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Grain quality is a key factor that determines the success of grain exports. It directly affects the price, global market demand, and compliance with international contract requirements. To ensure objective assessment and fair pricing, the global grain industry follows clear standards that classify wheat and other crops. At the core of this system are the Gafta (Grain and Feed Trade Association) rules, which apply to most international contracts.
Quality Indicators That Determine Wheat Grain Class
Grain quality is a combination of physical and chemical characteristics, which can either be assessed visually or measured using specialised equipment and laboratory methods. Physical characteristics (such as colour and grain shape) can be determined by visual inspection, while chemical properties (such as protein content, moisture level, and gluten quantity) require laboratory analysis. The classification of wheat is based on specific quality indicators, which are strictly regulated by international standards.
Different wheat classes correspond to different quality levels and intended uses. The class assigned to wheat directly impacts its market price and attractiveness to importers.
Key quality indicators of grain include:
- Test Weight (Natural Weight). This indicator describes the weight of a specific volume of grain, essentially measuring how densely the grain is “packed” within a given space. The higher the test weight, the better the grain quality. It is measured in grams per litre (g/L) or kilograms per hectolitre (kg/hL). For example, bread-making wheat typically has a test weight of around 750 g/L (or 75 kg/hL).
- Protein. Determines the nutritional value of the grain and its technological properties. For bread-making wheat, protein content typically ranges from 10% to 14%.
- Moisture. The amount of water in the grain, which affects its storage stability. For wheat, the maximum allowable moisture content is usually set at 14.5%.
- Gluten. A key indicator of the grain’s ability to form dough, which is crucial for bread production.
- Damaged Grains (Broken Kernels or Damaged Kernels). The presence of damaged grains affects both the quality of the final product and the grain’s storability.
- Admixture. The percentage of foreign matter that is not wheat grain (e.g., plant residues, weed seeds, etc.). For bread-making wheat, admixture levels should not exceed 2%.
- Specific Quality Indicators for Certain Uses. For example, a key indicator for bread-making wheat is the Hagberg Falling Number, which assesses whether the grain has begun to germinate and how well it will perform in baking. This test measures the activity of the enzyme amylase, which breaks down starch into sugars, making the dough sticky and unsuitable for baking. The Hagberg Falling Number is measured in seconds and represents the time it takes for a plunger to sink under its own weight in a starch suspension. Lower values indicate higher enzyme activity, meaning poorer baking quality. In commercial contracts, a minimum of 220–250 seconds is typically required, though exact requirements depend on national standards and contractual agreements.
These indicators directly affect the classification of the grain and determine its market value.
Grain Quality Requirements
Grain quality requirements are determined by contract terms, international standards, and the legislation of the exporting country.
Typical criteria include:
- Moisture content, test weight, protein content, and gluten levels;
- Admixture content (including grain impurities and foreign matter);
- Compliance with a specific class based on physical and chemical characteristics.
The exact specifications depend on the type of grain, its intended use (bread-making, animal feed, pasta production, etc.) and the terms of delivery.
International Wheat Quality Classification
There is no single international wheat quality classification. Each country has its own standards and classification systems, which may be similar but are not unified. The specific classification applied is often specified in the contract.
Let us examine a few examples of wheat classification. While different countries use their own systems, it is important to understand the common elements in these classifications.
United States
In the United States, grain classification is regulated by the Federal Grain Inspection Service (FGIS). FGIS is a division of the United States Department of Agriculture (USDA) and is responsible for developing and implementing official grain standards. It ensures objective quality control through a network of accredited inspection agencies.
FGIS provides separate classifications for wheat, maize, barley, and other crops. For wheat, it defines five classes based on the following indicators:
- Test Weight
- Damaged Kernels
- Foreign Material (Admixture)
- Other Specific Defects (Contrasting Classes, Shrunken and Broken Kernels)
| Grading factors | Grades U.S. Nos. | 1 | 2 | 3 | 4 | 5 |
| Test weight per bushel | ||||||
| Hard Red Spring wheat or White Club wheat | 58.0 | 57.0 | 55.0 | 53.0 | 50.0 | |
| All other classes and subclasses | 60.0 | 58.0 | 56.0 | 54.0 | 51.0 | |
| Defects: | ||||||
| Damaged kernels (Total) | 2.0 | 4.0 | 7.0 | 10.0 | 15.0 | |
| – Heat damage (part of total) | 0.2 | 0.2 | 0.5 | 1.0 | 3.0 | |
| Foreign material | 0.4 | 0.7 | 1.3 | 3.0 | 5.0 | |
| Shrunken and broken kernels | 3.0 | 5.0 | 8.0 | 12.0 | 20.0 | |
| Wheat of other classes | 1.0 | 2.0 | 3.0 | 10.0 | 10.0 | |
| Stones | 0.1 | 0.1 | 0.1 | 0.1 | 0.1 | |
| Other material in one kilogram: | ||||||
| Animal filth | 1 | 1 | 1 | 1 | 1 | |
| Castor beans | 1 | 1 | 1 | 1 | 1 | |
| Crotalaria seeds | 2 | 2 | 2 | 2 | 2 | |
| Glass | 0 | 0 | 0 | 0 | 0 | |
| Stones | 3 | 3 | 3 | 3 | 3 | |
| Unknown foreign substances | 3 | 3 | 3 | 3 | 3 | |
| Insect-damaged kernels (in 100 g) | 31 | 31 | 31 | 31 | 31 |
Full information is available on the Federal Grain Inspection Service website.
Ukraine
In Ukraine, grain classification is regulated by state standards, which are developed and approved by the National Standardisation Body – State Enterprise “Ukrainian Scientific, Research and Training Centre for Standardisation, Certification and Quality” (UkrNDNC).
For example, DSTU 3768:2019 “Wheat. Technical Conditions” is the standard that governs wheat quality and classification. According to this standard:
- Soft wheat is divided into four classes.
- Hard wheat is divided into five classes.
The classification is based on the following quality indicators:
- Test weight
- Protein content
- Moisture content
- Damaged kernels
- Admixture content
- Hagberg Falling Number
Wheat is further categorised into two groups:
Group B – wheat of classes 3 to 5
Group A – wheat of classes 1 to 3
| Indicator | 1st Class | 2nd Class | 3rd Class | 4th Class |
| Test Weight (g/L), not less than | 775 | 750 | 730 | Not limited |
| Glassiness (%), not less than | 50 | 40 | Not limited | Not limited |
| Moisture Content (%), not more than | 14,0 | 14,0 | 14,0 | 14,0 |
| Grain Admixture (%), not more than | 5,0 | 8,0 | 8,0 | 15,0 |
| – Broken Grains | 5,0 | 5,0 | 5,0 | Within grain admixture |
| – Cereal Grains | 3,0 | 4,0 | 4,0 | Within grain admixture |
| – Germinated Grains | 2,0 | 3,0 | 3,0 | Within grain admixture |
| Foreign Matter (%), not more than | 1,0 | 2,0 | 2,0 | 3,0 |
| – Mineral Admixture | 0,3 | 0,5 | 0,5 | 1,0 |
| – Gravel, Slag, Ore | 0,15 | 0,15 | 0,15 | 0,15 |
| – Damaged Grains | 0,3 | 0,5 | 0,5 | 1,0 |
| – Fusarium-Affected Grains | 0,3 | 0,3 | 0,5 | 1,0 |
| – Harmful Admixture | 0,1 | 0,1 | 0,2 | 0,2 |
| Smut & Ergot (total) | 0,05 | 0,05 | 0,05 | 0.1 (0.05 smut, 0.05 ergot) |
| Grey Triticum | Not allowed | Not allowed | Not allowed | Not allowed |
| Corn Cockle | Within harmful admixture | Within harmful admixture | Within harmful admixture | Within harmful admixture |
| Each of Other Toxic Seeds | 0,05 | 0,05 | 0,05 | 0,05 |
| Shrunken Grain (%), not more than | 8,0 | 8,0 | 8,0 | 10,0 |
| Protein Content (% dry matter), not less than | 14,0 | 12,5 | 11,0 | Not limited |
| Wet Gluten Content (%), not less than | 28,0 | 23,0 | 18,0 | Not limited |
| Gluten Quality (VDK device units) | 45–100 | 45–100 | 45–100 | Not limited |
| Falling Number (s), not less than | 220 | 220 | 180 | Not limited |
The full text of the standard can be obtained from the National Standardisation Body of Ukraine.
Canada
In Canada, grain quality standards are regulated by the Canadian Grain Commission (CGC) – a government agency that oversees the grain industry, ensures quality control, and develops standards. The primary document that defines grain assessment rules is the Official Grain Grading Guide.
CGC classifies wheat based on its functional characteristics (e.g., suitability for bread-making, pasta production, etc.) and growing region. In general, two primary regions are distinguished:
- Western Canada
- Eastern Canada
Each region has multiple wheat classes, with the Official Grain Grading Guide establishing strict quality standards for each. For example, for Canada Western Red Spring Wheat (CWRS):
| Grading factor | No. 1 CWRS | No. 2 CWRS | No. 3 CWRS | CW Feed | Grade, if specs for CW Feed not met |
| Degree of soundness | Reasonably well matured, reasonably free from damaged kernels | Fairly well matured, may be moderately bleached or frost-damaged, reasonably free from severely damaged kernels | May be frost-damaged, immature or weather-damaged, moderately free from severely damaged kernels | Reasonably sweet, excluded from other grades of wheat on account of damaged kernels | — |
| Minimum test weight kg/hL (g/0.5 L) | 75 (365) | 72 (350) | 69 (335) | 65 (315) | Wheat, Sample CW Account Light Weight |
| Minimum hard vitreous kernels % | 65 | No minimum | No minimum | No minimum | — |
| Minimum protein % | 10.0 | No minimum | No minimum | No minimum | — |
| Variety | Any variety of the class CWRS designated as such by order of the Commission | Any variety of the class CWRS designated as such by order of the Commission | Any variety of the class CWRS designated as such by order of the Commission | Any class or variety of wheat excluding amber durum and CWSP | — |
Full information can be found in the Official Grain Grading Guide on the Canadian Grain Commission website.
The Role of Gafta in Grain Quality Assessment
More than 90% of global grain trade is conducted under Gafta (Grain and Feed Trade Association) standards and contract templates. Gafta not only establishes uniform contract rules but also plays a key role in grain quality control.
Specifically, Gafta:
- Accredits superintendents who ensure that grain quality complies with contract conditions.
- Defines sampling rules (Gafta 124) to guarantee the representativeness of quality analysis.
- Accredits laboratories in accordance with ISO 17025, the international laboratory quality standard.
- Establishes standardised grain quality analysis methods (Gafta 130).
Although Gafta does not define its own wheat classification, these mechanisms ensure a unified approach to grain quality assessment in international trade.
Grain Quality Assessment Methods
The primary document governing grain analysis in international trade is Gafta No. 130 (Analytical Methods). It contains standardised rules and methodologies for assessing key quality indicators such as moisture content, protein content, gluten, test weight, and admixture levels.
Gafta No. 130 incorporates both ISO international standards and Gafta-specific methodologies, which are used if no other standard is specified in the contract. Specifically, Gafta defines the following principles for grain quality analysis.
Sampling
Sampling must be conducted in accordance with Gafta No. 124 (Sampling Rules) to ensure that the sample is representative. This is critical for obtaining accurate results and avoiding disputes.
Sample Preparation
Sample preparation for analysis is carried out in accordance with Method 1.0 (Sample Preparation) of Gafta No. 130. The key principles include:
- Thorough grinding of samples to ensure homogeneity and representativeness.
- Minimisation of moisture loss and prevention of sample contamination during preparation.
- Use of appropriate equipment that does not generate excessive heat, to prevent alterations in the sample composition.
Selection of the Analytical Method
In the absence of a specific analytical method stipulated in the contract, internationally recognised ISO standards apply. Where no standard is specified, the laboratory is entitled to select another internationally recognised method. The chosen method must be stated in the Certificate of Analysis.
The most commonly used analytical methods, as per Gafta No. 130, include:
| Quality Indicator | Gafta (ISO) Analytical Method |
| Moisture | ISO 712:2009 |
| Crude Protein | ISO 20483:2013 (Kjeldahl method) |
| Wet Gluten | ISO 21415-2:2015 (mechanical method) |
| Bulk Density | ISO 7971-3:2019 |
| Admixture | ISO 7970:2011 |
| Physical Characteristics | ISO 7970:2011 or other standards by agreement (EN, USDA, GOST, CGC) |
The complete list of standardised analytical methods is available on the Gafta website.
Laboratory Requirements
All laboratories conducting analysis under Gafta No. 130 must be accredited to ISO 17025. These accredited laboratories issue official grain quality certificates, which carry legal weight in case of disputes.
Contracting Out (Sub-Contracting) Analysis
If a laboratory is unable to perform a specific analysis, it may subcontract the test only to another Gafta-accredited laboratory that also holds ISO 17025 accreditation.
By ensuring the use of clear, standardised analytical methods in accordance with Gafta No. 130, the system guarantees objectivity, transparency, and reliability in grain quality assessment.
Conclusion
Grain quality determines contract compliance, pricing, and supplier reputation. The majority of international grain supply contracts are governed by Gafta standards, which establish grain analysis procedures, laboratory accreditation, and superintendent control.
If you require legal assistance regarding Gafta contracts, grain quality disputes, or analytical issues, feel free to contact me via email, Telegram, or WhatsApp — I will help protect your interests.
