Cups of yogurt seldom have the same texture on the day of manufacturing and after about 45 days of shelf life.
Variables influencing texture
Dairy products start with a milk base, which is comprised of fats, proteins, carbohydrates, minerals and a plethora of micronutrients. Each component possesses a unique chemistry that may lead to interactions with added ingredients and influence texture. The task of building and maintaining texture in dairy products depends on three primary criteria. All must be considered together.
“First is the chemistry, or composition, of the dairy system,” Ms. Klockeman said. “Next is how the product changes during processing. And last is the selection of hydrocolloid system. All three influence final product texture and stability.”
Hydrocolloids are a category of ingredients that influence the texture of dairy products by binding water in the system. They are a group of polymers — polysaccharides, such as fibers, gums and starches, as well as proteins — and are characterized by the ability to form viscous dispersions or gels by binding water. The function is alluded to in the name, where the prefix “hydro” means water and “colloid” means a gelatinous substance.
Hydrocolloid suppliers typically have a tool box of ingredients. They may help save time and prevent problems by selecting the best ingredient and correct variant for a specific application.
“Often a supplier will suggest a blend of ingredients that will work better than single ingredients,” Mr. Hopkinson said.
Hydrocolloid suppliers typically have a tool box of ingredients to aid with texture development.
That blend is often very product specific. To the point that even a different flavor of ice cream, for example, may require a different hydrocolloid system.
When we think about the broad range of dairy products, and the many variations within each category, e.g., reduced-fat, no-added-sugar, high-protein formulations, each has unique challenges and varying degrees of difficulty in maintaining texture targets during shelf life. Further, what’s desirable texture to one consumer may be offensive to another.
Hydrocolloid systems allow formulators to address specific textural challenges. They also allow a formulator to manipulate texture to achieve different product consistencies. By increasing the hydrocolloids in a drinkable yogurt, the same base can be packaged into a cup product. But too much hydrocolloids may have a negative impact on texture.
“Overly stabilized dairy products can be pasty and starchy in the mouth and mask flavors,” said Nesha Zalesny, technical sales manager, Fiberstar Inc., River Falls, Wis. “For yogurts, this means less of that tart bite that is expected.
“Another example is with chocolate ice cream. A good texture will give a clean flavor release while still contributing to the melt characteristics. You want the ice cream to taste like chocolate but also not melt all over the place during the eating experience or develop large ice crystals a day after the carton is opened.”