中国农业科学 ›› 2016, Vol. 49 ›› Issue (19): 3831-3844.doi: 10.3864/j.issn.0578-1752.2016.19.014

• 贮藏·保鲜·加工 • 上一篇    下一篇

发酵对苹果渣多糖加工特性的影响

贾 丰,郭玉蓉,刘 冬,杨 曦,邓 红,孟永宏   

  1. 陕西师范大学食品工程与营养科学学院,西安 710119
  • 收稿日期:2016-03-22 出版日期:2016-10-01 发布日期:2016-10-01
  • 通讯作者: 郭玉蓉,E-mail:yurongguo730@163.com
  • 作者简介:贾丰,E-mail:feng_juslin@163.com
  • 基金资助:
    农业部现代苹果产业技术体系建设专项(CARS-28)

Effect of Fermentation on the Polysaccharides Processing Characteristics in Apple Pomace

JIA Feng, GUO Yu-rong, LIU Dong, YANG Xi, DENG Hong, MENG Yong-hong   

  1. College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi’an 710119
  • Received:2016-03-22 Online:2016-10-01 Published:2016-10-01

摘要: 【目的】中国苹果年均产量占世界总产量的50%以上,其中约有20%用于工业化深加工。因此,每年将产生数以万吨的苹果渣,这些苹果渣一般作为廉价饲料出售或作为废料丢弃,造成资源极大浪费。比较苹果渣发酵前后多糖的物理特性、流变特性、黏均分子量及基本结构等加工特性,为苹果渣多糖的开发利用提供新的思路和依据。【方法】以苹果原渣多糖(apple pomace polysaccharides,AP)、苹果酒渣多糖(wine fermented apple pomace polysaccharides,WFP)、苹果醋渣多糖(vinegar fermented apple pomace polysaccharides,VFP)为原料,通过对苹果渣多糖提取率、溶解性、乳化性及其稳定性、起泡性及其稳定性、吸湿性与保湿性等物理指标进行全面测定、利用流变仪测定多糖溶液流变学特性、利用台式扫描电镜(DSEM)对多糖微观结构进行观察,同时利用乌氏粘度计对多糖进行黏均分子量测定,从而对加工特性进行全方位的对比研究。【结果】AP提取率为5.68%,发酵苹果渣多糖提取率为6%—7%,与AP差异显著(P<0.05)。VFP、WFP在水中溶解度分别为0.1405 g·mL-10.0771 g·mL-1,均与AP(0.0283 g·mL-1)存在显著差异(P<0.05)。与AP相比,发酵苹果渣多糖起泡稳定性有所增加,吸湿性、保湿性明显升高(P<0.05),但吸油性、乳化性及乳化稳定性均显著降低(P<0.05)。此外,在流变学方面,AP、VFP、WFP均为典型的非牛顿流体,其表观黏度存在明显的浓度依赖特征;WFP、VFP 具有良好的温度抗逆性。黏均分子量和微观结构分析表明,AP、WFP、VFP黏均分子量在15—130 kDa,黏均分子量的大小顺序依次为:AP>WFP>VFP。台式扫描电镜微观结构图像显示,AP主要由条带、棒状、片状组成,结构间相互交联,形成网状结构;WFP主要由齿状、棒状和片状组成,有一定交联性,但交联程度相对较低;VFP主要由较大的片状组成,弯曲折叠在一起,交联程度相对最低。【结论】发酵苹果渣多糖在物理特性、流变学特性、基本结构、黏均分子量等方面均有所提升,苹果酒渣多糖、醋渣多糖加工特性优于原渣多糖。

关键词: 苹果渣多糖, 发酵, 物性, 流变性, 结构, 加工特性

Abstract: 【Objective】The output of apple in China accounts for over 50% of the world annually. Among those apples, there are about 20% of apple fruits are used as raw materials to produce deep-processed products. As a result, apple pomace of thousands of tons are produced each year, which has caused the tremendous waste of apple recourse because these pomace are generally sold as a cheap fertilizer or are discarded directly as junks. The difference of physical and rheological property, viscosity-average molecular weight, and basic structure of polysaccharides between raw pomace and fermented apple pomace was studied in order to provide innovative thoughts and a theoretical basis for the exploitation of apple polysaccharides.【Method】Apple pomace (AP), wine fermented apple pomace polysaccharides (WFP), vinegar fermented apple pomace polysaccharides (VFP) were used as experimental materials, the paper investigated overall the processing properties of polysaccharides in fermented apple pomace through comparing with the extract ratio, solubility, hygroscopicity, moisture retention, and emulsifiability, foaming capacity and stability among AP, WFP and VFP. Besides, the rheological properties, microstructure, viscosity-average molecular weight were determined by using rheometer, desktop scanning electron microscope (DSEM), ubbelohde viscometer, respectively.【Result】The extraction ratio of AP was 5.68%, while that of polysaccharide in fermented apple pomace was 6%-7%, both of which had a significant difference (P<0.05). The solubility of VFP and WFP were, respectively, 0.1405 g·mL-1 and 0.0771 g·mL-1, and significantly higher (P<0.05) than AP (0.0283 g·mL-1). Compared to AP, the stability of foaming, hygroscopicity, moistureretention of polysaccharides, fermented apple pomace were significantly increased (P<0.05), while oil absorption, emulsifiability and its stability obviously decreased (P<0.05). According to analysis on rheological property, AP, WFP, VFP could be attributed to typical non-Newtonian fluid, and the apparent viscosity showed obvious dependent-characteristic of concentration. Besides, VFP and WFP had great resistance against temperature change. The findings of analysis of viscosity-average molecular weight and DESM indicated that the viscosity-average molecular weight of AP, WFP, VFP all distributed in the range of 15-130 kDa, and AP>WFP>VFP. Additionally, the microstructure analysis showed that AP consisted of band, bar and flake, twining with each other and forming firm network. WFP contained dentation, bar and flake, so its cross-linking was comparatively lower. But VFP mainly consisted of flake, overlapping with one another, and cross-linking was the lowest.【Conclusion】WFP, VFP were greatly improved in physicaland rheological properties, microstructure and viscosity-average molecular weight, indicating the processing property of polysaccharides in fermented apple pomace was superior to AP.

Key words: apple pomace polysaccharide, fermentation, properties, rheology, structure, processing characteristics