Investigation of the effect of lemon juice concentrate added to different honeys on HMF formation

In this study, it was aimed to examine the changes in the physical and chemical properties of honey during the initial and storage period by adding lemon juice concentrate to pine, flower and chestnut honeys. In this context, by adding 0%, 1%, 2% and 3% lemon juice concentrate into pine, flower and chestnut honeys, water soluble dry matter (brix), pH, free acidity, reducing sugar, total sugar, sucrose, total phenolic substance amount, antioxidant capacity and HMF analyzes were made. In addition, pine, flower and chestnut honeys in which 0%, 1%, 2% and 3% lemon juice concentrate was added were stored at 25℃, 35℃ and 45℃ for 6 months. Total phenolic content, antioxidant capacity and HMF levels of honeys were monitored at 0, 3 and 6 months. Average water-soluble dry matter (brix) values of honey samples were determined in the range of 78.83-82.00%. Average pH values were found in the range of 3.00-4.46. Average free acidity values were found to be 8.48-72.26 meq/kg. Average total phenolic content values were determined in the range of 4.14-218.70 mg GAE/100 g. Average antioxidant capacity values were determined at the level of 1.01-16.09 mg GAE/100 g. Average reducing sugar values were found in the range of 87.47-105.08%. Average total sugar values were measured as 93.72-111.10%. Average sucrose values were determined as 4.02-7.68 g/100 g. Average HMF levels were determined as 12.41-7646.46 mg/kg. During storage, the total phenolic substance level increases with time at all three storage temperatures. A generally significant positive correlation was found between antioxidant capacity and total phenolic substance level. In this study, HMF values increased over time at all three temperatures, as expected. However, depending on the amount of lemon juice concentrate added, HMF levels increased dramatically during storage. In this study, it has been revealed that the analysis results of the three types of honey used are in compliance with the Turkish Food Codex Honey Communiqué. The results obtained after the study show parallelism with the hypotheses determined. It has been observed that lemon concentrate, which is used to increase the nutritional and functional properties of ready-made honey preparations, can accelerate the formation of unwanted reaction products during storage.