Effects of water activity, leucine and thiamine on production of aroma compounds by Ceratocystis fimbriata

Abstract

Ceratocystis fimbriata was grown in a standard liquid medium to determine the production of aroma compounds as affected by thiamine addition to the inoculum, thiamine or leucine addition to the medium, and the effect of water availability. Ethanol constituted more than half of the total volatiles production in the headspace, followed by ethyl acetate (22.6%), ethyl butyrate (10.8%), isobutanol (7.6%), amyl alcohol (1.6%), isoamyl acetate (1.5%), acetaldehyde (1.2%), ethyl propionate (0.9%), isobutyl acetate (0.4%), diacetyl (0.6%) and isoamyl alcohol (0.3%). Although significant two-way interactions were observed (P < 0.05), production of volatile compounds tended to be higher in inocula prepared with thiamine (T+) than in inocula without thiamine (T−), and in the standard medium with thiamine (SMT) as compared to the standard medium alone (SM) and the SM with leucine (SML). Also, the reduction of water activity (a w) resulted in lower quantities of volatiles being produced.