They reported that hydrolyzed whey protein after lactic acid modification demonstrated superior digestive tolerance in vitro and resulted in a 20% increase in leucine content.
Human tests revealed that 10% supplementation “achieved statistically significant muscle-building effects compared to conventional whey protein at equivalent doses,” they wrote in the journal Food Production, Processing and Nutrition.
What is hydrolyzed whey protein after lactic acid modification?
Whey protein is a popular supplement consumed for muscle protein synthesis and other health benefits such as management of weight, blood sugar, and cholesterol.
However, long-term supplementation may cause adverse gastrointestinal effects such as bloating and diarrhea, particularly in individuals with lactose intolerance.
Hydrolyzed whey protein has undergone enzymatic hydrolysis, breaking down long protein chains into smaller peptides, making them easier for the body to absorb.
Hydrolyzed whey protein after lactic acid modification, also referred to as lactylated hydrolyzed whey protein, goes one step further by treating the hydrolyzed whey protein with lactic acid, resulting in additional benefits.
These benefits include faster absorption, requiring fewer digestive enzymes and minimal pancreatic stimulation. Compared to whey protein, hydrolyzed whey protein after lactic acid modification has a higher leucine content, which can promote muscle protein synthesis.
Study details
The researchers evaluated the nutritional and anabolic potential of hydrolyzed whey protein after lactic acid modification, as well as its practical application.
They aimed to characterize the amino acid profile in comparison to standard whey protein and assess its digestion using in vitro methods. They also examined improvements in skeletal muscle using mice and human subjects.
The 90-day human study involved 12 adults over 30 years of age who consumed whey protein or hydrolyzed whey protein after lactic acid modification at a dose of 800 mg/kg body weight per day.
The researchers measured anthropometric and physiological parameters, and analyzed muscle tissue at baseline and the end of the study.
They made some chemical modifications to the whey protein to explore its application potential and reported that the water- and oil-holding capacity of lactylated whey protein indicated it had theoretical potential for use in the baking or yogurt industry.
The researchers wrote, “hydrolyzed whey protein after lactic acid modification (wpel) had more peptides compared with whey protein, which led to being absorbed easily.”
“What needs to be paid more attention to was the content of leucine (Leu*) of wpel increased by nearly 20% compared with the control, which showed its potential to enhance muscle protein synthesis via promoting protein synthesis and inhibiting its degradation,” they added.
The findings also showed that wpel “enhances muscle protein synthesis by promoting the expression of p-S6K and p-mTOR,” and showed positive effects on muscle fibers “even at a 10% dosage”.
Participant tests indicated that the 10% wpel group “demonstrated superior enhancement in grip strength, BMI, muscle mass, and body fat percentage,” compared to control.
Noting the study’s lack of direct exercise evaluation, the researchers noted that their evidence “supports wpel primarily as a functional nutrient for anabolic signaling activation” and that further trials are needed to assess its sports nutrition potential.
Source: Food Prod Process and Nutr 8, 41 (2026). https://doi.org/10.1186/s43014-026-00387-8 “Effects of hydrolyzed whey protein after lactylation on muscle protein synthesis.“ Authors: H. Zhang et al.
