4
The
HI 83740
is an auto-diagnostic portable microprocessor meter that benefits from Hanna’s
years of experience as a manufacturer of analytical instruments. It has an advanced optical system
based on a special tungsten lamp and a narrow band interference filter that allows most accurate
and repeatable readings. All instruments are factory calibrated.
The auto-diagnostic feature of this meter ensures always optimal measurement conditions to
ensure most precise readings. The light level is automatically adjusted each time a zero-measurement
is made, and the temperature of the lamp is controlled to avoid overheating.
GENERAL DESCRIPTION
Grapes accumulate normally only a small amount of copper by natural translocation from roots.
Unless exposed to significant airborne pollution or vineyard sprays, increased concentrations in wine
result from contamination during post-fermentation processing, like contact with non stainless steel
equipment and as impurities in fining agents and filter media.
The copper concentration in wine is normally low, less than 0.10 to 0.30 mg/L, because excess copper
is precipitated during fermentation due to adsorption onto the yeast cells. This adsorption and precipi-
tation can reduce the initial copper concentration with 40 to 89%. At higher concentration copper
plays an important role in catalysing oxidation reactions of wine phenols.
It is important to check the copper content both in must and in wine, because at levels above 9 mg/L
copper becomes a metabolic toxin that inhibits or delays alcoholic fermentation, and concentrations
exceeding 1 mg/L may be sensorial detected and should be avoided.
Other copper related problems can be manifested as formation of white haze (in white wines) and
later as a reddish-brown amorphous precipitate. This precipitated ‘casse’ develops only under the
strongly reducing conditions found in bottled wines. It has been found that this casse is a mixture of
copper compounds and proteins.
Factors favouring and inhibiting copper casse formulation in wine
Necessary conditions
Preventive
for copper casse formation
Measures
strong reducing conditions
copper levels at less than 0.3 mg/L
low iron concentrations
limit SO
2
addition
high protein levels
cold-stabilize and bentonite fine to reduce proteins in white wine
light and heat
SIGNIFICANCE OF USE
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Battery replacement must only take place in a non-
hazardous area.
The blinking “ ” will appear when the batteries power
gets low.
When batteries are completely discharged, “0% bAtt”
will appear and after two seconds the instrument is
switched off.
Remove the battery cover from the bottom of the
instrument and change the old batteries with 4 fresh
1.5V batteries, paying attention to the correct polarity.
Replace the cover.
BATTERIES REPLACEMENT
REAGENT SETS
HI 83740-20
Copper reagent set for wine (20 tests)
HI 83742-25
Color Reagent Set for wine (Wine Solvent-1)
OTHER ACCESSORIES
HI 740027P
1.5V AA batteries (10 pcs)
HI 731318
Tissue for wiping cuvets (4 pcs)
HI 731321
Glass cuvets (4 pcs)
HI 731325W
Caps for cuvets (4 pcs)
HI 93703-50
Cuvets cleaning solution (230 mL)
HI 740231
20 mL glass cylinder with caps (2 pcs)
ACCESSORIES