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标题：Influence of pH and heat treatment on β-lactolobulin-oleic acid complex
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作者：Ana-Maria SIMION (CIUCIU) ; Iuliana APRODU ; Petru ALEXE 等
期刊名称：Annals of the University Dunarea de Jos of Galati. Fascicle VI : Food Technology
印刷版ISSN：1843-5157
电子版ISSN：2068-259X
出版年度：2015
卷号：39
期号：2
页码：64-76
出版社：Galati University Press
摘要：One of the major concerns of food technologists is to produce healthier productswith specific functionalities. The potential use of β-lactoglobulin as a supplementfor new functional products is encouraging due to its nutritional and functionalcharacteristics. The aim of this work was to obtain β-lactoglobulin-oleic acidcomplexes at different pH values (5.0, 6.0, and 7.0) and to test their stability atdifferent temperatures (25-85°C) such as to allow identifying their potential use ina variety of food products. The complexes were characterized through differentfluorescence spectroscopy based techniques: phase diagram, intrinsic and extrinsicfluorescence, along with fluorescence quenching experiments. Results showed thepresence of more than two structurally distinct species with intermediates asinduced by thermal treatment. The heat treatment at temperatures higher than70°C caused an increase in both intrinsic and ANS fluorescence intensity.Acrylamide quenching showed no significant differences between the values ofStern-Volmer constants as function of temperature for pH 5.0, suggesting that nosignificant changes occurred in the Trp microenvironments. Quenchingexperiments with KI lead to decreases in Stern-Volmer constants in thetemperature range 25-70°C, suggesting protein folding, whereas at highertemperatures a small increase was observed suggesting unfolding and an increasedaccessibility of the fluorophore to the quencher for all pH values.
关键词：β-lactoglobulin; oleic acid; complex; pH