Abstract
Despite the fact that honey is usually contaminated with numerous microorganisms, the number of contaminants is very low in comparison to other food stuffs. There is insufficient data to develop safety methods on a commercial scale for producing safe honey for use in food or medicine. The present work introduces a comparison between two common safety methods to choose the most beneficial option. Samples of high-quality honey were gathered from Saudi Arabia and Egypt and then treated separately with four doses of gamma-irradiation (5, 10, and 15 kGy) and two thermal treatments (60 degrees C and 90 degrees C). The effects on the samples were studied based on micro-biological features and antibacterial activity (AA). The parameters used to assess microbiological load included total bacteria count (TBC), total fungi count (TFC), and total spore count (TSC).
The results indicated that raw honey samples from Saudi Arabia naturally have low values for the examined microbiological characteristics. One Egyptian type exhibited a mildly increased microbiological load. No microbes were detected in only one Saudi Arabian type, i.e., Talh honey, while the Azhaar and Syder types had slight increases in the microbial load. Natural TBC levels were very low (1x10(3)), whereas the TFC was 4x10(2) (CFU/g) and the TSC was zero. For the Egyptian type, both highand low-temperature (60 degrees C and 90 degrees C) thermal treatment completely eliminated all microbes. In addition, only samples treated at high temperature had active antimicrobial compounds active against Gram-negative and Gram-positive [-(G) or +(G), respectively] bacteria, whereas samples treated with low temperature had active antimicrobial compounds only active against -(G) bacteria. Disadvantages of the thermal treatments included adverse effects on quality, destruction of antimicrobial compounds, loss of thermosensitive vitamins, and increased levels of toxic compounds. Irradiation at 10-15 kGy was more effective for decontamination, resulting in only slight changes to the honey, and this approach was more appropriate for maintaining quality after packaging. A preliminary measurement of the initial microbiological load in raw honey, which varies based on differences between different honey types, should be completed to deteimine the appropriate gamma-irradiation dose.