VITAMIN DETERMINATION: Rapid Estimation of Vitamin A Using a Surface Active Agent

Abstract

An improved procedure employs a single-step extraction for determining naturally occurring vitamin A in chicken livers, synthetic vitamin A in fortified powdered formulas for infants, and stabilized vitamin A in animal feed supplements. Stabilized vitamin A is determined in the presence of , '-diphenyl-p-phenylenediamine by a simple modification of the procedure. The vitamin A is solubilized in the test material with the surfactant and extracted with a mixed solvent. Twenty-five minutes are required for one extraction and several may be run simultaneously. The procedure gives good recovery replication, and results comparable to those obtained by saponification. THE DETERMINATION OF VITAMIN A in food products usually requires saponification (2), which in the case of milk may take as long as 3 hours (3), as well as numerous

Evaluation of Carotenoid Concentration in Chicken Tissues

“…The chemical procedures used to determine total carotenoids in each of the various tissues were described, respectively, in the following references: blood (Kimble, 1939); skin (Potter et al, 1956); liver (Gade et al, 1956;and Kaser et al, 1943). Liver carotenoids and liver vitamin A were determined by combining the procedures given in the latter two references.…”

Utilization of Vitamin A Activity from Alfalfa or Fish Oil by Chicks Receiving Diets with and without Diphenyl-P-Phenylenediamine (DPPD)

“…The composite liver samples from each sex were blended in a Waring Blender and a 2 gram aliquot was used for vitamin A analysis. Vitamin A in the livers was determined by the method of Gade and Kadlec (1956). The blue color which was developed with the Carr Price Reagent was read on the Evelyn Colorimeter.…”

Food

“…Values in the tables are recorded only for the difference range 0.04 to 0.09, as differences outside these limits are rarely encountered with E values of 0.4 to 0.6. An improved procedure for vitamin A in chicken livers and synthetic vitamin A in fortified pow'dered formulas for infants employs a singlestep extraction (91).…”