A Sustainable Approach for the Development of Innovative Products from Fruit and Vegetable By-Products

The waste generated by small-scale ultra-fresh juice producers, such as bistros and restaurants, has been little studied so far, mainly because it is unevenly distributed and dissipated in the economic ecosystem and would require high costs associated with transportation and subsequent recovery of bio composites. The present article seeks to offer solutions by providing sustainable methods to reduce their waste losses to a minimum and transform them into valuable products, with affordable equipment and techniques. The study focuses on the preliminary phase of quantitative analysis of fruit and vegetable by-products generated on a small scale, the results showing a mean 55% productivity in fresh juices. Due to the high amount of remnant water content in waste, a new process of mechanically pressing the resulting squeezed pulp was introduced, generating an additional yield in juice, ranging from 3.98 to 51.4%. Due to the rising trend in healthier lifestyle, the by-products were frozen or airdried for conservation in each of the processing stages, and the total phenolic compounds and antioxidant activity were analyzed in order to assess the traceability of these bioactive compounds to help maximize their transfer into future final products. The polyphenols transferred into by-products varied between 7 and 23% in pulps and between 6 and 20% in flours. The highest DPPH potential was found in flours, up to three-fold in comparison with the raw material, but the high dry substance content must be accounted for. The results highlight the potential of reusing the processing waste as a reliable source of bioactive compounds.