Show Me the Whey: Concentrates vs Isolates vs Hydrolysates

By Monica Mollica.  Whey protein is the highest quality dietary protein source. No wonder it is a very popular protein supplement. I often get questions about what the difference is between the different whey protein powders that we can find on the market, and which of them is “best”. We have whey protein concentrates, whey protein isolates, micro-filtered whey protein isolates, ion-exchange whey protein isolates, and hydrolyzed whey proteins. Let’s get it straight once and for all.


whey-proteinWhey protein is one of two the major milk protein (the other being casein). Whey is separated from milk, and advances in processing technology (such as ultrafiltration, microfiltration, ion-exchange and reverse osmosis) have resulted in development of several different finished whey products1-11.

Whey protein concentrates, reduced lactose whey, whey protein isolates and hydrolyzed whey products are now available on the dietary supplement market. Each whey product varies in the amount of protein, carbohydrate (lactose), fat, minerals and specific bioactive proteins like alpha-Lactoglobulin, beta-Lactoglobulin, immunoglobulins, glycomacropeptide, bovine serum albumin, lactoferrin, lactoperoxidase) 7, 10, 12.


An overview of all the benefits of whey protein compared to other proteins like casein, egg and soy is an article on its own. Here I will briefly outline some of whey’s beneficial effects.

Whey protein is a rich source of highly bioavailable essential amino acids (especially leucine) 13-15. In fact, whey protein has been singled out as the ultimate source of protein on the basis of its excellent amino acid profile and digestibility 13, 16. In addition, whey protein has several other interesting effects that are especially relevant for athletes and physically active people alike.

Whey protein has been shown to increase glycogen stores in muscles and the liver, when compared to a casein-based diet containing an identical amount of carbohydrate 17. Whey protein is also a rich source of the sulphur containing amino acid cysteine 18, 19. This is noteworthy because cysteine is the crucial limiting amino acid for glutathione synthesis in the body 20-23, and dietary cysteine is considered to be a rate limiting substrate for the synthesis of glutathione 24. Glutathione is a potent antioxidant and is also necessary for lymphocyte proliferation and immune function 20-22, 25, 26. Without getting too much into details, there are also indications that increased levels of glutathione (by changing the so called redox state) can alter gene expression in a way that promotes muscle growth 27. It has actually been shown that consumption of whey protein concentrate results in higher levels of glutathione in tissues 28, 29, and that the immuno-enhancing effect of whey protein to a large extent can be ascribed to its ability to increase glutathione levels 24.

A very interesting study compared supplementation of 20 g whey protein concentrate (see below for more info about whey protein concentrates) per day with supplementation of 20 g casein per day, for three months 19. The results showed that supplementation with the whey protein concentrate significantly increased lymphocyte glutathione levels with over 35%, and also improved peak power and 30 second maximal work capacity 19. There were no changes observed in the casein group. In addition, the subjects who had supplemented with the whey protein concentrate (but not casein) experienced a decreased percentage body fat while maintaining their body weight 19! These results are certainly of relevance for athletes and physically active people who want to improve their health and get in shape.


Whey protein isolate has the highest protein concentration (90-95%) and contains very little (if any) fat, lactose and minerals. Whey protein concentrate has a protein concentration ranging from 25-89%. Most whey protein concentrate products have a protein concentration of 80%. Whey protein concentrates contain some lactose, fat and mineral. Another major difference between whey protein isolates and whey protein concentrates is that whey protein isolates are lactose free and a more expensive.


Ion exchange is a processing technology that is used to concentrate the protein content in the powder. Protein powders with the very highest protein contents per gram are ion exchanged isolates. However, this type of processing has serious drawbacks in that it literally wipes out all the valuable and health promoting subfraction peptides like alpha lactalbumin, glycomacropeptides, immunoglobulins, and lactoferrin, which are naturally found in whey. Instead it contains a high amount of beta-lactoglobulin which can cause allergies.


There are several different types of micro filtrations technologies. They are all used with the purpose to enrich (or concentrate) various subfractions from the whey.

The popular micro filtrations technologies are Cross Flow Micro filtration (CFM®) ultra filtration (UF), reverse osmosis (RO), dynamic membrane filtration (DMF), ion exchange chromatography, (IEC), electro-ultrafiltration (EU), radial flow chromatography (RFC) and nano filtration (NF).

The micro filtration techniques allows for the production of powders of high quality (undenatured) protein with very high protein contents (>90%). Micro filtered when proteins retain important subfractions, and are low in fat and lactose, so they are definitely worth their higher price.


Then there is also hydrolyzed whey protein (also called hydrolyzed whey peptides). When a protein is hydrolyzed is means that it, by technological processes, has been split to smaller chains of amino acids, called peptides 16, 30-33. The hydrolytic process mimics our own digestive actions; thus it can be said that hydrolyzed protein is a predigested protein. Hydrolyzed proteins contain mostly di-peptides and tri-peptides, and are absorbed more rapidly than free-form amino acids and much more rapidly than intact (non-hydrolyzed) proteins 34-46.

Consumption of whey protein hydrolysate in post-exercise (and before strength training workouts) drinks is preferred because it results in a faster increase in blood amino acid concentrations and a higher insulin response during a 2-3 h period than does intact protein 47-49. The simultaneous increase in blood amino acids and insulin levels in turn significantly promotes muscle protein synthesis and inhibits muscle protein breakdown 50-58.

It is especially interesting that consumption of protein hydrolysate solutions (that also contain 15 g glucose) result in peak blood insulin concentrations that are two and four times higher than after the ingestion of milk and glucose solutions (15 g glucose in water), respectively 49. This despite the fact the milk dose in that study contained nearly three times more carbohydrate 49.

Thus, when one consumes protein hydrolysates in post-exercise drinks (and pre resistance exercise) one can create a powerful response in blood amino acids and insulin levels without having to ingest large amounts of carbohydrates and unnecessary calories. Another practical advantage is that one can ingest a protein hydrolysate-containing supplement immediately after exercise without becoming bloated and not excessively suppressing appetite, so one can eat another meal sooner, possibly optimizing the post-exercise “anabolic window”. Have you been frustrated over protein powders that clog your shaker? Then you have an additional reason to get a whey protein powder with hydrolysates because the hydrolysates increase the solubility of the product 32.

Clearly, hydrolyzed whey protein is the most popular protein hydrolysate among athletes. However, there are also casein hydrolysates and hydrolysates from other proteins available in dietary supplements.


So to wrap it all up: if you’re lactose intolerant, chose whey protein isolate. If you can tolerate small amounts of lactose, don’t bother too much with whey protein isolates; they are not worth the premium price. Instead choose a whey protein powder that is based on whey protein concentrate (containing at least 80-85% protein). Whey protein concentrates are not only cheaper than whey protein isolates but also contain more bioactive and health promoting substances.

Try to find a whey protein concentrate powder that has some hydrolysates mixed in it. It is true that hydrolysates are more expensive than concentrates, but they (in contrast to isolates) are worth their price. Hydrolysates will not only simultaneously increase amino acid availability and insulin to your muscles (and thereby maximally stimulate muscle protein synthesis and inhibit muscle protein breakdown), but will also make the powder easier to mix without causing lumps in your shaker. Practical and effective! Also, pick a product that is low in carbs and sugar.

Now you know what to look for in a whey protein product.


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About Monica Mollica >

  Monica Mollica has a Bachelor’s and Master’s degree in Nutrition from the University of Stockholm, Sweden, and is an ISSA Certified Personal Trainer. She works a dietary consultant, health journalist and writer for, and is also a web designer and videographer; Monica has admired and been fascinated by muscular and sculptured strong athletic bodies since childhood, and discovered bodybuilding as an early teenager. Realizing the importance of nutrition for maximal results in the gym, she went for a major in Nutrition at the University.  During her years at the University she was a regular contributor to the Swedish bodybuilding magazine BODY, and she has published the book (in Swedish) “Functional Foods for Health and Energy Balance”, and authored several book chapters in Swedish publications. It was her insatiable thirst for knowledge and scientific research in the area of bodybuilding and health that brought her to the US. She has completed one semester at the PhD-program “Exercise, Nutrition and Preventive Health” at Baylor University Texas, at the department of Health Human Performance and Recreation, and worked as an ISSA certified personal trainer. Today, Monica is sharing her solid experience by doing dietary consultations and writing about topics related to bodybuilding, fitness, health and anti-aging.