How strong does the vacuum have to be to compress fruits?

Marek_30573

The question is the same as the title, how strong does the vacuum have to be to compress fruits?
I am about 70% into building a vessel meant for compressing fruits. I am hoping for 90-92% vacuum, will it be enough to achieve the desired effect?
If not then knowing it now would save me some money that would go to waste otherwise.

SteveM_20803

Let me start out by saying I am by no means an expert on this.  I don't think there is enough information to answer your question in your statement above.  I have seen vacuum measured in bars, mbars  and Hg, they are relative to what normal atmosphere is.  I'll have to double check but I think my sealer gets down to -1.0 bars. I can check when I get home tonite.

But more importantly, what you need to achieve to enough negative pressure that the air trapped in the cells of fruit escape.  When they do, they damage the cell walls.  When the fruit returns to normal air pressure the cells deform or are filled with the juice; they compress.  Your device needs to pull enough vacuum that you not only remove the pressure from the chamber, but also pull air through the cell walls of your fruit. 

I am sure there is a more technical explanation for all of this, but this is the gist of what I remember reading.