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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; Lactiplantibacillus plantarum 299v and Lacticaseibacillus rhamnosus GG) on the quality of fermented pumpkin (Cucurbita pepo 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 L. rhamnosus, preceding fermentation by US treatment contributed to an increased bacteria count of 4 logarithmic cycles. In the case of fermentation with L. rhamnosus, the lactic acid content was significantly higher than for L. plantarum. 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. [ABSTRACT FROM AUTHOR]

Introduction. In many countries worldwide, food fortification programs with iodine are carried out to minimise the risk of a deficiency of this element in the diet. However, preliminary studies have shown correlations between antioxidant activity and iodine content. Aim. The aim of this study was to examine the use of cauliflower and carrots as matrices for potassium iodide (KI) and potassium iodate (KIO3) at different concentrations. It was hypothesised that iodine compounds and their concentrations affect the antioxidant activity of fortified cauliflower and carrots. Material and methods. The study tested variable iodine concentrations: 0.023; 0.23; 0.77; 1.30; 2.30 and 3.0 mg KIO3 or KI/100 g. These iodine concentrations were applied to two varieties of carrot and two varieties of cauliflower. After the fortification process and 60, 120, 180, 240, and 320 days of storage, the iodine content was determined. Additionally, after 320 days of storage, the antioxidant activity of all vegetable samples was analysed (based on two free radicals scavenging indices, the DPPH scavenging capacity (DPPH•) and the ABTS scavenging capability (ABTS•+)). Results. Covariance between the iodine compound (KI/KIO3) and the ABTS•+ and DPPH• test results of fortified carrots and cauliflower was noted. For the samples of dried carrots and cauliflower with iodine concentrations from 0.23 to 3.0 mg kg-1 of KI or 0.23 to 1.30 mg kg-1 of KIO3, the free-radical scavenging capacity indices were similar to those for samples not fortified with iodine. However, for the samples of both carrots and cauliflower with KIO3 at 2.30 to 3.0 mg kg-1, the capacity to terminate ABTS•+ and DPPH• was lower than in samples without iodine. This was especially true after storage. Conclusions. Cauliflower and carrots can be good iodine matrices. However, to maximise free radical scavenging indices, iodine should be fortified at concentrations of up to 2.30 mg kg-1. [ABSTRACT FROM AUTHOR]