Using natural thickeners to achieve clean label products

14 August 2020 | Jo Baker-Perrett, Technical Manager

If you’re like most people, then picking up a product to find unfamiliar, chemically synthesised ingredients on the back is a big turn-off – it may even dissuade you from purchasing it. You’d probably prefer to see ingredients that are easily recognised, understood and pronounced. We call this ‘clean label’: a popular consumer-driven movement that sees the return of ‘real food’ and transparency through authenticity. For this reason, manufacturers are seeking to replace artificial ingredients with those from more natural sources that will appeal to consumers. But that’s no easy task. Many key functions in the foods we eat are performed by chemically synthesised ingredients, and for a good reason - so finding natural alternatives that work as well is a real challenge.

On the hunt for natural thickeners

As part of our research, we’ve been evaluating the performance of plant-based food ingredients against existing additives. Our recent study investigated the potential of using sorghum, millet and chickpea flour as thickeners in the filling of apple pies when compared to refined starch (the pies’ usual thickening agent).

Why is starch an effective thickener? Because, when heated, this carbohydrate gelatinises, causing the starch granules to absorb water and expand – significantly increasing viscosity. Sorghum, millet and chickpea all contain a significant amount of starch, so we attempted to thicken the filling of an apple pie by incorporating these ingredients as flours. The added benefit is that these flours also contain micronutrients which may further promote good health.

What we found

Of the three flours tested, sorghum showed the greatest potential as an alternative thickener in processed foods. It absorbed the most water and formed the most viscous gel when tested on a rapid visco analyser. Millet followed closely, and other rheometry analysis showed that they both demonstrated rheological properties similar to refined starch when added in at elevated levels.

In layman’s terms, this means manufacturers could reformulate their apple pie’s filling with one of these alternative flours to achieve a similar gelling effect as seen with refined starch - assuming about three times more of one of these flours is added. Better yet, they could substitute ‘modified starch’ with ‘millet flour’ on this product’s ingredients list, increasing its appeal to consumers looking for ‘cleaner’ label products.

But what about the chickpea flour?

As a thickener, the chickpea flour didn’t perform as well as the others that were tested. However, what we did observe was its ability to form a strong gel structure that didn’t easily breakdown. Why? Well, unlike the other two materials tested, chickpea contains a high amount of protein (about 20%), so we believe this protein interacted with the starch granules creating a starch-protein gel network. More testing would be required to confirm this hypothesis.

Manufacturers could potentially find a use for this strong gelling behaviour in other specific applications. However, it’s worth noting that after testing, the apple filling containing chickpea flour underwent ‘syneresis’: a process in which the gel network contracts, ultimately squeezing out some of the water.

Beyond sorghum, millet and chickpea

The results we found for these flours may apply to a number of other pseudo-cereals and ancient grains, widening the industry’s choice of potential alternative ingredients to use. Next, our research will focus on the functionality of novel ingredients in doughs and batters.

How can we help you?

Whether you’re looking to replace artificial ingredients with those from more natural sources or you’re seeking support with product innovation or reformulation to meet nutrition and health targets, contact us to find out how we can help.

About Jo Baker-Perrett

After graduating from his master’s degree in chemistry from the University of Sheffield in 2014, Jo worked in education before joining us in 2016. Since then, Jo has worked in the bakery department, and then in Food and Drink Microstructure, after which he started managing this section, which is mainly focused on physical characterisation and ingredient functionality.

Jo has published various Campden BRI research reports and trade press articles, as well as producing regular food industry blogs for our website.