Microstructural and dynamic oscillatory aspects of yogurt as influenced by hydrolysed guar gum
Microstructural and dynamic oscillatory aspects of yogurt as influenced by hydrolysed guar gum
复制标题
DOI：
10.1111/ijfs.13500
复制
发表时间：
2017-10-01
影响因子：
3.3
通讯作者：
Ismail, Amir
中科院分区：
文献类型：
--
作者：
Hussain, Majid;Bakalis, Serafim;Ismail, Amir
本研究的目的是探讨低浓度和高浓度的瓜尔豆胶粗品、精制和水解胶在4℃下贮藏21d对酸奶凝胶结构稳定性的影响。用Bohlin流变仪(英国马尔文流变仪)和冷冻扫描电子显微镜(Cryo-SEM)观察了酸奶的流变性和微观结构。25℃下酸奶的粘弹性表现出较弱的凝胶结构特性(G“>；G‘)。冷冻-扫描电子显微镜用于微观结构图像处理。低(0.3%)和高(1%)浓度的瓜尔豆胶的酸性和酶解态导致酸奶凝胶具有细链的微结构，而粗瓜尔胶、纯瓜尔胶和碱性水解瓜尔胶的凝胶表现出不同的耗竭絮凝行为，即使在较低浓度的粗瓜尔胶(0.1%)作为一层薄薄的相分离物质时也可以观察到。综上所述，瓜尔胶的水解态改善了更好的结构和流变性。
The objective of the current study was to explore the influence of crude, purified and hydrolysed guar gum at low and high concentrations on gel structure stability of yogurts at 4 degrees C throughout 21days of storage. The rheology and microstructure of yogurts had been perceived by Bohlin rheometer (Malvern Instrument, UK) and cryo-scanning electron microscopy (Cryo-SEM), respectively. The viscoelastic behaviour of yogurts characterised at 25 degrees C exhibited weak gel structural properties (G">G'). Cryo-SEM had been used for microstructural image processing. The acidic and enzyme hydrolysed guar gum at low (0.3%) and high (1%) concentrations led to yogurt gels with fine-stranded microstructure, while gelation with crude, purified and basic hydrolysed guar gum demonstrated diverse behaviour of depletion flocculation, visually observed even at low concentrations of crude guar gum (0.1%) as a thin layer of phase-separated material. Conclusively, guar gum in its hydrolytic form enhances better structural and rheological properties.