Spreading of Monoglycerides onto -Casein Adsorbed Film. Structural and Dilatational Characteristics

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• 作者：Juan M. Rodrí ; guez Patino ; Marta Cejudo Ferná ; ndez ; M. Rosario Rodrí ; guez Niñ ; o ; and Cecilio Carrera Sá ; nchez
• 刊名：Journal of Agricultural and Food Chemistry
• 出版年：2006
• 出版时间：May 17, 2006
• 年：2006
• 卷：54
• 期：10
• 页码：3723 - 3732
• 全文大小：282K
• 年卷期：v.54,no.10(May 17, 2006)
• ISSN：1520-5118

文摘

The effect of monoglycerides (monopalmitin and monoolein) on the structural, topographical, anddilatational characteristics of ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein adsorbed film at the air-water interface has been analyzedby means of surface pressure (ages/gifchars/pi.gif" BORDER=0 >)-area (A) isotherms, Brewster angle microscopy (BAM), and surfacedilatational rheology. The static and dynamic characteristics of the mixed films depend on the interfacialcomposition and the surface pressure. At surface pressures lower than that for the ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein collapse(at the equilibrium surface pressure of the protein, ages/gifchars/pi.gif" BORDER=0 >_e^{ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein}) a mixed film of ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein andmonoglyceride may exist. At higher surface pressures the collapsed ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein is partially displacedfrom the interface by monoglycerides. However, ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein displacement by monoglycerides is notquantitative at the monoglyceride concentrations studied in this work. The protein displacement by amonoglyceride is higher for monopalmitin than for monoolein and for spread than for adsorbed films.The viscoelastic characteristics of the mixed films were dominated by the presence of ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein inthe mixture. Even at the higher surface pressures (at ages/gifchars/pi.gif" BORDER=0 > > ages/gifchars/pi.gif" BORDER=0 >_e^{ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein}) the small amounts of ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-caseincollapsed residues at the interface have a significant effect on the surface dilatational properties ofthe mixed films. The structural, topographical, and viscoelastic characteristics of the mixed filmscorroborate the fact that protein displacement for monoglycerides is higher for spread than for adsorbedmixed films.Keywords: Milk protein; ages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-casein; monoglyceride; monopalmitin; monoolein; air-water interface;adsorbed monolayer; spread monolayer; mixed monolayer; surface rheology