How to test natural colours stability?

Heat Stability

It's essential to know the heat stability of the natural colours before we use them in food like bakeries, beverages, confections, extruded products where the colour will be put through high temperature or periods of extended heat.

There are various ways we can test the stability of heat for different applications. Usually, we can determine the stability of colours by incubating the colour at the same time and when temperature is close to the customer's application.

Colour is measure with a colourimeter before the test and after being put through the heat process.

Colour must remain vibrant throughout the manufacturing process as well as the product shelf life.

That's why we test our colours to ensure they stay stable at different temperatures or not.

We start by preparing multiple samples in the application; in this example, we'll use beta carotene in beverages then we will measure the hue using a colourimeter. This measurement will serve as our baseline.

We want the colour to remain as close to this measurement as possible throughout the heat test. Once we have our baseline, we start the test.

Test

Multiple samples of the same beverage are store at different temperatures. One is refrigerating at four degrees Celsius, one is at room temperature at 20 degrees Celsius, & one is put in a hot box at 32 degrees celsius each week during the test.

We measure the colour of each sample to see if there have been any changes at the end of the test.

We take a final reading and compare it to the baseline from the start of the test as you will see the before and after readings are highly close, meaning the colour remains consistent throughout the test at all three temperatures.

Light Stability

It is the most commonly request test from the customers because customers want to know whether their product will retain the initial vibrancy.

The light stability test is a real-time test when the final packaging happening under the same lightning. For instance, Cool white UV, DE65 artificial sunlight under which the product will be store.

Under such conditions, when we have accurate and precise measurements using either a spectrophotometer can track the colour change.

And if due to some reason, real-time testing is not possible, maybe because of short development, accelerated light testing is done using high-intensity light.

Acid Stability

So It's another commonly request test from customers. It is generally specific to customers and applications where pH, temperature, & even time profile are particular to the application.

In this test, we add natural colours to the solutions at a range of pH levels where colour is measure for a specific time; if the colour is not faded, we consider it has good acid stability.

However, another stability test like alcohol, salt, flavour depends on specific customers’ requirements.

To even learn more about natural colour, click here SANTACOLOR.