For the measurement of sucrose, lactose and D-glucose in flour mixtures and other materials. (100 assays of each per kit).
INTRODUCTION:
Sucrose and milk solids (containing lactose) are major components of many flour mixtures used in the production of cakes, biscuits, breads and confectionary goods. Traditionally these components are measured by titrametric methods1, however, high performance liquid chromatographic methods have also been developed.
Enzymic methods for the measurement of sucrose and lactose are well known, but are not widely used in the cereals industries. With these procedures, sucrose is hydrolysed by invertase to D-glucose and fructose, and lactose is hydrolysed by β-galactosidase to D-glucose plus D-galactose. The D-glucose released from sucrose and lactose, and the free D-glucose in the sample, are determined enzymically [usually with glucose oxidase/peroxidase reagent (GOPOD Reagent)].
KITS:
Kits contain sufficient reagents for performing 100 measurements of D-glucose, sucrose and lactose, i.e. they contain the full assay method plus:
Bottle 1: β-Fructosidase solution (invertase) (yeast; 5 mL) plus sodium benzoate (0.2% w/v) as a preservative.
Stable for > 2 years at 4°C.
Bottle 2: β-Galactosidase (lactase; A. niger, 1 mL) suspension. Stable for > 2 years at 4°C.
Bottle 3: GOPOD Reagent Buffer. Buffer (48 mL, pH 7.4), p-hydroxybenzoic acid and sodium azide (0.4% w/v). Stable for > 4 years at 4°C.
Bottle 4: GOPOD Reagent Enzymes. Glucose oxidase plus peroxidase and 4-aminoantipyrine. Freeze-dried
powder.
Stable for > 5 years at -20°C.
Bottle 5: D-Glucose standard solution (5 mL, 1.0 mg/mL) in 0.2% (w/v) benzoic acid.
Stable for > 5 years at room temperature.
Bottle 6: Control flour sample. Sucrose, lactose and D-glucose contents shown on vial label.
Stable for
> 5 years at room temperature.