Assessment of different debittering techniques to valorize orange peel.

Abstract

Different strategies to reduce bitterness of orange peels were assessed in the present research: a) blanching in 2 % NaCl-water (SALT), b) blanching in 1 % Na2CO3-water (ALK), c) blanching in water and fermentation with Lactoplantibacillus plantarum (FR), and d) blanching in water and sugar coating (SUC). Samples were freeze-dried and characterized: total flavonoids and polyphenol contents, volatile composition, and instrumental texture were analyzed. A consumer panel assessed samples’ acceptance, bitterness perception, and further applications of the developed ingredients. Results showed significant differences in total flavonoid and polyphenol contents, being the SALT and SUC the samples the ones with the highest polyphenol, and the ALK and SUC samples the ones with highest flavonoid content. Bitterness perception seemed to be somehow related to TPC, although influenced by other properties of the samples (e.g.: volatile composition). Volatile composition was slightly different among samples but seemed to have an impact on flavor perception. Texture results showed that SALT was the hardest sample and the ALK sample the softest one. SUC and FR samples were the most liked ones, although were perceived as moderately bitter. Further research is needed to better understand bitter perception of processed orange peels to develop highly accepted products.