EN 645:1993

Overview

EN 645:1993 - adopted in Slovenia as SIST EN 645:1997 - is a CEN standard that defines the method for the preparation of a cold water extract from paper and board intended to come into contact with foodstuffs. The standard gives a reproducible procedure to obtain an aqueous extract suitable for subsequent chemical or analytical investigations of extractives that may migrate from packaging into food.

Key topics and requirements

The standard focuses on methodical, contamination‑controlled preparation of an extract rather than on specific analytical limits. Key technical topics covered include:

• Scope and purpose: applicability to paper, board and related materials used as food contact materials.
• Sample handling: instructions for representative sampling, conditioning and storage to avoid cross‑contamination before extraction.
• Extraction procedure essentials: preparation steps for producing a cold water extract intended for further analysis (the standard specifies the method sequence rather than analytical determinations).
• Separation and recovery: guidance on separating liquid extract from solid residues and on preserving the extract for testing.
• Quality and traceability: requirements for labelling, documentation and keeping records of batch/sample identification to support traceability.
• Hygiene and contamination control: precautions to prevent artefacts from equipment, reagents or handling that could affect results.

Note: EN 645 describes the preparation technique for investigation of certain extractives; it does not itself set migration limits or identify which chemical compounds must be tested. Users apply analytical methods to the prepared extract to quantify specific substances.

Applications

EN 645 is practical for organizations involved in ensuring safety and compliance of paper-based food packaging:

• Testing laboratories preparing extracts prior to chemical analysis (e.g., chromatography or spectrometry).
• Paper and board manufacturers validating raw materials and finished products for food-contact suitability.
• Food packaging converters and designers assessing materials used for direct or indirect food contact.
• Regulatory and conformity assessment bodies using standardized extraction procedures to compare test results across laboratories.
• Research groups studying migration behavior and extractives in food contact papers.

Using a standardized extraction method increases comparability of test results and supports compliance with food safety regulations.

Related information

• Standard reference: EN 645:1993 (CEN), national adoption SIST EN 645:1997.
• ICS codes: 67.250 (Materials and articles in contact with foodstuffs), 85.060 (Paper, board and pulps).
• Related topics: food contact materials testing, migration testing methods, analytical chemistry of packaging extractives.

Keywords: EN 645:1993, cold water extract, paper and board, food contact materials, extractives, CEN standard, food packaging testing, SIST EN 645.