For traders, millers, feed producers, and any professional using wheat in their supply chain, understanding grain classes is fundamental to product quality. In this article, we explain in simple terms what wheat class means, which quality indicators really matter, and how to avoid mistakes when selecting a batch based on the current GOST 9353-2016 standard.

What is a wheat class?

In short, a class is a universal "passport" for a commercial batch of grain. It allows buyers and sellers to quickly assess the product’s value without having to run complex laboratory tests for every transaction.


Since 2018, Russia has operated under the interstate standard GOST 9353-2016 "Wheat. Technical Specifications." As experts from VNIIZ (the All-Russian Scientific Research Institute of Grain) explain, this standard represents a **commodity classification**. It is designed to evaluate grain as a tradeable asset and facilitate financial settlements between suppliers and consumers. Its key difference from previous standards is the removal of strict guidelines regarding the end-use purpose of each class.


The class of each grain batch is determined by the lowest value of any one quality indicator.

Wheat types: difference between classes

Before looking at numbers, it’s important to know that wheat varies not only in quality but also by its biological "type." GOST divides wheat into 6 types based on the botanical species (soft or hard), biological form (winter or spring), and grain color:

• Type I - Spring soft red wheat
• Type II - Spring soft white wheat
• Type III - Winter soft red wheat
• Type IV - Winter soft white wheat
• Type V - Spring durum (hard) wheat
• Type VI - Winter durum (hard) wheat

Each type possesses different properties that are crucial for various processing methods.

Wheat Class System

The standard categorizes wheat into classes based on its quality:

• Class 1 and 2 (Strong Wheat): The quality benchmark. Used as a "strengthener" for weak flour. Characterized by high protein and gluten content.
• Class 3 (Valuable Wheat): The backbone of the baking industry. Used to produce mainstream bread varieties.
• Class 4 (Filler / Weak Wheat): Low gluten content. Unsuitable for bread-making without the addition of strong wheat from Classes 1 or 2.
• Class 5 (Feed Grain): Used for animal feed and compound feed production.

Key Quality Indicators

Because the class is set by the poorest-performing indicator, even a batch that looks and smells perfect can be downgraded by a single bad test result. GOST standards highlight the following critical parameters:

1. Protein Content

The mass fraction of protein in dry matter is a key indicator. The higher the protein percentage, the higher the potential wheat class.

2. Gluten Quantity and Quality

Gluten (a complex of protein substances) determines the baking properties of flour. Gluten quality is assessed using the GDI (Gluten Deformation Index), as well as mass fraction of gluten and gluten quality group.
Mass fraction of gluten, % min:

• Top Class - 36.0
• Class 1 - 32.0
• Class 2 - 28.0
• Class 3 - 23.0
• Class 4 - 18.0
• Class 5 - not limited

Gluten quality group, not lower than:

• Top, Class 1, Class 2 — Group I
• Class 3, Class 4 — Group II
• Class 5 — not limited

3. Falling Number

This indicator reflects the activity of the alpha-amylase enzyme. A low falling number indicates grain sprouting and a deterioration in baking properties.

• Top, Class 1, Class 2: more than 200 seconds
• Class 3: 200-151 seconds
• Class 4: 150-80 seconds
• Class 5: less than 80 seconds

4. Vitreousness

A parameter of endosperm consistency. Vitreous grain has a strong bond between starch and protein, ensuring a higher flour yield during milling. For Top, Class 1, and Class 2, vitreousness must be at least 60%. There are no restrictions for Classes 3, 4, and 5 regarding this indicator.


When choosing wheat, don't look only at the price and the class. Grainrus provides a Certificate of Quality and Safety for every batch of wheat and other products, including a detailed grain analysis of each of these key parameters.

Sources

1. All-Russian Scientific Research Institute of Grain and its Processing Products (VNIIZ). "On the new standard for wheat grain."
2. GARANT Information and Legal Support. "Classification of procured and supplied wheat by class" (based on GOST R 52554-2006).
3. Rosselkhoznadzor (Federal Service for Veterinary and Phytosanitary Surveillance). "Wheat Class."
4. GOST 9353-2016. Wheat. Current Standard.