Hanna Instruments HI 83740 User Manual

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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

addition

high protein levels

cold-stabilize and bentonite fine to reduce proteins in white wine

light and heat

SIGNIFICANCE OF USE

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