Innovative high power short time microwave finish drying cum decontamination method for producing hot curry spice mix (Garam Masala) with enhanced quality characteristics

Abstract

Garam Masala is a mixture of ground spices commonly used in Indian and some Asian cuisines. Garam Masala risks microbial contamination due to poor hygienic conditions during various stages, including harvesting, processing, and storage. Moreover, its phytochemicals and antioxidant capacity need to be enhanced for better application in curry preparation and other recipes. The Garam Masala generally has a high microbial load and relatively higher moisture content (10-12% wet basis). The product having such a high moisture content is not shelf stable for longer durations due to its vulnerability to microbial growth. Therefore, an innovative high power short time finish drying cum decontamination method using microwaves (2.45 GHz) for Garam Masala was developed. Garam Masala was subjected to three different levels of microwave power density (10, 15, and 20 W/g) for 60 s. The best microbial load treatment protocol was also implemented, which consisted of applying 20 W/g for a duration of 60 s, followed by 6 cycles of 10 s “ON” and 5 s “OFF”. Drying kinetics were studied, and the Page model was found to be the best-fitting model. Microwave treatment exhibited a significant (p < 0.05) reduction in the total aerobic mesophilic bacterial count (2.79 log) and Bacillus cereus (1.83 log). The results also demonstrated that 15 W/g treatment enhanced the total phenolics, flavonoids content, and antioxidant capacity. No significant color changes were found between the untreated and treated samples. Therefore, it was concluded that a high power short time microwave finish drying cum decontamination method can control the microbial load and enhance the chemical characteristics in Garam Masala.