Wet grinder

A wet grinder can refer to either a tool for abrasive cutting of hard materials, or a food preparation appliance used especially in Indian cuisine for grinding food grains to produce a paste or batter. A wet grinder for abrasive cutting uses fluid for lubrication or cooling, whereas one for food preparation uses water to combine with ground grain to produce batter.

Some angle grinders, most tile saws, and some grinders for sharpening blades used in woodworking are wet grinders. The fluid helps with lubrication of the cutting process and with cooling to avoid cracking or damaging the cutting tool or the workpiece.

Wet grinding is rare in western cuisine but common in Indian cuisine. Wet grinders are used to make pastes from grains and lentils, such as those used in cooking dosas and idlis in South Indian cuisine. These grinders generally consists of a few granite stone plates that are rolled against another stone plate with the items to be ground between them. Wet grinders have two advantages over electric mixers or blenders. First, the stone grinder generates less heat than a mixer; heat affects the flavor of the food. Second, the stones remain sharp for a greater time than do metal blades.

Wet grinders are largely manufactured in Coimbatore because granite is easily available in this region. Beginning in March 2006, the label "Coimbatore Wet Grinder" is a registered geographical indication for Tamil Nadu.

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