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Quality reduction in honey during storage is indicated by hydroxymethylfurfural (HMF) accumulation and darkening of color. The effects of moisture content and temperature on HMF accumulation and color change in honey during storage were investigated. HMF accumulation and color change followed first‐ and zero‐order reaction kinetics, respectively. The moisture content affected the rate of the two degradation reactions depending on the storage temperature. Reduction in moisture content caused an increase in rate constant for HMF accumulation at 20 and 30C, but there was no significant effect of moisture content at 40C. Rate constants for change in lightness and total color change values increased with increasing moisture content at 20 and 30C. The highest rate constant for change in color values was obtained at a moisture content of 18% at 40C. PRACTICAL APPLICATIONS Hydroxymethylfurfural accumulation and color change are two major quality degradations in honey during storage. This study shows that the rates of these two degradations are dependent on moisture content of honey. In addition, effect of moisture content on the rates of reactions was dependent on temperature of storage. Therefore, producers need to consider the effects of both moisture content and storage temperature in reducing quality loss in honey during storage.

Conjugated alkyphenols in milk constitute a reservoir for species-related alkylphenols in dairy products. The distributions of conjugated alkylphenols between different conjugation pathways (sulfation, phosphorylation, and glucuronidation) were determined in cows', sheep's, and goats' milk. Species-related p- and m-cresols and 3- and 4-ethylphenols were found to be mostly conjugated with sulfate with minor amounts associated with phosphate and glucuronide conjugates in all milks. Similar distributions were observed for alkylphenols in the urine and milk from the same ewe. Phenol was present in minor amounts distributed sporadically between different conjugates in the milks. Sulfate-conjugated phenol was not detected in the ewe's urine, which included equal amounts of glucuronide and phosphate conjugates. The amounts of alkylphenols were different in sheep's milk from different sources suggesting that there were effects of feed, breed, and individual animal variation on the metabolism of alkylphenols.

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