| 摘要: |
| 【目的】研究葛根粉初始质量浓度和混合物中牛奶体积分数对葛根粉-牛奶混合物相行为、稳定性及相关性质的影响，为该功能性复合饮料的开发提供基础数据。【方法】利用天然葛根粉与传统饮料牛奶通过共混法配制复合饮料，并通过浊度仪、Zeta电位仪、粒径分析仪、差示扫描量热仪、正置荧光显微镜等多种仪器对混合体系予以表征,分析不同初始质量浓度葛根粉和不同体积分数牛奶混配的葛根粉 牛奶混合物的稳定性及相行为的变化。【结果】观察发现，当葛根粉初始质量浓度为1 g/L时，葛根粉-牛奶混合物未出现明显的相分离，而当葛根粉初始质量浓度增加到25 g/L时，混合物出现明显分层现象。葛根粉-牛奶共混体系表现出稳定、亚稳定、不稳定3种状态。初始质量浓度为1 g/L的葛根粉与任意体积分数的牛奶配制的葛根粉-牛奶混合物均表现稳定，无聚集体产生。当葛根粉初始质量浓度高于5 g/L且牛奶体积分数低于40%时，二者混合物会出现聚集现象，此时要得到稳定体系，则需将其中的牛奶体积分数增加到40%以上。混合物的浊度主要与牛奶体积分数有关。混合物Zeta电位的绝对值随牛奶体积分数的增大而增大。随葛根粉初始质量浓度的增加，混合物的粒径分布变宽且大粒径粒子的比例增加。向牛奶中添加葛根粉，可以使混合物的热学性能发生改变。正置荧光显微镜观测表明，随着牛奶体积分数增大，混合体系微观结构由不均匀逐渐向均匀转变。【结论】葛根粉-牛奶混合物的稳定性与葛根粉初始质量浓度及牛奶体积分数有关，随着葛根粉初始质量浓度的降低(即从25 g/L降至1 g/L)或混合物中牛奶体积分数的增加(即从0%增至100%)，共混体系的稳定性增加。 |
| 关键词: 葛根粉 牛奶 复合饮料 |
| DOI： |
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| 基金项目:国家自然科学基金项目（51263009） |
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| Phase behavior and stability of pueraria-milk blend system |
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KANG Huiting,AN Kai,GUAN Lianxiong,et al
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| Abstract: |
| 【Objective】The effects of initial mass concentration of pueraria and volume fraction of milk on phase behavior,stability and related properties of the pueraria milk mixture were studied to provide basic data for the development of this functional compound beverage.【Method】In this work,a compound beverage was prepared by blending natural pueraria with milk (a traditional beverage).The blend system was characterized by turbidimeter,particle size analyzer,Zeta potentiometer,differential scanning calorimeter,and vertical fluorescence microscope.The stability and phase behavior of pueraria-milk mixture under different initial mass concentrations of pueraria and different volume fractions of milk were studied.【Result】When the initial mass concentration of pueraria was 1 g/L,there was no phase separation in pueraria-milk mixture.When it was increased to 25 g/L,there was phase separation in the mixture.Pueraria-milk blend system showed three states of stable,metastable and unstable.The pueraria milk mixture prepared from pueraria with initial mass concentration of 1 g/L and any volume fraction of milk was relatively stable and no aggregation occurred.When the initial mass concentration of pueraria was higher than 5 g/L and the volume fraction of milk was lower than 40%,the blend system began to aggregate.To obtain a stable system,the volume fraction of milk should be increased by up to 40% under this circumstance.The turbidity of the mixture was mainly related to volume fraction of milk.The absolute value of Zeta potential of the mixture increased with the increase of volume fraction of milk.As the initial mass concentration of pueraria increased,the particle size distribution of the mixture became wider and the proportion of large-sized particles increased.The thermal properties of the mixture could be altered by adding pueraria to milk.Besides,the upright fluorescence microscop showed that the microstructures of the miture were changed from non uniform to uniform with the variation of milk volume fraction.【Conclusion】The stability of pueraria-milk mixture was related to both initial mass concentration of pueraria and volume fraction of milk.With the decrease of initial mass concentration of pueraria (i.e. from 25 g/L to 1 g/L) or the increase of volume fraction of milk (i.e.,from 0% to 100%),the stability increased. |
| Key words: pueraria milk compound beverage |
