摘要:

An extract suitable for the quantitative determination of nitrite, nitrate, and chloride in cured meat was prepared by freezing and thawing the sample, followed by extraction with hot water. The sulphanilic acid-α-naphthylamine hydrochloride method, applied to the photoelectric colorimeter, was suitable for the determination of nitrite in meat extract and curing pickle. A number of factors that affect this reaction were investigated. The nitrate content of cured meat and curing pickle was determined by the phenoldisulphonic acid method, slightly modified and applied to the photoelectric colorimeter. The chloride content of meat extract was determined, either by direct titration with potassium chromate as indicator, or by Volhard's procedure, after the removal of protein by ignition or wet oxidation. The latter method should be used if accuracy within 5% is desired. Direct titration was satisfactory for the determination of chloride in curing pickle.The precision of the above methods is illustrated by the following average deviations of individual determinations from their means, as computed from 25 or more duplicate determinations, and expressed as a percentage of the amount present, for meat and pickle respectively: chloride, ±0.20% and ±0.02%; nitrate ±0.70% and ±0.30%; nitrite, ±1.7% and ±0.1%.

ISSN:1923-4287    

DOI:10.1139/cjr39d-015

出版商:NRC Research Press    

年代:1939

数据来源: NRC

摘要:

A mathematical treatment of the process of synthesis of protein material in the pancreas, and its secretion in response to secretin administration, has been developed. It was based on assumptions inferred from experimental data and from analogy with a suggested mechanism for the submaxillary gland, published previously. It leads to expressions that quantitatively describe the protein output in samples of pancreatic juice obtained under widely varied experimental conditions. Inferences concerning the fundamental character of certain glandular mechanisms may be drawn from the treatment. In addition it permits provisional calculation of various factors not directly observable in critical experiments, and suggests further problems in connection with the secretory processes.

ISSN:1923-4287    

DOI:10.1139/cjr39d-016

出版商:NRC Research Press    

年代:1939

数据来源: NRC