Agriculture Reference
In-Depth Information
level of 33 ppm and I want to reduce the sulfite level to 15
ppm before adding a malolactic culture, I need a reduction of
33ppm−15 ppm or 18 ppm. The amount of 3% hydrogen
peroxide solution to add is calculated like this:
(Gallons of wine) × (ppm reduction desired) = ml of 3%
hydrogen peroxide solution to add
So 5 gallons × 18ppm = 90ml of 3% hydrogen peroxide
solution.
Yeast
Yeast is the star of the show. Wild yeast naturally colonizes
the surfaces of fruits, so sometimes crushed fruit, left to its
own devices and protected from other organisms, will ferment
all by itself. In fact, this is the case in certain famous wine
regions where the wild yeasts inhabiting the area have
co-evolved with the wine grapes. Though most wine yeasts
are of the species Saccharomyces cerevisiae, there are
hundreds if not thousands of variations of this species, some
with dramatically different properties. The genome of wine
yeast has over twelve million base pairs, making for
substantial possibilities for variation.
In practice, wine makers do not rely on wild yeasts because
the unpredictability can often result in serious failures or
faults in the finished product. Instead, wine makers usually
purify the musts of wild yeasts and bacteria by adding sulfite.
Once the sulfite has been added, the must is stirred
thoroughly and then allowed to sit for a day before a cultured
wine yeast of known character is added.
Search WWH ::




Custom Search