20 Trarisactions. 



'Art. IV. — The Food Values of New Zealand Fish: Part I. 

 By (Mrs.) Dorothy E. Johnson, B.Sc. in Home Science. 

 Communicated by Professor J. Malcolm. 



[Eead before the Olago Institute, 9th. December, 1019 ; received by Editor, 31st December, 



1919 ; issued separatehj, 4th June, 1920.] 



In all countries where procurable, fish should be made an easily accessible 

 article of diet — i.e., it should be both plentiful in quantity and reasonable 

 in cost ; but, so far, the greatest possible use has not been made of the 

 bountiful supply in New Zealand waters. Beyond the investigation of 

 the composition of frost-fish and oysters by Malcolm* no attempt has been 

 made to estimate the food values of New Zealand fish. 



Recognizing the necessity for the prosecution of research in the 

 Dominion, the New Zealand Government placed funds at the disposal of 

 the New Zealand Institute, which enabled that body to make a grant to 

 Professor J. Malcolm for the investigation of the chemistry and food values 

 of the New Zealand fish. This paper outlines the work done in that 

 connection. The aim has been to ascertain — 



(a.) The percentage composition of the edible portion of the fish 



investigated. 

 (6.) The caloric value of the fish (by calculation), 

 (c.) The percentage of waste in the fish as bought. 

 (d.) From the point of view of cost, to arrive at some conclusion as 



to the comparative values of the fish as an article of diet. 



Methods. 



The fish were obtained from Dunedin retail fish-dealers, with the 

 exception of one " baby " groper, which was sent from the Portobello 

 I'ish-hatcheries, and a sample each of mullet and snapper, which were 

 sent from Auckland by boat. With the larger fish, from ^ lb. to 1 lb. was 

 purchased, as would be done for home consumption. Wherever possible 

 three samples, bought at difl'erent times, were analysed, but this was not 

 always possible. 



In a few instances there is some doubt as to the exact variety of fish 

 bearing a commonly known name : e.g., " sea-bream " is applied to two 

 or three different varieties of fish,f and exact identification would have 

 been difficult owing to the fish being for the most part obtained in slices. 

 It is likely, however, that in such instances the dift'erences in composition 

 would not be very marked — probably less than the difference between 

 individuals of the same variety. 



(I.) Percentage of Edible Material and Percentage of Waste. 



Skin, bones, &c., were separated from the muscle, and the two portions, 

 edible and non-edible, weighed. The flesh was finely minced and well 



* Trans. N.Z. hid., vol. 44, pp. 265-69, 1912. 



f Private information from the Hon. Ct. M. Thomson. 



