Piotr Gębczyński

Effect of maturity stage on the content of ash components in raw and preserved grass pea (Lathyrus sativus L.) seeds.

The grains of grass pea cultivar krab of dry matter content at the level of 26–40 g/100 g were used in the production of preserves by freezing and canning in air tight containers. The content of ash and its alkalinity and of potassium, magnesium, calcium, iron, total phosphorus, and phytic phosphorus was determined in raw and blanched material, in frozen products stored for six months and then cooked to consumption consistency, and in sterilized canned products after the same storage period. With the increasing degree of maturity the content of all the above constituents calculated per 100 g fresh matter, increased. Blanching considerably reduced the level of ash and its alkalinity, of potassium, and of phytic phosphorus. The cooking of frozen seeds and the sterilization in salty brine caused a reduction of the components analysed except for the content of ash, its alkalinity, and of calcium. In comparison with canned sterilized preserves in cooked frozen grains a higher content of all the mineral components was determined.

Zinc retention in vegetables according to the method of preparation for consumption

The aim of the present work was to evaluate the retention, the nutrient density and the recommended daily allowance of zinc in 14 common vegetable species prepared for consumption. The investigation included fresh vegetables, vegetables after traditional cooking in brine and two types of frozen products: one obtained using the traditional method (blanching–freezing–storage–cooking in brine) and the other obtained using the modified method, providing a ready-to-eat product (cooking in brine–freezing–storage–defrosting and heating in a microwave oven). A significant zinc decrease was found in most studied vegetables prepared for consumption. Application of the modified method contributed to a reduction in zinc losses in prepared-for-consumption frozen vegetables.