Eight craftsmen Ding Songren reminds everyone that the atmosphere turns cool, pay attention to adding clothes... So let's get into today's topic:
According to the effect used in the actual production and the characteristics of the action of the amylase preparation, there are three methods:
1. Mixed heating method:
Added at the same time as the excipient is added, so that the amylase can be fully dispersed and free in the mash, with the increase in the temperature of the excipient mash, the speed of action of the enzyme is also accelerated, until the mash temperature gradually reaches and exceeds the inactivation temperature of the enzyme, the enzyme stops acting.
This addition is very convenient, and the liquefaction effect is still good, but you need to pay attention to the following problems:
(1), the excipients must be crushed relatively fine, in order to quickly gelatinize and liquefy, otherwise it will be due to the coarseness of the starch particles, easy to cause "peeling gelatinization" (that is, large starch granules layer by layer gradually gelatinization and liquefaction), so that after the enzyme inactivation, the starch has not been liquefied completely, so that the mash is still thick;
(2), should be selected in the same kind of excipients in the gelatinization temperature of the low varieties, because the gelatinization temperature of excipient varieties, starch gelatinization critical temperature will also make some enzymes inactivated or passivated, plus gelatinized mash of the material water ratio is generally relatively large, amylase preparation heat resistance performance will be reduced, so that just in the gelatinization temperature of the excipient gelatinization effect in the rapid progress, the enzyme has been gradually inactivated, thereby affecting the liquefaction effect;
(3), when using the mixed liter method, you can consider adding some calcium ions (gypsum or calcium chloride) to protect the role of enzyme preparations, you can also consider pre-immersion of excipients, so that the excipient starch fully absorbs water and expands, improve the effect of enzymes.
2. Intermediate input method:
First mix the excipient powder with the water and then put it into the gelatinization pot, the feeding temperature is slightly higher (for example, about 60 ° C), and then the temperature is heated up according to the specified heating rate, when the mash temperature is close to the appropriate temperature of the amylase preparation, the enzyme preparation is mixed into a uniform dilute slurry solution, and slowly poured into the gelatinized mash (the liquid enzyme preparation can be directly poured).
Because the enzyme solution heats up instantaneously when it comes into contact with gelatinized mash, the speed of action of the enzyme is sharply accelerated, that is, the expanded gelatinized starch colloidal solution can be quickly liquefied.
Using this method is a bit more troublesome, plus the gelatinized mash is thicker and the dispersion of the enzyme is poorer.
In addition, bacterial amylase is a powder, which is easy to cause the scattering of bacterial spores in the enzyme preparation when sizing, and the effect of this method is acceptable.
There are several issues to be aware of when using this method:
(1), the material-water ratio is larger (5:1 or more), so as not to gelatinize the mash into a starch adhesive solution is too thick, affecting the dispersion of enzymes, resulting in poor effect;
(2), relative to the mixed heating method, this method is slightly less affected by the gelatinization temperature and crushing degree of the excipient, but it must be strengthened to prevent the mash from sticking;
(3), the amount of enzymes may be slightly higher, it is best to use 7 to 8u per 1g of liquefaction excipients. Of course, it is better to use 5 ~ 6u to meet the liquefaction requirements.
(4), the heating rate should not be too fast, in order to ensure that the excipient starch can fully absorb water and expand and rupture, to meet the requirements of gelatinization.
3. Instantaneous action method:
This approach can take two forms.
A kind of first in the gelatinizing pot with about 2/3 of the water heating heating, and in another pot will be the excipient powder and enzyme preparation with the rest of the water (about 1/3) for slurry, and evenly mixed, when the water temperature in the gelatinization pot reaches 90 ~ 95 ° C, with the pump will be this enzyme and excipient mixed slurry fan-shaped dispersion pump into the hatching pot, so that the excipient powder can be in contact with high temperature water at the moment, rapidly absorb water expansion gelatinization, while quickly by enzymatic action and liquefaction due to the pre-immersion of the excipients during the slurry process, Therefore, the effect of gelatinization and liquefaction can be improved.
Another method is to adjust the form of the slurry unchanged, but the amount of water can be used almost to the specified water consumption ratio of the material and water, and then the slurry is pumped into a special high-pressure nozzle, and the high-temperature steam is introduced into the nozzle site, so that it is rapidly heated up for instantaneous gelatinization and liquefaction.
These two forms have a short action time and a good effect, but they need to meet the following conditions:
(1), the excipient powder must be crushed very finely, over 60 mesh or 80 mesh fine powder to no less than 80% as well, so that it can quickly absorb water at the moment of contact heating up, gelatinization and liquefaction, otherwise the effect is not good, the use of the second form is also easy to block the nozzle;
(2) Another slurry tank needs to be prepared, and a stirrer, sprinkler and pump should be prepared;
(3), the use of high-temperature steam should pay attention to control its purity, or be appropriately treated, nozzle, slurry tube, steam pipe should use stainless steel.
The above three methods can be selected according to the conditions and effects of the factories using bacterial amylase preparations.
However, in order to improve the liquefaction effect, when using the mixed heating method and the intermediate input method, it can be added according to the proportion of 8 to 10g excipient powder per ·g malt powder liquefaction, and the appropriate amount of malt powder is first put into the gelatinization pot, and attention is paid to 70 ° C for 10 to 15 minutes to use it as a means of liquefaction of excipients to ensure the liquefaction of excipient mash.
In this case, the amount of bacterial amylase can be appropriately reduced (calculated by 1g excipient powder with enzyme 3~ 4u).
If high-temperature amylase can be used, any of the above methods can be used, and the various conditions required are not very strict.