Protein in Ready-to-Drink (RTD) Beverages: Protein and Gelling

Welcome to Protein in Ready-to-Drink (RTD) Beverages: Protein and Gelling, the second of a four-part series focused on formulation insights surrounding protein fortification in RTDs.

Be sure to check out part one to get the most out of this series, Protein in Ready-to-Drink (RTD) Beverages: Protein and Heat.

Proteins don’t just degrade; gelling is another challenge that can arise when applying heat to proteins. Gelling occurs when the proteins begin to aggregate (bind together) to form a structure much more similar to pudding than a drink. This undesirable consistency it disliked by formulators and customers alike. To overcome this challenge, one can use a category of ingredients called sequestrants.

Sequestrants, Protein & Gelling

Sequestrants gather up molecules that would otherwise bind to protein molecules and cause gelling. Phosphates are common ingredients found in high-protein RTDs and often fill the role of a sequestrant. One ingredient that fits in the sequestrant category is sodium hexametaphosphate (SHMP). Still, there are a variety of other forms of polyphosphates (phosphates with at least four phosphorus atoms work the best) that also play this role is RTD formulation.

Sometimes the gel can be very loose, and merely swirling or shaking the bottle is enough to turn it back into a liquid. Other times, gelling can be very Jello-like and even take on the shape of the container. This consistency is mainly an issue with milk protein concentrate, which is common in vanilla or chocolate flavored neutral-pH beverages. The sequestrants help to protect the Casein proteins from binding to each other.

Remember the sweater analogy introduced in Part 1? To further expound up that example, the sweater’s yarn rubs together, and the strands start to connect into a large pill unless you do something to protect the individual strands of yarn (like adding fabric softener). Sequestrants are that fabric softener.

When choosing the correct sequestrant to combat gelling, you should consider:

Claims 

Consider the clean label trend; some sequestrants are perceived as more “clean label” by consumers (i.e., Sodium Phosphate vs. Sodium Hexametaphosphate).

Regulations

For example, organic dairy products can use disodium phosphate (DSP), while plant-based organic RTDs cannot.

Ion concentration 

Ions can impact the degree of gelation. A higher concentration of ions requires higher sequestering capacity.

Cost comparison

As with all ingredients, the cost will be a deciding factor, and your formulator should be able to navigate functional phosphates at a range of prices.

How can you tackle these challenges?

You will need a variety of specialized knowledge and equipment to accurately bench, test, and trial protein fortification in RTDs. The best course of action is partnering with a consultant with access to the required equipment and knowledge of how closely it will mimic a scale-up.

Agropur is both a formulator and a contract packer. Our team has a variety of industry contacts if you are looking for something specific that we don’t service. Do not hesitate to reach out to our Technical Sales Account Manager, Emily Ross. She is a wealth of information and would be happy to assist you as you start your journey.