Chinese ancestors actually discovered the production method of tofu, which is one of the most amazing discoveries in history, as the saying goes, "brine point tofu, a thing of a thing", otherwise we still can only drink soybean milk, this brine is how to make the soybean milk into the tofu brain, followed by the concentration of the said tofu?
What is brine in the end? How does it make soy milk into tofu?
General brine is actually easy to be misunderstood, because a lot of brine with a lot of people also known as brine, that kind of brine is a variety of edible spices modulation, is not discussed in this article, and the real brine is salt brine, which is seawater or salt lake water salt production, residual in the salt pond after the evaporation of the mother liquor cooled, precipitation crystal and the formation of brine block. The main components are magnesium chloride, sodium chloride, potassium chloride, calcium chloride, magnesium sulfate and magnesium bromide.
Halogen block
Halogen block is also very salty, mixed with tofu in a small amount of food can supplement the trace elements, but never overdose, will be poisoned, on the skin, mucous membranes irritation is very strong, on the central nervous system has a depressant effect, people such as accidentally accidentally served, there will be nausea and vomiting, dry mouth, abdominal distension, diarrhea, dizziness, headache and other symptoms!
How in the world is the brine point tofu?
The soybeans are ground and washed in water to dissolve the proteins, then boiled in water, not at a rolling boil, of course, but slightly bubbling! After skimming off the foam that floats to the surface, what's left in the big pot is pretty much a mixture of protein and water! At this point, the soy protein particles are surrounded by water and constantly moving, can not be gathered together, the formation of a "colloid"!
Soy protein surface with free carboxyl and amino groups. These groups on the role of water, so that the surface of the protein particles to form a layer of the same charge with a film of water colloidal material, which the repulsive force so that the particles are separated from each other, will not be bonded into a group!
Salt brine is mainly magnesium chloride (MgCl2), these solutions belong to the electrolyte solution, in the water will form a lot of charged particles (positive ions and negative ions), the hydration of these ions seized the protein water film, so that proteins are isolated, in addition to the positive and negative ions of magnesium chloride electrolytic solution inhibited due to the surface of the protein charged with repulsive force, which makes the particles coalesce with each other. This results in a blob of beanflakes!
Of course, this requires a certain amount of time, this waiting time is known as the squatting brain, also known as the rising pulp or pulp, just point of brine in the protein peptide chains and peptide chains and peptide chains and water molecules, it takes time to form a homogeneous and orderly three-dimensional structure, at this time it is not suitable for stirring and vibration, or else the rate of tofu is low or can not form the soybean flower.
Congealed into a ball
Of course the role of the salt brine can only form the soya bean flower, the next tofu need to be further tawdry operation to be able to, that is, the press, the water will be filtered out, and then pressed in the gauze, squeezing out the excess water, the formation of soya bean curd!
The brine-pointed tofu is just a process of colloidal polymerization and sinking, not a chemical reaction.
A few tofu dishes
What else besides brine turns soy milk into tofu?
We usually eat tofu in the old tofu and tender tofu, turnip greens have their own favorite well, the old tofu with brine, tender tofu is gypsum. As we have seen above, as long as the conditions for protein coagulation are met, other substances can also be used as catalysts for tofu!
The one that fits this bill can be gypsum, which is calcium sulfate! There's also glucono-delta-lactone, which is called lactone tofu! Even white vinegar works, and there are friends who can order tofu with lemon juice, so many of you who prefer all-natural make tofu with lemon juice! There are also tutorials online for those who are interested in learning about it!
Of course with the principle of changing the PH value is slightly different, but the addition of acid will make the protein colloidal particles between the convergence of the isoelectric point (soy protein for Glycinin, beta-Conglycinin, isoelectric point about the PH5 or so), the colloidal particles of the net charge is reduced, the smaller the repulsion, easy to cohesion of the clusters, the result is in fact the same.
Extended reading: Bean curd (tofu skin)
Tofu skin is boiled soybean milk to keep the pot open, and then soy protein on the surface of the cooling crust formation, the production process is much simpler than the tofu, experienced friends will be in the tofu before pulling a few sheets of soybean skin, of course, the soybean skin pull more, out of the tofu rate is to decline, but an operation, two delicious, is not it is very worth to try it!
The edges of the pot zou up is the beanskin, with chopsticks to fish up
The beanskin is the material to do spring rolls, or to do soup, or to do the meat skin rolls, is a necessary ingredient! You do tofu may not have the courage to try, but the bean skin is too simple, the next time you cook soybean milk into a large pot, prepare a few chopsticks or special to get a few long clean small bamboo can also be, and then find a drying place, drying can be!
Lastly, sodium chloride solution is also an electrolyte solution, it can also point tofu, just the amount to be very large, out of the tofu salty death you!