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The volatile fraction investigated by means of HS-SPME/GC–MS technique, the extractable color in terms of ASTA units, and the pungency measured on the Schoville scale of different experimental Capsicum annuum powders, designed for food industry, were evaluated in this study. In particular, six Capsicum annuum cultivars were included; fresh fruits were cultivated, harvested, dried and grinded to obtain different chilli powder samples that were analyzed and compared with an additional sample purchased from the market. Extractable color ranged between 36.9 ± 1.5 and 144.2 ± 0.8 ASTA units, while pungency was from 999 ± 42 to 47,814 ± 971 SHU units, showing an inverse trend between these two parameters. The volatile fraction of samples resulted to be composed of 64 volatiles belonging to different chemical classes among which terpenes and pyrazines were the most represented ones. The differences and similarities among the chilli pepper varieties were visualized by means of Principal Component Analysis (PCA) as by Heat Map analysis.

Physical properties, microbiological quality and volatile compounds of sous-vide-processed carrots and Brussels sprouts were analysed after 1, 5 and 10 days of refrigerated storage. Similar analyses were performed on raw and steamed carrots and Brussels sprout for comparison. Sous-vide carrots were firmer than steamed and firmness increased during storage. Similar values of colour indices were obtained for both steamed and sous-vide carrots, which also showed an increase of redness and colour saturation during storage. Aerobic and anaerobic counts of raw carrots were significantly reduced both by steaming and sous-vide procedures at values lower than 1 log cfu/g; these values were maintained until the end of storage. Among volatiles, terpenes were better preserved in sous-vide than steamed carrots, but all volatile fractions were significantly affected during storage. Steamed Brussels sprouts were softer and greener than sous-vide-processed ones, but softening and loss of green of the latter increased under vacuum storage. Microbiological counts of raw products were more efficiently reduced by sous-vide procedures than steaming. Higher amounts of nitriles and terpenes were shown in sous-vide vegetables in comparison to steamed, whereas thiocyanates and isothiocyanates occurred in lower quantities. Volatiles were not affected during 5 days of storage.