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Volatile esters contribute important floral and fruity sensory properties to wine. Numerous factors influence the biosynthesis and hydrolysis of esters throughout fermentation. In this study, the effect of yeast inoculation levels in Chardonnay juice fermentations was investigated. Ester formations were monitored by solid phase microextraction (SPME) during alcoholic fermentations of Chardonnay juice. Repeated batch fermentations were conducted with different inoculation levels (0.25g dry yeast/? and 0.5g dry yeast/?). Concentrations of ethyl acetate, ethyl butyrate, isoamyl acetate, ethyl hexanoate, hexyl acetate, ethyl octanoate, and ethyl decanoate after fermentation were significantly higher in high inoculation level fermentation (0.5g dry yeast/?) than an low inoculation level fermentation (0.25g dry yeast/?) (t-test, p＜0.001). Fermentation progress showed similar profiles in all fermentations. However, yeast cells with low inoculation levels showed longer activity than those with the other fermentation levels.
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