Edible berries are becoming increasingly popular to consume in fresh, dried, frozen or processed forms due to their high content and wide diversity of bioactive compounds with considerable health benefits. Among the wide variety of phytochemicals found in berries are stilbenes, which demonstrate a broad range of biological and pharmacological activities. Their content depends on many factors, including the cultivar, ripening stage, climatic conditions, agronomic management, storage conditions and postharvest management. However, the application of various abiotic and biotic external stimuli could be a strategy for increasing the production of stilbenes in edible berries. To date, several different elicitors, as inducers of plant secondary metabolite stilbenes, have been applied in different studies. This review focuses on the isolation and identification of stilbenes from edible berries and presents the influence of different external stimuli on their profile in grapes.
The fruit processing industry generates enormous amounts of byproducts, which are primarily removed through landfill or incineration. However, these processes cause carbon dioxide and methane emissions and release dioxin into the environment. The management of fruit processing byproducts is important for reducing the amount of food waste that is sent to landfills and for developing strategies through the reuse of these products for valorization and economic added value. Fruit processing byproducts are rich sources of bioactive compounds and fermentable and nonfermentable sugars. Therefore, these materials are very attractive feedstocks for developing integrated multifeed biorefineries that coproduce a wide range of natural products and bioenergy. The studies presented here have shown sustainable strategies for managing fruit processing byproducts via a biorefinery approach to achieve full valorization via a circular economy. The full valorization project proposed five main phases, namely, pretreatment, extraction, dark or aerobic fermentation, anaerobic digestion, and post-treatment, as well as two additional pathways to generate additional bioelectricity. When choosing the appropriate directions for the presented concept, a technoeconomic analysis should be carried out, considering the type of biomass and its availability at the site of the biorefinery and throughout the year of production. Applying the proposed concept of biorefineries in closed-loop technology is a promising way to enhance economic efficiency and decrease environmental influence in accordance with sustainable development.
In recent years, there has been increasing interest in berry fruit processing byproducts, namely, seeds, pulp, and peel, due to the high content of nutritionally valuable ingredients. The market is seeing an increase in the popularity of fermented products, especially those from vegetables or fruits. Fermented fruit pomace can be used as an ingredient or food additive. Many studies have confirmed that the fermentation process can increase the antioxidant activity of plant extracts due to the decomposition of cell walls. The aim of this study was to evaluate the microbiological quality and antioxidant potential of fermented berry pomace (from chokeberry, blackcurrant, raspberry, and strawberry) in terms of its potential use as an alternative source of valuable ingredients for the design of new food products. The scope of this research included assessing microbiological quality, vitamin C and total phenolic compound (TPC) contents, and antioxidant activity using ABTS, DPPH, and FRAP assays. The polyphenolic compound and vitamin C contents, as well as antioxidant activity, depended on the mixture of microbial strains used for fermentation and the type of fruit pomace. The most favorable parameters for TPC, ABTS, DPPH, and FRAP were obtained for chokeberry pomace samples inoculated with yeast cultures. Chokeberry pomace exhibited the highest vitamin C content when inoculated with a mixture of bacteria.
Sustainable development and the circular economy have become key challenges in the modern food sector, calling for innovative solutions that reduce waste and promote the efficient use of resources. The aim of this study was to develop a functional food product by utilizing by-products from chokeberry processing, thereby contributing to circularity in food systems. The integration of design thinking with fermentation of chokeberry pomace is presented in this study as an approach to developing value-added food ingredients. Qualitative consumer research (focus group interviews, n = 36) identified preferences and expectations regarding functional foods containing by-products. Conducted by an interdisciplinary team, the project followed five stages, involving both qualitative and quantitative research. Liquid surface fermentation was performed using Aspergillus niger, selected for its proven ability to enhance the antioxidant capacity and polyphenol content of plant matrices. The optimal process was 2-day fermentation under controlled pH conditions with glucose supplementation, which significantly enhanced the quality and nutritional value of the final product. Antioxidant activity (ABTS, FRAP, CUPRAC assays), total polyphenols, anthocyanins, and proanthocyanidins were determined, showing significant increases compared to non-fermented controls. The outcome was the development of a dried, fermented chokeberry pomace product that meets consumer expectations and fulfils sustainability goals through waste reduction and innovative reuse of fruit processing by-products.