天然肠衣是用猪、牛、羊等动力的消化系统或泌尿系统的脏器加工而成，加工办法不一样，分为盐渍肠衣和干制肠衣两种；天然肠衣呈浅赤色、白色或乳白色，干制肠衣多为淡黄色、具有必定香气。肠衣直径每路隔2mm,自24～40mm等；盐渍肠衣在运用前要仔细浸泡清洁，不然会在熟加工后会发生盐霜。 Natural casing is made of pigs, cattle, sheep and other power of digestive system or urinary organs and processing method is different, divided into two kinds of salted casing and dried casing; The natural casing is pale red, white or milky white, and the dry casing is light yellow and has a certain aroma. The casing is 2mm in diameter, from 24 to 40mm. The salt-stained casing should be carefully soaked before being applied, or it will be salted when cooked. 　　长处：弹性好，保水性，具有较好的安全性、可食性、水气透过性、烟熏味进入性、热缩短性和对肉馅的黏着性，还有杰出的耐性的坚实性，营养价值高。 Strengths: good elasticity, water retention, has good safety, edibility, moisture permeability, smoky into, heat shorten and adhesion of meat, and great patience solid, high nutritional value. 　　缺陷：标准和形状不整齐，数量有限，并且在加工和储存不其时易遭虫蛀，呈现空泛和易蜕变变味。 Defects: the standard and the shape are irregular, the quantity is limited, and the processing and storage are not at the time easy to be infected by the worm, the appearance of the empty and easy to change the taste. 　　2、组成肠衣，即人工肠衣，即把动物皮、塑料、纤维、纸等加工成的片状或筒状薄膜，包含以下几种： The composition of the casing, namely the artificial casing, which is a sheet or tubular film that is made of animal skin, plastic, fiber, paper, etc. 　　（1）纤维素肠衣：用天然纤维如棉绒、木屑、亚麻和其他植物纤维制成。 (1) cellulose casing: made from natural fibers such as cotton flannel, wood chips, flax and other plant fibers. 　　长处：具有极好的耐性和透气性，在疾速热处理时也很安稳，在湿润的情况下也能熏烤，上色。 Advantage: excellent patient and breathability, also very stable in heat treatment, also can be smoked when wet, colour. 　　缺陷：不行食用，不能随肉馅缩短。 Defect: not edible, can not follow the meat filling shorten. 　　（2）胶原蛋白肠衣：用牲畜的皮、肌腱等为质料制成。 (2) collagen casing: made from the skin of livestock and tendons, etc. 　　长处：可食用，料粗时也不宜食用；透气性好，易上色。 Strengths: edible, not edible when coarse. Good air, easy to colour. 　　缺陷：在热加工时要注意加热温度，不然会变软。 Defect: pay attention to heating temperature when processing heat, otherwise it will become soft. 　　（3）塑料肠衣：一般用作外包装肠衣或商品定型。 (3) plastic casing: usually used as an outer packing casing or product set. 　　长处：具有隔绝空气和水透过的性质和较强的耐冲击性，种类标准多，能够印刷，运用方便，光亮漂亮，适合于蒸煮类商品。 Strengths: through isolated from air and water and strong resistance to impact, the properties of kinds of standards, can printing, use convenient, bright beautiful, suitable for cooking class goods. 　　长处：不能食用。 Strengths: not edible. 　　（4）玻璃纸肠衣：是一种纤维素薄膜，纸质柔软而有伸伸缩性，其纤维素微晶体呈纵向平行摆放，故纤向强度大、横向强度度小。 Pt casing (4) : is a kind of cellulose film, paper is soft and has stretched to scalability, the cellulose micro crystal is parallel to the longitudinal put, so the fiber to strength and transverse strength is small. 　　长处：本钱比天然肠衣低。 Advantage: the money is lower than the natural casing. 　　缺陷：运用不当易决裂 Defects: the use of improper and unbroken