Natural flint mill stones : the history of a technique

Milling: an age-old tradition

Although flour has existed since the dawn of time, originally crushed by hand using a mortar, it was the invention of the wheel and the system of millstones rotating above a fixed stone that led to the development of new techniques. These millstones have been used since Neolithic times, but the processes have improved over the centuries: from horse-drawn millstones to millstones powered by water or wind, right up to the advent of electricity. Today, very few mills still have millstones, most having been industrialised in the 19th century to produce cylinder-ground flour.

Our Boussay mill has chosen to perpetuate the traditional techniques of using millstones. It is a choice dictated by the stones’ formidable ability to mill ancient wheats and produce exceptional flour. Today, we have the largest stock of natural flint millstones in Europe (22 pairs), which would be impossible to maintain without passing on this historic expertise.

From wheat grain to flour

Originally, the miller’s job was simply to crush the wheat grains. He would then deliver them to households and bakers, who sifted them themselves to separate the flour from the bran if necessary. Then millers began to take care of all the processing, including any blending. These processes require real expertise, as there are so many stages and they have to be repeated as many times as necessary to complete the result expected by the customer.

What is a millstone? 

A millstone mill uses pairs of stone wheels, one rotating and one fixed. The millstones are cylindrical in shape, with a large diameter but low height. The fixed (lower) one is called the “dormant” stone, and the rotating (upper) one is called the “flying” stone. Both are enclosed in a protective casing.

The rotating millstone passes over the cereal grains to crush them and release the flour they contain. Our pairs of grinding millstones can weigh up to 1 ton.

Millstones: which process?

This was the first milling process ever invented. Depending on the wheat selected and the flour required, around fifteen operations are necessary. Only the miller masters the process: cleaning, grinding, splitting, converting, sieving, storing and bagging.

Even if the yield is lower than with cylinder milling (which separates the germ from the kernel), with this technique the grain retains its essential nutrients and components. The grain is crushed in its entirety between the millstones, retaining all the vitamins and minerals contained in the germ. All the substances released in this way are mixed into the flour obtained.

Our milling expertise at the heart of a modern mill

The technique of crushing the grains is an unrivalled skill that combines the best of the most modern traditions and techniques. Our Organic Boussay Mill uses the ancestral principle of grinding, while concentrating cutting-edge innovations. The expertise and knowledge of our millers are still essential to find the right settings and obtain quality flours from millstones.

Minoterie Suire represents the transmission, from generation to generation, of milling expertise combined with a modern approach. We are recognised both in France and internationally for the quality of our organic flours ground on these millstones.

Our millstones : the choice of flint

Why did we choose flint? All types of stone have been used over the centuries: granite in the Jura and Brittany, sandstone in the Haute-Loire, Germany and the UK, and limestone in Anjou and Aquitaine. Millers were quick to realise the importance of the stone type when determining the quality of stone-milled flour. Most had major faults: dust and odour in limestone, abrasion in sandstone, wear with granite, etc.

If the stone is too soft and crumbles, the flour will be full of stony particles and the stone will wear away quickly. On the other hand, a stone that is too hard will polish with use and the grains will slide too easily across the surface.

The most suitable natural stone is undoubtedly flint. More specifically, quartz (known as millstone flint). This is Minoterie Suire’s choice: a rock produced by the accumulation of the siliceous skeletons of micro-organisms and/or complex chemical reactions. It is made up of pure chalcedony and impurities such as water or oxides, which affect its colour.

Although flint crumbles much more slowly than granite, it does wear down. And flint quarries no longer exist. That is why we’re always on the lookout for unused millstones to restore and reintroduce to our mill.

Building flint millstones : the expertise of the miller

The quality of the flour depends on the miller’s expertise when building his millstones, before any processing takes place. They are made up of a combination of flint stones and tiles, assembled in equal batches of hardness and spread over the entire surface. The millstone ensemble contains several concentric parts, with the hardest stones used at the edges. Once the casing tiles have been cemented together, the miller can proceed to make the surround, shaping the tiles to fit the existing parts. The millstone is held in place by two flat iron rings.

The grain that falls into the eyelet (the opening in the centre of the stone) must fit easily between the two millstones. There must be sufficient clearance in the centre. Once ground, the grain decreases in volume and the millstones must then move towards each other.

The whole process is fine-tuned in line with local traditions and the types of flour our customers want: wheat, spelt, buckwheat, etc.

Maintaining and cutting millstones : a real art

Our millers have a real historical expertise when it comes to maintaining their work tools. A good mill means preserving the components of the millstones, which must remain at optimum efficiency. Millers have to carry out regular operations that require special tools and techniques:

  • The rotating millstone must be perfectly balanced, both when stationary and when operational.
  • The entrance to the millstone must be kept clear so that the grains can always pass through.
  • The surface of the millstone should be perfectly flat.
  • As for the spokes, they must always be at a depth of around 6mm, and so on.

These are all points that can only be mastered by our expert millers.

Our iconic recipes

Tourte aux Alouettes

Alouettes are skylarks. They are becoming rare…we don’t hear their song that often any more! Pesticides have been introduced and, unfortunately, these birds have deserted our fields. Our recipe for Tourte aux Alouettes bread is a real nod to our commitment to protecting the environment.

Made from the seeds ‘pecked’ by skylarks after the harvest, and a blend of wheat, spelt and rye flour and starter, Fabrice Guéry has created a bread with a distinctive, crisp golden crust.

This local bread is a tribute to our region, and showcases the technical expertise and historic savoir-faire of our natural flint millstones.

La Tourte de Meule Bio

This rustic bread is very filling and is made from T80 organic wheat flour, which retains the best of the fibre, B vitamins and minerals in the wheat grain, germ and bran. With its slightly malty notes and golden, tight, soft crumb, Tourte de Meule is ideal as a sandwich, or as an accompaniment to dishes with sauce.

Tourte de Seigle Bio

This organic bread is made with T130 organic rye flour and rye starter, which brings out the honey notes in the rye and gives this bread a distinctive flavour. Our Tourte de Seigle bread, which our bakery customers love, has a tight, supple crumb. We recommend it for its fibre content, and as an accompaniment to seafood or good local cheeses.