So what’s in a flavor? Taste and smell are intertwined; if you block your nose and taste slices of raw potato, apple, and parsnip, you will not be able to taste the differences between them. Lest you conclude from this experiment that taste has the upper hand in our experience of flavor, consider that human tongues are covered with ~5,000 taste buds, each bud containing between 50 and 100 taste receptor cells capable of detecting one of five (or six, or seven…) tastes, while the olfactory membrane of the upper nasal passage has 10 million to 20 million receptor cells, with more than 1,000 types of odor receptor cells capable of detecting 10,000 different smells. Not that numerical superiority is necessarily indicative, but it does appear the sense of smell is more finely tuned than that of taste; just as the dark-adapted eye can apparently detect a single photon, the (human) nose can detect a single atom of sulfur. And the canine sense of smell is reputed to be 10,000 to 100,000 times more sensitive than human olfaction, so you’d do well to have some consideration the next time you buy dog food.
Beyond taste and smell, there is ‘somatosensation’, instrumental in generating the sense of texture and also responsible for sensations relating to temperature, irritation and pain. And numerous studies have indicated that appearance can affect the way in which flavor is perceived. A classic experiment here involves giving a wine expert white wine colored red with a flavorless colorant -upon which you’ll generally get a description as chock full of irritating red wine adjectives, as the wine expert generally is of himself.
In any case the take home here is that flavor is actually a combination of smell, taste, texture, appearance, and temperature, a fact not lost on the aforementioned Ben-Shitrit and his startup Redefine Meat. Their approach is to tackle the issue of texture with the 20th century’s premier solution-looking-for-a-problem, the 3D printer.
Redefine concentrates on providing the inhomogenous texture by 3D printing muscle, fat, and blood components through nozzles, layer by layer.
The figure above is a ‘pixel map’, showing a cross section of a Redefine Meat slab of steak, which in a sense has transformed food into text in a twist of lingua-gustatory legerdemain. In any case the letters stand for:
M: Muscle or protein component, comprising wheat, pea, potato and other sources of protein.
F: Fat, a solidified vegetable shortening derived from palm oil.
B: Blood component, made of starch and beet coloring.
Variant ingredients include other proteins (such as coconut and other plant sources, insects, algae, fungus, bacteria), other fats (variou splant butters and oils, and other lipophilic materials), albumen, and natural flavors.The protein fibers can be aligned by various methods such as extrusion and shearing.
The end result is low in fat, low in cholesterol, and low in sodium. Ben-Shitrit says including vitamin B12 (deficient in many vegetarian/vegan diets) as an additive is possible but not being done at the moment as the main audience is meat eaters and not vegans -who dont like it anyway as ‘its too meaty’.
The main differentiator for Redefine Meat is the the texture; they have separated the confounding issues of texture, flavor, and flavor-delivery, and feel that with a superior texture and better flavor delivery, they can provide an overall flavor experience that competes favorably with real meat.
The 3d printer is in a sense the perfect way to provide the texture needed for steaks – the directionality of fibers running lengthwise down the steak extrusion axis, are a key contributor to texture, and there is no other way currently available to produce such fibers within homogeneous structure to mimic the fibrous nature of real meat.