TNV Inspection Division

The object of quality classification is very important in the world trade of cereals and cereal products. From every commercial transaction to all safety checks, and each quality analysis on any product – one action precedes these: sampling. ISO 24333:2009 States the protocol for this has been established internationally on ISO 24333:2009 – Cereals and cereal products — Sampling.

This specification provides a tested, world-accepted sampling plan and method for procuring a representative sample of the grain lot. Since the only material ever subjected to laboratory control is this sample object, the credibility of the entire quality assessment activity stands and falls with the correctness of sampling.

For organizations involved in the grain supply chain, adherence to ISO 24333 is critical for reducing transactional risks, validating contractual obligations and expressing a dedication to quality. TNV Inspection Body performs sampling inspection in accordance with ISO 24333:2009 as a neutral, third-party organization.

Key Objectives of the Standard

ISO 24333:2009 This document specifies the requirements for drawing and preparation of a test sample. The standard is designed to:

  • Establish a consistent, reproducible method for sampling of cereals and their products.
  • Verify the sample collected is representative of the total from which it came.
  • Do not adulterate the sample; keep its features as-is while collecting and conveying it.
  • Promote fair and transparent commerce by setting a common basis for all parties.

The Role of a Standardized Sampling Procedure

Complying with a protocol such as ISO 24333 is necessary in order to ensure the proper and fair trading of cereals. It is a worldwide accepted common language for verifying quality by buyser, seller and regulator.

  • Ensures Contractual Quality: It offers an impartial way to establish for the seller and buyer that a shipment is in line with the quality contract.
  • Facilitates Fair Trade: A fair, and exemplary sample ensures a good value of the consignment; to the advantage of all involved.
  • Protects Your Supply Chain: Proper sampling is the first line of defense against potential issues, such as contamination or moisture levels, within your product prior to it continuing down the supply chain.
  • Ensures Market Access: Shipments along with inspection certificate from accredited laboratory confirming to sampling as per ISO Standards meets the lesser obstruction in export market.
The role of standardized sampling procedure as per ISO 24333:2009 for fair and accurate quality inspection of cereals and grains by TNV.

Fundamentals of ISO 24333 Sampling

The guideline is based on key principles that are intended to deliver the fact of final sample which resembles to original lot.

Achieving a Representative Sample

The purpose of this practice is to ensure that every individual particle in the lot, whether it’s bulk material stored in a silo, transported by truck or contained within multiple bags, has an equal statistical probability of being part of the sample. This is done by extracting, a pre-determined number of sub-samples from different parts of the lot, and are referred to as ‘increments’. These increments are pooled to constitute a composite whole and the sample is proportionately reduced in order to generate the final laboratory aliquot.

Maintaining Sample Integrity

The sample’s state must be maintained between the time of drawdown and its reception at the laboratory. This involves:

  • With clean and dry sampling tools, utensils and containers.
  • Keeping the sample safe from the elements such as sun, rain and humidity that with changes its moisture content.
  • Guarantee of sample liberation from interferences with foreign matters, residues or other substances.
  • Treating the sample in such a manner as to avoid loss of either fine or coarse fragments.

Essential Criteria of ISO 24333

ISO 24333 states requirements to be fulfilled in the process of sampling.

· The Sampling Plan

Before he starts, the workmen will have to agree a plan. This includes recording the lot size, the commodity to be sampled and finding from a table in the standard file the number of incremental samples that are required. The code distinguishes between sampling from lots that are inactive (static) as opposed to moving ones (lots in motion such as a taken belt conveyor).

· Specified Equipment

Instruments used need to be correct for the particular cereal and lot type being analysed in order to prevent grain damage or bias. The standard includes items such as:

  • Hand driven sample-probes and sample-spears with correct length and orifice-diameter.
  • Mechanical devices for withdrawing portions from a flow of grain.
  • Disviding devices, for example riffle dividers to guarantee that a representative connection is maintained between the subsamples.

· Trained and Qualified Personnel

The norm emphasizes that sampling is to be performed by trained and experienced personnel. For valid results, it is crucial to properly operate the equipment and follow the sampling plan and to be able to deal with samples without degradation of quality. The TNV inspectors are deeply trained in all of these methods – to take the samples reliably and objectively.

· The Sampling Process

There is a clear process to follow:

  • Step 1 Taking a sample of Incremental Points: Selecting the desired number of points distributed within the lot.
  • Step 2 Consolidation of the Bulk Sample: All incremental samples were mixed together and well homogenized.
  • Step 3 Laboratory Sample Preparation: Generating the small laboratory sample by breaking down an aliquot of the sample to create one or more smaller, yet still representative samples.

Sealing, Labeling, and Reporting

When final laboratory samples are ready for shipment, they should be packed in clean, stable, moisture-resistant containers. Every sample needs to be bagged and well-labeled for complete traceability. A thorough sampling report has to be established with date, point of interest, product and quantity extracted, principle applied, the measures adopted and any comment of interest.

Who Should Use ISO 24333?

This standard is critical for multiple interested parties within the agricultural and food sectors:

  • Grain Producers and Farmers
  • Commodity Traders and Exporters
  • Silo and Warehouse Operators
  • Grain Millers and Food Processors
  • Quality Control Laboratories
  • Government Regulators and Inspection Agencies
  • Shipping and Logistics Companies

Step by step guide to ISO 24333 certification process

It’s important to note that an organization cannot get “certified” to ISO 24333. Rather, an inspection agency is accredited to conduct sampling as per this standard. Equipment is calibrated in alignment with the standard’s requirements.

Applicable to Grain Handlers & Processors (How to Comply)

If you deal with or process grain, compliance with ISO 24333 demonstrates a commitment to best quality practices and helps reduce trade friction.

  1. In-house Gap Analysis: Evaluate your current sampling practices and compare them to the requirements described in ISO 24333. Identify any differences in your equipment, protocols, and documentation.
  2. Create a Quality Management System (QMS): Formally document all your procedures. This QMS should cover topics such as how to implement a sampling plan, the calibration and cleaning of equipment, methods for training personnel, and record-keeping.
  3. Purchase the Right Equipment: Acquire the appropriate sampling probes, spears, and mechanical dividers as specified in the standard. This is essential to obtain a representative sample that is free from bias.
  4. Staff Training: Train all personnel involved in sampling on the specified procedures and the basic principles of maintaining sample integrity.
  5. Follow and Document: Consistently follow your new protocols. Maintain a written record of every sampling event, including a description of the sample, the date, the name of the individual who took the sample, and the relevant lot data.
  6. Internal Audits: Periodically audit your process to ensure it is being followed correctly and remains effective. This ensures that standards are maintained and prepares you for any external audits.

Industry how required ISO 24333

  1. Milling & Processing Industry: Proper sampling is essential to assure that the incoming cereals meet the moisture, purity and other quality standards necessary to pro-duce a uniform final product.
  2. Grain Storage & Warehousing: Systematic sampling provides operators the ability to keep an eye on the condition of stored grain to detect such concerns as insect infestation, moisture pockets and spoilage before they impact an entire lot.
  3. Import & Export Trade: For international traders, sampling to an internationally-accepted standard such as ISO 24333 is essential in verifying quality at loading and discharge, avoiding costly rejections and disputes.
  4. Agency And Inspection (Author): Routine sampling is to facilitate enforcement of laws, and surveillance for contaminants, particularly ensuring safety of cereals entering the national food supply.
  5. Testing Laboratories: The standard offers laboratories comparable and representative samples, the basis for accurate mycotoxins testing, pesticide residues, GMOs and othe r key parameters.

Typical Grain Sampling Problems and the ISO 24333 Solutions

  1. Issue: Inconstant sampling methods Diverse non-standardised techniques may result in discrepancies between operators and can cause unreliable results. ISO 24333 2009
    • Solution: It specifies a single globally recognized set of specialized procedures guaranteeing continuity, regardless of who the operator is or where it takes place.
  2. Challenge: Sampling bias Collecting samples from accessible spots, such as the top of a truck, can skew the sample so that it does not truly reflect the condition of an entire lot. ISO 24333
  • Solution: The standard requires that increments are randomly or systematically taken from throughout the entire consignment so as to eliminate any bias, and to obtain a representative sample.
  1. Challenge: Single contamination The sample may be contaminated due to dirty devices or incorrect operation, which causes inaccurate testing results. ISO 24333
    • Resolution: Procedure is defined by standard that maintains the sample’s integrity from field collection through to transport to the laboratory and carries clean equipment, proper handling of sample and sealed container.

The Function of an Accredited Independent Inspection Body

For cereals and cereal products transactions, an independent third party inspection company offer confidence and credibility. Independent of any interest group, a recognised body would provide an impartial and objective assessment that could be used to enhance the level of trust between trading partners.

TNV, an accredited Inspection Body to UAF system in accordance with ISO/IEC 17020 can perform this critical verification activity. In conjunction with ISO 24333:2009 and other food product standards listed in our scope of accreditation, we provide the following services;

  • Third-Party Random Sampling: Samples taken from grain lots at farmland, storage and port facilities following the ISO 24333.
  • Loading & Unloading Watch: Counting during loading/unlaoding.
  • Quality & Condition Inspection: Inspecting visually and on site as part of a pre-shipment or post-landing control.
  • Detailed Inspection Reports: Formal reports explaining each step and all findings – crucial evidence for all interested parties.

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For professional, accredited, and globally recognized inspection services, Contact TNV Inspection Division today.

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Frequently Asked Questions(FAQ)

What is ISO 24333:2009?
ISO 24333:2009 is an international standard for sampling cereals and cereal products. It explains how to collect representative samples from grain lots for reliable testing and quality evaluation.
Why is ISO 24333 important for cereal sampling?
It helps ensure that the sample taken from a grain lot truly represents the full lot. This reduces testing errors, trade disputes, and quality-related risks.
Who should use ISO 24333:2009?
Grain producers, exporters, importers, silo operators, warehouses, food processors, testing laboratories, and inspection agencies can use this standard.
Is ISO 24333 a certification standard?
No. ISO 24333 is not a certification standard. It is a sampling standard used to guide proper sampling methods for cereals and cereal products.
How can TNV Inspection Division help with ISO 24333?
TNV Inspection Division can support third-party sampling, loading and unloading supervision, quality inspection, condition checks, and detailed inspection reports for cereal and grain lots.
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