Beverages based on rice, nuts, grains and/or soybeans (RNGS) are increasingly popular and gaining market share around the globe. But there’s a challenge for product developers and quality managers and that is how to predict the shelf-life stability of these products already in the lab. Until today there has not been a way to make that assessment, but a newly developed test method has shown promising results.
RNGS beverages are marketed as simple and natural. But for the food processor the endless possibilities to combine different ingredients, as well as seasonal variations and differences depending on where raw materials are grown, mean that these products are anything but easy when it comes to tailoring and maintaining a consistent industrial process.
The only completely safe way to determine a product’s shelf-life stability is to simply put it on the shelf and wait. Repeated analysis will show whether the product can handle one, two, three months, or perhaps half a year on the shelf without deterioration. Of course this time-consuming process is not very practical, whether in product development or in continuous quality control.
One established way to predict shelf-life stability of dairy milk is to measure the homogenizing efficiency using the so-called NIZO method, which compares the fat content in different layers and provides a simple index. However, this method does not work for RNGS beverages, which are often milk-like.
Instead, a development of the NIZO-method, developed in collaboration with two world-leading RNGS producers and where lab results have been correlated with real shelf-life tests, has shown promising results for the assessment of two important parameters for shelf life stability in RNGS beverages, namely creaming and sedimentation.
The method, which we call the RNGS Stability Test, aims to objectively predict the shelf life stability without a need of real life storage tests. The problem to solve has been whether it is possible to achieve correlation between a fast and effective method – an “accelerated” test of various products and values – and the same products stored under various periods of time.
With the right homogenizing efficiency, both sedimentation and creaming can be maintained at controlled, foreseeable and acceptable levels. The product can be given the right quality with respect to the sensory characteristics – taste, mouthfeel, viscosity, etc. – and it might be possible to minimize the use of additives such as stabilizers and emulsifiers. Also, “over homogenization” can be avoided, meaning both reduced energy costs and enhanced quality of the end product.
All in all, this method has the potential to serve as an important aid in product development by giving crucial input to the assessment of a product’s life cycle.
Download our white paper, which provides an introduction to the development of an objective method for measuring shelf life stability of RNGS products.