Characterization of salt-preserved orange peel using physico-chemical, microbiological, and sensory analyses

Abstract

A traditional fermentative process typical of North-African countries has been used to develop a new product using orange peels discarded from orange juice making. The impact of different NaCl (5-10-15%), sucrose (3-4-5%) and time (40-65-90 days) conditions on the physicochemical characteristics of the final product (instrumental texture, color, volatile composition) has been analyzed in the present research. Also, consumers' perception, as well as the making process (pH, total soluble solids, sugars, and Plate Count Agar method - PCA) has been studied. Results showed that the main effects and interactions affecting the process were ‘NaCl content’, ‘time’, and ‘NaCl*time’. Although PCA was not significantly different among samples, pH, sugars content, instrumental texture, and volatile composition of the samples suggested a greater transformation in those samples fermented in a 5%-NaCl brine. A higher glucose and fructose consumption and polyalcohols generation, a faster decrease in pH, and a more complex volatile profile (higher alcohol and esters content), suggested that the fermentation process was faster when the NaCl content was low. In addition, although liking was similar for all samples, consumer study results showed that the sample made using a 5% NaCl content could be the one with the best potential success.