Grinding is a technique which reduces the size of spices considerably increasing the surface area available to impart flavour to any prepared food. Unfortunately, a substantial amount of flavouring components is lost due to the increase in temperaturewhile using conventional grinding methods. The cryogenic process actually embrittle a solid food material prior to size reduction and controls heat build-up in the grinding equipment and retain the flavour components of the materials. Cryo-grinding involves cooling a material below its embitter-ment temperature with a cryogenic fluid. After cooling, the material is fed into an impact mill where it is reduced in size primarily by brittle fracture. Liquid nitrogen (LN_2) or carbon dioxide (C0_2) can acta rescuer for retention of quality by reducing the temperature of the food material as well as grinder substantially. Cryogenic grinding permits to grind fibrous, elastic, heat-sensitive and thermoplastic materials economically to very small fine particle sizes. Experimental analysis reveals that the loss of volatile components and particle size distribution of the ground spices are more than the satisfaction level of the processor.
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