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Nitrate Surveillance Monitoring Program (Annual Report May 2021 - March 2022)

Nitrate Surveillance: Appendix 4

Standard Operating Procedure for collecting samples

Last updated: 6 December 2022
Last updated: 6 December 2022

Field sampling and transportation of lettuce and spinach samples for the UK Nitrate Monitoring Programme.

Introduction

EC Regulation No. 1881/2006 requires Member States to monitor nitrate levels in lettuce and spinach. This document specifies the procedure to be followed for taking and transporting samples of lettuce and spinach to the laboratory in connection with the UK Monitoring Programme for nitrate. 
Principle:  Representative sampling of lettuce, or spinach, from the field in accordance with Commission Directive 1882/2006/EC. Transfer to suitable containers and transport to the laboratory under appropriate conditions.  Complete and despatch the sample pro-forma to the laboratory. 

Reference document

Commission Directive 1882/2006/EC of 20 Dec 2006 establishing Community methods of sampling for the official control of nitrate in lettuce. Official Journal of the European Communities. No. L364/25.

Materials and Equipment

Vegetable knife. 
Suitable insulated box for sample transportation. 
Ice packs. Sampling record pro-forma. 

Procedures

1.   Sampling and data logging

As far as possible samples should be taken at various places distributed throughout the lot. Avoid taking samples that are extensively spoiled. Also avoid taking samples from areas which appear to be unrepresentative of the field, and avoid taking samples from the extreme edges of the field

Take samples from a pattern similar to that on a "5-spot" die, or by walking a "W" pattern across the field, collecting a minimum of 10 heads of lettuce (or 10 spinach samples) to give a combined total minimum weight of 1 kg. Plants must be cut at ground level.  Trim off outer leaves to ensure the lettuce plant resembles a marketable product. Samples must not be cut or broken to produce the laboratory samples. 

Complete the "Sampling Record - UK Produce" pro-forma (Annex 1) and transfer this to a plastic bag to prevent damage in transit.

2.   Transportation to the laboratory.

Place each set of (minimum) 10 vegetables in a clean, inert container offering adequate protection from contamination and damage in transit. Ensure that suitable ice packs are included with the sample to ensure that the sample temperature is maintained below 10 0C during transportation to the laboratory. Include the completed pro-forma. Arrange despatch to the laboratory without delay. 
Transportation should ensure that samples arrive at the laboratory before 10.30am on the day after harvest.