Glucose + Fructose
Glucose + Fructose are measured using the FOSS FTIR Winescan or the Randox Daytona enzymatic analyser. This may also be measured in combination with organic acids by HPLC.
The Rebelein method provides a method of determining the reducing sugars present in wine and grape juice samples. This method involves reacting the reducing sugars present in these sample with excess alkaline cupric (Cu++) tartrate, from which the concentration of reducing sugars is determined from the amount of Cu++ remaining after reaction. The Cu++ remaining can be determined by reducing the Cu++ with iodine (2Cu++ + 2I– → 2Cu+ + I2) and estimating the remaining iodine with standard thiosulphate solution (I2 + 2S2O32- → 2I– + S4O62-).
Brix is measured using a digital refractometer and can easily be converted to baumé by dividing the brix result by 1.8.
A FOSS FTIR Winescan density meter may be used to measure specific gravity. Specific gravity is a requirement of some export certificates.
|Prices per analysis|
|Analysis||Per Sample (excluding GST)||Volume required||Target response time|
|Glucose + Fructose by Winescan||$10||50 mL||24 hrs|
|Specific Gravity by Winescan||$10|
|Brix / Baumé||$10||10 mL or 200 berries||24 hrs|
|Sucrose by Rebelein||$35||25 mL||24 hrs|
|Reducing Sugar by Rebelein||$25|
|Glucose + Fructose by Daytona||$30||10 mL||24 hrs|
|Specific gravity by density meter||$20||25 mL||24 hrs|
For more information, please contact AWRI Commercial Services on (08) 8313 6600 or e-mail email@example.com