This amazing machine is a perfect kitchen accessory that helps to prepare the batter for making Idlis, Dosas, Vadas, Dhoklas etc. A lot of people use a mixer/grinder for the same purpose. But the advantage of using a wet grinder is that the heating or overheating that occurs during the mixer/blender operation tends to heat up the ingredients and sometimes imparts a slightly different taste to the batter unlike the wet grinder that does stone grinding. Hence in a way the grinding in a wet grinder preserves the micronutrients of the batter.

Manual Stone Grinders:
This machine has drastically reduced the hard work that had to be done in the earlier days by women using a manual stone grinding apparatus. This required a lot of energy, stamina and time, as small quantities of the ingredients used to be ground.

Since these grinders were made of large stones they were always placed on the ground either in a kitchen corner or in a kitchen yard. The grinding was achieved by using a cylindrical stone with either a wooden handle at the top or a slightly tapered top portion. This was rotated by hand by a person in a squatting position in a circular motion inside a slightly deep hole present in the centre of a solid stone base, shaped like a large bowl but having a flat surface on the top with a raised rim all along the outer diameter. Small quantities of water had to be added from time to time to reduce the friction and aid smoother grinding. Traditionalists believe that the quality of batter and hence the taste, and quality of the Idlis, Dosas, etc that were made with this kind of grinding was far superior to any other kind.

Manual stone grinders
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Different types of Wet Grinders
The mechanised wet grinders are available in two types–table top type, and tilting type.

Table top type wet grinder:

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Features of Table Top Wet Grinders
These grinders are portable and designed to be mounted on a table top. They are designed to provide continuous and trouble free service and for easy cleaning and maintenance. These wet grinders are used for a wide variety of wet grinding applications, yielding a batter that forms the base for delicious preparations like idli, dosa, vada and lot more. These can be also used for pulping vegetables for soups, for grinding semisolid masalas and chutneys.

These have the highest motor rating in this class of grinders in the market. This prevents the motor from overheating even under long and heavy use. They are available in varying capacities of 1.25 ltrs to 2 ltrs for domestic use.

They are also designed to have impact resistant bodies.

The grinder stone is made of hard black, good quality, granite that ensures no chipping or powdering during wet and dry grinding applications. The plastic components used are made of food grade nylon.

The rotation of the grinder stone in this equipment is maintained at a moderate speed to avoid heating of the ground paste thereby retaining the micro-nutrients in the food. This helps in longer shelf-life of food unlike other high speed rotating appliances, where the heat generation affects the taste as well as the micro-nutrients in the food.

The roller stones crushes, mixes, pounds and grinds simultaneously, so that all the ingredients  are ground to exact proportions and are thoroughly mixed, retaining  the nutrition value and also the desired taste.

Tilting Type Wet Grinder:

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The steel drum and stone grinder assembly
 
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Features of the Tilting Type Wet Grinder
The most important feature of this type of grinder is its space saving ability. In this type of wet grinder roller stones are used for efficient and smooth grinding hence they make very less noise while operating.

Powerful and energy efficient motors are required in these types of wet grinders.

The parts which do the grinding are in a steel drum. Two roller stones are connected with each other through a plastic rod in-between and they can be removed for the purposes of cleaning.A titling feature in these types makes it unnecessary to have to lift the vessel or drum to pour out the batter. Thus cleaning is easy by simply pouring in water, running the grinder for a few seconds and pouring out the water; it almost cleans itself.

This can be used to grind coarse dry powders too, along with the usual wet grinding abilities.
Usually stainless steel is the material used for the stand as well as the grinding drum for strength and durability. The motor housing is usually made of plastic. The grinder stone is made of hard black, good quality, granite that ensures no chipping or powdering during wet and dry grinding applications. The plastic components used are made of food grade nylon.