摘要:

Acetic acid has been identified as the only volatile acid produced in spoiling cod muscle press juice. Lactic acid present and that formed from some unknown precursor is oxidized to acetic acid and carbon dioxide. The significance of these results is discussed.

ISSN:0706-652X    

DOI:10.1139/f40-020

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Cod muscle press juice during storage shows a decrease and later an increase in buffering capacity, both due to bacterial action. Reduction of trimethylamine oxide causes the decrease, and oxidation of lactic acid to acetic acid slightly lessens the effect. The increase is possibly entirely due to hydrolysis of protein by bacteria. Since the decrease occurs during the onset of spoilage, the buffering capacity gives useful data as to the state of preservation.

ISSN:0706-652X    

DOI:10.1139/f40-021

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Normal human urine contains small amounts of trimethylamine oxide but no appreciable trimethylamine. Trimethylamine when administered orally appears mainly as trimethylamine oxide in the urine; trimethylamine oxide similarly administered is excreted unchanged, thus proving the existence in man of a system capable of oxidizing trimethylamine.

ISSN:0706-652X    

DOI:10.1139/f40-022

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

An examination of fish digestive organs showed that only the pyloric caeca and intestine showed a sufficiently high yield and a sufficiently high activity to make their commercial use feasible. The intestine had approximately one-quarter the activity of the caeca. Mackerel caeca showed the highest activity and yield of any organ in four species of fish examined. No activating effect parallel to that of mammalian enterokinase on trypsinogen was demonstrated. By comparing the hydrolysis products of casein by pyloric caeca, intestinal mucosa, and hog pancreas, evidence was adduced showing that the enzymic constituents of these preparations are similar.

ISSN:0706-652X    

DOI:10.1139/f40-023

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

American mergansers and belted kingfishers that eat large parr, particularly during the low water of dry summers, fulfilled the prediction (based upon statistics) that the periodic scarcity of Atlantic salmon is due to a factor operating on the salmon when near the smolt stage. One year's bird control more than doubled the number of descending smolts and correspondingly increased the sea catch of salmon related to the experimental river, as demonstrated by the occurrence of fish marked as smolts in the river. Bird control may thus remedy periodical scarcity. This serves to explain the favourable influence on numbers of fish that man's presence has been observed to have.

ISSN:0706-652X    

DOI:10.1139/f40-024

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

In Bideford "river", an arm of Malpeque bay, soon after ice forms a thin layer of water of very low salinity develops with a minimum temperature above the freezing point of the salter water below. Convectional mixing of surface and bottom waters is largely prevented. The temperature of the latter seldom approaches its freezing point closely and rises during the winter to approach that of the water in contact with the ice.

ISSN:0706-652X    

DOI:10.1139/f40-025

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Ice containing sodium nitrite plus sodium acid phosphate inhibits bacterial spoilage of dressed chum salmon to approximately the same extent as sodium nitrite ice alone. Intensity of red colour in the cooked muscle of this fish is normally intensified by sodium nitrite.

ISSN:0706-652X    

DOI:10.1139/f40-026

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Eb.typhosaandEs.colisurvive on salt fish agar and in salt fish broth at 5 to 6 °C. for periods of three months and more. On salt fish itself survival is reduced, particularly for the former organism. Survival is favoured by low storage temperatures and heavy contamination.

ISSN:0706-652X    

DOI:10.1139/f40-027

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

Below 5 °C. oysters do not change in fatness, as judged by the ratio, dry weight to space between the valves. Between 5 and 15° they get thin. Between 15 and 20° they fatten. Above 20° they may fatten slightly but spawning makes them thin. When the salinity drops below 20‰ no fattening takes place even at temperatures between 15 and 20°.

ISSN:0706-652X    

DOI:10.1139/f40-028

出版商:NRC Research Press    

年代:1941

数据来源: NRC

摘要:

This trout in Moser river, Nova Scotia, descends to the sea in April and May, with risin, temperature. Falling temperature lessens or stops descent, causing some to return upstream. The smallest showed straying in 1940 to other streams several miles distant and smaller percentage return to river than for other sizes. Return was related to freshets in the main river, rather than in tributary of origin. Homing to latter was definite, but only partial, and apparently lessened by winter sojourn elsewhere. Period of absence in sea ranged from 42 to 84 days.

ISSN:0706-652X    

DOI:10.1139/f40-029

出版商:NRC Research Press    

年代:1941

数据来源: NRC