Posted on January 04 2018
Ben Esgro, MS, RD, CSCS
Gone are the days when whey protein was seen as a product exclusively for lifting enthusiasts. All the way from convenience stores to supermarkets, whey infused items now line the shelves and checkout counters at major retailers. Industry terms and buzz words like concentrate, isolate, instantized, hydrolyzed, ion-exchange, microfiltration, etc.… plaster the labels of products and protein marketing, but what do they really mean to you and the resulting experience of using the product? For this week’s formulation Friday, we will focus upon the five primary factors that answer the question: Why doesn’t your protein mix well?
PROCESSING OF THE WHEY
To begin the production of whey, all manufacturers must subject milk to at least some degree of processing to separate the two milk proteins, whey and casein. Adding a small amount of acid (usually hydrochloric acid) causes the casein to undergo a chemical change and fall out of solution. It can then be filtered off while the liquid whey remains. This remaining whey, after drying, is whey protein concentrate powder. Though roughly 80% protein by weight, whey protein concentrate also contains a small amount of fat, carbohydrates, and milk sugar (lactose). Because it contains more compounds which are less water soluble, whey protein concentrate is going to be the least soluble of the whey proteins and, therefore, will give you the most trouble with clumping and making a smooth mixture.
If a higher protein content is desired, whey protein concentrate can undergo further processing to create a virtually fat, carbohydrate, and lactose free protein. There are two primary methods used to create these whey protein isolates; microfiltration and ion-exchange. As the name implies, microfiltration passes liquid whey through progressively finer filters, ultimately allowing the protein and mineral salts to pass through while excluding larger, non-protein compounds. In contrast, ion exchange takes advantage of the fact that amino acids possess chemical charges (unlike fat or protein). Similar to taking advantage of charges when sticking a magnet to your refrigerator, ion exchange uses a column with charged beads to make the proteins in whey “stick”, while allowing non-proteins to pass without interaction. While both ion exchange and microfiltered whey protein isolates will differ in their nutritional compositions (differing amino acid and mineral profiles), both will have an improved mixability compared to whey concentrate.
Another type of processing which impacts the mixability of protein powders is hydrolysis, also known as whey protein hydrolysates. Hydrolysis is a process that happens during normal protein digestion in your body to break large proteins into smaller units before absorption. Hydrolysis can also be done by manufacturers using specialized enzymes to produce a “pre-digested” protein which is generally less allergenic, more easily digested, and more soluble. The downsides, however, to the use of whey protein hydrolysates are that they are more expensive and have a stronger taste and odor compared to non-hydrolyzed proteins. So, they may mix easier, but they may not taste as great.
Finally, most protein powders today utilize a process called “instantizing” which enhances their dispersion into fluids by suspending the fine protein particles in an emulsifying agent. This can be done to all of the above-mentioned whey proteins to enhance their mixability in fluids. If the label does not outright claim the protein to be “instantized”, an easy confirmation of this processing can be done by checking the ingredients. Soy or sunflower lecithin are the most common emulsifying/instantizing agents used in protein powders today.
WATER CONTENT AND STORAGE
You may have noticed the “Best By” or expiration dates printed on all your favorite supplements. Also, that many packaged goods are recommended to be stored in “cool, dry, dark places”. Why do companies do this? While supplements do have seals and barriers to the outside environment, they are not packaged in air tight containers. This means they are still exposed to a level of environmental conditions, such as humidity (moisture in the air), oxygen, and light. Clumping of powders in a container is an example of excessive environmental moisture interacting with a powder. This is why you find the desiccant packs in the jars of your dietary supplements. Not only will clumping reduce the solubility of your powders, it will also reduce the potency of your product over time. Light and oxygen, on the other hand, degrade ingredients over time. Again, this leads to reduced potency and potentially altered solubility.
AMOUNT OF LIQUID
While it may be obvious, the amount of fluid you use to mix your protein is going to determine how well it mixes smoothly into a solution. For something to dissolve in a liquid, both the liquid and solid need to be able to interact on a molecular level. Simply put, more fluid allows more probability of interaction between the protein and fluid, so, the better it dissolves. This is a key area where following label directions and formulation come into play. Typically, products are formulated for a specific sweetness and flavor at a specific fluid level. So, while watering down may enhance the mixability of your protein, it is important to also realize it will alter the flavor profile if you are going beyond the recommended liquid levels.
TEMPERATURE OF THE LIQUID
Solubility is highly dependent upon temperature. In general, the more heat you add, the more solubility is enhanced. So, if you want the quickest and easiest mixability of your protein, it will always work better in warm vs cold fluid. This is great for chocolate proteins in the winter to make hot chocolate! Remember though, too much heat will cook your protein, changing its structure and causing it to coagulate, so this is only beneficial up to a point. Unless you want protein blocks in your drink, aim for warm liquid, not hot (nothing that would burn your tongue if you drank it).
As a rule of thumb, the more ingredients your protein contains, the more difficulty you are going to have with mixability. A liquid can only “hold” a specific quantity of solids before it becomes saturated and you get sediment or undissolved chunks. While many of these ingredients may enhance the texture and consistency of your protein, they are going to make it harder to go into solution. So, less is more if you want a pure and mixable protein!
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