Identification and Biotransformation of Volatile Markers During the Early Stage of <i>Zygosaccharomyces rouxii</i> and <i>Zygosaccharomyces mellis</i> Contamination in Acacia Honey

To address the volatile markers and their biotransformation during the early stage of <i>Zygosaccharomyces spp.</i> contamination in acacia honey, headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) and chemometric analyses were used to explore the variation of volatile compounds. A total of 36 and 35 volatile compounds were identified before and after contamination of <i>Zygosaccharomyces rouxii</i> and <i>Zygosaccharomyces mellis</i>, respectively. Methyl butyrate and 2-methyl-3-pentanone could be used as volatile markers of <i>Z. rouxii</i> and <i>Z. mellis-</i>contaminated honey, which were both specific products of the yeast's own fermentation. 2,5-Dimethylbenzaldehyde was identified as a volatile marker of <i>Z. rouxii</i> and <i>Z. mellis-</i>contaminated acacia honey, and it was a specific product resulting from the interaction of yeast and acacia honey. In addition, β-damascenone could be determined as a potential volatile marker after <i>Z. rouxii-</i>contaminated acacia honey. Methyl 2-methylbutyrate was used as a potential volatile marker in the high-concentration groups of <i>Z. rouxii</i> and <i>Z. mellis</i>. The content ranges of methyl butyrate, 2-methyl-3-pentanone, and 2,5-dimethylbenzaldehyde in four samples were 6.62-14.59, 3.15-5.42, and 52.52-215.19 μg/mL, respectively. The variation of volatile markers during the early stage of osmotolerant yeast contamination provided a theoretical basis for the use of HS-SPME-GC-MS for the rapid detection of acacia honey deterioration while reducing economic losses.