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Kirje Acid composition of wines depending on grapevine (Vitis spp.) cultivars grown in Estonia(Estonian University of Life Sciences, 2025) Rätsep, Reelika; Maante-Kuljus, Mariana; Karp, Kadri; Seeme, Kersti; Moor, Ulvi; Estonian University of Life Sciences. Institute of Agricultural and Environmental Sciences. Chair of Horticulture; Estonian University of Life Sciences. Institute of Veterinary Medicine and Animal Sciences. Chair of Food Science and TechnologyIn Estonia’s very cool climate, excessive acid content in grapes can be a challenge due to delayed ripening. This study aimed to compare the acid profiles of commercial single-cultivar wines produced by Estonian winemakers, and assess the influence of grapevine cultivar. The wines were made from grapes of five different cultivars: ‘Solaris’, ‘Regent’, ‘Leon Millot’, ‘Cabernet Cortis’, and ‘Marquette’. The results revealed significant variation in malic, tartaric, citric, and lactic acid concentrations among the wines. Marquette exhibited the lowest malic acid content (0.3 g L⁻¹), while Leon Millot had the highest (4.4 g L⁻¹). Tartaric acid levels in wines ranged from 2.2 g L⁻¹ in Leon Millot to 4.1 g L⁻¹ in Regent. Citric acid levels varied considerably, with Solaris containing the highest concentration (1.44 g L⁻¹). Marquette had the highest lactic acid content (2.27 g L⁻¹), contributing to its smooth character. Total acid content in wines ranged from 6.9 g L⁻¹ in Marquette to 9.4 g L⁻¹ in Leon Millot, while pH values varied between 2.9 and 3.3. These findings indicate that grape cultivar significantly influences wine acid composition. Contrary to the hypothesis, excessive acid content was not a major issue in commercial wines; however, grape-growing conditions, such as high plastic tunnels, could alter this outcome. This study provides valuable insights for winemakers seeking to optimize acid balance and enhance wine quality in cool-climate viticulture.Kirje Phytochemical characterization of oil and protein fractions isolated from Japanese quince (Chaenomeles japonica) wine by-product(Elsevier, 2023) Ben-Othman, Sana; Bleive, Uko; Kaldmäe, Hedi; Aluvee, Alar; Rätsep, Reelika; Karp, Kadri; Maciel, Larissa Silva; Herodes, Koit; Rinken, ToonikaThe wine industry generates large quantities of by-products each year. Therefore, this work aimed to isolate and evaluate the oil and protein fractions of Japanese quince (Chaenomeles japonica, JQ) press residue, offering a partial utilization of valuable bioactive compounds of wine industry by-products. To study the JQ oil extract yield, composition and oxidation stability, we modified the co-solvent composition during the supercritical CO2 (SC–CO2) extraction of oil by adding different ethanol content. The remaining defatted material was used for the isolation of proteins. The SC-CO2 extraction yielded oil rich in polyunsaturated fatty acids, tocopherols, and phytosterols. The use of ethanol as a co-solvent increased the oil yield but did not enhance its oxidative stability or content of antioxidants. We recovered protein isolate after removing tannins with 70% ethanol extraction in the next step. The JQ protein isolate contained all essential amino acids. In addition to its balanced amino acid composition, the protein isolate exhibited excellent emulsifying properties highlighting its potential as a food additive. In conclusion, JQ wine by-products can be utilized for the extraction of oil and protein fractions which can be used in food or cosmetic product formulation.Kirje Phytochemical characterization of oil and protein fractions isolated from Japanese quince (Chaenomeles japonica) wine by-product : [data](Estonian University of Life Sciences, 2023) Ben-Othman, Sana; Bleive, Uko; Kaldmäe, Hedi; Aluvee, Alar; Rätsep, Reelika; Karp, Kadri; Maciel, Larissa Silva; Herodes, Koit; Rinken, ToonikaThe wine industry generates large quantities of by-products each year. Therefore, this work aimed to isolate and evaluate the oil and protein fractions of Japanese quince (Chaenomeles japonica, JQ) press residue, offering a partial utilization of valuable bioactive compounds of wine industry by-products. To study the JQ oil extract yield, composition and oxidation stability, we modified the co-solvent composition during the supercritical CO2 (SC–CO2) extraction of oil by adding different ethanol content. The remaining defatted material was used for the isolation of proteins. The SC-CO2 extraction yielded oil rich in polyunsaturated fatty acids, tocopherols, and phytosterols. The use of ethanol as a co-solvent increased the oil yield but did not enhance its oxidative stability or content of antioxidants. We recovered protein isolate after removing tannins with 70% ethanol extraction in the next step. The JQ protein isolate contained all essential amino acids. In addition to its balanced amino acid composition, the protein isolate exhibited excellent emulsifying properties highlighting its potential as a food additive. In conclusion, JQ wine by-products can be utilized for the extraction of oil and protein fractions which can be used in food or cosmetic product formulation.Kirje Polyphenols and resveratrol from discarded leaf biomass of grapevine (Vitis sp.): Effect of cultivar and viticultural practices in Estonia(MDPI, 2020) Rätsep, Reelika; Karp, Kadri; Maante-Kuljus, Mariana; Aluvee, Alar; Bhat, Rajeev; ERA Chair for Food (By-) Products Valorisation Technologies (Valortech). Estonian University of Life Sciences; Institute of Agricultural and Environmental Sciences. Polli Horticultural Research Centre; Institute of Agricultural and Environmental Sciences. Estonian University of Life SciencesGrapevine leaves are a major by-product of viticulture practices derived from the leaf-removal from the fruit cluster zone in all vine growing regions. These leaves can be a valuable source of antioxidants to be used in pharmaceuticals or other health-related products. In this study, the leaves of grapevine cultivars were analysed by ultra-high performance liquid chromatograph-diode array detector () for the total polyphenols (TPC) and resveratrol a ected by cultivar, leaf-removal time and viticultural practice. The e ect of cultivar varied yearly, European grapevine cv. ‘Regent’ had increased TPC and resveratrol in comparison to ‘Boskoop’s Glory’, ‘Rondo’ and ‘Solaris’ in 2017, but ‘Solaris’ in 2018. TPC (1213–1841 mg 100 g-1) and resveratrol (1.061 mg 100 g-1) were higher in leaves of interspecific hybrid cvs. ‘Zilga’ and ‘Hasansky Sladky’ during full fruit ripeness. Cv. ‘Rondo’ grown under the polytunnel had decreased TPC in leaves. In conclusion, cultivar selection, viticultural practice and leaf-removal time contribute significantly to the accumulation of total polyphenols and resveratrol. Results of this study will contribute to better utilization of biomass produced in the vineyards, help to decrease the negative environmental impacts, and provide an overview on various factors a ecting the biochemical constituents, especially in leaves.Kirje Polyphenols and resveratrol from discarded leaf biomass of grapevine (Vitis sp.): Effect of cultivar and viticultural practices in Estonia : [data](Estonian University of Life Sciences, 2020) Rätsep, Reelika; Karp, Kadri; Maante-Kuljus, Mariana; Aluvee, Alar; Bhat, RajeevGrapevine leaves are a major by-product of viticulture practices derived from the leaf-removal from the fruit cluster zone in all vine growing regions. These leaves can be a valuable source of antioxidants to be used in pharmaceuticals or other health-related products. In this study, the leaves of grapevine cultivars were analysed by ultra-high performance liquid chromatograph-diode array detector () for the total polyphenols (TPC) and resveratrol a ected by cultivar, leaf-removal time and viticultural practice. The e ect of cultivar varied yearly, European grapevine cv. ‘Regent’ had increased TPC and resveratrol in comparison to ‘Boskoop’s Glory’, ‘Rondo’ and ‘Solaris’ in 2017, but ‘Solaris’ in 2018. TPC (1213–1841 mg 100 g-1) and resveratrol (1.061 mg 100 g-1) were higher in leaves of interspecific hybrid cvs. ‘Zilga’ and ‘Hasansky Sladky’ during full fruit ripeness. Cv. ‘Rondo’ grown under the polytunnel had decreased TPC in leaves. In conclusion, cultivar selection, viticultural practice and leaf-removal time contribute significantly to the accumulation of total polyphenols and resveratrol. Results of this study will contribute to better utilization of biomass produced in the vineyards, help to decrease the negative environmental impacts, and provide an overview on various factors a ecting the biochemical constituents, especially in leaves.Kirje Recovery of polyphenols from vineyard pruning wastes - shoots and cane of hybrid grapevine (Vitis sp.) cultivars(MDPI, 2021) Rätsep, Reelika; Karp, Kadri; Maante-Kuljus, Mariana; Aluvee, Alar; Kaldmäe, Hedi; Bhat, Rajeev; ERA-Chair for Food (By-) Products Valorisation Technologies (VALORTECH). Estonian University of Life Sciences; Polli Horticultural Research Centre. Institute of Agricultural and Environmental Sciences; Institute of Agricultural and Environmental Sciences. Estonian University of Life SciencesGrapevine shoots and canes represent a significant amount of biomass, considered as a waste in viticulture. In cooler climates, grapevines are pruned in the autumn (October) and spring (March) due to harsh winter conditions (e.g., snow, low temperatures), and large amounts of biomass are produced at these different pruning times. This work was undertaken in order to investigate the potential of vineyard pruning waste for recovery of polyphenolic compounds for biomass valorization. Qualitative and quantitative analyses of grapevine shoot and cane polyphenols, including flavonoids and stilbenoids were performed using UHPLC MS/MS method. The results revealed the flavonols (quercetin) to be the most abundant compounds in shoots among all the three cultivars screened (Zilga, Hasansky Sladky, Rondo). Stilbenoids (ε-viniferin) dominated in the canes, while increased level of flavonols with lower contents of stilbenoids was detected in the endodormant canes, and higher amounts of flavanols and stilbenoids were recorded in eco-dormant canes. In conclusion, the content of polyphenols in grapevine shoots and canes differed among the cultivars and dormancy phases. The results generated from the present study contribute to the sustainable and environmentally friendly viticulture practice via valorization of vineyard pruning wastes.Kirje Recovery of polyphenols from vineyard pruning wastes - shoots and cane of hybrid grapevine (Vitis sp.) cultivars : [data](Estonian University of Life Sciences, 2021) Rätsep, Reelika; Karp, Kadri; Maante-Kuljus, Mariana; Aluvee, Alar; Kaldmäe, Hedi; Baht, RajeevGrapevine shoots and canes represent a significant amount of biomass, considered as a waste in viticulture. In cooler climates, grapevines are pruned in the autumn (October) and spring (March) due to harsh winter conditions (e.g., snow, low temperatures), and large amounts of biomass are produced at these different pruning times. This work was undertaken in order to investigate the potential of vineyard pruning waste for recovery of polyphenolic compounds for biomass valorization. Qualitative and quantitative analyses of grapevine shoot and cane polyphenols, including flavonoids and stilbenoids were performed using UHPLC MS/MS method. The results revealed the flavonols (quercetin) to be the most abundant compounds in shoots among all the three cultivars screened (Zilga, Hasansky Sladky, Rondo). Stilbenoids (ε-viniferin) dominated in the canes, while increased level of flavonols with lower contents of stilbenoids was detected in the endodormant canes, and higher amounts of flavanols and stilbenoids were recorded in eco-dormant canes. In conclusion, the content of polyphenols in grapevine shoots and canes differed among the cultivars and dormancy phases. The results generated from the present study contribute to the sustainable and environmentally friendly viticulture practice via valorization of vineyard pruning wastes.Kirje Toidukadude vähendamise võimalused jahu-, pagari- ja kondiitritööstuses(Eesti Maaülikool, 2024) Voica, Daniela; Bahrim, Gabriela-Elena; Socaci, Sonia Ancuța; Rivis, Adrian; Raba, Diana; Karp, Kadri; Sacchetti, Gianni; Martino, Laura deKuna praegu on toidujäätmete vähendamine kogu toiduahelas talust tarbijani hädavajalik, on vaja vastu võtta strateegia, mis käsitleb vajalikke konkreetseid meetmeid nii Euroopa kui ka siseriiklikul tasandil, eesmärgiga – piirata toidu raiskamist nii tehnoloogilistes tootmisvoogudes, – aga ka toiduainete tarneahela muutmine elanikkonna jaoks tõhusamaks. Ühtse lähenemisviisi jaoks defineerime selles ahelas esinevad mõisted toidujäätmete kohta, sest segadust tekitavad sellised väljendid nagu toiduraiskamine, toidukadu ja bioloogiline raiskamine ja mitte ainult. Käesoleva kursusematerjali väljatöötamise eesmärk on viia vastavusse toidujäätmete vähendamise üldiste suundumustega toiduahelas kahes erinevas etapis. • töötlemise etapp jahvatus-, pagari- ja jahutoodete tööstuses: defineerime igas etapis terve tehnoloogilise protsessi käigus registreeritud toidukaod (food loss), millele liidetakse tehnoloogiline protsessi käigus tekkivad jäätmed (food waste); • jahvatus-, pagari- ja jahutoodete ladustamise/lõpptarbijale turustamise etapp: defineerime toidujäätmed ladustamise ja lõpptarbijani turustamise ahelas toiduainete ladustamise ja realiseerimise etappidest tekkivate toidujäätmetena.