作　　者： ; ; ; ;

机构地区： 华南理工大学轻工与食品学院轻化工研究所

出　　处： 《华南理工大学学报（自然科学版）》 2006年第8期79-83,共5页

摘　　要： 研究了木薯和马铃薯淀粉经有效氯含量小于1%(质量分数,下同)的次氯酸钠氧化后的理化性质及反应机理.发现氧化淀粉的羰基和羧基含量随次氯酸钠用量的增加而增加,且马铃薯氧化淀粉的羰基和羧基含量均比木薯氧化淀粉高.Brabender粘度仪分析表明,当有效氯含量小于或等于0.3%时,氧化淀粉的峰值粘度和最终粘度都较原淀粉高.红外光谱分析表明:有效氯含量为0.9%时,木薯和马铃薯淀粉在1733 cm-1和1 714 cm-1处产生了吸收峰;而当有效氯含量为0.1%时淀粉在此处的吸收峰有所减弱或消失,在1 150 cm-1附近处的吸收峰有所加强.由此推测淀粉轻度氧化过程中发生了交联反应,此反应为淀粉氧化后的醛基与邻近淀粉分子中的羟基发生交联. Cassava and potato starches were oxidized by sodium hypochlorite with an active chlorine content of less than 1% （mass fraction, below the same）. The oxidization mechanism and the physicochemical properties of the oxidized starches were then studied, revealing that both the carbonyl content and the carboxyl content of the oxidized potato starch are higher than those of the oxidized cassava starch, although the carboxyl and carbonyl contents of the two oxidized starches all increase with the dosage of sodium hypochlorite. As measured by Brabender Viscography, the oxidation at low active chlorine content （ ≤0.3% ） results in higher peak and final viscosities of the oxiare observed in the FTIR spectra of the cassava and photo starches oxidized at an active chlorine content of 0.9%, which weaken or disappear when the oxidation is carried out at an active chlorine content of 0.1%. However, the absorption at 1150 cm^- 1 is strengthened. It is thus concluded that a cross linking reaction takes place between the hemiacetal hydroxyl groups of the oxidized starch and the hydroxyl groups of the adjacent starch during the low-level oxidation process.

关 键 词： 淀粉 氧化 次氯酸钠 交联 机理

领　　域： [生物学] [轻工技术与工程] [轻工技术与工程]