不同种类动物肉结构、质构及营养特性的对比研究

Comparison Study of Structure,Texture and Nutrition of Animal Meet

以猪里脊、鸡胸肉和4个部位的牛肉(牛里脊、牛楠、牛小黄瓜条、牛肩)为研究对象,表征肉的多级结构、质构特性、水分分布、营养组成及体外模拟消化特性,解析肉的多级结构与质构及消化的内在关系,旨在为建立植物肉对标动物肉的品质评价体系提供理论基础。结果表明,肉是典型的多级结构,肌纤维、肌外膜、肌束膜以及肌内膜分层排列在复杂的网络结构中。不同动物肉肌纤维束的形态、粗细、排列紧密度差异较大,鸡纤维束的形态种类最丰富,猪里脊的纤维束直径最大(75.21μm),其次是牛腩(57.09μm)、牛小黄瓜条(54.41μm)和鸡胸肉(52.78μm),牛里脊的纤维束直径最小(33.58μm),牛小黄瓜条、牛肩、牛腩的肌纤维束排列较为致密,鸡胸肉、猪里脊和牛里脊排列较为疏松。核磁成像结果表明,6种动物肉均含有3种形式的水分,包括蛋白结合水、固定水(肌原纤维内水)、自由水(肌原纤维外水)。鸡胸肉和猪里脊的水分分布均一,固定水含量高。4个部位的牛肉水分分布不均匀,且牛肉内部的脂肪较多。动物肉不同形式水分含量以及分布影响其质构特性。肉的微观结构和质构及消化性具有一定相关性,纤维束排列紧密的肉硬度和咀嚼度较大,消化率较低。基于动物肉结构、质构及营养特性解析的结果,可为植物肉产品品质评价标准的建立提供科学依据。

Selecting pork loin,chicken breast and four different parts of beef(tenderloin,flank,eyeround and shoulder) as materials,the multi-level structural properties,texture characteristics,water distribution,nutrient composition and in vitro simulated digestion characteristics of meat were characterized,and the internal relationship between the multi-level structure,texture and digestion of meat was analyzed,aiming to provide a theoretical basis for establishing a quality evaluation system of plant-based meat analogues.The results show that meats had typically multi-hierarchical structures with muscle fibers,epicardium,sarcolemma and endocardium layered in a complex network structure at different scales.The tightness and thickness of meat fiber fascicle showed differences for these six types of meats.The morphological types of chicken fiber were the richest.The fiber bundle diameter of pork was the largest(75.21 μm),followed by flank(57.09 μm),eyeround(54.41 μm) and chicken(52.78 μm).The fiber bundle diameter of tenderloin was the smallest(33.58 μm).The muscle fibers of beef flank,shoulder and eyeround were observed arranged compactly,while chicken breast,pork loin and beef tenderloin were arranged loosely.The results of magnetic resonance imaging showed that the six kinds of animal meats three different water types,including protein-binding water,freezable water(myofibril inner water),and free water(myofibril outer water).Water was evenly distributed in chicken and pork while unevenly distributed in four kinds of beef which contained more fat than others.Besides,the content and distribution of different water states affected the texture properties of meets.The microstructure of meat had a certain correlation with its texture and digestibility.The meat with closely arranged fiber bundles had higher hardness and chewability,and lower digestibility.The results in the current work provide scientific basis for the establishment of quality evaluation standards of plant-based meat analogue products.