Messing with the Senses

I'll begin with this: the "mystery" flavor of Dum-Dum lollipops. When I was a kid, I had a theory that mystery flavor was a factory mistake. All the lollipops that accidentally made it through the assembly line uncolored were swaddled in a "mystery" wrapper, spangled in question marks like the suit of the man who helps you get free government money. Which didn't actually help me solve the problem of what flavor, exactly, they were supposed to be. I always found them off-putting -- colorless, translucent globes of indeterminacy. (Googling it now, this article claims that the mystery flavor is a mixture of two other flavors in production, the mixed-up flavors that get produced between batches in the lollipop factory.) 


Almost everyone, in school science labs, has done some variation of this experiment: sipping tiny paper cups of colorless orange soda, or Sprite tinted to look like Coke, and then trying to guess at the flavor of these uncanny concoctions. The flavor of a soft drink -- something that seemed so obvious and familiar -- is revealed to be elusive, befuddling, difficult to pin down. Is it grape? Is it orange? Is it lemon-lime? Why is it so hard to tell?

And it's not only rubes who can't tell red wine from white without looking at the glass -- this is a common incapacity, even among snobby winos.

Examples like these, of the profound effects of color on our perception and experience of flavor, are familiar to most of us now. Our present-day scientific understanding of how color is mixed up with flavor has its roots in the 1930s, when the industrialization of food systems made flavor a technical and scientific problem for food producers. Among other things, manufacturers needed ways to minimize and counteract the deleterious effects of processing on food quality; they needed standardized, stable, and consistently priced products; they needed foods with "flavor appeal" that would tempt "repeat buyers." This meant defining what, exactly, flavor is, and how it works to produce its effects. Even as chemists, food technologists, home economists, and other scientists got better at analyzing, identifying, and manipulating the molecular and material aspects of food that contribute to flavor, they recognized that flavor could not fully be described chemically, nor was it exclusively produced by the "chemical senses," taste and smell. As Ernest Crocker, who I've written about before on this blog, put it in his introduction to the landmark 1937 American Chemical Society Symposium on Flavors in Foods: "A new approach to the subject of flavor consists in attacking several of its many sides simultaneously, but especially the psychological and the chemical sides." Understanding flavor would mean not only studying its molecular aspects, but also the way perceptions of flavor were influenced by visual cues, social norms, personal history, present atmospheric conditions, and the vagaries of individual physiology. This is one of the points where two nascent fields -- flavor chemistry and sensory science -- are cross-hatched together.  

One of the first people to mess around with visual cues and flavor perception was H.C. Moir, a Scottish analytic chemist working at a baked-goods factory in 1930s Glasgow. Present-day sensory scientists cite Moir's 1936 article ("Some Observations on the Appreciation of Flavor in Foodstuffs"), published in the British technical journal Chemistry and Industry, as the first to document how the color of a food shapes our experience of its flavor. (For instance, this nifty article by Crossmodal Lab's Charles Spence touts: "ever since the seminal observations of Moir in the 1930s, researchers have known that changing the color of a food or beverage can change its perceived taste/flavour.")

Most scientists who cite Moir don't go into any detail about his experiments, and (just guessing here) probably haven't read his article. And, really, why would they? In the intervening decades, there have been dozens, if not hundreds, of studies published about the role of visual cues in flavor perception, using much more sophisticated techniques, producing much more formidable results. Scientific conventions prescribe preserving the honor of first discovery in the crowded footnotes, but there's no obligation to engage with this dustiest of data. (And Moir may not even fully deserve the credit he gets as pioneer. In his article, he credits Mr. Rendle of Chivers & Son -- a manufacturer of marmalades, fruit preserves, and jellies-- with developing the method of "testing 'palates'" that he describes.)

Stomping around in the bibliographic basement, however, can sometimes enrich our understanding of how we got to now -- the interlinked networks of interests, institutions, ideologies, technologies, materials, and living, working bodies that underlie the production of scientific facts.  

So, with all that said, who was H.C. Moir, and what exactly is his story?

It's rather difficult to find any solid information on Moir, but when he wrote his article, I'm fairly certain that he was the director and chief chemist at William Beattie, Ltd., a Scottish wholesale bakery. That is, he was not a psychologist, psychophysicist, or physiologist trained to observe and measure human sensory responses to stimuli. He was an industrial analytic chemist, and the research that he describes did not take place in the controlled setting of an academic laboratory, but rather on the factory floor, with workers in his bakery as his subjects.

Nor was Moir primarily trying to prove any basic hypotheses about the nature of sensory perception. Instead, he was dealing with a technical and commercial problem: he needed to find reliable tasters to evaluate the quality of his baked goods.

He writes: “My object in making ... these tests was to find within the factory" a group of individuals with a proven "discriminating palate... to whom questions of flavor could be referred." He wanted to have trustworthy "tasting panel" that could weigh in on new products, or detect whether something was going wrong with the production line.

And so he casts his net over the factory floor, drawing in sixty tasters -- managers, salesmen, "factory girls," bakers, "in some measure... a cross section of the consuming public" -- who are subjected to a series of tests in order to assess their sensory acuity.

Moir begins by having his subjects rank solutions of sucrose and citric acid in order of increasing sweetness and sourness. He then asks about their habits and preferences. Do you have a sweet tooth, or do you prefer savories? Do you take sugar in your tea? How many lumps? Are there any foods you particularly loathe -- olives, asparagus, pineapple?  

But the most dramatic part of Moir's investigation -- the part that still earns him citations from present-day sensory scientists -- comes when he serves up discordantly colored sweets. Recognizing that people are often "misled by their eyes" when identifying flavor, he decides to confound the senses of his subjects by serving them Chivers-brand "table jellies" -- ie, flavored gelatin, like Jell-O, I think -- in four distinct "good, true-to-type flavors," but with colors that were not typically associated with the added flavor. So:

  • Yellow Vanilla (I think we can assume that this was bright, bright yellow)
  • Green Orange
  • Amber Lime
  • Red Lemon

The tasters were assured that they were dealing with very familiar flavors -- nothing odd or exotic here -- and then asked to name them. If they really struggled to come up with anything, they were given the four possible options, and told to match them with the proper jellies.

The tasters performed terribly. Only one person out of the sixty got all the identifications right; most got fewer than half the questions correct on the test. And the guesses were all over the place. The vanilla jelly was identified as black currant, lime, apricot, lemon, orange, tangerine, strawberry, among other things. Guesses for the lime-flavored jelly included vanilla, pineapple, and apricot.   

What's more, Moir was astonished by the indignation that his tasters exhibited when told of their execrable performance: 

“Some of the least discriminating were the most dogmatic in their decisions. The majority of those who came below 50% went to great pains to assure me that they were considered by their wives or mothers, or other intimates, to be unduly fastidious about their food, and were invariably able to spot milk turning well in advance of any other member of the household.”

Some tasters insisted that their palates were fine, it was the test that was flawed. Others complained that the test was unfair to them because they personally disliked table jellies. “But of course, what I was anxious to find was those who were possessed of palates which could discriminate even that which they did not appreciate," grumbles Moir. "No one enjoyed the flavor of decomposed fruit... but on occasion one must detect, and if possible, identify it."  In other words, for Moir, a good taster and a gourmand are not the same. An accurate taster must be able to report his or her sensory perceptions without prejudice, dispassionately detecting and identifying the flavors that are present in a food regardless of personal preference.

Moir emphasized the egalitarian implications of his findings. Situational authority -- the power or expertise possessed by the foreman, the manager, the chemist -- does not confer sensory authority. Just because someone is in a position of power does not mean that he or she is "the right person to decide any point as regards the flavor of the products concerned." Indeed, Moir laments that chemists too often assume the accuracy of their sensory capabilities, with disastrous results for the business. "There is nothing to be ashamed of in the lack of a palate," he avers, "but there is something to be ashamed of in a chemist making definite statements on a subject in which he is unable to discriminate."

Even though the results of his investigation reinforce his suspicions that "in the majority of people the faculty [of perceiving flavor] was exceedingly dull," Moir counsels his fellow food manufacturers not to use the public's poor taste as an excuse to neglect the flavor of their products. Though the good tasters may be vastly outnumbered, he says, “the discriminating section of the public exercises an influence out of all proportion to its numbers on the non-discriminating section."

I originally tracked down Moir's paper because it's one of the earliest I've found that makes reference to a "tasting panel" -- a group of individuals selected for their sensory acuity, used by food researchers as a sort of laboratory tool for producing scientific information about flavor qualities. In the first twenty years after its publication, Moir's 1936 article was most frequently cited by researchers writing about techniques for assembling reliable laboratory taste panels. These studies are primarily concerned not with the operation of the human senses, but with accurately detecting and describing the qualities of foods.

The turn towards applying research about the workings of the human senses to the development of new food products would not come until at least the 1950s (at least that's what I've discovered in my research so far.)  Although sensory scientists now locate Moir at the dawn of crossmodal sensory research, reading his article, it is clear that he is not particularly concerned with the ways that multiple senses work together to produce the experience of flavor. Indeed, his color test is a way of weeding out people whose sensory judgment is deformed by visual evidence -- implying that, for him, the visual distorts, rather than contributes to, flavor. He does dish out some interesting tidbits: for instance, he observes that more intensely colored foods are often perceived to have stronger flavors -- a phenomenon that later research seems to confirm. However, he does not seem at all inclined to use this information to guide the development of baked goods -- eg, chocolate rolls that seem more richly chocolatey without any additional chocolate.  

This stands in marked contrast to trends and tendencies in the application of present-day sensory science. Charles Spence's article mentioned at the beginning of this post -- well worth reading -- reviews the manifold ways that senses other than taste and smell shape our expectations and experiences of food's flavors. Not only the color of food, but the pitch of the music playing over the speakers, the massiveness of the plate, the brightness of the overhead lights, influence our perception of the character and intensity of the taste and smell of the foods before us. This kind of thing is of real importance to food manufacturers, as it provides potential avenues for intensifying the sensory pleasures of foods while decreasing the need for costly flavoring ingredients. Spence also notes that an additional "area of intense commercial interest currently revolves around seeing whether the consumer's brain can, in some sense, be tricked into perceiving tastes/flavours without the need to include all the unhealthy ingredients that so many of us seem to crave."

So is this a perturbing manipulation of our perceptions -- turning our senses against us -- or is it a savvy application of scientific research, to the end of producing goods that can both gratify our sensory desires and satisfy our material and physical requirements (for cheaper foods, more nutritious products, more intense pleasures, etcetera)? Anecdotally, even people who are more or less okay with "processed foods" seem disturbed about this aspect of food research, which gets imagined as the hegemonic forces of big food reaching their creepy tentacles into your brain and occupying your appetites. The informed and empowered consumer, steadfastly reading labels and counting calories, dissolves and becomes a reflex machine, resistless against the compulsions of salt, sugar, fat.

One of the things I'd like to discover is where this horror story comes from. Fear of chemicals in foods has a long history, dating back to the nineteenth century, at least, and coming to the cultural forefront in various guises at specific historical moments -- for instance, in the Progressive era around the passage of the Pure Food and Drugs Act, or in the 1960s with the countercultural critique of the food industry. But I'd like to also track down the prefigurations of this fear or suspicion of food's sensory qualities, and the new tenor that fear takes when science intervenes in producing those qualities. Definitely something to think about...