Variations in Major Nutrients and Minerals Due to Interindividual Preparation of Dishes from Recipes

Variations in major nutrients and minerals in dishes prepared in ordinary households were investigated. Ten families with children were asked to prepare three different dishes each, following recipes but according to their own choice regarding weighing, measuring, and flavoring. In the resulting dishes moisture, ash, nitrogen, fat, calcium, phosphorus, iron, sodium, and potassium were analyzed. Relations between analytical results and the implementations of the recipes undertaken by the families were evaluated. Variations due to determination (chemical analysis) and preparation were evaluated for each of the three dishes (ANOVA). The magnitudes of the variations were compared with other results obtained in preparations with varying degrees of standardization. Principal component analysis (PCA) was performed to find patterns in the manner of preparing dishes. The relative standard deviations (RSD) for the different dishes due to preparation were about 10% RSD for dry matter, ash, nitrogen, and phosphorus, and 20–40% RSD for fat and the minerals, except for iron in sausage stroganoff, where nearly 70% RSD was obtained. The general RSDs due to preparation were two to four times larger than those obtained in standardized preparations performed in an experimental kitchen but in household amounts, and about half of those observed when families prepared dishes in a totally optional way. In the PCA the dominant variation pattern was associated with the fat contents, although enhanced by the closure effect.