Enriched functional carrot smoothie with biosynthesized phenolic compounds

Abstract

Carrots are worldwide highly consumed due to their sensory characteristics and health-promoting properties. However, their low phenolic/antioxidant levels may be greatly increased with abiotic stresses. Accordingly, phenolic/antioxidant enhancements and related phenylalanine ammonia-lyase (PAL) activity of carrot shreds under different treatments (UVc radiation and hyperoxia conditions) were studied after a pre-enrichment incubation of 72 h at 15ºC. Subsequently, a carrot smoothie prepared from enriched carrot shreds was heat-treated (90ºC for 30 s) and stored at 5ºC up to 14 days. Heat-treated smoothies showed a good physicochemical and microbiological quality (<6 log CFU g-1) after 14 days at 5ºC, although those non-irradiated samples registered lower psychrophilic and yeasts and molds levels. Heat-treated smoothie from non- irradiated shreds stored under hyperoxia conditions, showed the highest total phenolic content of 13,82 mg ChAE kg-1 fw (87 % chlorogenic acid) after 14 days at 5ºC. Total phenolics content was in accordance with PAL and total antioxidant capacity. Conclusively, a pre-enrichment incubation of carrot shreds under hyperoxia conditions allowed to obtain a functional smoothie with great phenolic levels and good microbiological and physicochemical quality up to 14 days at 5ºC.