The landscape of plant-based nutrition is heavily reliant on the functional and sensory properties of protein isolates, with pea protein serving as a primary candidate for diverse food applications. When evaluating commercially available pea protein ingredients, it becomes evident that these samples can differ meaningfully in their sensory profiles, even when they are evaluated within a simplified matrix. This variability is critical because pea protein is primarily utilized as an ingredient in larger formulations rather than as a standalone final product. Consequently, the objective of sensory analysis is often centered on assessing acceptability—the degree to which a consumer can tolerate or accept the ingredient's inherent properties—rather than a narrow measure of preference.
The complexity of these sensory differences spans across four primary domains: aroma, flavor, texture, and overall acceptability. These attributes are not isolated but interact to define the total consumer experience. For example, the presence of certain off-flavors can negatively impact the perception of aroma, and the textural attributes, such as viscosity or powdery residue, can alter how flavor is perceived on the palate. The evaluation of these profiles requires a rigorous framework, often utilizing a 10-point acceptability scale. This specific scale is chosen for its reliability in differentiating unflavored proteins, where a wide diversity of liking responses is unlikely due to the absence of additive flavorings.
The systemic analysis of these proteins reveals that the "protein user type"—whether a consumer primarily consumes plant-based or animal-based proteins—does not significantly influence the acceptance of the product. This suggests a universal sensory threshold for pea protein acceptance, meaning that both plant-based and animal-based protein consumers accept similar product profiles. This finding is pivotal for manufacturers, as it indicates that the development of pea protein ingredients does not need to be segmented by the dietary habits of the target consumer, but should instead focus on the universal optimization of the sensory profile.
Consumer Acceptance Metrics of Pea Protein Samples
The assessment of consumer acceptance for various pea protein samples demonstrates a spectrum of ratings ranging from unacceptable to acceptable. A notable trend in the data is that no samples were rated as very unacceptable or very acceptable, indicating that current commercial pea protein isolates occupy a middle ground of sensory acceptability. The analysis utilized a three-way mixed model analysis of covariance (ANCOVA), which identified significant effects for both the specific sample and the individual panelist across all four measured dimensions: aroma, flavor, texture, and overall acceptance.
The disparities between samples are stark when examining specific attributes. For instance, Pea Protein B emerged as a leader in aroma acceptance, whereas Pea Protein F was viewed most unfavorably in that category. However, the same protein that excelled in aroma did not necessarily excel in flavor; Pea Protein B actually received the lowest mean acceptance ratings for flavor. This divergence highlights the multi-dimensional nature of sensory profiling, where a sample may be visually or aromatically appealing but fail to deliver a palatable flavor.
The following table provides a detailed breakdown of the mean consumer acceptance ratings across different samples and user types.
| Sample ID | Aroma (All) | Aroma (Plant-based) | Aroma (Animal-based) | Flavor (All) | Flavor (Plant-based) | Flavor (Animal-based) | Texture (All) | Texture (Plant-based) | Texture (Animal-based) | Overall (All) | Overall (Plant-based) | Overall (Animal-based) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Pea Protein B | 7.08 ± 0.17 | 7.22 ± 0.22 | 6.94 ± 0.28 | 4.45 ± 0.22 | 4.46 ± 0.32 | 4.43 ± 0.32 | - | - | - | - | - | - |
| Pea Protein F | 4.51 ± 0.19 | 4.85 ± 0.28 | 4.16 ± 0.28 | - | - | - | - | - | - | - | - | - |
| Pea Protein H | - | - | - | 7.34 ± 0.15 | 7.45 ± 0.28 | 7.22 ± 0.22 | 8.13 ± 0.14 | 8.22 ± 0.20 | 8.03 ± 0.21 | 7.31 ± 0.14 | 7.39 ± 0.20 | 7.24 ± 0.20 |
| Pea Protein E | - | - | - | - | - | - | 4.46 ± 0.19 | 4.67 ± 0.28 | 4.24 ± 0.28 | - | - | - |
| Pea Protein I | - | - | - | - | - | - | - | - | - | 4.95 ± 0.17 | 4.96 ± 0.23 | 4.94 ± 0.27 |
Sensory Attribute Analysis: Flavor and Taste Profiles
The flavor profiles of pea protein samples are characterized by a variety of specific notes, ranging from desirable nutty attributes to undesirable "off" flavors. These attributes are categorized into flavor notes (e.g., beany, grassy, cardboard) and taste/texture perceptions (e.g., bitter, salty, astringent). The data indicates that Pea Protein H achieved the highest overall and flavor acceptance, likely due to its balanced profile, while Pea Protein I was the least accepted overall.
One of the most significant challenges in pea protein sensory profiling is the presence of negative drivers. Internal preference mapping for aroma acceptance reveals that components such as barny, beany, rice, and cheesy aromas act as negative drivers of consumer acceptance. These specific sensory notes were found to be prevalent in several samples, specifically Pea Proteins A, J, H, F, I, and G.
The interaction of these flavors is complex. For example, the beany and barny flavors are often high in samples that are rated poorly. In contrast, attributes like nutty flavor are generally more accepted. The following list details the specific flavor and taste attributes identified across the samples:
- Barny flavor: A negative driver of acceptance.
- Beany flavor: A negative driver of acceptance.
- Cardboard flavor: A characteristic identified in various samples.
- Cereal/grainy flavor: A flavor profile present in the samples.
- Cheesy flavor: A negative driver of acceptance.
- Grassy flavor: A flavor profile present in the samples.
- Green pea flavor: A la characteristic of the source material.
- Nutty flavor: A flavor profile present in the samples.
- Rice flavor: A negative driver of acceptance.
- Bitter taste: A taste attribute measured across samples.
- Salty taste: A taste attribute measured across samples.
- Sweet taste: A taste attribute measured across samples.
- Umami taste: A taste attribute measured across samples.
- Astringent taste: A taste attribute measured across samples.
Detailed Taste and Texture Specifications
The tactile experience of pea protein is defined by its physical properties on the tongue and in the mouth, specifically regarding powdery sensation, residual coating, and viscosity. These factors contribute directly to the texture acceptance ratings. Pea Protein H received the highest mean rating for texture (8.13), suggesting a smoother or more pleasant mouthfeel, whereas Pea Protein E received the lowest (4.46).
The quantitative data for taste and texture reveals significant variance. For example, Pea Protein M exhibited a very high score for powdery sensation (3.15) and residual coating (2.84), which likely contributes to its specific texture profile. Conversely, Pea Protein K showed a relatively low score for astringency (0.93).
The following table outlines the measured taste and texture attributes for selected Pea Protein samples:
| Sample ID | Bitter | Salty | Sweet | Umami | Astringent | Powdery | Residual coating | Viscosity |
|---|---|---|---|---|---|---|---|---|
| Pea Protein A | 2.23 ± 0.24 | 1.70 ± 0.19 | 0.89 ± 0.18 | 1.91 ± 0.21 | 2.50 ± 0.25 | 1.76 ± 0.29 | 2.64 ± 0.20 | 2.14 ± 0.30 |
| Pea Protein B | 2.79 ± 0.30 | 1.48 ± 0.26 | 0.66 ± 0.17 | 1.85 ± 0.26 | 3.21 ± 0.31 | 1.79 ± 0.26 | 3.05 ± 0.30 | 2.01 ± 0.19 |
| Pea Protein G | 1.53 ± 0.34 | 1.94 ± 0.20 | 1.08 ± 0.23 | 1.49 ± 0.13 | 1.36 ± 0.27 | 1.64 ± 0.19 | 2.14 ± 0.17 | 0.90 ± 0.11 |
| Pea Protein H | 1.79 ± 0.28 | 2.06 ± 0.12 | 1.02 ± 0.13 | 1.65 ± 0.15 | 1.21 ± 0.26 | 1.59 ± 0.29 | 2.14 ± 0.25 | 1.00 ± 0.12 |
| Pea Protein I | 2.16 ± 0.28 | 2.10 ± 0.19 | 0.98 ± 0.12 | 1.91 ± 0.14 | 1.21 ± 0.27 | 1.31 ± 0.15 | 2.03 ± 0.21 | 1.28 ± 0.16 |
| Pea Protein J | 1.97 ± 0.24 | 2.67 ± 0.30 | 0.99 ± 0.14 | 1.47 ± 0.17 | 1.12 ± 0.25 | 1.54 ± 0.21 | 1.91 ± 0.17 | 0.84 ± 0.18 |
| Pea Protein K | 1.62 ± 0.31 | 1.69 ± 0.17 | 1.44 ± 0.17 | 1.61 ± 0.18 | 0.93 ± 0.19 | 2.16 ± 0.24 | 2.21 ± 0.22 | 1.09 ± 0.12 |
| Pea Protein L | 1.56 ± 0.19 | 2.16 ± 0.19 | 0.75 ± 0.16 | 1.83 ± 0.10 | 1.44 ± 0.24 | 1.70 ± 0.21 | 1.84 ± 0.20 | 0.86 ± 0.21 |
| Pea Protein M | 1.05 ± 0.18 | 1.87 ± 0.24 | 1.48 ± 0.26 | 1.43 ± 0.16 | 1.02 ± 0.28 | 3.15 ± 0.38 | 2.84 ± 0.32 | 0.89 ± 0.11 |
Comparative Flavor Profiling
The flavor intensities vary significantly across different protein isolates. For instance, l'existence of la "beany" flavor is a common marker of pea protein, but its intensity varies. Pea Protein B and Pea Protein A showed high levels of barny and beany flavors, which correlates with their lower flavor acceptance ratings.
In contrast, some proteins exhibited higher notes of other characteristics. Pea Protein C displayed the highest nutty flavor (2.93) and rice flavor (2.14), while Pea Protein F had the highest rice flavor (1.86). These distinctions allow manufacturers to select the protein isolate that best complements the intended final product's flavor profile.
The following table details the flavor intensity ratings for the analyzed samples:
| Sample ID | Barny | Beany | Cardboard | Cereal/Grainy | Cheesy | Grassy | Green Pea | Nutty | Rice |
|---|---|---|---|---|---|---|---|---|---|
| Pea Protein A | 2.89 ± 0.44 | 2.36 ± 0.22 | 1.23 ± 0.14 | 2.16 ± 0.31 | 2.74 ± 0.49 | 1.26 ± 0.23 | 1.91 ± 0.27 | 1.39 ± 0.20 | 1.25 ± 0.15 |
| Pea Protein B | 2.96 ± 0.52 | 2.16 ± 0.19 | 1.37 ± 0.18 | 2.79 ± 0.28 | 2.41 ± 0.42 | 1.74 ± 0.36 | 1.56 ± 0.28 | 1.79 ± 0.27 | 1.06 ± 0.21 |
| Pea Protein C | 1.31 ± 0.25 | 1.98 ± 0.14 | 1.18 ± 0.13 | 1.87 ± 0.20 | 0.82 ± 0.20 | 2.11 ± 0.21 | 2.93 ± 0.21 | 2.14 ± 0.29 | 1.18 ± 0.19 |
| Pea Protein D | 1.43 ± 0.21 | 2.61 ± 0.23 | 1.21 ± 0.20 | 1.73 ± 0.14 | 1.08 ± 0.22 | 1.59 ± 0.27 | 2.14 ± 0.23 | 1.54 ± 0.19 | 1.69 ± 0.23 |
| Pea Protein E | 1.43 ± 0.19 | 1.81 ± 0.13 | 1.86 ± 0.27 | 1.89 ± 0.10 | 0.71 ± 0.13 | 1.31 ± 0.17 | 1.82 ± 0.15 | 1.36 ± 0.13 | 1.33 ± 0.13 |
| Pea Protein F | 1.62 ± 0.13 | 2.33 ± 0.28 | 1.31 ± 0.20 | 1.65 ± 0.19 | 1.04 ± 0.19 | 1.41 ± 0.18 | 1.99 ± 0.20 | 1.15 ± 0.22 | 1.86 ± 0.14 |
| Pea Protein G | 1.33 ± 0.22 | 1.81 ± 0.15 | 1.24 ± 0.25 | 1.88 ± 0.12 | 1.35 ± 0.23 | 1.44 ± 0.20 | 1.98 ± 0.17 | 1.33 ± 0.16 | 1.64 ± 0.15 |
| Pea Protein H | 1.18 ± 0.24 | 2.10 ± 0.18 | 1.06 ± 0.20 | 1.61 ± 0.13 | 0.94 ± 0.15 | 1.14 ± 0.23 | 1.81 ± 0.13 | 1.25 ± 0.14 | 1.56 ± 0.19 |
| Pea Protein I | 1.48 ± 0.22 | 2.25 ± 0.15 | 1.08 ± 0.11 | 1.74 ± 0.19 | 1.01 ± 0.20 | 1.41 ± 0.18 | 2.03 ± 0.21 | 1.31 ± 0.15 | 1.60 ± 0.20 |
Methodology for Sensory Evaluation and Data Analysis
The rigorous nature of the sensory evaluation was ensured through a structured multi-step process. Panelists were provided with la standardized 10-point acceptability scale, which was adapted from Bekdash et al. (2020). This scale is specifically designed to provide a reliable framework for differentiating unflavored pea protein, as the primary focus is on acceptability rather than the preference of a final consumer product.
The data analysis employed high-level statistical tools to ensure the validity of the results. Descriptive analysis data were analyzed using a three-way repeated-measures analysis of variance (ANOVA), involving the panelist, product, and replicate as variables. Consumer acceptance data were handled via a three-way mixed model analysis of covariance (ANCOVA), which considered the panelist and product as within-group variables and the protein user type as a between-group variable.
To determine post hoc differences, Tukey's honestly significant difference (HSD) was applied with an alpha level of 0.05. The software utilized for these computations included SPSS version 27 (IBM, USA) for the primary statistical analyses and JMP Pro 17 (SAS Institute, USA) for the internal preference mapping. The preference mapping specifically utilized the descriptive analysis ratings and consumer acceptance scores to visualize the relationship between sensory attributes and user acceptance.
Analysis of Sensory Drivers and Consumer Impact
The internal preference mapping reveals a critical connection between specific sensory attributes and the overall acceptance of pea protein. The mapping showed that Components 1 (25.2%) and 2 (12.5%) accounted for 37.7% of the total variation in aroma acceptance. This indicates that a significant portion of whether a consumer accepts a pea protein sample is driven by a small number of sensory characteristics.
The "negative drivers" are particularly impactful. The prevalence of barny, beany, rice, and cheesy aromas in samples such as Pea Protein A, J, H, F, I, and G directly correlates with lower acceptance. For a manufacturer, this implies that reducing these specific volatile compounds is more important for increasing consumer acceptance than simply adding positive flavor notes.
The lack of significant difference between plant-based and animal-based protein consumers is a major finding. The ANCOVA results indicated no significant effect of protein user type on aroma (p = 0.79), flavor (p = 0.48), texture (p = 0.24), or overall acceptance (p = 0.52). Furthermore, there were no significant product × protein user type interaction effects across any of these categories. This suggests that the "barrier to entry" for pea protein—the inherent sensory challenges—is perceived similarly across all dietary populations.
Conclusion
The sensory profiling of commercially available pea protein isolates reveals a complex landscape of variability that has direct implications for food science and product development. The findings underscore that not all pea proteins are created equal; differences in aroma, flavor, and texture are significant and can be quantified. Pea Protein H stands out as a high-performer in flavor, texture, and overall acceptance, while other samples like Pea Protein I and Pea Protein B struggle with specific negative drivers.
The analysis confirms that the primary hurdles to pea protein acceptability are specific off-notes, particularly barny and beany aromas. The fact that both animal-based and plant-based protein consumers share similar acceptance patterns indicates a universal sensory profile for this ingredient. This allows for a more streamlined approach to ingredient selection, where the focus remains on the reduction of negative drivers and the optimization of texture—specifically reducing powdery residues and residual coatings—to improve the overall quality of the final food product. Ultimately, the ability to identify and mitigate these specific sensory deficits is the key to enhancing the commercial viability of pea protein in the plant-based market.