Physicochemical properties of cherry tomato dried using the conventional hot air (HA) and superheated steam (SHS) combined with either HA or far-infrared (FIR) were measured to evaluate the effects of combined drying process on the product quality. Conventional HA drying caused the greater extent of water removal than that of SHS combined with HA or FIR due to comparatively its longer drying time, resulting the lower water activity. Total acidity of cherry tomato produced by combined drying processes was slightly lower than that of conventional HA drying. Application of SHS combined with FIR resulted in higher retention of vitamin C and lycopene content with faster rehydration capacity than those of both conventional HA and SHS with HA drying. These results suggested that SHS combined with FIR would replace the conventional HA drying process successfully in production of dried cherry tomato with appropriate quality characteristics

Physicochemical properties of buckwheat roasted at specified temperatures (175, 200, 225 and 250°C) and times (5 and 10 min) were investigated. Appearance of roasted buckwheat showed that non-enzymatic browning reaction occurred mainly at the embryo due to the presence of sugars and proteins. Microstructure of roasted buckwheat showed the formation of air cells inside the endosperm indicating the expansion of grain during roasting. Rapid Visco Analyzer profiles revealed that the extent of starch gelatinization was depending preferentially upon the roasting time rather than temperature. Total polyphenol and flavonoid content in roasted buckwheat were not significantly different from those of unroasted grains, although polyphenols and flavonoids in ethanol extracts increased slightly after roasting. Antioxidant activities of buckwheat increased after roasting.