What Is Whey Protein Hydrolysate?

What is Hydrolyzed Whey Protein? What is Whey Protein Hydrolysate?

What is Hydrolyzed Whey Protein?

One form of whey protein powder that seems to fluctuate in popularity with every new marketing approach is hydrolyzed whey protein, also known as whey protein hydrolysate (WPH).

Far from a nutrition panacea, for specific circumstances we cover in detail in this article, the overall realized-nutritional value can be improved by enzymatic hydrolysis of proteins and lactose.

Another way of communicating this is to say hydrolyzed whey for some individuals can enhance the bioavailability and thus increase the nutritional benefits of the whey protein.

Pronounced "hy·dro·lyze" /ˈhīdrəˌlīz/ - "Hyrdolyze" is a verb that means "to break down." In chemistry, to hydrolyze something means to solicit a reaction using water to break or metabolize bonds.

What Does Hydrolyzed Whey Protein Mean?

Hydrolyzed Whey Protein is a subset of whey protein isolate.

As marketing buzz phrases go, the caveats describe hydrolyzed whey protein as partially or extensively hydrolyzed, broken down, and or predigested whey protein isolate (WPI).

What is Hydro Whey?

HydroWhey® is a registered word mark protecting a hydrolyzed whey protein product name [13]. 

Hydrolyzed Whey Protein vs. Whey Isolate

To justify the lavish price tag, the often stated advantages of this particular subset of WPI that draws in the eager consumer include the following.

  • Easier on Digestive System
  • Faster Absorption
  • Higher Bioavailability
  • Hypoallergenic - Less likely to trigger allergic reactions

For the sake of this article, let's assume we are discussing actual hydrolyzed whey protein and not the marketing gimmicks that surround fraudulent products.

We are here to support our community of dairy protein fanatics in learning the truth about dairy processing and, in this case, WPH; this article will cover only the facts and provide details that matter.

In stark contrast to information on so many supplement sites online about Hydrolyzed Whey Protein Powder, we will provide the details paired with adequate justification for our findings.  

Important Consideration: 

We know that every individual has a unique genetic tendency to develop allergies, disease, asthma, etc. We also understand we know very little about the dominant factors that would otherwise allow nutritionists to sufficiently predict immune responses to food.

Despite the data (statistically sound studies) suggesting that WPH has inherent advantages for consumers with heightened immune responses, everyone is different, and the factors contributing to your response thresholds are ever-changing and therefore up to you to listen to your body.

Note to Consumer -

In the USA, given the lack of regulatory enforcement by the Federal Trade Commission (FTC) on whey protein or dietary supplement marketing claims in general, as you can imagine, brands make all kinds of claims about why their whey protein tubs are better than the competition.

The reality is that unchecked pop-up brands use words strategically woven in basic scientific concepts with the intent of consumer conversion via pragmatic inference.

Essentially these brands use the average consumer's primal attraction to gain an edge in the space of muscle recovery and repair to their advantage and go on to sell the notion that WPH delivers nutrition faster and more efficiently.

Luckily for the consumer, the most significant eCommerce marketplaces online, such as Amazon, are now screening supplement brands to provide a primary backstop meant for consumer safety. The hope being as time progresses, the regulations begin to meet the demand for transparency in marketing [1].

Hydrolyzed Whey Protein Explained

As you may already understand, proteins are large peptide structures built from smaller individual amino acids.

AT AGN Roots we often get into discussion addressing the specific structures that form an intact, undenatured, and complete protein.

The image below (click) provides a little more clarity as to what these structures look like.    

Whey Protein Structures - Explained

When proteins enter the gastrointestinal tract, specific enzymes begin to cleave away at the bonds giving structure to the peptides. As the bonds begin breaking down, the particle sizes of the peptide structure become increasingly optimal for absorption by the intestine.

The main fundamental difference between Whey Protein Isolate and Whey Protein Hydrolysate is the initial state of the protein as its ingested.  

Hydrolyzed Whey Protein Difference

The fundamental difference giving WPH the marketing benefits that convert millions of sales per year stems solely from reducing peptide sizing compared to the other mainstream forms of whey (WPC & WPI).

The desired particle size of the proteins that make up whey protein hydrolysate depend on the parameters of the enzymatic hydrolysis process; these parameters include -

  • Ultra-Heating 
  • pH Adjustments
  • Addition of Enzymes (enzymatic hydrolysis)

    Does Hydrolyzed Whey Protein Reduce Allergic Responses?

    Various studies suggest that the relationship between molecular dimension (peptide size & weight) and protein allergenicity (allergenic determinants) is direct and positive [2]. Less size equates to fewer determinants- So what do we mean by "determinant?"

    Allergenic determinants are particular features on the surface area of the protein structure that combine with complementary-shaped antibodies during an immune response [4].

    The idea behind WPH is that if allergy sensitivities occur as a function of a specific surface area feature or structural protein fold, by reducing the protein structure via hydrolysis below a threshold that triggers the immune response, an individual can safely consume the protein and associated nutrients.

    In layman's terms, this means that if you are allergic to bovine milk protein, hydrolyzed whey may provide a solution that advances the protein past the point of contention with your immune system and without the misery of the sensitivity symptoms.

    Note: The aforementioned reduction in allergic response specifically refers to a milk protein allergy. This would not apply to a lactose sensitivity unless the enzymes also denatured the lactose structures.

    Does Hydrolyzed Whey Get Absorbed Faster?

    The absorption rate of whey protein hydrolysate has become the primary marketing point of hydrolyzed whey protein. This advantage to hold truthful relies heavily on two assumptions -

    1. Science shows that hydrolyzed whey protein is absorbed faster than unhydrolyzed whey protein isolate.
    2. The difference in absorption rate between hydrolyzed whey protein IF faster than unhydrolyzed whey protein isolate makes a beneficial difference versus splitting hairs.

    Addressing the first assumption, the latest sports science not funded by brands pushing their WPH concludes compelling opposition to the belief the WPH is better absorbed than intact protein structures [10]. The referenced study reports that intact whey protein fosters a more rapid absorption rate of crucial amino acids than the compared hydrolyzed whey protein.

    In addition, another study comparing amino acid absorption rates between participants ingesting either WPI or WPH on an empty stomach concluded no significant rate of amino acid appearance differences in the bloodstreams between the participants regardless of whey protein form.

    In summary general hydrolysis of whey isolate does not significantly impact absorption kinetics [11].

    The most notable and registered clinical trial (last updated 2020) also concludes that hydrolyzed whey protein and surrounding benefits are indistinguishable from whey isolate. The study's metrics fully represent benefits such as anabolic potency and efficacy for soliciting overall muscle protein anabolism and recovery [12].

    Milk Protein Allergies: Casein vs. Whey

    There may be better solutions for a consumer choosing to purchase WPH, with the driver being reduced allergy potential. In general, whey proteins, more so than casein, induce stronger systemic allergic reactions on exposure due to the rate at which whey is so rapidly absorbed [5].

    Learn More: Lactose Sensitivity Vs Milk Protein Allergen
    Learn More: Casein Protein Explained

    What is Enzymatic Hydrolysis?

    This process in which a dairy protein processor treats whey protein isolate with specific enzymes to break it down, mimicking a natural digestive process, is called “enzymatic hydrolysis.”

    Enzymatic Hydrolysis is the process that WPI undergoes to create Hydrolyzed Whey Protein. Discussed more in the following section; Protease is the most common enzyme used in protein hydrolysis.

    The addition of protease enzymes to a whey protein structure will trigger the degradation and ultimate destruction of carboxylic acid-based bonds (peptide, ester, and amide bonds).

    How is Hydrolyzed Whey Protein Made?

    Whey Protein Hydrolysates are created with the addition of a few steps when making whey protein isolate.

    Prior to filtration and spray drying, liquid whey is collected in a vat and prepared for enzymatic hydrolysis. The process at a high level is as follows - 

    1. pH is adjusted from ~5.0 to 7.0 using a strong base (caustic soda or NaOH)
    2. Protease or other proteolytic enzymes are added
    3. The solution is incubated for 20-30 min @ 50°C (the pH will drop during hydrolysis)
    4. pH is re-adjusted to 7.0 using a strong base (NaOH).
    5. The hydrolysate is then heated to 85°C for 5min to inactivate the enzyme and to arrest further hydrolysis.

    Protease Enzyme - Protease is a ubiquitous enzyme and catalyst for proteolysis. Proteolysis is the structural reduction of protein into smaller polypeptides. If the whey hydrolysis process is not stopped at 30 minutes or less, proteolysis would completely break down the proteins into single-form amino acids.

    How Much of the Whey Isolate is Hydrolyzed?

    The degree of hydrolysis is defined as the percentage of peptide bonds cleaved and is a function of the base (NaOH) consumed during the incubation period. After the time is up, an acidic solution indicates a high percentage of hydrolysis.

    Note: Products that state "100% Hydrolyzed Whey" is a scam and are typically the same brands that claim "100% Grass-Fed Whey." At most, for sports nutrition, whey protein isolate is hydrolyzed to 15%. 

    There are several scientific methods to determine the percentage of hydrolysis in whey protein. The most common is called the pH-stat method and is indirect; however, it provides an accurate estimation [9]. The pH-stat method depends significantly on the following factors -

    • Type of hydrolytic enzymes used
    • Size of the hydrolyzed peptides
    • Reaction temperature

    Why Does Hydrolyzed Whey Protein Taste Bad?

    Hydrolyzing whey protein for sports nutrition is a double-edged sword. On one edge, the benefit of consuming a less disruptive dairy protein on the stomach is excellent, while on the other, the smaller the peptide structures, the greater the bitterness profile. The "bad" taste is a combination of maskers and flavors designed to hide the intensity of single-form amino acids.

    During hydrolysis, a higher concentration of enzymes produces a greater concentration of smaller peptides or isolated single free-form amino acids [6]. Specific amino acids, when released from the broader structure, influence the bitter taste receptors more than others and include -

    • Proline
    • *Valine
    • *Leucine
    • Phenylalanine
    • Tryptophan

    *Branched-Chain Amino Acids - You may notice that when buying single form BCAAs, they are always intensely flavored with a citrus base like blue razz, lemon ice, and sour apple. Intense flavor systems are used to mask the bitterness from the single form Valine and Leucine BCAAs.

    Once cleaved from the parent structure, the bitterness intensity of the smaller peptide structure or individual amino acid stems from its newly acquired ability to engage with our mouth's bitter taste receptors (T2Rs)[7].

    The introduction of bitterness might not sound too terrible, especially if intolerance via an allergy is hanging in the balance. However, for a brand selling WPH, the final product must speak to a broader population than those with severe dairy protein sensitivities. The business driver to reach a broader market is why brands use high-intensity super sweeteners, masking agents, salts, stevia, etc.

    Is Hydrolyzed Whey Protein Bad For You?

    Theoretically, hydrolyzed protein contains the same benefits or more as the less processed forms of whey protein, WPC, and WPI. However, there are a few nuances to consider regarding typical setbacks of Whey Protein Hydrolysate in the space of sports nutrition. 

    The primary reason "unflavored," "naked," "plain," "raw" Hydrolyzed Whey is rarely marketed or available for sale is that it is unbearable in taste and requires flavor masking.

    The Enzymatic Hydrolysis process (even partial) yields an extremely bitter powder which creates an incentive for all kinds of undesirable ingredients to make their way into the product - 

    • Maskers
    • Sweeteners
    • Rich Indulgent Flavor Systems 
    • Additives (Gums, Super Sweeteners, Salts) to Compensate 

    Does Hydrolysis Impact Nutrients of Whey Protein?

    Yes, studies show that whey protein's biological value decreases as the degree of hydrolysis increases [8]. This relationship explains why the percentage of hydrolysis is typically limited to around 5%. The 5% hydrolyzed point for whey protein represents the diminishing returns marker in referencing nutritional and biological value.

      Is Hydrolyzed Whey Protein "Denatured Whey?"

      Yes. Essentially hydrolyzing whey protein is the same concept as denaturation; this is why you won't see hydrolyzed whey protein making claims such as "Undenatured" or "Cold-Processed." Part of the hydrolysis process is terminating the enzyme activity by the use of heat.

      To learn more about the circumstances when denaturation results in bioavailability losses and when denaturation is simply a critical process on the path to digestion, please take a gander here -

      Learn More: Whey Protein Bioavailability
      Learn More: Whey Protein Denaturation
      Learn More: Cold-Processed Grass-Fed Whey Protein

      Partially Hydrolyzed Whey Protein - Explained

      The only available Hydrolyzed Whey Protein for sale is limited to "partially" hydrolyzed at concentrations between 2-15% because nutritional efficacy and the benefits of the whey protein nutrients decreases and the degree of hydrolysis increases.

      The method and severity of hydrolysis significantly impact the clinical efficacy, allergen response threshold, and nutritional benefit of the whey protein. Cow's milk used to make whey protein powder is only and always classified as partially hydrolyzed based on the percentage of small peptides per total protein basis [3].

      Does Hydrolyzed Whey Contain Lactose?

      The process of protein hydrolysis has no impact on lactose concentration. Hydrolyzed whey does not contain less lactose than a whey protein isolate.

      Hydrolyzed whey protein, by definition, impacts the whey protein structures. To reduce lactose in whey protein hydrolysate or make claims to that selling point, a specific enzyme that targets the lactose structure is required. However, basic science will not stop the nutrition bloggers of today promulgating false content that WPH somehow is more inherently lactose-free than Whey protein Isolate.

      If the operation is set up already for proteolysis, adding lactase enzymes into the mix only takes time and knowledge. Lactase enzymes serve as catalysts for the lactose hydrolysis process.

      Lactase works by breaking the disaccharide into individual monosaccharides via metabolizing the glycosidic bonds. Lactose is a disaccharide made up of galactose and glucose monosaccharides, bonded together via β-1,4-glycosidic bonds.

      Hydrolyzed Whey Protein Vs. Whey Isolate

      By Weight  Hydrolyzed Whey Isolate Whey Isolate
      Protein > 90% > 90%
      Fat < 1.0 % < 1.0%
      Lactose < 1.5% < 1.5%
      Biological Value Less More
      Taste Unpalatable - Bitter Sweet Fresh Dairy
      *Absorption Rate Fast Fast
      Protein Allergies Better for Protein Sensitivities Normal
      Bioavailability Same Same
      **Lactose Allergies Same Same
      Price $$$ $


      *The difference in absorption rate of amino acids into the bloodstream is negligible between all forms of whey (WPC / WPI / WPH).

      **Lactose hydrolysis or removal is a separate process.

      Is Hydrolyzed Whey Protein Powder Worth It?

      Yes, it can be an excellent resource for a specific individual who otherwise can not digest dairy protein precisely because of a dairy protein allergen or sensitivity.

      As far as the mainstream athlete or intense fitness goer - Our stance is that whey protein isolate represents the best of all aspects of sports nutrition.

      Any differences in absorption speed or insulin spiking profiles are considered negligible and take a backseat to the price and taste, which are the kickers for our preference. 

      [1] Inc., Amazon. “Dietary Supplements - Amazon Policies.Amazon, Goettsche Partners, 2011, https://sellercentral.amazon.com/gp/help/external/55N3JF2WQS7RVNE.
      [2] Vandenplas, Yvan et al. “A perspective on partially hydrolyzed protein infant formula in nonexclusively breastfed infants.” Korean journal of pediatrics vol. 62,5 (2019): 149-154. doi:10.3345/kjp.2018.07276
      [3] Salvatore, Silvia, and Yvan Vandenplas. “Hydrolyzed Proteins in Allergy.” Nestle Nutrition Institute workshop series vol. 86 (2016): 11-27. doi:10.1159/000442699
      [4] Ghosh, Bikash C et al. “Enzymatic hydrolysis of whey and its analysis.” Journal of food science and technology vol. 54,6 (2017): 1476-1483. doi:10.1007/s13197-017-2574-z
      [5] Roth-Walter, F et al. “Pasteurization of milk proteins promotes allergic sensitization by enhancing uptake through Peyer's patches.” Allergy vol. 63,7 (2008): 882-90. doi:10.1111/j.1398-9995.2008.01673.x
      [6] Ghosh, Bikash C, et al. “Enzymatic Hydrolysis of Whey and Its Analysis.Journal of Food Science and Technology, Springer India, May 2017, https://www.ncbi.nlm.nih.gov/pubmed/28559606.
      [7] “Bitterness: Perception, Chemistry and Food Processing, First Edition.” Edited by Michael N. A. Eskin and Michel Aliani, Wiley Online Library, John Wiley & Sons, Inc., 24 Mar. 2017, https://onlinelibrary.wiley.com/doi/book/10.1002/9781118590263.
      [8] Farup, Jean et al. “Effect of degree of hydrolysis of whey protein on in vivo plasma amino acid appearance in humans.” SpringerPlus vol. 5 382. 31 Mar. 2016, doi:10.1186/s40064-016-1995-x
      [9] Rutherfurd, Shane M. “Methodology for determining degree of hydrolysis of proteins in Hydrolysates: a review.” Journal of AOAC International vol. 93,5 (2010): 1515-22.
      [10] Farnfield, Michelle M et al. “Plasma amino acid response after ingestion of different whey protein fractions.” International journal of food sciences and nutrition vol. 60,6 (2009): 476-86. doi:10.1080/09637480701833465
      [11] Power, O et al. “Human insulinotropic response to oral ingestion of native and hydrolysed whey protein.” Amino acids vol. 37,2 (2009): 333-9. doi:10.1007/s00726-008-0156-0
      [12] Moro, Tatiana et al. “Whey Protein Hydrolysate Increases Amino Acid Uptake, mTORC1 Signaling, and Protein Synthesis in Skeletal Muscle of Healthy Young Men in a Randomized Crossover Trial.” The Journal of nutrition vol. 149,7 (2019): 1149-1158. doi:10.1093/jn/nxz053
      [13] TESS Hydro Whey Nutritionals, Glanbia. “Trademark Electronic Search System (Hydro Whey).” Trademark Electronic Search System (TESS), United States Patent and Trademark Office, 30 July 2014, tmsearch.uspto.gov/bin/showfield?f=doc&state=4805:zp9dwr.2.2.
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