Start with the base, not the label

A more precise masking strategy begins by changing the formulation question. Rather than asking only which protein is present, the development team must determine which sensory attribute is driving rejection in that particular system.

The first step is to evaluate the base before adding or intensifying a characterising flavour. Trained sensory assessment can establish whether the dominant issue is bitterness, astringency, metallic character, an undesirable volatile note or a combination of both. Temporal methods can be valuable as an acceptable first sip may be followed by an aftertaste that builds with repeated consumption. Instrumental analysis can then help identify volatile or non-volatile contributors, while receptor-based research can clarify how particular taste-active compounds are perceived.

This diagnostic sequence is important because sensations that consumers describe with similar language may have different origins. Bitterness from whey does not necessarily behave like bitterness from pea or soy. Astringency requires a different response from metallic taste, and a sulphurous aroma requires a different response from chalky mouthfeel. Processing also changes the target: heat, pH adjustment and storage can alter protein conformation, generate volatiles or affect interactions with other ingredients.

The formulation should therefore be assessed as a system rather than as a list of ingredients. The same protein can perform differently in a neutral dairy-style shake, an acidified clear beverage or a plant-based matrix. Masking solutions must be validated in the intended application, under the relevant processing and shelf-life conditions. Otherwise, an approach that works in a model solution may fail after thermal treatment or may create an unintended effect elsewhere in the profile.

For development teams, this translates into a staged workflow. A descriptive sensory panel can first map the intensity and timing of relevant attributes in the unflavoured base. Comparison across protein sources or suppliers can reveal whether the problem follows the protein, the process or the wider matrix. Analytical techniques, including volatile profiling, can then narrow the chemical contributors to undesirable aroma, while targeted taste and mouthfeel measurements help separate bitterness from astringency or particulate effects. The candidate masking system should subsequently be screened at more than one dosage, both before and after addition of the final characterising flavour.

Final validation must extend beyond a freshly prepared bench sample. Heat treatment, homogenisation and storage may change protein aggregation, release or generate aroma-active compounds, and alter the balance between sweetness, flavour and off-notes. Testing at the beginning and end of intended shelf life helps determine whether the solution remains effective throughout the product’s lifecycle. This evidence-led sequence reduces the risk of correcting the wrong attribute or selecting a masking level that performs only under ideal laboratory conditions.

Precision-led taste modulation

Kerry’s Tastesense™ Masking ( https://shorturl.at/7Sy6V ) approach applies advanced sensory, analytical and receptor-based science to identify the off-note driving rejection in a defined protein system. The objective is to target and modulate that unwanted note rather than mask the characterising flavour of the product.[1]

This approach is designed to create a cleaner, more neutral foundation on which the intended flavour can perform. When bitterness or aftertaste is addressed directly, a chocolate, vanilla, coffee or fruit profile does not need to work as hard to conceal it. That can help preserve flavour balance and manage cost-in-use by avoiding unnecessary increases in characterising flavour. The masking process must be tailored by protein and application. Kerry’s masking flavours are created through a 100% nature-inspired process. Drawing on more than 50 years of expertise  in dairy and protein science, Kerry combines these nature-inspired building blocks with sensory characterisation, analytical investigation and rapid in-house application testing to select and validate an appropriate solution. Repeated sensory assessment remains important throughout development; reducing one defect should not introduce another, nor should it suppress desirable flavour or disrupt sweetness and mouthfeel.

Formulators can also use Kerry’s Tastesense Masking Simulator ( https://explore.kerry.com/protein-masking-tool ) to select a protein type, identify its principal off-notes and explore potential masking solutions for the relevant region.

Precision masking is consequently best viewed as part of an integrated product-design process. Protein selection, processing conditions, stabilisation, sweetness, mouthfeel and flavour architecture must be considered together. In some cases, upstream changes to the protein or process may reduce the off-note burden before a masking solution is applied. In others, targeted modulation may allow the desired nutritional level  to be retained without distorting the finished flavour.

Designing for the whole sensory experience

As protein innovation expands, sensory performance will increasingly distinguish products that consumers try once from those they purchase repeatedly. A strong nutrition claim can encourage initial consideration, but it cannot compensate indefinitely for bitterness, drying astringency or an aftertaste that persists beyond the intended flavour.

The lesson for formulators is to resist treating protein masking as a final layer added at the end of development. Early assessment of the unflavoured base, identification of the dominant off-note and validation in the complete processed product can reduce avoidable reformulation. It also supports more disciplined flavour design: characterising flavours can express the intended profile instead of being overloaded to hide faults beneath it.

Protein does not present one universal taste problem, so it cannot be addressed with one universal masking strategy. Precision begins with understanding what the consumer perceives, when it is perceived, and which component or interaction creates it. By linking sensory evidence with
analytical and receptor-based insight, targeted taste modulation can help manufacturers build protein-forward products that deliver both nutritional value and a clean, balanced experience.

This precision-led approach is not limited to protein. Modern functional products may combine protein with caffeine, collagen, creatine, stevia, or artificial sweeteners, vitamins, minerals, and electrolytes, each introducing a different sensory challenge. Assessing the complete matrix helps formulators address layered off-notes without overwhelming the intended flavour.