Dairy Proteins vs. Plant Proteins: How Do They Compare?

When making decisions on developing food products, especially those fortified with protein, there are many factors to consider. Factors like: what will the finished product be? What is the desired protein content? What is the desired shelf life? What is the target pH? Does this product require heating, and if so to what temperature? Does this product need to be vegetarian? Vegan? What allergens are allowed to be present? There’s never a shortage of questions that need to be answered. With the current trend towards plant-based nutrition, including plant-based proteins, how do they stack up when compared to gold standard dairy proteins? Let’s take a deep dive in this blog entry.

Nutritional Completeness

Proteins are categorized as either complete or incomplete, chiefly based on their amino acid composition. In fact, proteins that contain the “nine” essential amino acids are considered to be “complete.” Amino acids leucine, isoleucine, valine, threonine, tryptophan, histidine, methionine, phenylalanine and lysine are all essential, meaning that the human body cannot assimilate these indispensable nutrients. All animal proteins contain all nine essential amino acids – this includes milk, milk proteins and anything derived from milk. However, nearly all plant proteins lack one or more amino acids that make it incomplete, except for soy protein. In most cases plant-based proteins need to be combined with others in order to “compliment” the amino acid profiles. A classic combination that works to complete proteins is rice with legumes.

Vegetarian Compliance

Both dairy and plant-based proteins are vegetarian compliant. However, when developing products for vegetarians it’s important that developers look at the completeness of the proteins. Vegetarians, while they typically consume less overall protein than their meat-eating counterparts, are also at a high risk of protein malnutrition, mostly due to incompleteness of protein. This is one major advantage that using dairy protein immediately helps developers overcome. The only issue where dairy proteins cannot be used would be for vegan food products – this is where a good working knowledge of protein completeness, including Protein Digestibility Corrected Amino Acid Score (PDCASS), plays an integral role in ensuring vegan products have nutritionally complete proteins.

Sensory Advantages

Dairy proteins have major sensorial advantages over their plant-based counterparts. Dairy proteins have a very clean, neutral and mild milky flavor whereas plant-based can be grassy, earthy and have bean-type flavors. This turns into developmental obstacles, often requiring flavor maskers and additional flavoring agents to overcome this sensory objection. Using dairy proteins comes with far less obstacles in flavoring products. 

Development Advantages

It’s critical to consider the texture of the final product and how any added protein will invariably have an impact. Key protein attributes to consider when selecting your protein are solubility in water and optimal pH range of the protein. Protein solubility is directly related to attributes like grittiness – dairy proteins are notoriously smooth and creamy, whereas plant proteins often fall out of solution and have gritty, off-pleasing mouthfeels. Using plant-based proteins often requires the use of extra stabilizers and hydrocolloids to achieve desired mouth feel, which is directly related to a proteins ability to solubilize in water.

Cost Considerations

As an ingredient the protein component is likely the most expensive ingredient (per pound) of most formulations. Dairy proteins have been processed and refined for over five decades, whereas plant proteins (outside of soy protein), have a comparatively shorter history. Plant proteins also carry more manufacturing steps in order to clarify and isolate the protein, only adding to the cost. Because of the longer history in manufacturing, more in-depth knowledge of function and flavor, dairy proteins are pound for pound the best choice for any non-vegan products.

Ultimately, when it comes to fortifying a food item with protein there are many factors to consider, as presented above. When it comes to the overall sensory experience, though, dairy proteins reigns superior. With overall better solubility, cleaner taste profile and long-term presence in the food industry, dairy proteins will always be the best option in all cases but for vegan-style products.