Physicochemical and Functional Characterization of Pear Leathers Enriched with Wild Bilberry and Blackcurrant Pomace Powders

Abstract

Fruit leathers are convenient, delicious and sophisticated alternatives to natural fruits as a source of nutrients, fibers and bioactive compounds. The present study was conducted to develop new fruit leathers by adding 0.5%, 1.0% and 1.5% wild bilberry (BIPP) and blackcurrant (BCPP) pomace powders in pear leather manufactured with honey (5%), pectin (1%) and lemon juice (2.5%) as additional ingredients. The CIEL*a*b* color parameters, titratable acidity, total phenolics content, total anthocyanins content and DPPH radical scavenging activity were determined in the fruit leathers. In addition, the puncturing force, flexibility and adhesiveness of the fruit leathers were measured and sensory analysis was conducted. The results showed that the addition of pomace powders significantly decreased the lightness, chroma and hue angle and increased the titratable acidity of the fruit leathers while a* values decreased in the leathers with BIPP addition. Flexibility slightly decreased while adhesiveness significantly increased with increasing BIPP and BCPP addition level, changes that were perceived as negative in the sensory analysis. The total phenolic content increased by 2.03, 3.26 and 4.45 times at 0.5, 1.0 and 1.5% BIPP addition, respectively, while only by 1.22, 1.42 and 1.60 times at the same levels of BCPP addition. The newly developed fruit leathers could be recommended as alternative snack foods with high nutritional value and functionality.