The Effect of Ultrasound and Lactic Acid Fermentation on the Selected Quality Parameters and Bioactive Compounds Content in Fermented Pumpkin ( L.).

Increasing the consumption of fruit and vegetables can be achieved by creating new products. A promising method seems to be the directed fermentation of vegetables. The aim of this study was to investigate the effect of ultrasonic pretreatment (US; 25 kHz; 5 min) and the lactic acid bacteria strain (LAB; 299v and GG) on the quality of fermented pumpkin ( L.). The pumpkin was inoculated with 5 log CFU/g of specific LAB strain. Fermentation was carried out for 7 days at 35 °C. Some samples were US treated at the washing stage. During fermentation, there was an increase in the LAB count of 3 logarithmic cycles compared to the initial inoculum. For , preceding fermentation by US treatment contributed to an increased bacteria count of 4 logarithmic cycles. In the case of fermentation with , the lactic acid content was significantly higher than for . These samples are also characterized by higher sensory properties, desirability of taste, and overall desirability. Fermentation contributed to a decrease in carotenoid and phenolic compounds content and an increase in the antioxidant capacity of the pumpkins, regardless of the bacterial strain.