Effect of drying treatment conditions on sensory profile of germinated oat

Germination and subsequent drying of oat produced significantly different s ensory profiles depending on processing parameters such as drying speed and temperature profile. The most salient sensory attributes for processed oat were roasted odor and flavor, sweet taste, intense odor, intense aftertast e, and hard, crisp, brittle texture (P < 0.05). High temperatures (>85 degr eesC) were necessary to produce these sensory attributes, and quick drying after germination resulted in higher levels of intensity of favorable senso ry attributes. The total amount of volatile compounds was higher in native (ungerminated) oat than in processed oat. During germination, and particula rly during the drying treatment, the profile of volatile compounds changed. The most abundant volatile compounds responsible for odor were dimethyl su lfide, hexanal, pentanal, and isobutanal. The relative amount of dimethyl s ulfide increased as a function of temperature in drying, whereas hexanal, p entanal, and isobutanal disappeared during heating, as did several other sm all ketones, alcohols, and esters. The germinated oat dried at high tempera tures (65-93 degreesC and 65-85 degreesC) was perceived as being roasted, s weet, and nutty. Sensory and instrumental profile analyses of selected vola tile compounds using partial least squares (PLS) regression techniques show ed that these sensory attributes were clearly related to dimethyl sulfides and isobutanol. A moist and earthy odor was related to cymene, limonene, an d isobutanal. Phenolic compounds significantly influenced oat flavor, where as lipids had a negligible effect.