Variations in Major Nutrients and Minerals in Swedish Foods: A Multivariate, Multifactorial Approach to the Effects of Season, Region, and Chain

Fifteen food items were collected from three main purchase chains, in four geographical regions/cities in Sweden during 4 seasons of 1 year, amounting to 48 test samples per food. The foods were analyzed for moisture, ash, nitrogen, fat, calcium, phosphorus, iron, sodium, and potassium. An extensive exploratory investigation was performed to screen the material. The objective was to assess representative mean values for each food and analyte, and to assess the magnitude of the variations from different sources like region, season, and chain. A combination of principal component analysis and analysis of variance was used to elucidate the influence of these factors and the interactions. Due to interactions between region and season, these two sources were combined to the “occasion” source. No systematic variations were seen between the chains, hence this source was regarded a mere purchase variation. The occasion-variations were, with a few exceptions, smaller than the purchase variations and were in some instances not possible to separate. The smaller variations due to occasion were regarded as due to efficient distribution of foods over the country during the whole year.