Monitoring effects on anthocyanins, non-anthocyanin phenolics and ORACFL values of Colombian bilberry (V. meridionale Swartz) during pulping and thermal operations

Abstract

Processing of berries usually degrades anthocyanin and non-anthocyanin phenolics and diminishes antioxidant activity. In Colombia, jelly produced from the fruit of Vaccinium meridionale Swartz is a popular product among consumers. The aim of this study was to determine the effect of jelly processing steps on bioactive components. Analysis of anthocyanins (ACNs) and non-anthocyanin phenolics was performed via HPLC-PDA. Antioxidant activity was assessed by the ORACFL method. The pulping step had the highest impact on ACNs, whose total content was significantly higher in the pomace (747.6 ± 59.2 mg cyanidin 3-glucoside (cyn 3-glu)/100 g) than in the pulp (102.7 ± 8.3 mg cyn 3-glu/100 g). Similarly, pulping caused a significant decrease in flavonols, procyanidins (PACs) and ORACFL values.Despite the effects of processing, Colombian bilberry jelly can be considered a good source of phenolic compounds with high antioxidant activity. The final concentration of ACNs, hydroxycinnamic acids (HCAs) and flavonols, as well as the ORACFL values in this product were comparable to those of fresh cranberry (Vaccinium oxycoccos) and black currant (Ribes nigrum). The results also suggest that the pomace of V. meridionale can be recovered as an excellent source of bioactive compounds.

Keywords

• Vaccinium meridionale
• Pulping
• Thermal processing
• Jelly
• Pomace
• Phenolics