Processing Technology for High Viscoelastic Surimi Products (Part One)
When processing and making various surimi foods, the choice of fish species and the freshness of the fish are very important; they affect the elasticity of the product, so in surimi raw materials, there is a certain limit to the amount of soybean and @#@245@#@ protein powder mixed in; too much will weaken the elasticity of the product. In order to solve the elasticity problem of aquatic surimi products, a new method is adopted in which fish protein alone or mixed with plant protein is made into protein fibers, and then mixed with surimi to produce surimi foods with excellent viscoelasticity, which can enhance the elasticity of Grade C low-quality surimi to above Special Grade A.
Production method: after the raw fish is deboned and its meat collected, it is minced with a meat grinder, water and alkali are added to bring the pH to the range of 9-12, and the protein is extracted through continuous stirring; then a centrifuge is used to separate out the insoluble residue, after which hydrochloric acid, acetic acid, etc. are added to adjust the pH to 4-6 so that the protein precipitates at its isoelectric point, and then a centrifuge is further used for separation to obtain a protein curd.
Water is added to the prepared protein curd to adjust the protein concentration to 5-20%, then while adding alkali, a stirrer is used to mix it evenly to make an alkaline sol solution with a pH of 10-13. This solution is extruded through fine small holes into an acidic coagulating liquid made of acid and salt to form fibers, then after decolorization and deodorization treatment, it is washed with alkali or water and the pH is adjusted to 6-7, thus obtaining protein fibers.
The prepared protein gel can also be mixed in an appropriate proportion with protein curd made from plant proteins such as defatted soybean, then water is used to adjust the protein concentration to 10-20%, and protein fibers are made according to the above method.
For the raw material for making fish protein fibers, any edible fish can be used. For the raw material for plant protein fibers, proteins from grain and oil seeds such as soybean and peanut, as well as wheat protein, etc., can be used.
The prepared protein fibers can be mixed with minced fish meat in any proportion (but cannot be used alone) to make surimi foods. When using, the protein fibers can first be mixed with minced fish meat and then ground and kneaded; or the minced fish meat can first be ground and kneaded, then the protein fibers added, and then ground and kneaded again.
Example 1: After collecting the meat of crucian carp, it was minced with a meat grinder; while stirring, water and caustic soda were added to adjust the pH to 11 to extract protein; after removing insoluble residue with a centrifuge, hydrochloric acid was added to adjust the pH to 5.5 to precipitate the protein, and then a centrifuge was used for separation to obtain a protein curd. Water and caustic soda were added to the prepared protein curd to adjust the protein concentration to 7% and the pH to 12.2, making an alkaline sol solution, which was extruded through micropores with a diameter of 0.6 mm into a coagulating liquid made of 5% hydrochloric acid and 10% table salt; after neutralization and water washing, an edible protein fiber with a moisture content of 83% was made.
Take 50 parts each of the prepared protein fiber and Grade C frozen surimi of Alaska pollock and mix them, add 3 parts of table salt, grind and knead with a grinder-kneader for 20 minutes, then add 1 part of monosodium glutamate, 2 parts of sugar, and 3 parts of starch, grind and knead again, then shape, and steam at 80°C for 30 minutes. The viscoelasticity of the product is better than surimi foods made with special-grade surimi (without added protein fiber).
Example 2: According to the method of Example 1, a protein curd with 24% solid content was made from Alaska pollock.
Separately, defatted soybean was added to 10 times its amount of water and caustic soda, the pH was adjusted to 10, protein was extracted through continuous stirring, insoluble residue was removed with a centrifuge, hydrochloric acid was used to adjust the pH to 4.5 to precipitate the protein, and then a centrifuge was used for separation, thus obtaining a soybean protein curd with 22% solid content.
Equal amounts of the two protein curds were mixed, water and caustic soda were added to make an alkaline sol solution with a protein concentration of 12% and pH 12.3, which was extruded through fine micropores with a diameter of 0.5 mm into a coagulating liquid containing 5% hydrochloric acid and 10% table salt; after neutralization and water washing, an edible protein fiber with pH 6.8 and 75% moisture was obtained.
Take 50 parts of the above protein fiber and grind and knead it, add 50 parts of Grade A minced Alaska pollock meat, 2.5 parts of table salt, and 1 part of monosodium glutamate, then fully grind and knead and mix, add 5 parts of starch, 3 parts of mirin, and 20 parts of ice water, and grind and knead again.
The prepared raw material is wound around iron skewers and grilled for 5 minutes, thus producing a tube-shaped fish roll with excellent texture and flavor.