Monitoring of the hydroxymethylfurfural amount as an indicator of Maillard products in sweet whey and skim milk powder stored under different conditions

Sweet whey powder (SWP) and skim milk powder (SMP) are widely used as food ingredients. These products are sensitive to Maillard reaction because of high sugar and protein content. Furfural products of the Mail lard reaction are used as specific indicators of the effects of heating treatments and storage conditions on SW P and SMP quality. Therefore, hydroxymethyl furfural (5-HMF) levels were measured in representative samples which were stored 8 months at three different temperatures (25, 35 and 45 degrees C) and moisture (2.5, 5,0, 7.5% for WPC and 5.5, 7.5, 10% for SMP) using Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) with DAD detection during storage period (8 months). The HMF contents ranged from 4.25 to 128.56 mg/kg and from 2.07 to 98.23 mg/kg in WPC and SMP, respectively. Although the HMF level of WPC increased with increasing moisture content, SMP samples reached the maximum quantity of HMF at 7.5%.