NO. 2 (1921 ) REMARKS ON CANNING II3 



they resemble when completed. A harmless preservative in the 

 brine is also more important than v^^ith sardines. - • 



168. Frying. — This may or may not be practised ; if there is 

 likely to be some delay in closing and processing fish, it is neces- 

 sary to fry them in view to their sterilisation ; they are then placed" 

 out of danger and may be kept covered with oil even till next day. 

 But for ' plain mackerel ' frying is not necessary and is apt to 

 dry the fish too much ; mackerel are by nature a somewhat dry fish 

 so that care must be taken. If at all over-dried they should be 

 packed in oil or curry or marinated ; all fried mackerel are the 

 better for such packing. 



169. Packing. — The rectangular cans used at Beypore (see supra 

 paragraphs 32 — 39 s.v. ' cans ') are too small for mackerel which 

 are consequently packed in flat cylindrical cans holding 12 oz- 

 nett of fish ; these are easy to pack, close, exhaust, and process ; 

 the packed cans weigh I lb. to 17 oz. They are also packed in 

 double sized tins holding 24 to 26 oz. nett of fish ; these are very 

 good value. ' Plain mackerel ' are packed with a couple of cloves 

 and a few black peppers, but no other spice. 



Oval tins are usually used for herring and are advisable for 

 mackerel also; these are best made of the solderless pattern and 

 the Beypore cannery has the necessary dies and chucks for 

 somewhat small ovals, but these have not yet been used. 



170. Closing, etc. — These cylindrical tins are placed centrally on 

 small turn tables and the solderers seem to be more successful in 

 closing them than the rectangular tins. 



Since the cans of plain mackerel necessarily contain much 

 air (and steam when processed), it is absolutely necessary to 

 exhaust them thoroughly, so that tops and bottoms may be concave. 

 Processing should beat temperatures above 212° F. ; at Beypore 

 240° is usual and the period about 45 minutes; probably l^ to 2 

 hours at 212° will suffice, since the heat is more rapidly 

 communicated to the fish in these cylindrical tins which are not 

 very closely packed and, with the plain, non-fried mackerel, 

 contain a good deal of moisture (like plain herrings) as is seen 

 when the cans are opened. 



171. Mackerel in oil. — These are treated just like sardines in oil, 

 but must not be fried too long or at too high a temperature, 

 otherwise the flesh will become unduly dry and hard. 



