What if one of the sophisticated analytical tools in food science is already in your mouth? This article delves into the fascinating world of taste perception, exploring how the human tongue outperforms modern technology in decoding the complex language of flavor. From supertasters to highly trained sensory panels, discover why our ancient sensory organ remains at the cutting edge of culinary analysis and product development
We constantly judge our food. Every time we indulge in a meal or sip a drink, we instinctively evaluate its taste, flavor and texture, mouthfeel and overall sensory profile. But can our tongue truly serve as a reliable analytical instrument for discerning these sensory experiences? It turns out that our tongue and nose remain the most dependable tools for this task. Despite advances in technology and analytical methods, sensory evaluation continues to rely on actual tasting as a fundamental tool for taste assessment. There is no measuring tool good enough to create, evoke, or quantify the same responses as the human sensory system.
The human tongue
The human tongue is equipped with thousands of taste buds (papillae), each detecting the five basic tastes: sweet, salty, sour, bitter, and umami. These taste buds send signals to the brain, allowing us to perceive and differentiate various tastes. Contrary to popular belief that each area on the tongue feels a different taste, receptors for all five tastes are found wherever there are taste buds across the entire tongue, with some areas more sensitive to certain tastes than others. In fact, each taste bud evaluates all five tastes.
Considering the limited capacity of our tongue to discern only five primary tastes, how do we then account for the variety of other flavors we perceive? While taste indeed relates to the sensations detected by the taste buds on the tongue, the broader spectrum of sensory experiences falls under the umbrella of flavor. Flavor, unlike taste alone, includes a rich interplay of taste and aroma. Take, for instance, the experience of indulging in a scoop of strawberry ice cream. While the sweet taste registers on the tongue, it's the delightful aroma of strawberries that fills our sense of smell. Together, the sweet taste and strawberry scent integrate to form the unmistakable flavor of strawberries.
Flavor technology can trick your palate
In our sensory system there are sensory interactions between tastes and between the senses. Given the close relationship between our sense of taste and aroma, flavor technology presents an interesting avenue for manipulating our palate and potentially aiding in sugar reduction efforts within food products. For instance, certain flavors, such as strawberry and vanilla, are known to evoke associations with sweetness and can help boost the impression of sweetness in the brain. Through a careful composition of sweet flavor ingredients that are incorporated into food and beverage products, a sensory melody is created that mimics sweetness without the need to add or increase the sugar content.
Sensory sensitivity is often genetic
Individuals exhibit varying degrees of sensitivity to tastes and flavors, a phenomenon influenced largely by
genetic factors that dictate the amount of taste buds on the tongue. Individuals with plenty of taste buds are
often classified as supertasters, while individuals with fewer taste buds are deemed less sensory sensitive.
Supertasters, constituting roughly 5-10% of the population, possess an enhanced ability to detect small
nuances in taste and flavor profiles. Conversely, approximately 10-15% of individuals are classified as nontasters, indicating a diminished sensitivity to taste stimuli. The remaining 80% fall into the category of medium
tasters, exhibiting a moderate level of sensory sensitivity. Interestingly, supertasters may exhibit pickier eating
habits, while non-tasters demonstrate a broader acceptance of flavors, consuming a wide array of foods without
particular preference.
Based on these abilities, we can categorize tasters on a spectrum ranging from subjective to objective
assessment. At one end of this spectrum are consumers with low sensory sensitivity who provide subjective
feedback based on their preferences and perceptions of a product's appeal. These consumers represent the
target audience, reflecting typical consumption habits and preferences. Conversely, at the opposite end of the
spectrum lies the expert panel tasked with objective measurements, like a measuring instrument. These tasters
possess high sensory sensitivity and extensive sensory memory, coupled with rigorous training and calibration.
Unlike consumers, their role is not to indicate their preferences but rather to provide precise evaluations, such
as characterizing the sensory profile of a product.
Building a sensory expert panel
By selectively recruiting individuals with exceptionally high sensory sensitivity, i.e. supertasters, and providing
them with specialized training, it becomes possible to assemble a sensory expert panel as a tuned measuring
instrument. This panel serves as a reliable analytical tool for obtaining objective sensory assessments. This tool
is objective and unbiased towards personal flavor preferences. Indeed, the questions the panel is asked are not
whether the tasted sample is tasty but rather objective questions on the sensory profile as well as comparisons
to other samples.
The screening tests for the sensory expert panel involve comprehensive assessments of the tasters' sensory
sensitivity, focusing on their ability to discern slight differences, maintain consistency, and retain sensory
memory. These tests adhere to ISO standards, which are internationally recognized guidelines aimed at ensuring
consistency, quality, and safety across diverse industries and sectors.
Following the screening process, the selected tasters undergo training and calibration. Various training methods
are employed, all with the central objective of establishing a uniform language, adopting consistency in team's
rankings, and refining accuracy in the identification and characterization of products. The training includes
aligning sensory vocabulary among panel members to build sensory profiles for different products. This involves
standardizing terminology to ensure that each member interprets and describes sensory attributes in a
consistent manner. A crucial aspect of the training is to enhance the uniformity of team rankings. The training
and calibration of the expert panel are essential steps in ensuring the reliability and validity of sensory
evaluations.
