The effect of addition of osmotic substances on the retention of selected micro‐ and macroelements in hydrothermally processed Brassica vegetables

The purpose of the study was to determine the effect of NaCl and KCl on the retention of some micro‐ and macroelements in hydrothermally treated broccoli, Brussels sprouts, and cauliflower. The following brines (0.0, 0.5, 1.0, 2.0, 3.0 g/100 g) were applied for boiling. The dry matter content (10.2–16.0), process yield (85.8–124.8), content of minerals: Na (241.5–72,989.3), K (24,184.4–112,831.5), Ca (1,202.5–5,339.5), Mg (981.5–2,402.1), Mn (13.6–89.8), Zn (28.4–137.8), Fe (101.8–402.3), and Cu (2.5–7.3) were determined. Minerals retention was also calculated. The type and concentration of salt were strongly correlated with the losses of mineral components during hydrothermal treatment. Vegetables prepared in NaCl solutions were able to preserve more micro‐ and macroelements as compared to KCl, and its optimum concentration was 1%. The highest reduction in microelements during thermal processing was observed for cauliflower. PRACTICAL APPLICATIONS: Vegetables are a good source of a many valuable nutrients, but their retention level in processed product is strongly related to the method of preparation. The most common way of preparation is to boil them in water, or saline solution applied in order to improve organoleptic properties. Usually, NaCl is used as flavor enhancer. Unfortunately, some health‐related issues arose around application of this salt, so the use of its replacers is an interesting option. This research provides detailed information about retention level of micro‐ and macroelements in Brassica vegetables prepared for consumption by traditional boiling with special emphasis paid to type and dose of applied salt. The results indicated at sodium chloride applied at 1% dose to be optimal in achieving maximum level of elements retention in boiled Brassica vegetables.