About the question "how humans come to like spices", I came across the following text, by Paul Rozin, in "Psychobiological perspectives on food preferences and avoidances", in "Food and evolution", 1987. I hope you like that text as much as I did. Best wishes, Jean-Louis [log in to unmask] --------------------------------------------------- "Chili peppers produce oral pain and, at moderately high levels, induce defensive reflexes, including salivation, running of nose, and tearing of eyes. They have been consumed in Meso-America and other parts of the New World for thousands of years and incorporated into many Old World cuisines following their discovery in the 16th century. The circumstances under which such an aversive food was rather readily adopted are mysterious, especially in light of the reluctance to adopt seemingly more nutritive and palatable products of the Americas, like corn and tomatoes. Chili peppers are among the most commonly consumed flavorings in the world and are probably eaten on a daily basis by over one-quarter of the adults in the world. My emphasis will be on the mechanisms responsible for reversal of innate aversions. However, one can hardly refrain from discussing the possible adaptative value of consuming this popular spice. Chili peppers, per unit weight, are among the best sources of vitamin A and C in the world. Capsaicin, the substance that causes the mouth burn, activates the gastrointestinal system, stimulating salivation, gastric secretion, and gut motility. The role of any of these features in the adoption of chili pepper into new cultures or the acquisition of a liking for it is not known (...) We have studied the liking for chili pepper in a Mexican highland village and in the University of Pennsylvania community. At this time we do not know how this aversion reversal occurs, but I will summarize some of its basic features, and some constraints on theories of acquisition. A basic first point of that people consume chili pepper because they like it. It is a "good taste", and according to self-reports, is rarely consumed primarily because of its anticipated effects. Furthermore, people who like chili come to like the very same sensation (the mouth burn) that initially puts people off. In a Mexican village, children in the two- to six-year-old range receive gradually increasing amounts but are permitted to refuse it when it can be removed (e.g. by omitting the hot sauce on the tortillas). They are not rewarded in any obvious way for eating it; rather they observe that it is enjoyed by their elders. By age five to eight, most children in the village were voluntarily adding piquancy to their foods; they had come to like the "hot" stuff after months to years of exposure to it in a natural family setting. (American adults sometimes acquire likings for chili peppers very rapidly, after a few experiences.) Some of the mechanisms I have discussed may be at work, with initial exposure "forced" by mild social pressure to do what other members of the family do and the fact that moderate levels of chili are cooked into some of the rest of the meal, and with the already good tastes of the main food staples. Furthermore, the salivation facilitates mastication of an otherwise rather dry and mealy diet and may enhance the flavor of the food as well. The saliva and the pepper flavor and burn added to a rather bland diet seem to improve the taste of the food significantly, explaining why the most frequent explanation for chili eating offered by Mexicans is that it adds flavor or zest to food. Two possible explanations of the acquired liking for chili (and perhaps other innately unpalatable substances) depend on its initial unpalatability. The mouth pain of chili may become pleasant as people realize that it is not really harmful. This puts the pleasure of eating chili in the category of thrill-seeking, in the same sense that the initial terror of a rollercoaster ride or parachute jumping is replaced by pleasure. People may come that there really is no danger produced by chili may cause the brain to attempt to modulate the pain by secreting endogenous opiates, morphine-like substances produced in the brain. There is evidence that, like morphine, these brain opiates do reduce pain. At high levels, they might produce pleasure. Hundreds of experiences of chili-based mouth pain may cause larger and larger brain opiate responses, resulting in a net pleasure response after many trials. (...) There are multiple routes to liking (...) In the case of chili pepper and most other likings, I am inclined to emphasize the importance of the social matrix and the valuation of the food by important others. A major role for social valuation might help to explain why non-human omnivores seem to develop acquired likings for food rather rarely, and why it is extremely difficult to get animals to liek chili pepper. A few cases of chil-liking in animals have been reporteed; however, in all such cases, the animals (chimpanzees, dogs, macaque monkeys) were adored pets in homes where chili pepper was a frequent part of the diet. Perhaps these personal domesticates participated in the human social matrix that may be so important in the reversing of aversions and the development of likings. -------------------------------- [a few pages later, about flavors] (...) Flavor principles impart a characteristic to most of the dishes in a cuisine, This culinary institution can be somewhat speculatively traced to a bit of human biology, the omnivore's dilemma. Fear and curiosity about new foods are represented in individual humans by a desire for familiarity in foods, an indicator of safety, and an opposing desire for variety and reaction against monotony in diets. Flavor principles may be a response to the desire for familiarity, since they give almost all foods a characteristic and familiar flavor. But what about the other side of the omnivore's dilemma, the desire for variety? Careful analysis indicates that the flavor of a cuisine is usually a group of flavorings that vary from dish to dish while maintaining a common identity or family resemblance. Thus, while chili pepper appears in almost all Mexican food, a wide variety of peppers with differnt flavors are used, and there is some systematic variation of these peppers from dish to dish. Similarly, the curries of any region of India are families of flavors that are mixed in varying ways in the menu cycle. In short, the practice of flavor principles can be seen to represent both sides of the omnivore's dilemma: variety within a general familiar constraint, or culinary themes and variation. This may be a case where a culinary institution can be accounted for as a transformation of a basic food selection biology."