Thread: The PA scale
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Default The PA scale

"frederick ploegman" > wrote in message >...
> Ray
>
> We have _lots_ of experts in this group, and these experts have access
> to a wide variety of references. So why don't we just ask the folks
> here _point blank_, and see what they can come up with.
>
> Earlier, Andy wrote:
> "...My literature from UC Davis says (paraphrasing):
>
> The theoretic maximum yield of ethanol is around .6 times the initial
> Brix. This would give a maximum yield of 13.2 ABV for a 22 Brix must.
> My reference goes on to say that .55 times the initial brix is really
> all we can get in practice, which would yield around 12.1 ABV. This is
> because a varying percentage of the sugar is used for other things and
> even if the fermentation does not stick, there is a percentage of
> sugar that ends up as other end products (like glycerol, pyruvate,
> acetate, acetaldehyde)...."
>
> **Question to the group: Does _anyone_ out there have any modern
> reference that_contradicts_what UC Davis has to say on this subject
> in any substantive way ????? TIA
>
> Frederick
>


Margalit, who was already mentioned in this thread, has higher values.
In Concepts of Wine Chemistry, p. 57 - maximum theoretical yield comes
out as 65% by volume, average practical yield is estimated as 57% of
B, with references to literature that report experimental data in the
values of the actual measured yield of 55%-60% B.

Regards,

Pp