2. Materials and methods
2.1. Material and juice preparing
Two kilograms of red grape (Alphonse Lavallée, Vitis vinifera,
South Africa) (including berries and stems) was pressed in a vertical
laboratory hydraulic press (REUS, P = 200 bars, Contes, France).
Four hundred grams of press cake was collected and put directly in
the microwave reactor to extract a red microwave juice (Fig. 1). IJ
was prepared by mixing Nj (86%) with MHGE (14%) which corresponds
with the proportion of extracted juices (Table 3). Samples
of three juices were freeze-dried before analyze.