FISHERIES AND MARINE SERVICE Translation Series No. 4334 ...

(i.e. the degree of maturity) can no longer be verified in fillets, the
differentiation between mildly salted herring fillets and normal Matjes
fillets is very difficult or no longer possible at all. A typical
characteristic of unfilled herrings, however, is a high fat content of
the herring meat. Like the salt content, the fat content is easily and
accurately checked in each herring fillet or part thereof. It was
therefore logical to tie the designation "Matjes" fillet to a minimum
fat content in the herring fillet and to replace the requirement of
maturity which can no longer be monitored by a minimum fat content
although this enabled the fillets of fat or whole herrings with the re-
quired salting to be labelled as "Matjes" fillets, thus permitting a
larger quantity of herrings to be offered as "Matjes" fillets. On the
basis of our own earlier investigations which we already reported else-
where (9), it appears justified to establish for Matjes fillet and pre-
pared herring meat with appropriate labelling a minimum fat content of
15% based on the herring fillet of the raw material. Herring meat with
a 15% fat content therefore corresponds to a fat herring fillet. Further-
more, meat with this fat content can be processed for most types of pre-
parations without any restrictions or other complications. It should
be noted that with this fat content approximately 0.4% cholesterol is to
be expected in the petroleum ether extract from the edible portion of
the herring.
The results of experiments with herring fillets of various origin
and fishing seasons are compiled in Table 2. The herring oils were ob-
tained by extraction with petroleum ether from the comminuted herring
meat which had been ground up with sodium sulfate. The cholesterol was
9