Protein has long been recognized as the building block of muscle tissue and is required to repair tissue damaged during strenuous exercise. Protein drinks are an efficient and economical means of consuming protein on a daily basis, especially for weightlifters and athletes who must maintain a high protein diet. Many protein drinks combine a range of supplements into one mixture, while others offer a very pure form of whey, soy, or casein protein. When choosing the right protein drink, most people look to what type of protein is used, the taste, and how well it mixes.
The word protein itself is somewhat of a loose term, as it encompasses a virtually limitless number of individual molecule chains. Proteins, peptides, and polypeptides, which share similar and often overlapping definitions, are all made up of amino acids. Amino acids are the actual molecules the body uses to build and repair muscle tissue. There are 22 types of amino acids required by the human body, eight of which are essential, meaning the body can not synthesize them from other sources. Essential amino acids must be obtained from food sources on a daily basis and should be included in any type of protein drink mix.
The vast majority of protein drink mixes are made from whey protein and include all 22 amino acids. The exact amino acid profile is usually listed on the container under the nutrition facts. Of the three most common types of protein — whey, soy, and casein — whey is the most commonly available due to its low production cost and desirable qualities.
Whey protein is available in two forms: isolate and concentrate. Of the two, concentrate is more common and generally contains 70-90% protein by weight with the rest constituting a variety of ingredients, including lactose, fat, sugar, and undenatured proteins. Whey protein isolate generally contains 90-96% protein by weight and does away with the majority of non-protein ingredients to create a low-calorie protein drink.
Unlike whey protein, casein occurs naturally in most dairy products. While whey protein digests very quickly, casein digests much more slowly over a period of six to eight hours. Due to the slow digestion rate of casein, it makes a great nighttime protein drink, as it provides the body with a steady protein supply during sleep. Casein protein is available in concentrates and isolates like whey, and contains many of the same ingredients.
Soy protein is derived from soybean proteins and is most commonly used by vegetarians and lactose-intolerant individuals. Soy protein is sometimes thought of as unattractive by males because it contains estrogen-like compounds found in many plants. Regardless of common misconceptions, these compounds have no measurable effect on testosterone levels in males or females due to the minute amounts found in protein drink mixes. Numerous studies have shown that even high levels of this compound have little to no effect on hormone levels and may even increase testosterone levels slightly.
Two of the most important aspects of a particular protein drink are not available on the label — taste and mixability. If a protein drink doesn't taste good, a person will be far less likely to drink it as necessary, so a good tasting mix is important. Another important aspect is mixability, or how well the powder mixes into water or milk. Many people require their protein to be spoon-mixable, meaning it can be mixed in a regular cup with only a spoon without clumping, while others use special protein drink shakers with lids and some sort of device that breaks up the chunks as it is shaken. If the protein powder clumps when using a protein mixer, it is likely a low quality protein. For a thoroughly-mixed protein drink, regardless of quality or thickness, a blender can be used.
