Clause 7.4.1 – Handling of Test Items

Clause 7.4.1 – Handling of Test

Purpose of this Clause

In food testing laboratories, test items (samples) can easily deteriorate or get contaminated if not handled properly. This clause ensures that every sample received by the lab remains in the same condition as when it was collected, so the test results are valid, reliable, and defensible.

It also helps in:

• Maintaining traceability of samples

• Preventing mix-ups or misidentification

• Protecting the rights of customers, ensuring their samples are handled carefully

• Demonstrating that the lab maintains control over test materials at every stage

The clause mentions several key stages:-

1. Transportation of Samples

If the laboratory itself collects the sample or receives it from clients, it must ensure that the sample’s integrity is not affected during transport.

Example:
A sample of pasteurized milk must be kept between 2°C–8°C during transportation to the lab.
If transported at room temperature, microbial growth can occur, giving false high counts during analysis. Hence, the laboratory’s transport procedure should specify the use of ice boxes with temperature monitoring equipment .

Best Practice:

• Use cool boxes, insulated containers, or dry ice for frozen samples.

• Maintain a sample transport log with temperature records and time of collection and receipt (if sample collected or sampled by the lab).

• Train collection personnel on proper sample packaging and labeling.

2. Receipt of Samples

When samples reach the laboratory, they must be checked before acceptance.

Example:
On receiving a pack of biscuits for moisture and fat testing, the lab must verify:

• The sample label matches the sample request form

• The quantity is sufficient for analysis and retesting

• There is no damage or leakage

• The temperature condition (if applicable) is within limits

Best Practice:

• Record details in a Sample Receipt Register or LIMS

• Assign a unique sample ID immediately

• Document any deviation or non-conformance (e.g., broken seal, inadequate quantity) and inform the customer for further instructions

3. Handling of Samples

Proper handling ensures that no contamination or alteration occurs before or during analysis.

Example:
When sub-sampling spices for aflatoxin testing, the analyst must use clean, dry stainless steel spoons and sample dividers, ensuring no cross-contamination from other samples.

Best Practice:

• Use dedicated tools and clean benches

• Follow personal hygiene and cross-contamination control measures

• Handle perishable items (like meat or curd) under controlled temperature

4. Protection of Samples

Samples must be protected from contamination, damage, or tampering.

Example:
If a fruit juice sample is received in a plastic bottle, it should be kept closed tightly and stored in a refrigerator at the recommended temperature until testing.

Best Practice:

• Use tamper-evident seals

• Restrict access to authorized personnel only

• Maintain records of storage conditions

5. Storage and Retention

Samples may need to be stored for a certain period before testing, or retained after testing for verification or customer queries.

Example:
After testing a rice sample for pesticide residues, the lab may retain a portion for 30 days or as per lab policy for possible re-testing if the customer disputes the result.

Best Practice:

• Define retention periods for different sample types (e.g., perishable vs. non-perishable)

• Store in appropriate conditions — refrigerators, freezers, or dry shelves

• Ensure segregation between tested and untested samples

6. Disposal or Return of Samples

Once testing is completed, the lab must dispose of or return the remaining samples safely and in accordance with procedures.

Example:

• For microbiological samples, like curd or meat, the remnants should be autoclaved before disposal to prevent contamination.

• For customer-provided proprietary products, the client may request the return of leftover material.

Best Practice:

• Maintain disposal records with date and method

• Follow biohazard and chemical waste disposal rules

• Obtain acknowledgment from the customer when returning samples

7. Following Customer Instructions

If the customer provides specific handling or storage instructions, these must be strictly followed.

Example:
If a beverage manufacturer specifies that the sample must not be frozen before analysis, the lab must ensure that it is stored only at 4°C, not in a freezer.

Best Practice:

• Record special instructions in the sample receipt form

• Label samples with “Special Storage” tags

Documentation and Records

To comply with Clause 7.4.1, the laboratory must maintain the following:

• Sample Handling Procedure (SOP) — covering all steps from transportation to disposal

• Sample Receipt Register / LIMS Records

• Sample Identification Labels

• Environmental condition logs (temperature, humidity)

• Retention and Disposal Records

• Customer communication records (in case of damaged or unsuitable samples)