- Forgive my n00bness, but as a brewer of other libations, I am always
worried about stuff being 'light-struck', is this not a problem with
mash for fermenting? On the other hand, I brew in glass, maybe people
don't use that... finally time to get my steel conical?
- --- In email@example.com, "jfpf92" <JamesPerryUSA@...>
>It is certainly something to be aware of. But light strike
> Forgive my n00bness, but as a brewer of other libations, I am always
> worried about stuff being 'light-struck', is this not a problem with
> mash for fermenting? On the other hand, I brew in glass, maybe people
> don't use that... finally time to get my steel conical?
(aka 'skunked' beer) is not really a problem. Many of our distiller's
mashes (for whisky) are essentially a young beer without hops, and
therein lies the secret.
What does light-struck mean?
This is when the beer has been exposed to ultraviolet light for a
period of time. Hop-derived molecules, called isohumulones, are
basically ripped apart by UV. Some of these parts bind with sulfur
atoms (yeast metabolites) to create that "skunk" character, which is
similar in character to a skunk's natural defense and is such a potent
compound that parts-per-trillion can be detected and even ruin a beer.
It's been said that bottled beer can become light-struck in less than
one minute in bright sun, after a few hours in diffuse daylight, and in
a few days under normal fluorescent lighting.
But in order for this to happen at all, the beer needs to contain
HOPS! No Hops = no isohumulones = no 'skunk'. And that's another good
reason NOT to use ordinary beer or brewers returns as a still
--- In firstname.lastname@example.org, "Harry" <gnikomson2000@...> wrote:
> But in order for this to happen at all, the beer needs to contain
> HOPS! No Hops = no isohumulones = no 'skunk'. And that's another good
> reason NOT to use ordinary beer or brewers returns as a still
> charge. :)
> regards Harry
Further info on Light-Strike here...
- I guess that makes sense for grain-only, however I did note that wines
can be struck (and in my experience meads/pyments can be too,
"Lightstruck wines are those that have had excessive exposure to
ultraviolet light, particularly in the range 325 to 450 nm. Very
delicate wines, such as Champagnes, are generally worst affected, with
the fault causing a wet cardboard or wet wool type flavour and aroma.
Red wines rarely becomes lightstruck because the phenolic compounds
present within the wine protects it. Lightstrike is thought to be
caused by sulfur compounds such as dimethyl sulfide. In France
lightstrike is known as "goÃ»ts de lumiÃ¨re", which translates to tastes
of light. The fault explains why wines are generally bottled in
coloured glass, which blocks the ultraviolet light, and why wine
should be stored in dark environments."
Just FYI, not trying to one-up....