This paper is one of a series based on original research conducted by Christopher Yandle at Lincoln on the New Zealand Meat Market. In the course of this work the author conducted a questionaire survey of 300 families in Christchurch in which heads of families were asked to indicate their basic preferences for different meats, and to record their actual expenditure on meat along with family income for a given week. This paper deals at a more technical level with the analysis of this data in particular with the derivative of Engel Curves showing the relationship between consumers incomes and their purchases of meat. The subject is the estimation of Engel curves from survey data. A review is made of the appropriate economic theory, and the application of that theory to market generated data.