Effect of ultrasound on the physical, biochemical, antioxidant, and antimicrobial properties of industrial Iranian honey

The aim of this study was to investigate the effects of ultrasound at two different frequencies, namely 30 kHz and 42 kHz, on various aspects of industrial Iranian honey, including its physical, biochemical, antioxidant and antimicrobial properties. Samples were subjected to ultrasound treatment at 30 kHz or 42 kHz for a duration of 1, 5 or 10 minutes at temperatures of 20 °C or 45 °C, respectively. The following parameters were then evaluated on days 1, 30, 90, and 180: HMF content, pH, acidity, proline concentration, total number of aerobic mesophilic bacteria, diastase activity, moisture content, sucrose concentration, fructose concentration, glucose concentration, fructose- glucose ratio, ABTS (antioxidant activity) content, number of osmophiles, phenol concentration, reducing sugar concentration and total sugar concentration. It is noteworthy that both treatment groups exposed to ultrasound showed changes in these parameters. Specifically, the group treated with ultrasound at a frequency of 42 kHz showed a decrease in moisture content, pH, acidity, fructosetoglucose ratio, total sugar concentration, clostridium count, total microbial count, mold count, osmophiles countand HMF content; as well as an increase in diastase activity, proline and phenol concentration. These changes were more pronounced on days 90 and 180. Ultrasound treatment at a frequency of 42 kHz for a duration of 10 minutes at a temperature of 45 °C has the potential to improve the quality and shelf life of industrial honey. Consequently, this technique can be used in the food industry to obtain a better product that is more suitable for export.