Scientists Find Way to Make Whey Protein Shakes Smoother and Less Bitter

Anyone who has pushed through a protein shake knows the complaints: a chalky film in the mouth, a thick texture, a bitter edge. A team of researchers has now traced part of that problem to the way whey protein is made, and says a change in filtration can fix it.

The work comes from scientists at the University of Reading, Aberystwyth University, and Arla Foods Ingredients. They published their findings in the International Dairy Journal. Holly Giles, a PhD researcher at Reading and the study's lead author, says protein drinks often have taste and texture problems that make them hard to swallow and finish. She describes it as a real problem for many people, whether they are trying to build muscle or simply keep their strength as they age.

Whey is a dairy-derived ingredient found in protein powders and nutritional supplements, and it is valued for the quality of its protein. The researchers say its sensory drawbacks, including thickness, bitterness, and chalkiness, can discourage regular use even for people who would benefit from more protein.

The study focused on one whey protein, alpha-lactalbumin, which is widely used in nutritional products and infant formula. Using a specially designed filtration process, the team concentrated it to more than twice its usual level, then tested how the result affected taste and texture.

In sensory testing, the modified whey produced a smoother drink. Participants reported less friction in the mouth and better texture characteristics than with standard whey products. In plain terms, the drinks felt less rough and went down more easily.

There was a catch. The enhanced samples also developed stronger bitter and peppery flavours. The scientists first suspected the protein itself. Further analysis showed otherwise: the culprit was minerals that had become concentrated during manufacturing. The team then adjusted the filtration method to remove those minerals. The result kept the smoother texture and tasted similar to conventional whey protein.

The researchers see the payoff reaching beyond gyms. Protein supports muscle mass, helps recovery after illness, and contributes to strength and mobility, and its importance grows with age. Yet many older adults struggle to get enough because they dislike how supplements taste or feel. Better-tasting drinks, the researchers believe, might encourage more people, older adults in particular, to use protein supplements when needed.

Giles says the team now has a much clearer picture of how both the proteins and the minerals in whey shape the way it tastes and feels to drink. Further research, she says, could improve protein drinks and make them a more appealing option for people wanting more protein. The researchers say additional work is still needed, but the findings give manufacturers clear guidance on improving drinks without compromising nutrition. Whether any manufacturer adopts the approach is the thing to watch.