The Effect of Sous-Vide Processing Time on Chemical and Sensory Properties of Broccoli, Green Beans and Beetroots

Vegetables are a natural source of bioactive compounds, however, their content is strongly affected by the preparation methods. The study aimed to find the balance between high health-promoting properties, resulting from well-retained minerals content, and sensory properties by testing different times of sous-vide cooking of vegetables at 85 °C. For each vegetable, broccoli, green beans and beetroots, three times options of sous-vide treatment were individually applied. No effect of sous-vide cooking on dry matter content was found for tested vegetables, with the exception of dry mass loss of beetroots cooked for 180 min. The results of potassium, magnesium, calcium and phosphorus determination, confirmed that the sous-vide technique often allows for the retention of these minerals at a level not lower than in raw vegetables. For both broccoli and beetroots, it was observed that the longer the sous-vide processing time, the lower the color intensity, and in the case of each tested vegetable, the worse the consistency. Therefore, the study proves that this method of heat treatment reduces the loss of minerals and preserves the desired color of studied vegetables.