What is stone grinding?

Stone grinding is the most ancient method for grinding grain and the best system for producing high-quality flours.


How is stone grinding carried out?

The stone grinder is formed of a cylinder around the two millstones, covered with wood on the outside and with internal steel walls. The grain is poured through a funnel-shaped aperture, called a hopper, which is positioned above the cylinder and contains the grains. The stones inside are circular and the hardness and porosity varies according to the type of cereal to be ground.

The side on which the stones rub against each other is grooved and hammered. The grooves serve to channel the flour and the hammered part serves for grinding.
The stones are subject to slow but inevitable wear, so they are periodically hammered. This is the technique used to sharpen the millstones.

The distance between the two stones is adjusted by means of a large screw. It is tightened to move the stones closer together and loosened to move them further apart.
This is the operation that establishes the correct milling, or an even and fine particle size.

Quale è la pietra migliore per la macinazione a pietra?

The right stone for grinding must be harder than granite, as a soft stone would end up crumbling into the final product. It would also become thinner and overheat the flour.
Both natural stones and artificial agglomerates exist. Here at Molino Agostini, we have decided to use only natural stones.
The best stones are French and we have three different types, one for each type of cereal.


Macinazione a Pietra - Molino Agostini


Why is stone grinding better?

One of the main advantages of this type of grinding is the low speed of the wheel. In the milling phase, it crushes the grains at a speed that maintains a constant temperature of the flour, preventing it from overheating and thus losing the beneficial properties of this type of flour.

This is why stone grinding of grain guarantees better nutritional and organoleptic properties than cylinder grinding.

This type of grinding is recommended because it preserves the vitamins, mineral salts, fibre, noble proteins and enzymes of the cereal, which makes it easier to digest and more nourishing.
The more refined products our body absorbs, the higher will be the quantity of insulin the body must produce. Insulin causes fat to deposit and can cause diabetes, headaches, fatigue, allergies and other illnesses in predisposed people.


Macinazione a Pietra - Molino Agostini


Is stoneground flour also whole grain flour?

In traditional stone milling, the yield is usually lower than for cylinder grinding and the degree of refining cannot be excessive in this type of processing. It is the best method for producing whole grain or semi whole grain flours, since it preserves the wheat germ.

In contrast with cylinder grinding, the grain is ground dry with this type of grinding, or with its natural humidity or a lower than usual percentage of humidity, otherwise something called kneading occurs.

After years of sacrifice, these three stone grinders, each used for a different grain, are a dream come true.


Macinazione a Pietra - Molino Agostini