BACKGROUND: Sour cherry (Prunus cerasus L.) stones are the major byproduct of the cherry industry and the efficient management of this biowaste can lead to achieving the food processing sustainability aimed at by the modern food industry. Despite its significant content of lipids, the valorization of cherry stone waste as feedstock for lipid extraction appears to be limited due to the high moisture content. This study explores the primary factors that affect the yield of lipid extraction using Soxhlet, Randall and supercritical carbon dioxide (scCO2) extraction methods, with a particular emphasis on yield optimization for green extraction technologies (scCO2). RESULTS: The investigation revealed an increased lipid extraction yield for scCO2 from 7.4 for dry crushed stones to 20.6 g per 100 g dry weight when the cherry kernels are separated. The high initial moisture content affected all three extraction methods, but mostly impacted the scCO2 extraction, resulting in the co-extraction of an aqueous phase. Lipid and aqueous yield could be manipulated by time, temperature and pressure. However, no observable influence on the composition of fatty acid methyl esters was detected. CONCLUSION: Numerous approaches are shown to enhance the lipid yield from cherry stone waste, depending on the desired outcome. When dealing with wet samples, Randall extraction proves to be the most effective method. On the other hand, scCO2 extraction presents distinct advantages, such as the extraction of food-grade lipids and the co-extraction of a unique aqueous phase, which comes at the expense of a reduced lipid yield. © 2024 The Authors. Journal of Chemical Technology and Biotechnology published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry (SCI).
Enhancing sweetness of vegetables by addition of sucrose or sweeteners can increase acceptance but is not necessarily desirable. An alternative strategy could be to combine vegetables with other vegetables. By offering combinations of vegetables it might be possible to suppress bitterness, enhance sweetness and provide texture variety leading to increased acceptance. The aim of this study was to determine the influence of combining vegetables with other vegetables on sensory properties and acceptance. Carrot (sweet), cucumber (neutral), green bell pepper (bitter) and red bell pepper (sour) were assessed individually and in combination with the other three vegetables in two mixing ratios (1:2 and 2:1). Additionally, four combinations of three vegetables (mixing ratio 1:1:1) were assessed. A trained panel (n = 24) evaluated taste, flavour and texture and a consumer panel (n = 83) evaluated acceptance of all vegetables and combinations. Combining green bell pepper with carrot (1:2 and 2:1) increased sweetness and decreased bitterness. Combining cucumber, carrot or red bell pepper with green bell pepper (1:2) increased bitterness. Mainly sweetness and bitterness were associated with acceptance whereas texture (crunchiness, firmness and juiciness) did not strongly influence acceptance. Cucumber was the most accepted vegetable followed by carrot, red bell pepper and green bell pepper. Acceptance of vegetable combinations can differ from acceptance of individual vegetables depending on vegetable type and mixing ratio. Only 3 of 16 vegetable combinations had higher acceptance compared to the least accepted vegetable in the combination and similar acceptance as the more accepted vegetable in the combination. For 13 of 16 vegetable combinations acceptance did not increase compared to acceptance of individual vegetables. These findings suggest that strategies aimed at increasing vegetable consumption can be devised using specific combinations of vegetables.