HI 83741

Photometer for the Determination of Iron in Wine

Significance of Use

Trace iron concentrations in wine are beneficialfor enzyme activity, as a stabilizer, and as a functional component for proteins.At higher concentrations it alters the redoxpotential, in favoring oxidation, affecting sen- sory characteristics and participating in the formation of complexes with tannin and phosphates resulting in instabilities (casse). The most common iron case is “white casse” (iron phosphate), it is initially seen as milkywhite cloud and later as a precipitate. The “bluecasse”(ferric tannate) that occurs less often can be observed in white wines, for example, after tannic acid additions.Most of the iron present in wine is present inthe ferrous Fe(II) state. The ratio of the Fe(II)/Fe(III) depends on the oxidation state of wine. If Fe (III) is formed, it can bind with phosphates that are normally present in wine.Since iron strongly binds with several organicacids, some wine makers add citric acid to the wine to complex free iron in wine is contact with iron in wine is contact with iron containing alloys during processing. During fermentation a part of the iron is absorbed by yeast and thus removed from the wine during filtration. HI 83741 is supplied with reagents for 5 tests, 1000 µlpipette, 1 mL pipette, (2) cuvets with caps, tissue for wiping cuvets, scissors, 12 VDC power adapter, (4) 1.5V AA batteries and instruction manual in a hard carrying case.

Reagents and AccessoriesOrdering information

Reagents HI 83741-20 (20) Iron reagents Accessories HI 731318 (4) Cuvet tissues HI 731341 1000 µL pipette HI731351 (25) 1000 µL plastic tips for automatic pipette HI 731321 (4) Glass cuvets HI 731325W (4) Caps for cuvets HI 93703-50 Cuvets cleaning solution HI 710006 12 VDC power supply HI 740027P (10) 1.5V AA batteries Casse formation depends on: iron concentration, pH, ORP, phosphate, content and the type of wine white casse formation white casse inhibition iron concentration > 7 ppmhigh redox potential (Fe3 + present)ph 2.9-3.6 iron concentration < 5 ppmclarification with bentonitecitric acid addition 12-24 g/hL

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HANNA instruments®

Wine TestingCatalog