The aim of this master's thesis was to investigate the short-term hot water dipping of cucumber, zucchini squash, bell pepper, tomato, carrot and eggplant on their shelf life. The selected vegetables were dipped in hot water at 40–52 °C for 2-15 minutes and stored at 2–10 °C for 12 to 25 days. The untreated control samples and hot water treated samples were analysed for weight loss, spoilage, colour, firmness, total phenolic content, flavonoids and antioxidative potential during the storage period. Results demonstrate that short-term hot water dipping is more effective in reducing weight loss and spoilage compared to non treated control, with the exception of some vegetables stored at 10 °C. In most cases, a storage temperature of 2–4 °C showed better results than 10 °C, although this effect depended on the type of vegetable. The treated cucumber and zucchini samples retained their green colour better. The firmness of vegetables treated with hot water, was better preserved compared to untreated vegetables, especially at 4 °C, with the exception of cucumbers and carrots. Most of the treated samples generally exhibited better antioxidative potential and contained more total phenols than the control samples, except for cucumbers. In peppers and eggplants, no significant correlation was observed between flavonoid content and hot water treatment, and no clear relationship between flavonoid content and storage temperature was found.
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