Antioxidant content of dark colored berries

B. Ozola and M. Dūma*

Latvia University of Life Sciences and Technologies, Department of Chemistry, Liela Street 2, LV3001 Jelgava, Latvia
*Correspondence: Mara.Duma@llu.lv

Abstract:

Blackberries (Rubus caesius), elderberries (Sambucus nigra L), highbush blueberries (Vaccinium corymbosum L) and black currants (Ribes nigrum) were selected for research on their content of phenolic compounds, including anthocyanins and comparing their content in these berries. Samples were also assayed for ascorbic acid and soluble solid content. The unifying mark of these fruits is purple-black color, which indicates high content of anthocyanins. Analyses of these fruits showed that they contain high biological activity components that justify the uses of these fruits.
The research was done at the Department of Chemistry, Latvia University of Life Sciences and Technologies, year 2019. Berry samples were bought at the supermarket (highbush blueberries) or collected from garden in Jelgava, Latvia (blackberries, elderberries and black currants). All berries were at full maturity. The content of ascorbic acid, total phenols, anthocyanins, flavonoids as well as soluble solids was determined.
Descending order of ascorbic acid content in berries is: black currants > blackberries > elderberries > highbush blueberries. Elderberries had the highest content of anthocyanins, total phenols and flavonoids on average 161.5, 537.9 and 112.6 mg 100 g^-1 FW, respectively. The content of soluble solids changes from 5.83 Brix (elderberries) to 13.67 Brix (black currants).

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Review article: Current research trends in fruit and vegetables wastes and by-products management-Scope and opportunities in the Estonian context

D. Malenica* and R. Bhat

Estonian University of Life Sciences, Insitute of Veterinary Medicine and Animal Siences, Kreutzwaldi 56/5, EE51006, Tartu, Estonia
*Correspondence: malenica.dunja@gmail.com; dunja.malenica@student.emu.ee

Abstract:

Globally on an annual scale, considerable amounts of fruit and vegetables wastes (FVW) are generated in the agri-food industrial sector. Costs insured for safe disposal of FVW remains uneconomical and they can pose a serious environmental hazard if left untreated. However, FVW have high potential for reuse, recycle and recovery, which is an indication that there are productive, sustainable and affordable ways of reducing and tackling them at the industrial levels. Recent years have seen progressive innovative research on FVW management strategies, which has been developed with an idea of reducing wastes and fully exploiting its potential. Further, FVW represents a potential source of valuable compounds and bioactive ingredients. Today, there are many proposed innovative approaches for handling the FVW. These include reintroducing sub-standard fruit and vegetables (small sized or misshaped fruit and vegetable) in the market, reusing FVW for soil amendments, composting, or as an animal feed, and much more. In addition, the extracted bioactive compounds from FVW and by-products can find wide applications as a natural additive in food, cosmetics and/or in pharmaceutical applications. Currently, novel cost effective strategies have been developed for effective valorisation of agri-food wastes and by-products. The field of FVW management is still limited, thus leaving a wide gap for new ideas, novelty and applications of more efficient green techniques for complete utilization of agri-food wastes and by-products. Some of the interesting aspects on wastes and by-products management are discussed in relevance to Europe and in Estonia.

Key words:

bioactive compounds, circular economy, food wastes and loss, livestock feed, waste management