| Analyte. |
Cat. No |
Analyte Significance |
Advantages of Megazyme Test Kits |
| Acetaldehyde |
K-ACHYD |
A sensory compound that adds flavour and
complexity, but spoils wine at high concentrations |
AcDH supplied as a stabilised solution rather than a
lyophilised powder, thus less wasted enzyme |
| Acetic Acid |
K-ACET
K-ACETAF
K-ACETAK
K-ACETRM |
A sensory compound that adds flavour and
complexity in small amounts, but spoils wine at
high concentrations. Produced naturally by yeast
in small amounts and by spoilage organisms such
as Acetobacter aceti in large quantities.This is the
predominant of the acids comprising ~ 85 % volatie
acidity (VA) |
All kits contain PVP to prevent tannin inhibition.
1. K- ACET (manual, efficient) constains stable ACS suspension
2. K-ACETAF (auto) very stable R1 and R2
3. K-ACETAK (auto) is a stable, and very rapid acetate
kinase (AK) based kit with excellent linearity
4. K-ACETRM is a rapid, manual assay kit employing AK
and phosphotransacetylase
Stable reagent |
| Ammonia |
K-AMIAR
K-LARGE |
Most important inorganic source of Yeast Available
Nitrogen (YAN) |
Novel enzyme employed is not inhibited by tannins,
endpoint reaction time ~ 3 min. Ideal for manual and auto-
analyser applications |
| L-Arginine |
K-LARGE |
Most important amino acid in grape juice with
respect to YAN |
Simple and rapid test kit gives sequential values for
ammonia, urea and L-arginine. No tannin inhibition |
| L-Ascorbic Acid |
K-ASCO |
Present naturally in grapes and can be added as an
anti-oxidant |
Rapid reaction, stable reagents |
| Citric Acid |
K-CITR |
Naturally present in small amounts; large amounts
indicate addition for acidification
(EU limit is 1 g/L) |
Ideal for both manual and auto-analyser applications.
Reconstituted citrate lyase stable for > 6 months at -20°C.
Stable reagents |
| Ethanol |
K-ETOH |
Produced during alcoholic fermentation.
Amounts > 17.5 % (v/v) indicate supplementation |
Rapid reaction, stable reagents (AlDH supplied as a stable
suspension) |
D-Fructose /
D-Glucose |
K-FRUGL
K-FRGLMQ
K-FRGLQR |
Grape quality indicator. One of the two principle
fermentable sugars of grape juice |
Contains PVP to prevent tannin inhibition. Ideal for manual
and auto-analyser use. Stable reagents |
D-Gluconic
Acid |
K-GATE |
Grape quality indicator for the production of
certain wines |
Rapid reaction, stable reagents |
| Glycerol |
K-GCROL
K-GCROLGK |
Quality indicator of finished wine, important for
“mouth feel” |
Novel tablet format offers superior stability, rapid reaction |
| D-Lactic Acid |
K-DATE
K-DLATE |
Produced predominantly by lactic acid spoilage
bacteria |
Rapid reaction, stable reagents |
| L-Lactic Acid |
K-LATE
K-DLATE |
Produced predominantly from L-malic acid during
malolactic fermentation |
Rapid reaction, stable reagents. Ideal for manual and auto-
analyser applications |
| D-Malic Acid |
K-DMAL |
Only present in significant quantities in adulterated
wine |
D-MDH supplied as a stabilised suspension rather than a
lyophilised powder, thus less wasted enzyme |
| L-Malic Acid |
K-LMALR/L
K-LMALAF
K-LMALMQ
K-LMALQR |
Grape quality indicator. Very important grape
acid, converted to less acidic L-lactic acid during
malolactic fermentation |
All kits contain PVP to prevent tannin inhibition.
1. K-LMALR/L (manual) rapid reaction
2. K-LMALAF (auto) rapid reaction, excellent linearity
3. K-LMALMQ (manual, colorimeter based)
4. K-LMALQR (auto) liquid ready reagent |
Primary Amino
Nitrogen (NOPA) |
K-PANOPA |
Primary amino nitrogen (PAN) is the most
important organic source of YAN |
Novel kit, rapid reaction, stable reagents, simple format |
| D-Sorbitol |
K-SORB |
High levels indicate addition of fruit |
Diaphorase supplied as a stabilised suspension rather
than a lyophilised powder, thus less wasted enzyme |
| Succinic Acid |
K-SUCC |
Wine acid produced during fermentation |
Rapid reaction (~ 6 min even at room temperature), stable
reagents |
| Sucrose |
K-SUFRG
K-SUCGL |
Added to increase the amount of alcohol.
Use only permitted in certain situations |
Choice of simple formats available, based either on glucose
oxidase / peroxidase, or hexokinase / G-6-PDH |
| Sulphite |
K-SULPH
K-TSULPH
K-ETSULPH |
Sulphites are used as an essential additive in the
control of microbial contamination during aging
and to also protect the wine against detrimental
“oxidative and enzymatic browning” |
Choice of simple formats available, based either on liquid
ready reagent chemical reactions (K-SULPH & K-TSULPH)
or an enzymatic reaction (K-ETSULPH). Stable reagents |
| Tartaric Acid |
K-TART |
Occurs naturally in grapes and is one of the most
prevalent organic acids. Key indicator of total
(titratable) acidity (TA) |
Stable liquid ready reagents. Simple, rapid chemical
reaction for manual, auto-analyser and microplate formats |
| Urea |
K-URAMR |
Source of YAN and precursor of the carcinogen
ethyl carbamate. Over-supplementation with DAP
can result in elevated levels |
Simple, very rapid (both urea and ammonia measured in
< 10 min at room temperature) and sequential / efficient
(only one cuvette required per sample) |