Characterization of Post-Production Waste from Winemaking of Selected Vitis vinifera L. Varieties Grown in Temperate Climates and Their Energy Valorization

Abstract

The study assessed the yield and quality as well as the energy potential of biomass from stalks and pomace of four grape varieties, Riesling, Chardonnay, Zweigelt, and Merlot Vitis vinifera L., grown in temperate climate conditions. The research is innovative because the evaluation of the energy potential of biomass originating from Vitis vinifera L. has not been carried out so far in the northern wine-growing regions. Field studies were conducted in 2023 in the Experimental Vineyard of the University of Life Sciences in Lublin, located in southeastern Poland. Biometric yield assessment showed that Chardonnay vines were characterized by the lowest mass of clusters and peduncles, number of berries in the cluster, berry diameter, and peduncle size, and at the same time the highest berry mass among the assessed biotypes. Merlot clusters were characterized by the highest mass of clusters and the largest peduncles. Riesling had the most berries in the cluster, the heaviest peduncles, and the highest share of peduncles in the cluster mass (8.99%). For grape pomace, the LHV values range from 15.98 MJ kgMINUS SIGN 1 for the Chardonnay variety to 16.91 MJ kgMINUS SIGN 1 for Riesling, while for peduncles, these values range from 15.11 MJ.kgMINUS SIGN 1 for Merlot and Riesling to 15.26 MJ kgMINUS SIGN 1 for Chardonnay. The differences in pollutant emissions are more pronounced between grapevine varieties than between types of biomass (pomace vs. peduncles). The greatest variation among varieties was observed for carbon dioxide (CO2) emissions in the pomace category, while the smallest differences were noted for sulfur dioxide (SO2) emissions. Total gas emissions were highest for Zweigelt pomace (7.72 Nm3 kgMINUS SIGN 1) and lowest for Merlot (6.99 Nm3 kgMINUS SIGN 1), while for stalks, Chardonnay had the highest values (6.77 Nm3 kgMINUS SIGN 1) and Merlot the lowest (7.32 Nm3 kgMINUS SIGN 1). The largest variation among varieties was observed in the pomace category. These results indicate differences in exhaust gas emissions for different plant parts and grape varieties, which are relevant for optimizing production processes and ensuring sustainable development.