Cryogenic grinding for better aroma retention and improved quality of Indian spices and herbs: A review

Spices are very well‐known for their characteristic aroma and peculiar taste from ancient time. Grinding of spices is an old practice using different grinding equipment suited as per prevailing conditions. In modern era, the popularity of quality processed products has increased in spices. Cryogenics has very important role to play in food sector. Liquid nitrogen is the preferred among all available cryogens to obtain desired low temperature in food grinding. Grinding of spices at very low temperature produced superior quality ground powder with better hygiene. In spite of a proven technology it is not being popular in developing countries including India due to high initial investment. Present review article brings together the original work done to realize physico‐mechanical, thermal and grinding characteristics, aroma profile, and medicinally important compounds of selected spices for developing design of low cost cryo‐grinder specifically for spices and its possible commercial application. Practical applications Cryogenic grinding of spices and herbs not only retain the volatiles with no loss as well as maintain the originality in flavor quality, thus has prospective commercial uses. Enhancement of pharmacological properties opens another important avenue for utilization of this technology for herbal grinding in Ayurveda and other traditional system of medicine. Particle size up to 50 μm may be achieved by cryogenic grinding which in turn will be more effective in medicinal or therapeutic use. Less quantity of herbal drugs will be required if ground cryogenically.