Colorimetric Method for Determining Dialdehyde Content of Periodate-Oxidized Starch

Oxidized Starch as a Hardening Agent in the Gelatin‐Immobilization of Living Yeast Cells

“…The dialdehyde content of periodate-oxidized starch was measured by the method of Wise and Mehltretter [4]. Sugar Concentration in cane molasses was measured by the phenolsulfate method [ S ] .…”

The Determination of Small Concentrations of Carbonyl Groups in Starch by the Cyanohydrin Method

“…Sloan et al (16) showed, by analyzing the oximes prepared from their periodate starches, that their periodate oxidations were practically quantitative in the concentration range between 1 C=0 per 5 A.G.U. 's and 1 C=0 per 50 A.G.U.'s.…”

“…The method is both accurate and easily handled, and is applicable to carbonyl concentrations in starch of the order of 1 carbonyl per 50 anhydroglucose units or lower. THE DETERMINATION in starch of total carbonyl (= aldehyde + ketone) or of aldehyde and ketone groups separately may be based on one of a number of principles: determinations of reducing power, such as ferricyanide number (6), hypoiodite oxidation (2, IS); alkali consumption (4), colorimetry (16), borohydride reduction (12), formation of bisulfite addition compound (2, 14), chlorous acid oxidation (2, 5, 10), or oximation reaction (S). The last named method was later admitted (2) not to be applicable to small carbonyl concentrations, involving as it does an acidimetric titration in a highly buffered medium; it gave satisfactory results, however, with hypochlorous acid oxystarches (9).…”

Food

“…for determining the degree of oxidation in a starch. Starches oxidized with hypochlorite contained carboxyl groups that liave a strong affinity for methylene blue (74)• The carbonyl group content of oenodate-oxidized starch has been mea.-.ured by conversion of the oxystarch ro the p-nitrophenylhydrazone, which was determined speetrophotomctrically (370).…”