The effect of freezing on mineral element content of vegetables

Abstract

The contents of six elements (Ca, Cu, Mg, Mn, Ni, and Zn) were analyzed by flame atomic absorption spectrometry in five sets of fresh and frozen products, from the same batches, of three vegetable species—artichokes ( Cynara scolimus, L.), green beans ( Phaseolus vulgaris, L.), and peas ( Pisum sativum)—in order to examine the possible changes in mineral content caused by the freezing process. The mineral content was different in the three vegetable species analyzed. The statistical study (ANOVA), indicates that though average retention percentages were lower than 100 in almost all the analyzed sets, mineral losses due to the freezing process are only significant at the 99% confidence level, in the case of Cu content of green beans and peas. Given the variability observed in the mineral content of the vegetables analyzed it seems that the mineral content via frozen vegetables is approximately the same as via fresh vegetables.