Overview
EN ISO 3593:1994 specifies a standardized method for the determination of ash content in starch. Developed by the International Organization for Standardization (ISO) and adopted by CEN, this standard ensures reliable measurement of total mineral residue (ash) by incinerating a starch sample at 900°C until all carbon is removed. The procedure provides an accurate assessment of both natural and added mineral substances within starch, supporting quality control and regulatory compliance in food and industrial applications.
This method is applicable to native starches and modified starches containing up to 2% ash. It is not suitable for hydrolysis products, oxidized starches, or products containing more than 0.2% chloride. For such cases, users are referred to ISO 5809.
Key Topics
- Sample Incineration: The core of EN ISO 3593:1994 lies in incinerating a weighed test portion of starch in a furnace at 900°C until all carbon is removed, leaving only inorganic ash.
- Scope Limitations: Not applicable to products with high chloride content (>0.2%), hydrolysis products, or oxidized starches. For higher chloride content or other starch derivatives, refer to ISO 5809.
- Combined Mineral Evaluation: The method simultaneously measures natural mineral content and any added (non-organic) substances in starch samples.
- Repeatability and Reporting: The standard defines acceptable limits for repeatability and provides guidelines on reporting results, including sample identification and testing conditions.
Applications
The ash determination method outlined in EN ISO 3593:1994 serves several practical roles in the starch and food industries:
- Quality Assurance: Assists manufacturers and quality control laboratories in verifying that starch products conform to regulatory and internal specifications for mineral content.
- Product Classification: Enables precise distinction between native and modified starches based on their inorganic residue, supporting product labeling and classification.
- Process Monitoring: Useful in monitoring the production processes of starch to ensure consistent purity and detect contamination with foreign minerals.
- Regulatory Compliance: Supports compliance with national and international food safety regulations, which often stipulate maximum allowed ash levels in food-grade starch.
Industries benefiting from this standard include:
- Food and beverage production
- Pharmaceutical manufacturing
- Paper and textile processing
- Bioplastics and biodegradable product development
Related Standards
Several international standards are closely related to EN ISO 3593:1994 for starch analysis:
- ISO 5809: Starch and derivatives - Recommended for products not suitable under EN ISO 3593:1994, such as those with high chloride content or oxidized starches.
- ISO 1666: Starch - Determination of moisture content by oven-drying methods, frequently referenced for sample preparation and calculation in ash determination.
- EN ISO 3726: Starch - Determination of sulphated ash (in advanced draft stages).
- ISO 17305: General analytical quality guidelines for starch and derived products.
By adhering to EN ISO 3593:1994, laboratories and manufacturers ensure methodological consistency and robust, internationally comparable results in the determination of ash content for starch and starch-derived products.