enhydra fluctuans, Eryngium foetidum and Marsilea minuta are four important herbs that used to be consumed in different East and South Asian countries due to their health benefit. The herbs are not very acceptable by the millennials due to their off flavour and bitterness. In this study, Centella asiaitica was found to be an appropriate candidate for herbal beverages among the said four herbs. A Centella based beverage was developed that can deliver high antioxidant activity together with acceptable sensory properties. Out of the two common methods of herbal beverage preparation (i.e., infusion and decoction), infused beverage was adopted owing to its better sensory acceptance. The grassy flavour of the Centella infused beverage was masked with Khasi mandarin (Citrus reticulata) peel powder (90% Centella asiatica powder with 10% Khasi mandarin peel powder). Further, the accelerated storage study revealed that Centella asiatica powder was stable during ambient storage conditions (RH 61% and 32 °C), whereas the sensory acceptability, physicochemical properties, and the antioxidant potential of the powder degraded significantly at higher temperature (45 °C and RH 82%) especially with UV exposure. The impact of storage conditions on the most critical quality parameters i.e., colour, pH, and antioxidant capacity was estimated with a first-order degradation model. All the antioxidant capacity values showed different intrinsic rates of decay and the half-life of lipid peroxidation values was shortest among the four antioxidant capacity values. This work reports a unique accelerated stability study protocol to screen the packaging and storage conditions for herbal powders. Additionally, the results suggested, Citrus peel blending is a novel approach to make herbal beverages more acceptable to consumers due to better sensory perception and enhanced stability of the herbal powder.