6种市售西藏酥油理化指标及物理特性分析  

PHYSICOCHEMICAL INDEXES AND PHYSICAL CHARACTERISTICS OF SIX KINDS OF MARKET TIBET BUTTERS

作　　者：李婕妤 马传国[1,2] 王英丹 季敏 李胜 LI Jieyu;MA Chuanguo;WANG Yingdan;JI Min;LI Sheng(School of Food Science and Technology,Henan University of Technology,Zhengzhou 450001,China;Grain and Oil Food Engineering Technology Research Center,State Administration of Grain,Zhengzhou 450001,China;Palm Oil Research and Technical Service Institute of MPOB(Shanghai),Shanghai 201108,China)

机构地区：[1]河南工业大学粮油食品学院,河南郑州450001 [2]国家粮食局粮油食品工程技术研究中心,河南郑州450001 [3]大马棕榈油技术研发(上海)有限公司,上海201108

出　　处：《河南工业大学学报（自然科学版）》2018年第3期38-46,57,共10页Journal of Henan University of Technology：Natural Science Edition

基　　金：马来西亚棕榈油总署(MPOB)合作项目(PORTSIM045-2016)

摘　　要：西藏酥油是从牦牛牛奶中提取的油脂产品,在西藏地区作为藏民主要的食物来源,同时还是宗教活动中制作酥油花和酥油灯必不可少的原料,其制作工艺复杂繁琐且不易储存。以西藏地区的6种市售西藏酥油产品为研究对象,测定了其主要成分及理化指标,使用气相色谱仪、脉冲核磁共振仪、流变仪、差示扫描量热仪和X-射线衍射仪分别测定了酥油的脂肪酸组成、固体脂肪含量、流变学性质、热力学性质以及晶型。结果表明,西藏酥油产品主要含有棕榈酸(28%~34%)、油酸(21%~37%)和硬脂酸(9%~19%),高含量的饱和脂肪酸是西藏酥油呈现固体状态的原因,且它们都含有少量的反式脂肪酸。6种酥油的固体脂肪含量和热力学性质表明其熔化温度的范围较大,因此具有很好的可塑性,可用于制作酥油花。酥油的流变学性质表明其弹性模量(G′)均大于黏性模量(G″),呈现类固体性质,均属于剪切变稀流体。XRD结果表明,6种酥油产品均以β'晶型为主,呈现出柔软的质地,因此,西藏酥油具有起酥、搅打、可塑性等功能,可以作为食品和酥油花的原料。Tibet butter which is extracted from yak milk grease products,is not only the major food source in the Tibet region,but also is an essential raw material for making butter sculpture and butter lamps in religious activities.The production process of Tibet butter is complicated and the butter products are not easy to store.Therefore,the main components,physical and chemical indexes of six kinds of commercial Tibet butters products were determined in the present study.The fatty acid compositions,solid fat contents,rheological properties,thermodynamic properties and crystal type were analyzed using GC,NMR,rheological,DSC and XRD methods,respectively.The results showed that the mainly fatty acid compositions of Tibet butters were palmitic acid(28%-34%),oleic acid(21%-37%)and stearic acid(9%-19%).The higher content of saturated fatty acids was the reason that Tibet butter existed in solid status.Moreover,the six kinds of Tibet butters all contained a small amount of trans-oleic acid.The results of solid fat contents and thermodynamic properties showed that the melting temperature ranges of six Tibet butter products were large,indicating their strong plasticity.The analysis of rheological properties indicated that the elastic modulus(G′)of six kinds of Tibet butter products was greater than the viscous modulus(G″),implying they all belonged to the shear thinning fluid and showed solid-like properties.The results of XRD showed that all the 6 kinds of products had soft texture and mainly containedβ'-crystal.In conclusion,the Tibet butter has the function of crisp,beating and plasticity,which can be used as the raw material of food and butter sculpture.

关 键 词：西藏酥油 脂肪酸组成 热力学性质 流变学行为 晶型 

分 类 号：TS225[轻工技术与工程—粮食、油脂及植物蛋白工程]