August 25, 2008
Mathematical modeling of the evolution of three national cuisines suggests that today's culinary tastes are largely the same as they were about 100 years. The idiosyncrasies of British, French, and Brazilian cooking have remained largely intact, despite many other cultural changes in those countries over the years. We are what our ancestors ate.
Osame Kinouchi, Adriano J. Holanda, Antonio C. Roque, Rosa W. Diez-Garcia, and Pedro Zambianchi of the University of S?o Paulo came to this conclusion by researching recipes and ingredients from the medieval cookbook Pleyn Delit as well as several editions of more modern volumes: The New Penguin Cookery Book, Larousse Gastronomique, and Do?a Benta. Their results appear in the paper "The Non-Equilibrium Nature of Culinary Evolution," published in the New Journal of Physics.
The researchers examined the cookbooks, using the number of ingredients in dishes and the number of recipes published in each cookbook as variables. The authors discovered that one important factor that influenced national cuisines is the "founder effect." In biology, the term refers to the loss of genetic diversity when a new colony is established by a small number of individuals from a larger population. Traits that happen to dominate among the individuals play a disproportionately large role in the new colony. Applied to foods, the founder effect may explain why idiosyncratic ingredients continue to be part of national cuisines.
In three editions (1946, 1969, and 2004) of the Brazilian cookbook Do?a Benta, they found that the rank and importance of an idiosyncratic ingredient such as chayote, for instance, remained much the same over the years. The prevalence of certain improbable local ingredients, the authors noted, are like frozen "cultural" accidents.
The researchers also discovered that the statistical hierarchy of ingredients in each country's cookbook can be represented by Zipf's law: the frequency of each food item being inversely proportional to its rank in the frequency table. The authors found that this statistical distribution holds true for each cookbook, with the idiosyncratic ingredients having higher positions in the national lists. By comparing ingredients with similar rankings across the cookbooks, the authors concluded that national menus evolve in similar ways.
So, next time you're enjoying an English breakfast, an Aussie BBQ, an American hamburger, a German sausage, or a Canadian pancake, consider the evolutionary reasons for what you're doing.