SIST ISO 750:1998 PDF

Overview

SIST ISO 750:1998 - Fruit and vegetable products - Determination of titratable acidity is an international standard developed by ISO Technical Committee 34/SC 3. This standard outlines two recognized laboratory methods for the precise determination of titratable acidity in fruit and vegetable products: the potentiometric reference method and a routine method using a colored indicator. Effective assessment of titratable acidity is critical in quality control, research, and safety evaluation within the agricultural and food products industries.

Titratable acidity is a key parameter influencing the flavor, preservation, and processing behavior of fruits and vegetables. SIST ISO 750:1998 provides globally harmonized methods to ensure the reliability and repeatability of results, supporting consistent product quality across international supply chains.

Key Topics

• Determination Methods

  • Potentiometric method: Utilizes a pH meter and sodium hydroxide titration for accurate endpoint determination.
  • Routine (indicator) method: Employs phenolphthalein as a color indicator during titration with sodium hydroxide; not recommended for colored products or wines.

• Sample Preparation

  • Clear procedures for both liquid and solid fruit/vegetable matrices.
  • Guidance on removing CO₂ from carbonated products and handling frozen, dried, or homogenized samples.

• Calculation and Reporting

  • Results can be expressed in millimoles of hydrogen ions per 100 g or 100 ml of product.
  • Alternative expression in grams of specific acids per 100 g/ml is provided using acid-specific factors.
  • Emphasizes the importance of sample representativeness and clear documentation in the test report.

• Repeatability and Reliability

  • Specifies repeatability criteria to ensure laboratory consistency.
  • Full reporting requirements for transparency and traceability.

Applications

SIST ISO 750:1998 is highly relevant for laboratories, food producers, regulatory bodies, and researchers involved in:

• Quality Control: Routine monitoring of acidity in fruit juices, canned fruits, vegetables, brines, and fermented products.
• Product Development: Determining the impact of acidity on taste, texture, shelf life, and compliance with regulatory limits.
• Regulatory Compliance: Supporting labeling requirements and safety standards for domestic and export markets.
• Research and Analysis: Standardizing data collection in scientific studies, especially when comparing product batches or evaluating new processing techniques.

By adopting SIST ISO 750:1998, organizations can ensure their measurement practices align with international best practices, facilitating market access and consumer confidence.

Related Standards

For broader context and compatibility, SIST ISO 750:1998 can be used alongside other standards in the area of food testing and product evaluation, such as:

• ISO 2173 - Fruit and vegetable products - Determination of soluble solids - Refractometric method
• ISO 5528 - Fruit and vegetable products - Determination of water-insoluble solids
• ISO 1842 - Fruit and vegetable products - Preparation of samples and methods of analysis

These related standards help build a comprehensive approach to the analytical assessment of fruit and vegetable products, fostering safety, quality, and international harmonization in food testing.

Keywords: titratable acidity, fruit and vegetable products, SIST ISO 750:1998, food testing standards, potentiometric titration, food quality control, laboratory methods, agricultural products, acidity determination, food safety standards.