Formulating with Proteins: Processing and Flavor Challenges

Spray drying whey protein at a lower pH and higher solids content results in lower flavor intensitities.

February 23, 2017Global Food Forums, Inc.The following is an excerpt from the “2016 Protein Trends & Technology Report: Formulating with Proteins,” sponsored by Arla Foods Ingredients, Amco Proteins, Givaudan, Orochem Technologies, RiceBran Technologies and Synergy. 

The amount of protein has no impact on sweet taste perception in neutral pH, ready-to-mix protein beverages. However, changing from a liquid to a solid at the same protein load did increase the level of sweetener needed. Understanding the factors that influence protein flavor will allow the formulator to optimize flavor in the finished product. [For a larger PDF of the chart, click on image.]

Protein is in high demand by consumers, and the flavor of protein ingredients is vital to product success. A recent conjoint survey of 440 consumers at NCSU revealed the attributes consumers seek include the label claim, protein type, protein amount, sweetener and metabolic benefits. Different clusters of consumers are searching for different attributes.

In consumers who regularly consume protein beverages, whey protein is the most desired protein, followed by milk protein, said MaryAnne Drake, Ph.D., Professor of Food Science at North Carolina State University, in her 2016 Protein Trends & Technologies Seminar presentation titled “Formulating with Proteins: Processing and Flavor Challenges.” These consumers seek products with 20 or 25g of protein. They are searching for naturally sweetened products, as well as products that offer satiety and great taste.

All protein sources do not taste the same. “Principal component biplot analysis by a trained panel reveals that [even] the same ingredient from different suppliers does not taste the same,” said Drake. This is true for all types of protein ingredients. As protein content increases, protein flavors increase in intensity. This is true for both dairy and soy proteins, and these protein ingredient flavors carry through into the finished product.

Proteins with the mildest flavor profile are preferred by consumers. Labeling that says a product contains higher levels of protein improves acceptability, but label claims are not as important as actual flavor.

Challenges differ, depending on the protein ingredient and application. Lipid oxidation and sulfur degradation products are (both detrimental to flavor). Different lipid oxidation values translate to different flavor perception, as well as to different functional properties—including heat stability and foam stability. Longer storage increases lipid oxidation for both whey and milk proteins, said Drake. Maillard reactions also play a role in beverages and increase at higher storage temperature and with higher lactose content.

In whey obtained from cheese, the cheese-making process, the whey manufacturing process and the final product processing all impact shelf stability and flavor of the whey. When the manufacturer is aware of potential issues, they can control and minimize flavor impact.

Spray-drying influences flavor of high-protein dairy products. In the spray-drying of whey ingredients, both a lower pH and higher solids result in lower flavor intensities. Instantized protein ingredients have a shorter shelflife, because lecithin is readily oxidized. Storage time and temperature also impact functional properties, especially for milk protein ingredients.

Food and beverage manufacturers are under pressure from consumers to produce products with natural sweeteners as part of the demand for clean label products. The primary natural, non-nutritive sweeteners in use today are monk fruit and stevia. Increasing protein levels yielded little impact on sweet taste.

Drake and her group use various methods to evaluate sweet taste. Magnitude Estimation Scaling (MES) is used to determine iso-sweet concentrations of each sweetener to sucrose. The Time Intensity (TI) method is an assessment of the intensity of a single attribute, such as bitter or metallic, over time. In the method Temporal Dominance of Sensations (TDS), panelists evaluate multiple attributes at once and select the dominant attribute. TDS shows the sequence of dominant sensations rather than intensities. In the final method, Temporal Check-All-That-Apply (TCATA), panelists may select and deselect various attributes over a period of time. This allows one to track how a product’s sensory characteristics evolve.

“Formulating with Proteins: Processing and Flavor Challenges,” MaryAnne Drake, Ph.D., Professor of Food Science at North Carolina State University,