Journal of Food Science · 1994 · 64 citations · 13 references
AgricultureBiochemistryFood ScienceFood ChemistryFood ProcessingProtein BiochemistryFruit BiochemistryFruit PhysiologyFruit QualityJuice ProcessingPectin ChemistryProteins In FoodsParamagnetic SpeciesPectin BehaviorPectin CharacterizationPectin Content AnalysisPectin Hydrolysis ProductsPectin PrecipitationPectin SolubilityPectin Solubilization
ABSTRACT The cloud pectin content of two commercial orange juice concentrates was 4.7 and 4.3%. The cloud pectin was solubilized to varying degrees in 6% citric acid. pH 2.5; in 10M urea‐6% citric acid, pH 2.5; by hydrolysis of cloud protein with protease; and in sodium oxalate; pH 4.5. Much of the urea‐solubilized pectin reprecipitated upon dialysis. The binding of orange cloud to amino paramagnetic latex particles demonstrated a clear association of cloud pectin with cloud protein. Simulation of orange juice processing conditions indicated that some of the cloud pectin arises from the pulp during processing. About 60% of the cloud pectin is soluble pectin that has become associated with cloud protein, 25–30% is calcium pectate and 15% is protopectin.
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Colorimetric Determination of Pectic Substances
E. A. McComb, R. M. McCready · Analytical Chemistry · 1952 · 330 citations