Influence of the time/temperature binomial on the hydroxymethylfurfural content of floral honeys subjected to heat treatment

Abstract

Hydroxymethylfurfural (HMF) content is internationally recognized for its ability to indicate the freshness or lack of freshness of honey and can be used to judge the processing and storage condition of honey. The objective of the present study was to evaluate the evolution of HMF levels in fresh extracted honeys submitted to different temperatures ranging from 30 to 100º C, during pre-established time intervals (30, 45, 60, 180 and 720 minutes).The test was conducted in floral honey with an initial HMF content of 2.2 mg/Kg. The maximum value recommended by the Brazilian law (60 mg/Kg) was not exceeded in the samples subjected to heating for 30, 45 and 60 minutes regardless of the temperatures used. When the samples were heat treated during 180 minutes at 90º C the official value was surpassed. The highest values were observed in samples subjected to heating over 720 minutes, and the limit was exceeded at 70º C. The results obtained indicate that the HMF content gradually increases when the honey is heated at high temperatures for long periods. Therefore, we suggest a process optimization, considering the initial HMF content of the product and standardizing times and temperatures to ensure a good quality of the final product.