Yogurt is a much-loved food around the world, not only for its unique flavor but also for its many health benefits. But how do you ensure that yogurt remains fresh and healthy for consumption with a mouthfeel appreciated by the consumer even in the total absence of fat? That’s where milk proteins come into play.
Milk proteins are an important ingredient in the production of yogurt. These proteins are made up of two main components: casein and whey proteins. Casein is the major component of milk protein and accounts for approximately 80% of total. Whey proteins, on the other hand, represent the remaining 20% of milk proteins and contains a number of minor proteins.
But what is the role of milk proteins in the production of yogurt? Milk proteins play an important role in stabilizing yogurt. In fact, when yoghurt is produced, there is a coagulation of the milk proteins, which form a gelatinous structure which gives the product its creamy and compact consistency, while the specially modulated thermic processes denature the whey proteins, developing the right degree of gelling.
However, not all milk proteins are created equal in terms of their ability to stabilize yogurt. Casein, for example, is particularly important for the stability of yoghurt, as it coagulates stably at acidic pH. In addition, casein is able to absorb water and maintain its gelatinous structure, which contributes to the stability of the yogurt.
Whey, on the other hand, contains minor proteins that contribute greatly to the stability of the yogurt, although not necessarily in the natural 80/20 ratio of casein to whey protein. The recalibration of MPC 85 with WPC 80 (whey protein concentrate) or WPI 90 (whey protein isolate) by increasing the percentage presence of WPC in the stabilizing mix makes the final rheology of the yogurt very different depending on the choices made upstream. The selection of WPCs (native or denatured) also has an important impact on the finished product.
Scientists have long studied the effect of milk proteins on the stability of yogurt. A 2014 study published in the journal Food Hydrocolloids showed that adding milk protein to milk before fermentation can improve yogurt stability. In particular, the addition of casein and WPI led to a higher viscosity and stability of yogurt compared to milk with no added protein.
In addition, scientists are working to develop new yoghurt production techniques that use modified milk proteins to improve yoghurt stability and texture. For example, a 2018 study published in the LWT-Food Science and Technology journal showed that adding GM milk proteins can improve yogurt stability and final product texture even at lower than standard addition rates (which is around 1.5%).
In conclusion, milk proteins are an important ingredient in the production of yogurt, contributing to the stability and consistency of the final product. Going from a 4% total protein (with the addition of 1-1.5% protein powder mix) to a 6/7% total protein value, you can go from a soft and creamy structure of the typical low-fat yogurt to the solid structure of a Greek style yogurt. Researchers continue to study the role of milk proteins in yogurt production and to develop new techniques to improve the quality and stability of the finished product.
In addition to their ability to stabilize yogurt, milk proteins also offer numerous health benefits. Milk proteins are an important source of essential amino acids, which are essential for the growth and maintenance of muscles, bones and skin. Additionally, milk protein is also a source of calcium and B vitamins, which are important for bone and nervous system health.
However, it is important to note that not all milk proteins are suitable for all people. Some people may be intolerant to milk proteins or may have allergies to milk proteins. In these cases, it’s important to consult a doctor or dietician to determine the best food options.
In summary, milk proteins play an important role in the production of yogurt, providing stability and consistency to the final product. Researchers continue to study the role of milk proteins in yoghurt production and develop new techniques to improve its quality and stability. In addition to their ability to stabilize yogurt, milk proteins also offer numerous health benefits, such as the supply of essential amino acids, calcium and B vitamins.
