The amplified production of fruit as well as burgeoning demand for plant-made food products have resulted in a sharp increase of waste. Currently, millions of tons of by-products are either being discarded or utilized rather ineffectively. However, these by-products may be processed and further incorporated as functional ingredients in making high-value food products with many physiological and biochemical effects. The chemical analysis of pomace oils using gas chromatography-mass spectrometry (GC/MS) and reversed-phase-liquid chromatography coupled with fluorescence detector (RP-HPLC/FLD) systems led to the identification and quantification of 56 individual lipophilic compounds including unsaturated, polyunsaturated and saturated fatty acids, as well as phytosterols and four homologs of tocopherol. The oils recovered from by-products of Malus spp. (particularly cv. “Ola”) are rich in fatty acids such as linolenic (57.8%), α-linolenic (54.3%), and oleic (25.5%). The concentration of total tocopherols varied among the Malus species and dessert apples investigated, representing the range of 16.8–30.9 mg mL⁻¹. The highest content of total tocopherols was found in M. Bernu prieks, followed by M. cv. “Ola”, and M. × Soulardii pomace oils. A significantly higher amount of δ-tocopherol was established in the oil of M. Bernu prieks, indicating that this species could be utilized as a natural and cheap source of bioactive molecules. β-Sitosterol was the prevalent compound determined in all tested pomace oils with a percentage distribution of 10.3–94.5%. The main triterpene identified in the oils was lupeol, which varied in the range of 0.1–66.3%. A targeted utilization of apple pomace would facilitate management of tons of by-products and benefit the environment and industry.

According to recent reports, the global market for melatonin is worth 700 million USD in 2018 and would reach 2,790 million USD by 2025, growing at a CAGR of 18.9% during 2019 to 2025. Having regard to the prevalence of sleep and circadian rhythm disorders and a clear tendency to increase the demand for melatonin, and the current lack of alternative green and cost‐efficient technologies of its synthesis, the supply of this remedy will not be enough to guarantee melatonin supply and affordability on a global scale. The emergence of naturally occurring melatonin and its isomers in fermented foods has opened an exciting new research area; there are still, however, some obscure points in the efficient microbiological biosynthesis of melatonin. This review summarizes the research progress and recent evidence related to melatonin and its isomers in various foodstuffs. Additionally, one possible way to synthesize melatonin is also discussed. The evidence pointed out that the presence of melatonin and its isomers is not exclusive for grapes and grape‐derived products, because it can be also found in sweet and sour cherries. However, different species of both Saccharomyces and non‐ Saccharomyces yeasts could be used to obtain melatonin and melatonin isomers in the process of alcoholic fermentation biotechnologically. The availability of L ‐tryptophan has been a key factor in determining the concentration of indolic compounds produced, and the utilization of probiotic lactic acid bacteria could help in the formation of melatonin isomers during malolactic fermentation. These approaches are environmentally friendly alternatives with a safer profile than conventional ones and could represent the future for sustainable industrial‐scale melatonin production.

Historically Triticum aestívum L. and Secale cereále L. are widely used in the production of bakery products. From the total volume of grain cultivated, roughly 85% is used for the manufacturing of flour, while the remaining part is discarded or utilized rather inefficiently. The limited value attached to bran is associated with their structural complexity, i.e., the presence of cellulose, hemicellulose, and lignin, which makes this material suitable mostly as a feed supplement, while in food production its use presents a challenge. To valorize these materials to food and pharmaceutical applications, additional pre-treatment is required. In the present study, an effective, sustainable, and eco-friendly approach to ferulic acid (FA) production was demonstrated through the biorefining process accomplished by non-starch polysaccharides degrading enzymes. Up to 11.3 and 8.6 g kg⁻¹ of FA was released from rye and wheat bran upon 24 h enzymatic hydrolysis with multi-enzyme complex Viscozyme^® L, respectively.