柠檬酸检测试剂盒 英文名称: Citric Acid Assay Kit |
型号:null 产品货号: K-CITR |
价格:请致电:010-57128832,18610462672 |
品牌: 爱尔兰 |
品牌: Megazyme 产品货号:K-CITR 品牌:Megazyme 产品品名:柠檬酸检测试剂盒 英文品名:Citric Acid Assay Kit 规格型号:72 assays (manual) / 720 assays (microplate) / 840 assays (auto-analyser) A flexible and simple method for the rapid and reliable measurement ofcitric acid (citrate) in foods, beverages and other materials. INTRODUCTION: Due to its excellent acidulant, flavorant and preservative properties, citric acid (citrate) is found in a large number of natural and processed foods and beverages, such as fruit juice and other soft drinks, beer, milk, bread, candies, and dairy and meat products. This acid also finds many other applications, such as in paper manufacture, or in the wine industry, where the presence of significant quantities indicates the use of citric acid as an acidulant, a practice with an allowable upper limit of just 1 g/L (final concentration) in the EU. The quantification of citric acid is also important in clinical chemistry. Polyvinylpyrollidone (PVP) has been incorporated into the Megazyme assay format to prevent inhibition caused by tannins found in grape juice, fermenting must and wine. In addition to a > 2 years shelf life and competitive price, manual (see page 5 “A”), auto-analyser (see page 6 “B”) and microplate (see page 8 “C”) assay procedures are described, making this product ideal for citric acid determination applications in laboratories of any size. KITS: Kits suitable for performing 72 assays in manual format (or 840 assays in auto-analyser format or 720 assays in microplate format) are available from Megazyme. The kits contain the full assay method plus: Bottle 1: Buffer (40 mL, pH 7.5) plus sodium azide (0.02%) as a preservative. Stable for > 2 years at 4°C. Bottle 2: NADH plus PVP. Stable for > 5 years at -20°C. Bottle 3: L-Malate dehydrogenase plus D-lactate dehydrogenase, 1.5 mL. Stable for > 2 years at 4°C. Bottle 4: (x 3) Citrate lyase lyophilisate. Stable for > 2 years at -20°C. to be performed at the same pH (pH 5.0) which, in turn, simplifies the assay and minimises the possibility of production of maltulose (4-α-glucopyranosyl-D-fructose)11, which is resistant to hydrolysis by amyloglucosidase and α-amylase. The Megazyme total starch analysis procedure allows the measurement of total starch in a wide range of food, feed, plant and cereal products (natural or processed). For most samples (e.g. wheat flour), starch is completely solubilized on incubating the sample at approx. 100°C in the presence of thermostable α-amylase. Samples containing high levels of resistant starch (e.g. high amylose maize starch), require pre-dissolution in cold 2 M KOH or hot DMSO. For samples containing soluble starch or maltodextrins, cooking with thermostable α-amylase is not required. KITS: Kits suitable for performing 100 determinations of total starch are available from Megazyme. The kits contain the full assay method plus: Bottle 1: Thermostable α-amylase (10 mL, 3,000 U/mL on Ceralpha reagent* at pH 6.5 and 40°C or 1600 U/mL on Ceralpha reagent at pH 5.0 and 40°C). Stable for > 4 years at 4°C. Bottle 2: Amyloglucosidase (10 mL, 3300 U/mL on soluble starch (or 200 U/mL on p-nitrophenyl β-maltoside*) at pH 4.5 and 40°C. Stable for > 4 years at 4°C. *Full assay procedure is available at “www.megazyme.com”. 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 > 4 years at room temperature. Bottle 6: Standardised regular maize starch control. Starch content shown on vial label. Stable for > 4 years at room temperature. 温馨提示:需要详细的产品使用说明书,请联系甄准生物客服人员,我们将竭诚为您服务。 甄准,甄心倾听您每一个标准! |