Abstract: Freezing and thawing are two necessary steps in the traditional consumption of ‘ruan’er’ pear and ethrel is widely used in the acceleration of climacteric fruit ripening. Aromatic components change investigation of ‘ruan’er’ pear at its two ripening points, after 1 wk freezing and two scheme thawings was conducted by the headspace-solid phase micro extraction-gas chromatography-mass spectrum test in combination with principle components analysis (PCA). In total 84 volatile compounds were detected with the predominance order of esters (42), alcohols (19), aldehydes ( 5), acids (5) and ketones (4). The PCA showed that ethrel treatment and cool water thawing elevate volatile compounds production and thus are beneficial to the fruit flavor quality; although the fruit keeps elementary common aroma components through the investigated time span, some technical-point specific volatile compounds occur in fruit they change its aroma.

Key words: climacteric fruit, thawing schemes, freezing, volatile compounds, principle components analysis