Calcium caseinate

Calcium caseinate is one of several milk proteins derived from casein in skim and 1% milk. Calcium caseinate has a papery, sweet and overall bland flavor, and is primarily used in meal preparation and fat breakdown. Caseinates are produced by adding an alkali to another derivative of casein, acid casein. The type of caseinate is determined by the cation added alongside the acid casein. Other cations used to form caseinates besides calcium include ammonium, potassium, and sodium.

Calcium caseinate contains about 17% glutamic acid. Calcium caseinate is mostly composed of 3.5% moisture, 1.0% fat, 90.9% protein, 0.1% lactose, 4.5% ash, although this may vary slightly by manufacturer. Calcium caseinate is semi-soluble in water, contrary to acid casein and rennet casein which are not soluble in water. Sodium caseinate is more water soluble than calcium caseinate, due to its polarity.

Physical properties
Caseins are found in milk which is held together by colloidal calcium phosphate. Calcium caseinate is generally stable at a pH above 5.7, and appears as a milky liquid. This is unlike ammonium, potassium, and sodium caseinates, which are practically clear. At a neutral or acidic pH, casein is relatively insoluble in water, and is easily separated from other milk proteins, sugars, and minerals. Casein can be resuspended by alternating the pH levels with NaOH or Ca(OH)2, resulting in aqueous solutions of sodium caseinate or calcium caseinate. Most caseinates are capable of withstanding temperatures of up to 140°C (284°F), however calcium caseinate is influenced by heat with temperatures as low as 50°C (122°F). Calcium is a divalent cation, allowing it to form bonds with several caseinate anions. The binding of a calcium ion is able to reduce the electrostatic repulsion and induces a net attraction between caseins. This leads to the formation of several covalent bonds between caseinate anions, which can ultimately cause the cross-linked caseinate to form pockets of hydrophobic regions. Calcium caseinate forms visco-elastic suspensions which increase remarkably when increasing concentration (50–300 g L−1) and decreasing temperature(10–50 °C).

Application in food
Several foods, baked goods, creamers, and toppings all contain a variety of caseinates. Calcium caseinate's nutritional benefits include improving the structure configuration of foods; emulsifying and stabilizing fat; and enhancing foaming and foam stability. Sodium caseinate acts as a greater food additive for stabilizing processed foods, however companies could opt to use calcium caseinate to increase calcium content and decrease sodium levels in their products.

There are two Calcium Caseinate forms, spray-dried (Scaca) or roller-dried (Rcaca) which are used for multiple applications. Scaca can be found in dry milk powder, instant soups, medications, and instant coffee. It plays an important role in the conversion of fruit and vegetable juices into instant powders, instant coffees and teas, drying of eggs and dairy products such as ice cream mixes. Rcaca is mostly used in meat products and processed cheese.

At high temperatures, Scaca can decrease while there is no impact on Rcaca. Some mechanical properties such as Fibrous calcium caseinate gel shows that its structure is more anisotropic than plant-based meat analogue candidates. Its formation is strongly influenced because of its solvent isotope effect. 30% of Scaca mixed with H2O gives more anisotropic fibers. On the other hand, Rcaca results in a homogeneous gel meaning that there is no effect. This demonstrates that both Scaca and Rcaca make a significant impact in the field of food science, given that these methods are commonly used for the industrial production of food biopolymers.

Muscle mass
Caseinate, being a protein, plays an important role for muscle hypertrophy, which is the enlargement of muscle mass. Caseinate in particular has demonstrated to be more effective with this process compared to other types of proteins, such as soy- and whey-derived proteins. Consumption of caseinate leads to higher muscle weight and less fat weight gain compared to the other two proteins.

Blood pressure and insulin regulation
In addition to the impact caseinate has on the body's muscle mass, it also has shown to help lower serum TAG for those who are hypertensive. Calcium caseinate supplementation has shown improvement in several cardiometabolic risk factors, such as blood pressure, arterial reactivity, lipid levels and blood vessel function. Furthermore, Calcium caseinate can help lower central systolic blood pressure by improving endothelial function. This leads to better control of vascular relaxation and contraction, as well as blood clotting regulation, immune function and platelet adhesion.

Calcium caseinate has also significantly lower insulin compared to whey protein and maltodextrin which reflected in reduced plasma nonesterified fatty acids and was also able to induce lower postprandial TAG concentrations.