Pouring point

The (or melting point ) is the lowest temperature at which a liquid or paste ceases to flow under the effect of cooling. This measurement is essential for evaluating the low-temperature stability , viscosity , and handling of free-flowing products such as oils, greases, bitumen, solvents, or molten polymers.

Determining the pour point helps prevent problems related to crystallization , solidification , or increased viscosity during storage, transport, or use in cold conditions.

Principle and method of analysis

The pour point analysis is performed according to international standards ASTM D97 or ISO 3016 , which govern the controlled cooling procedure of a sample.

The principle involves gradually lowering the temperature of the liquid in a standardized tube, then observing the point at which the fluid stops flowing when the container is tilted. This temperature is recorded as the pour point .

Modern instrumental methods, such as differential scanning calorimetry (DSC) , allow for the precise determination of thermal transitions associated with the freezing or partial crystallization of the product.

This analysis applies to many matrices:

• vegetable oils, fats and oils,
• lubricants, bitumen, solvents,
• cosmetic and nutraceutical formulations,
• polymers and thermoplastic resins.

For further thermal studies, also see:

• Differential scanning calorimetry (DSC) to characterize thermal transitions,
• analysis (TGA) to measure thermal degradation,
• and the measurement of the melting point to determine the reverse transition when hot.

Industrial applications

Pour point measurement is used in many sectors to ensure product performance, safety, and quality

• Agri-food and nutrition : determining the cold behavior of edible oils, margarines and animal fats to ensure homogeneity and stability.
• Cosmetics : characterization of the consistency and stability of natural balms, creams or waxes at low temperatures.
• Nutraceuticals and plants : control of oily extracts and plant macerates sensitive to cold.
• Materials and polymers : analysis of the behavior of molten resins and thermoplastic polymers during their cooling.
• Industrial chemistry : control of the fluidity of lubricants, solvents and bitumens in production and transport processes.

This data is crucial for optimizing formulation , predicting storage conditions, and ensuring the conformity of finished products .

Analytical interest and complementarity

The pour point is integrated into a set of thermal and rheological analyses allowing for a complete understanding of product behavior at temperature:

• A point of confusion for determining the onset of component precipitation,
• Melt flow index (MFI) for measuring viscosity in the molten state,
• Enthalpy of fusion to quantify the energy required for the thermal transition,
• Accelerated aging tests to anticipate variations in fluidity over time.

These complementary analyses offer a complete characterization of the thermal, rheological and mechanical behavior of liquid or semi-solid products.

YesWeLab Services

YesWeLab collaborates with a network of partner laboratories accredited to ISO 17025 and/or COFRAC , experts in thermal and physicochemical analyses .
Our scientific teams support you in defining the protocol best suited to your needs: formulation study, stability testing, or conformity validation according to ASTM and ISO standards.

Thanks to the YesWeLab digital platform , centralize your requests, track your samples, and retrieve your analysis reports directly online.
Since 2020, YesWeLab has been supporting the cosmetics, food processing, and materials industries in their thermal characterization and product stability .

For any specific request or quote, contact our scientific team today.