Natural food colorant from blackcurrant spray-dried powder obtained by enzymatic treatment: Characterization and acceptability

Abstract

Blackcurrant juice extraction was optimized by enzymatic maceration. A Box–Behnken experimental design was used considering the effect of enzyme concentration, temperature, and treatment time over the total polyphenolic content (TPC), antioxidant capacity (AC), and juice yield. Under the obtained optimal conditions (200 ppm enzyme, 45°C and 60 min), a 2.4-fold increment for TPC, 2.8-fold for AC, and 2.7-fold for total monomeric anthocyanins (ACY) were observed, along with a 15% increase in juice yield. The juice was spray-dried and the powder was tested as an ingredient in a jelly dessert. An attractive color product was obtained, also containing blackcurrant bioactive compounds (0.56 ± 0.03 mg GA/g, 0.20 ± 0.02 mg cyd-3-glu/g and 0.16 ± 0.02 mg of GA/g for TPC, ACY, and AC, respectively). This jelly was stable regarding syneresis and antioxidant compounds for 15 days at 4°C. The developed blackcurrant powder could be useful as natural colorant and source of bioactive compounds for several food applications. Practical applications: An efficient extraction process of blackcurrant juice by enzymatic treatment of ground fruit was achieved. As a result of the process, it was possible to improve the extraction of bioactive compounds and also increasing antioxidant activity. A fruit juice powder was obtained from the enriched juice by spray-drying. The blackcurrant powder showed relatively good physical characteristics and potential functional properties. The use of this powder as a natural colorant in a jelly dessert showed promising results. The ingredient not only enriched the product with bioactive components, but also provided a stable and attractive color. Moreover, the gel properties were improved and the jelly showed very good acceptance in the consumer’s perception test. These results prove that this ingredient has good potential to be used as natural colorant and functional additive in food.