As showed by E. Engel a century ago, increasing incomes lead the households to allocate a smaller part of their budget to food expenditures. In addition, the structure of consumption is changing by the substitution towards richer products, denoted as "the quality effect". This paper aims to explain the consumption of "convenience foods", as a part of this evolution, which is assumed to be related to the time constraints imposed on households. From an analysis of survey data, the author finds a positive relationship for every income category between the consumption of "convenience foods" and the degree a household is time constrained.
