What is flour made of in the UK?

In the UK, about 85% of the flour consumed is milled from homegrown wheat. What flour is made of depends heavily on the specific grain and milling technique used, which dictates its properties, appearance, and nutritional content for various culinary applications.

Quick Summary

Flour in the UK is primarily milled from wheat, producing types like white, brown, and wholemeal flour through different milling processes. Fortification with specific nutrients is a legal requirement for most non-wholemeal flours to improve public health.

Key Points

• Primary Ingredient is Wheat: The majority of flour in the UK is milled from homegrown wheat.

• Milling Determines Type: The process of milling separates the wheat kernel's parts, and how they are reassembled dictates whether the flour is white, brown, or wholemeal.

• Fortification is Mandatory: All non-wholemeal wheat flour sold in the UK must be fortified with specific nutrients like calcium and iron as mandated by law.

• Plain Flour is Versatile: Plain flour, or all-purpose flour, has a medium gluten content and is best for baking where a raising agent is added separately.

• Gluten Levels Affect Baking: Flours with higher gluten content, like strong bread flour, are essential for products requiring a strong, elastic structure, while lower-gluten flours are better for softer goods.

• Other Grains are Available: Besides wheat, other grains such as rye, spelt, and maize are also milled into flour for specific culinary uses.

The Primary Ingredient: Wheat

In the UK, the vast majority of flour is made from wheat, with approximately 85% of it sourced from UK farms. A single wheat grain, or kernel, consists of three main parts: the starchy endosperm, the high-fibre bran, and the nutritious germ. The final type of flour produced is determined by which of these components are included after the milling process.

The Anatomy of a Wheat Kernel

• Endosperm: This is the largest part of the kernel and is rich in starch. White flour is made almost exclusively from the endosperm.
• Bran: The tough, outer layer of the kernel, the bran is packed with fibre. Wholemeal flour includes the bran, giving it its darker colour and coarser texture.
• Germ: The embryo of the wheat plant, the germ is rich in nutrients and oils. Wholemeal flour also retains the germ, contributing to its nutritional value and flavour.

How Wheat Becomes Flour: The Milling Process

Historically, flour was made using stone-ground mills, where the entire kernel was crushed between two large stones. While this traditional method still exists, modern roller milling is the standard for mass production in the UK today.

Roller Milling for White Flour

1. Cleaning & Conditioning: First, the wheat is cleaned of impurities and conditioned with moisture to prepare it for milling.
2. Break Rolls: The wheat kernels pass through a series of corrugated steel rollers that crack open the grains and separate the bran and germ from the endosperm.
3. Sieving & Purifying: A complex system of sieves and air currents separates the bran and germ from the starchy endosperm particles.
4. Reduction Rolls: The remaining endosperm particles are repeatedly passed through smooth rollers to grind them into fine white flour.

Modern Production of Wholemeal Flour

In modern roller mills, wholemeal flour is often created by separating the bran and germ from the endosperm during the initial milling stages, then blending them back in to achieve a 100% whole grain product. Traditional stone-ground methods, by contrast, grind the entire kernel at once, which can produce a slightly different texture and nutrient profile.

The Role of Fortification in UK Flour

Under the Bread and Flour Regulations 1998, UK law mandates that specific nutrients be added back into all white and brown wheat flour. This process, known as fortification, was introduced to address dietary deficiencies and includes the addition of:

• Calcium carbonate
• Iron
• Thiamin (Vitamin B1)
• Niacin (Vitamin B3)

Wholemeal flour is exempt from these regulations because it naturally contains these nutrients as the entire grain is used. Recent updates, such as the Bread and Flour (Amendment) (England) Regulations 2024, have confirmed increased levels of these nutrients and will legislate the addition of folic acid to help prevent neural tube defects.

Types of UK Flour Explained

Plain Flour

Also known as all-purpose flour, plain flour is a versatile, white flour milled from a blend of hard and soft wheat. It contains no raising agent, making it suitable for a wide range of uses, from thickening sauces to making pastries, biscuits, and cakes where a raising agent is added separately. It has a medium gluten content, offering a good balance for general cooking and baking.

Self-Raising Flour

This is essentially plain flour with raising agents, such as sodium bicarbonate and calcium phosphate, already added. This saves a baker the step of adding their own and is commonly used for light and fluffy cakes, scones, and sponges. The raising agents react when liquid is added to the flour, creating carbon dioxide that gives the bake its characteristic lift.

Strong White Bread Flour

Made from hard wheat varieties, strong white bread flour has a higher protein (and therefore gluten) content than plain flour. When kneaded, this gluten develops into a strong, elastic network that traps the gas produced by yeast, enabling bread to rise with a good structure and chewy texture. It is perfect for yeast-based recipes like loaves, rolls, and pizza dough.

Wholemeal Flour

Wholemeal flour contains the entire wheat grain—endosperm, bran, and germ—resulting in a darker, coarser, and more nutritious flour. It produces denser bakes with a nutty flavour and a high fibre content. To achieve a lighter wholemeal loaf, some bakers combine it with strong white flour.

Beyond Wheat: Other UK Flours

While wheat is dominant, the UK market offers a growing variety of non-wheat flours, including:

• Rye Flour: Produced from the rye grain, it offers a darker, denser texture and a distinct, tangy flavour.
• Spelt Flour: Milled from an ancient grain, spelt flour can be used as an alternative to wheat flour and is available in both white and wholemeal varieties.
• Cornflour: Derived from maize, this starch-based flour is primarily used as a thickening agent for sauces, gravies, and custards, rather than for baking.
• Gluten-Free Flours: A blend of different non-wheat flours, such as rice, potato, maize, and buckwheat, is used to cater to those with gluten intolerance.

Comparison of Common UK Flour Types

Feature	Plain Flour (White)	Self-Raising Flour (White)	Strong White Bread Flour
Composition	Milled wheat endosperm	Milled wheat endosperm + raising agents	Milled hard wheat endosperm
Protein Content	Medium (9-11%)	Medium (9-11%)	High (12-14%)
Best For	Pastries, biscuits, thickening sauces	Cakes, scones, muffins	Yeast breads, pizza dough
Raising Agent?	No	Yes	No (requires yeast)
Texture	Versatile, fine	Light, airy	Chewy, elastic

Conclusion

In the UK, flour is primarily made from wheat, though a range of other grains and plant sources are also used. The final product is heavily influenced by the milling process and the specific parts of the grain that are included. White and brown flours are legally fortified to boost nutritional value, a practice that defines the composition of many common supermarket staples. Understanding these differences, from the high gluten content of strong bread flour to the convenience of self-raising, empowers bakers to choose the right ingredient for their desired results. For more information on flour production, visit the UK Flour Millers website.

Frequently Asked Questions

What is the difference between British plain flour and American all-purpose flour?

While similar, British plain flour is typically milled from softer wheat and has a slightly lower protein and gluten content than American all-purpose flour, which is a blend of hard and soft wheat.

Is British white flour bleached?

No, UK law prohibits the use of flour bleaching agents like chlorine. Consequently, most white flour sold in the UK is unbleached.

Why is wholemeal flour not fortified in the UK?

Wholemeal flour is exempt from fortification requirements because it includes all parts of the wheat grain, meaning it naturally retains the required vitamins and minerals like iron and thiamin.

What is self-raising flour made of?

Self-raising flour is plain flour with a pre-mixed amount of chemical raising agents, such as baking powder and salt, included during the milling process.

Does flour in the UK contain any additives besides the statutory ones?

Some flour treatment agents, such as ascorbic acid (Vitamin C), may be added to bread flours to aid gluten development, but all additives must be declared on the ingredients list.

Can I use plain flour instead of self-raising flour?

Yes, you can substitute plain flour for self-raising flour by adding a raising agent like baking powder. As a general rule, add two teaspoons of baking powder per 150g of plain flour.

What is the UK equivalent of '00' flour?

While '00' flour is an Italian grade, it is readily available in the UK. It is a very finely ground wheat flour specifically used for making pasta and fine pizza bases.