ISO 1741:1980

Overview

ISO 1741:1980 specifies a vacuum oven method for determining the loss in mass on drying of dextrose products. This standard applies to both anhydrous dextrose and dextrose monohydrate. The method involves drying a precise test portion of the sample at 100 °C under a reduced pressure not exceeding 135 mbar, allowing for accurate measurement of moisture and volatile content.

This standardized procedure ensures reliable and reproducible results for quality control, product specification, and compliance testing in industries handling carbohydrate products like glucose and dextrose.

Key Topics

• Scope and Applicability

  • Suitable for both anhydrous and monohydrate forms of dextrose
  • Focus on accurate determination of moisture content through mass loss

• Principle of the Method

  • Drying the sample in a vacuum oven at 100 °C
  • Reduced pressure (<135 mbar) facilitates removal of moisture without thermal degradation

• Required Apparatus

  • Analytical balance with precision up to 0.0002 g
  • Metal or glass dish with tight-fitting lid
  • Electrically heated vacuum oven with temperature and pressure control
  • Vacuum pump and drying train to maintain pressure and remove moisture
  • Desiccator with efficient desiccant for cooling and weighing

• Test Procedure

  • Homogenize and prepare the test sample (approx. 5-10 g)
  • Pre-dry and weigh the sample container and lid
  • Dry the sample uncovered in the vacuum oven for 4 hours at specified conditions
  • Cool in desiccator and determine loss in mass

• Calculations and Reporting

  • Results calculated as percentage loss by mass from initial weight
  • Average of two determinations reported for accuracy
  • Include detailed operating conditions, deviations, and sample identification in test report

Applications

• Quality Control in Food Industry
  Ensuring moisture levels in dextrose products meet regulatory and safety standards.
• Pharmaceutical Manufacturing
  Validating moisture content to maintain stability and shelf life of glucose-based formulations.
• Chemical and Carbohydrate Analysis
  Determining accurate water content in dextrose powders for research and production efficiency.
• Supply Chain and Raw Material Verification
  Confirming supplier consistency by standard moisture measurement of carbohydrate ingredients.

This vacuum oven method is critical in minimizing errors introduced by air-drying techniques, enhancing precision in moisture or volatile content evaluation.

Related Standards

• ISO 712:2019 – Methods for moisture determination in general foods, for comparison with alternative moisture testing procedures.
• ISO 787-13:1981 – General methods of chemical analysis for carbohydrates, complementary to specific drying methods.
• ISO 2171:2007 – Determination of moisture content by drying for starch, relevant for carbohydrate product testing.
• AOAC Official Methods – Additional test methods for moisture and volatile content in food substances, useful for cross-validation.

These related standards help laboratories choose appropriate moisture determination techniques based on sample type and required accuracy.

Keywords: dextrose, loss in mass on drying, vacuum oven method, moisture determination, ISO 1741, carbohydrate analysis, glucose testing, anhydrous dextrose, dextrose monohydrate, vacuum drying, moisture content measurement, quality control, pharmaceutical testing, food safety standards.