What is Cold Pressed
The true form and as per Vedic definition, Cold-Pressed Atta should have 2 qualities.
First, it should be crushed in Natural Stone. Natural stone is the same stone that is used in
traditional hand Chakki’s used by our forefathers. Second, it should be made at low speed
which means it must come out cold when grinding is done.
Slower the better
Stone milling is relatively a slow tedious process, often processing with less quantity of wheat
per hour. Since stone milling is a relatively cool process compared to high-speed rollers, processing
of wheat continuously, which heat up the four significantly killing most of the vitamins.
What are the Differences Between Stone (Chakki) Milling & Roller Milling of Wheat Flour (Atta)?
Traditionally, Indian wheat flour (atta) is grounded in stone mills known as Chakkis. It consists of a pair of round stones. One stone is stationary, while the other rotates over the first along a common axis. As a result, the flour is very finely milled. It consists of the nutritious parts of wheat grain i.e. bran, germ and the endosperm in original proportions.
However, in roller milling, the wheat flour produced is very fine. But, in refined wheat flour, the bran and germ does not exist. It only consists of the endosperm part of wheat grain. In fact, the bran is added back to the final product.
Stone (Chakki) Milling
Chakki atta is grounded in stone mills known as chakkis. It consists of pair of round stones. One is stationary; the other is a rotating stone. It is relatively a slow tedious process.
It is preferred for its texture and taste. In fact, chakki atta is rich in dietary fiber and vitamin B which is good for metabolism.
Stone grounded flour is processed at 40 to 60 degrees Celsius. The operator continuously smells the air to check the stones are not getting too hot.
Commercial Roller Milling
Commercial roller mills operate at much higher speed. They process tons of wheat simultaneously. As a result the flour heats up significantly destroying most of nutrients.
Heat generated due to friction in stone mills causes Starch Damage. Starch damage significantly increases water absorption and the dough mixing properties.
Rolling mills can have temperature up to 90 degrees. 60 degrees and above milling temperature completely destroy vitamins in the flour.