Monitoring Melting Profiles of Fresh Cream with Formulaction’s Rheolaser CRYSTAL

For those working in the dairy industry, Formulaction’s Rheolaser CRYSTAL can help optimise butter production by measuring the melting profiles of fresh cream samples.

Fresh cream is the fatty part of milk and is made up of different triglycerides with a wide range of melting points, due to a mixture long and short chains, which can be either saturated or unsaturated. Seasonal changes in feeding directly impact this composition.

When cattle are held on fresh pasture the triglycerides tend to be unsaturated, whereas when they are kept in during the winter this produces saturated triglycerides. This variability directly impacts the type of butter that can be made at certain times of the year.

A higher ratio of unsaturated triglycerides leads to a reduction in the melting point of the produced butter, and this may affect its suitability for certain applications.

How does the Rheolaser Crystal Work?

The Rheolaser CRYSTAL operates using Diffusing Wave Spectroscopy (DWS), a multiple light scattering technique. Briefly, the motion of the microstructure is measured as function of temperature.

During heating and cooling, characteristic peaks can be acquired for phase transitions, such as melting, crystallization, and polymorphic transitions.

How can the Rheolaser CRYSTAL aid butter production?

Let’s take, for example, a specific butter created for puff pastry. Puff pastry is made by folding the pastry several times and introducing a high melting point butter. This butter is called “Beurre AOP de tourage”, which is usually made from cream with a high ratio of saturated triglycerides during the winter months.

Three batches of March cream (early, middle, and late) were studied immediately after pasteurisation. An aliquot of cream was introduced into the closed cell (~2mL) of the Rheolaser CRYSTAL and a temperature ramp of 2 °C / min was applied from 8 °C to 50 °C.

A characteristic peak at 34°C can be observed for the early March cream, whereas the middle and later creams have lower transitions. This shift to lower temperatures is due to the presence of more unsaturated triglycerides, due to the cattle being put out to pasture at the beginning of the spring.

The weekly monitoring of fresh pasteurized cream suggests that after the middle of March, the cream is no longer suitable for puff pastry butter.

In autumn, the reappearance of the peak will indicate the possibility of making the Beurre AOP de tourage butter again.

Therefore, this study shows us that the Rheolaser CRYSTAL can aid with routine measurements and determine the seasonal changes in cream.

By observing the mean melting temperature of fresh cream with the Rheolaser’s highly sensitive method, an exact indication on whether to produce individual butters can be provided.