HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Johnston, J. H. Search for Related Content PubMed Articles by Johnston, J. H.

The Temperature of Solution of Butter Fat in Various Reagents

The Laboratory, Effingham House, London

ABSTRACT

The temperature at which a fat or an oil forms a homogeneous mixture with certain solvents forms one of its physical constants. The constant varies with the solvent used,and with the conditions under which the determination is made. Most use has been made of the determination in the case of butter fat, since it forms a convenient method of detecting the substitution of margarine for butter. The reagent usually used has been glacial acetic acid, and in this case the determination has been known as the Valenta test, and the temperature observed as the Valenta number. The determination is made by heating equal volumes of the dry filtered fat and glacial acetic acid (usually 3 cc.) in a test tube until clear, stirring with a thermometer meanwhile. The mixture is then allowed to cool, continuing the stirring, and the temperature is noted at which turbidity first appears. In the case of butter fat, this is about 35°C.