Effect of adulteration versus storage on volatiles in unifloral honeys from different floral sources and locations.

High fructose corn syrup (HFCS) was added at 5% to 40% to Indiana wildflower honey and added at 40% to Ohio and Indiana honeys from blueberry, star thistle, clover and wildflower, and an unknown source to simulate honey adulteration. Unadulterated honeys were also stored at 37 ºC from 1 to 6 mo. The volatile composition was measured by Selected Ion Flow Tube Mass Spectrometry (SIFT-MS). Most volatiles decreased in concentration with both increasing HFCS and storage time. Furfural significantly increased in concentration in all adulterated honeys and 1,3-butanediol, acetonitrile, and heptane in some adulterated honeys. During storage, the volatiles that increased were maltol, furfural, 5-methylfurfural, and 5-hydroxymethyl furfural in all honeys and also acetic acid and 1-octen-3-ol levels in some honeys. Soft independent modeling by class analogy (SIMCA) was used to differentiate the volatile profiles of adulterated honeys from fresh and stored honeys. The volatile profiles of honeys in accelerated storage for up to 4 mo and the honeys adulterated with 40% HFCS were significantly different. Acetic acid had the most discriminating power in Ohio star thistle and blueberry honeys and unknown honey while furfural had the greatest discriminating power in Indiana blueberry, star thistle, and clover honeys. Adulteration and storage of honey both reduced the volatile levels, but since they changed the volatile composition of the fresh honey differently, SIMCA was able to differentiate adulteration from storage.

CONCLUSIONS

Analysis of adulterated and stored honeys determined that both decrease volatile levels, and no clear indicator volatiles were found. However, SIMCA can be used to distinguish the volatile profiles of fresh or stored honeys, from adulterated honeys.