The liver oil of hammer head shark [Sphyrna zygaena (L.)] has been extracted by the radio heaters.
The operating frequencies were 13 megacycles in the case of Test 1, 2 (Fig. 1) and 78, 55 megacycles in the case of Test 3, 4 (Fig. 2).
The vitamin A content of the dropped out oil was lower than that of the remained oil in the cooked liver. Its data are shown in the following tables (Table 1, 2, 3 and 4).