With so many types of proteins available on the market it can be hard to know which one you should buy. The honest truth? The answer is different for everyone. Your biggest purchase drivers (ie. price, food sensitivities, added ingredients, flavor) will factor into the best protein for you. I want to educate you on the different options so that you can make the best informed decision for yourself.
I'm going to talk about how protein is extracted, the % concentrations of various sources, the protein digestibility score (PDCAAS), price, and flavor.
How Protein is Isolated
Protein sources that are found in shake beverages are purified from various plant and animal sources. Animal sources typically come from milk, eggs, or animal bones in the form of whey, egg albumen, and collagen. Plant sources can come from virtually any plant. Common sources are soy, pea, rice, hemp, and oat.
Depending on the characteristics of the protein (ie. amino acid composition, solubility, heat stability), different extraction methods are utilized (ie. salting out, isoionic precipitation, HIP entanglement ligands). Different protein extraction methods can result in different flavor profiles, solubility, and various other sensory attributes.
Based on a proteins characteristics, some are more easily extracted than others. Whey and soy are easier to extract and concentrate, therefore isolates can reach up to 90% protein. But proteins such as almond or oat may only be concentrated to 50% protein or less. Another reason some proteins are extracted more easily is because the methods have become better understood, researched, and developed over time. Newer protein sources like almond and oat may reach higher levels of concentration over time as methods improve.
Isolates vs Concentrates
Isolates are further purified than concentrates so they have a higher protein content. For example, whey protein concentrate typically contains 80% protein, but whey protein isolate contains 90% protein. To go from 80-90% protein, further processing is required. The additional processing and smaller volume result in higher prices.
Protein Digestibility Correct Amino Acid Score (PDCAAS)
Proteins are evaluated using Protein Digestibility Corrected Amino Acid Score (PDCAAS). It's based on the amino acid requirements of humans and their ability to digest it. The highest a protein can score is 1.0 and it means that after digestion of the protein, it provides 100% or more of the essential amino acids.
Essential amino acids cannot be synthesized by humans so we need to ingest them in our diet. These amino acids include: Histidine, Isoleucine, Leucine, Lysine, Methionine, Phenylalanine, Threonine, Tryptophan, and Valine.
There are several types of protein powders that are lacking certain essential amino acids or are very low in some of them. This is why you often see plant protein blends that combine 2 or more protein sources. The amino acids that are lacking in one source, can be made up for in the other resulting in a PDCAAS of 1.0.
Just because a PDCAAS score is low, does not mean it's bad. It's just an incomplete protein. Protein powders are consumed along with a regular diet to get more protein or to have as a snack. You can make up for the lack of certain amino acids in your protein through other foods in your diet. For example, collagen does not contain tryptophan, therefore its PDCAAS is 0. This does not mean you shouldn't consume it. It still contains the other 8 essential amino acids and you can get tryptophan from fish, eggs, milk, soy, nuts, and seeds. As another example, beans are low in 5 out of 9 essential amino acids, which is why they're often paired with rice in dishes.
Whey proteins are typically the least expensive because they are easiest to produce and widely available. Newer, niche plant proteins are usually some of the most expensive for the opposite reasons. Soy protein is probably one of the least expensive plant proteins on average since it's been around the longest and as other sources become more popular, they may become less expensive as well. However, I've seen whey proteins that are $15 and some that are $50.
The extraction method as I mentioned above can play a part in the price. The methods that lead to cleaner flavor profiles and better solubility can be more expensive. The additives can influence price as well. Natural flavors and sweeteners are more expensive than artificial ones. Proteins purchased from value stores (Walmart, Aldi) will be less expensive than small health food stores because of their distribution and bulk production.
Each type of protein varies in flavor. Drinking plain, pure protein with no added flavors or sweeteners can be difficult for some people. Whey has one of the cleanest profiles because (as I've mentioned before) the methods of extraction have improved. It still can have a distinct barny, cheesy flavor to it. Pea and hemp protein tends to taste very grassy or earthy and gritty, though extraction methods are improving for pea.
Whey protein has the most added flavor varieties of any other protein. Chocolate, vanilla, and strawberry are standard, but I've seen Cookies n' Cream, Pumpkin, Fruit Loops, Matcha Mint, and many more. Most other sources come in plain, chocolate, and vanilla with a few other options here and there. Vanilla is a mild flavor and does little to cover up off notes of certain proteins.
Every type of protein comes with pros and cons. This information is designed to educate you on the different options available. I myself typically drink whey protein because the most important factors for me are taste and price and I don't have dietary restrictions. Check out the chart below and let me know which protein source you would choose in the comments!