Casein is a type of protein found in milk and dairy products and in fact is the most prevalent protein found in milk making up roughly 80% of its content. The other predominant protein is the ever popular whey protein. Casein protein is part of what gives milk its white colour along with fat globules thanks to both compounds being large enough to reflect light. Casein is perhaps the second most popular protein in the bodybuilding and training supplement industry, and while its popularity has dipped in the past decade or so, increased studies have begun to find that casein protein might be a better option for your average trainer than whey. Just like whey proteins, there are quite a few types and forms of casein proteins, all of which have their individual benefits. This articles takes a look at some of the more prevalent types.
Casein Isolate & Concentrate
Casein protein is usually derived from milk through a process which requires a coagulant to be used. This coagulant, usually known as chymosin will precipitate and coagulate the casein protein. The whey fraction is then expelled via a process known as syneresis. This process can be completed via a variety of methods and can depend upon the amount of salt used, acidity developed, enzymes and physical disturbances. This process is usually what is involved in the cheese making process, however with casein protein supplements, the idea is to achieve as much syneresis as possible leaving a relatively pure casein. Casein proteins are rarely advertised as isolates and concentrates unlike whey protein supplements, however one would assume that it would follow the same principle in that less fat, carbohydrates and other bioactive fractions are included in the final product.
Micellar Casein & Tri-Celle Casein
Micellar Casein is a special type of casein which concentrates the micellar portions of casein. Casein proteins in general are slower absorbing, making them the perfect night time protein, however micellar caseins are considered even slower digesting and absorbing as they tend to form a gel in the stomach, making it harder for digestive enzymes to break down the molecule. Micellar casein can take anywhere between 6-8 hours to digest. Optimum Nutrition, one of the largest and most popular supplement companies in the world known for their proteins has recently also derived a Tri-Celle casein, in which they were able to combine micellar casein molecules into a form which is roughly triple the size of average casein molecules making it even slower digesting than regular micellar casein. These two types of proteins are ideal for use during the day as well as during the night, where there is a prolonged period of fasting.
Casein is naturally a very insoluble compound, which is why casein supplements often have a grainy texture when mixed in solution. As such, caseinates are often used as a primary source of casein in several products. Calcium caseinate, potassium caseinate and sodium caseinates are some of the most common types of caseinates and are created by mixing with calcium, potassium or sodium hydroxides at a high pH. These compounds result in an easier to disperse powder when mixed with liquid, giving it a smoother, finer texture – however most caseinate protein powders are still slightly grainy.
Casein Hydrolysate or Hydrolysed Casein
As with whey protein, casein protein can also be hydrolysed, which aims to improve its digestion, but also chop of the protein into smaller peptides and thus produce even more potential bioactive compounds in the form of di- and tri- peptides. The hydrolysis process also changes hydrophobic properties and structures of protein, impacting and often altering the functional characteristics of the original protein. Casein hydrolysate is produced in a similar manner to whey protein hydrolysate using enzymes to cleave specific bonds in the casein protein to create smaller proteins and peptides. Casein hydrolysate or hydrolysed casein is faster absorbing than your average micellar casein, but is still slower than whey protein. Casein hydrolysates higher in AlphaS-1 peptides have been shown to have an anxiolytic or calming effect.
Casein protein is mostly available in powder form with most of the main brands producing a casein only protein such as Optimum Nutrition Tri-Celle Casein and 100% Casein, Max’s Nitetime Protein, MusclePharm Casein and Dymatize Nutrition Elite Casein. As previously mentioned, most casein protein powders are quite grainy in texture and are also quite thick, especially with milk.
Thanks to their thick texture, casein custards have slowly crept into the market. While they can be made into your usual shakes, you can also make them into a delicious pudding like custard by using less liquid to mix the supplement. These custards are generally quite smooth compared to the shake and double as a delicious and satisfying dessert for when you have those sweet cravings.
Casein Rich Foods
Casein is naturally found in milk from a variety of animal species. So anything made from dairy tends to be high in casein such as milk, cheese, yoghurts and ice creams.