HMF Monitoring: Storage Condition and Honey Quality

The present work reports the analysis and determination of 5-hydroxymethylfurfural (HMF) and furfural (FF) contents in 27 honey samples from different geographical regions in Brazil and the storage conditions of these honey samples. The study employed an adapted HPLC-DAD method which consisted of the addition of 2,5 furandicarboxylic acid (FDCA) as internal standard. With the aid of the multi-block chemometric tool ComDim, near-infrared (NIR) and middle-infrared (MIR) spectral analyses of the honey samples were carried out in order to study the regions that corresponded to the HMF and FF compounds. Small contents of HMF (< 36.92 mg kg) and FF (< 4.82 mg kg) were detected in honey samples collected directly from beehives. The contents of HMF found in honey samples of wildflower and soy flower origin collected from the São José Ocoí apiary were found to meet the defined conditions of freshness and quality as they presented HMF contents ≤ 10 mg kg. Commercial samples presented HMF contents ranging from non-detected to 157.34 mg kg and FF contents ranging from non-detected to 5.28 mg kg. Although the amount of FF concentration in honey is not regulated by law, the results obtained from Artemia salina and Lactuca sativa assays showed that this organic compound is much more toxic than HMF. The results obtained from the NIR chemometric-based technique applied showed that the honey samples with higher HMF concentration were identified by NIR absorption of functional groups that exhibited lower vibration in the following regions: 950–1100 nm and 1450–1600 nm.