An approximate inverse recipe method with application to automatic food analysis

We propose a method for automatically determining the amount of each ingredient used to prepare a commercial food using the information provided on its label. The method applies when no part of any ingredient is removed in the preparation process and as long as we can collect the nutrition data (e.g., from the USDA Food Database) for at least some of the ingredients. Using this information, we first find a set of initial minimum and maximum bounds for each ingredient amount. Then we improve these maximum and minimum bounds using an iterative method. The resulting bounds on the ingredient amounts can then be used to estimate the nutrient content of the food. We tested this approach for estimating the phenylalanine content of various commercial foods. Phenylalanine is an amino acid that must be carefully monitored when treating patients with the metabolic disease phenylketonuria (PKU). Our numerical tests indicate that the accuracy of our method is within an acceptable range (10mg Phe) for most of the foods we considered. We implemented a web-based application of our proposed method for public use. Our method should be applicable to the estimation of nutrients involved in the management of other medical diets.