ULO (Ultra Low Oxygen) Atmosphere
DCA (Dynamic Control Atmosphere)
Like the name itself says, it is a process of dynamically changing the amount of oxygen in the chamber. The process of this storage principle is to create a chamber that has a very low concentration of oxygen O2, less than 0.5%, and with a carbon dioxide concentration of CO2 less than 1%. In such conditions, the fruit radically changes its metabolism.
In a normal atmosphere which consists of about 20.8% of oxygen O2, the sugar C6H12O6 is stored in the fruit, and due to the breathing effect, it is combined with oxygen, which is shown in the formula:
C6H12O6 + O2 = CO2 + H2O + Heat
Sugarr + Oxygen = Carbon Dioxide + Water + Energy
M e t a b o l i z a m
The essence of a controlled atmosphere is to reduce the percentage of oxygen in the chamber so that the metabolism of the fruit slows down and thus extends its life.
Using stress with a drastic reduction of oxygen causes a process of preservation on the one hand, and on the other hand changes breathing in accordance with the following formula:
C6H12O6 + O2 (less than or equal to 0.5%) = C2H5OH + CO2 + Aldehydes
Sugar + ultra low oxygen = alcohol + carbon dioxide
This is why it is important to do the analysis of alcohol in the pulp directly from the juice sample, as the fermentation beggins when the percentage of O2 falls below 1%. And this is the only and safest way of analysis caused by stress.
At the end of the First Stress, O2 returns to 1 – 1.2%. In these conditions, the fruit begins to slowly breathe without stress and is kept safe without risk. Once the alcohol disappears, the Second Stress phase begins with the same goal of prolongation of storage. The same principle is used as in the First Stress Phase, etc. … During the storage, it is allowed to stress the fruit maximum 3 times, after which the fruit returns to conditions where the level of O2 returns to over 1%.