Vacuum oxygen reduction after the bottle, can prevent the oxidation of the ingredients, active, stable and inhibit microbes survive, so it can extend the storage time.
But maintain article is liquid, can't like solid is completely pumping air into vacuum state, therefore to extend the time is limited.
In fact, most looked sealed packaging are not vacuum.
Distinguish the vacuum flask of stoma, see the bottom of the bottle, there is no is not.
Covered the smoke hole, can cause can't squeeze.
Most of the seal is dropped the residual air pump after production, is not really that vacuum.
And our common spray is the design of the pressurized with nitrogen to the bottle, is not a vacuum.