莱鲍迪苷A甜味剂在功能性酸奶中的应用研究

Application of rebaudioside A sweetener in sugar-free yoghurt

用莱鲍迪苷A替代蔗糖后,酸奶的色泽较对照组更白,凝乳状态基本没有发生变化,酸奶凝乳好,表面光滑。但酸奶的持水性能明显下降,在酸奶的表面均出现乳清析出。随着莱鲍迪苷A替代量的增加,酸奶的酸味评分先增加后下降,但普遍低于对照组。同时,酸奶的甜味、苦味和柔和感评分与对照组相比都有所下降。相反地,酸奶的乳香味评分有所上升。当莱鲍迪苷A替代蔗糖后酸奶的各项感官品质普遍下降,综合分析可知莱鲍迪苷A的最优替代量为50%。但是,当替代量为50%时,酸奶的乳清析出比较明显,而且酸甜不和谐,口感不够柔和,如果要用莱鲍迪苷A制作无糖酸奶还需要对其进行复配。在单因素试验的基础上以莱鲍迪苷A、赤藓糖醇、低聚异麦芽糖用量为自变量,酸奶感官、pH、硬度、稠度、黏附性、持水力为响应值,对酸奶复合甜味剂配方进行响应面优化。优化后无糖酸奶的最优配方为:复原乳100mL,莱鲍迪苷A 0.02 g,赤藓糖醇1.809 g,低聚异麦芽糖2.908 g,稳定剂0.1 g,CaCl20.02 g,接种量4 mL。用该配方制作的无糖酸奶色泽洁白,结构均匀细腻,酸甜适宜,口感柔和。

The study provides a theoretical basis for deeply study and research on rebaudioside A sweetener.The rebaudioside A can be used in the diabetic＇ s diet and people with phenylketonuria as a natural and non-caloriesweetener.The sweetener played an important role in yoghurt making.In this study,we investigated the effects of rebaudioside A,erythritol and Isomalto-oligosaccharide combinations on sensory score,hardness,consistency,viscosity,pH and water-holding capacity of sugar-free yoghurt.A central composite rotatable design （CCRD） was adopted to obtain data for the correlative statistical models.Through the response surface analysis,the optimum formulation conditions of sweetener combinations based onsensory properties,texture,pH and water-holding capacitywere：rebaudioside A 0.02％,erythritol 1.809％ and IMO 2.908％.In the above condition,the yoghurt color was milky white,perfect sugar to acid ratio and better texture.