Determination of Starch

The NMKL (1997c) described an enzymatic method for determination of starch and glucose in foods that was validated in a collaborative study. Starch was... 

Method 7.12a. Determination of starch in potatoes by hydroiysis and autoanaiysis... 

Tsiapouris, A., Dresden, L. L. (2000). Water vapor sorption determination of starch based porous packaging materials. Starch, 52, 53-57. 

An effort to reduce the analytical time for enzymatic determination of starch. 

Some important technical details for the enzymatic determination of starch in cereal flours. 

Detection and Determination of Starch.—(a) Qualitative test. A freshly-cut surface of the sample is treated with a few drops of iodine solution to see if a blue coloration is formed. If the result of this test is doubtful, a quantity of the dry, defatted substance is triturated well with a little water, and after depositing for a short time, the turbid liquid examined under the microscope. A little iodine solution is then added and the sped-men again examined microscopically for stained starch granules. 

In the polarimetnc determination of starch, sulphuric acid may be used for the saccharification as described by Miller.2... 

In most cases the determination of starch is not of great importance in the analysis of flour. Besides in the complete analysis of flour, it may be useful in the analysis of brans, in order to indicate if the whole or only part of the flour has been removed. 

Viles, F. J., Jr., and Silverman, L. (1949). Determination of starch and cellulose with anthrone. 

James, M. G., Robertson, D. S and Meyers, A. M. 1995. Characterization of the maize gene sugary 1, a determinant of starch composition in kernels. Plant Cell 7,417-429. 

One other FI-robotic approach clearly exemplifying the advantages of the joint use of both techniques is that to the determination of starch in foods [8]. The sequence of... 

Fig. 10.7. Flow-chart of the robotic steps and flow-injection determination of starch in foods. (Reproduced with permission of Elsevier Science.)...

Fig. 10.8. Robotics-Fl approach to the determination of starch in foodstuff. (--------) Passive interface. (---) Active interfaces. PEC power and event controller, AP all-purpose hand, SH syringe...

Specific Determination of Starch When in the Presence of Other Carbohydrates, Using the Giucoamyiase/Giucose Oxidase Method... 

Mujica, A., and Jacobsen, S. (2006). La quinua (Chenopodium quinoa Willd.) y sus parientes silvestres. Botanica Economica de los Andes Centrales. (M. Mundigler, N. (1998). Isolation and Determination of Starch from Amaranth (Amaranthus cruentus) and Quinoa (Chenopodium quinoa). Starch/Stdrke 50, 2-3, pp. 67-69. 

Mundigler, N. (1998). Isolation and determination of starch from amaranth (Amaranthus cruentus) and quinoa (Chenopodium quinoa). Starch/Stdrke, 50(2-3), 67-69. 

A. Caballo-Lopez, M.D. Luque de Castro, Fast microwave-assisted free sugars washing and hydrolysis pre-treatment for the flow injection determination of starch in food, Talanta 59 (2003) 837. 

Determination of starch in a flow injection system using immobilized enzymes and a modifled electrode Anal. Chim. Acta 180 3-8... 

For determination of starch concentration, starch was first hydrolyzed with glueoamylase to glucose. Glucoamylase from Aspergillus niger (6,100 U/mL, Sigma) was used for measurement of starch concentration after diluted 100 times with distilled water. Culture broth of 0.1 mL and 0.8 mL Dl water were preincubated at 30 °C for 5 min before adding... 

Determination of Starch, Soluble Sugars and Protein Contents of Wheat Brans... 

J. Emn6us, R. Appelqvist, G. Marko-Varga, L. Gorton, and G. Johansson, Determination of Starch in a Flow Injection System Using Immobilized Enzymes and a Modified Electrode. Anal. Chim. Acta, 180 (1986) 3. 

The extent to which the hydrolysis will approach completion is a function of the proportion of carbohydrate to water. Starting with a starch slurry of about 40 per cent dry substance, the reaction will go roughly 80 per cent to completion. If the starch concentration is reduced to approximately 20 per cent, the reaction appears to go about 87 per cent to completion. If the concentration is reduced to 1 per cent, which is in the range of the analytical method for determination of starch substance, the reaction goes about 99 per cent to completion. Even at a concentration of 0.25 per cent, there is still some polymeric material present. Under conditions of moderate concentration in the 50-80 per cent range, the unhydrolyzed polymers consist chiefly, of randomly linked disaccharides, apparently with isomaltose, the alpha-linked 1,6 disaccharide, predominating. 

Fig.4. (top) Reaction scheme for the enzymatic determination of starch as executed in the FIA manifold shown below, where AMG refers to amyloglucosidase and GDH to glucose dehdrogenase, both of which enzymes are immobilized on porous glass in separate packed-bed reactors. The detection of the generated NADH is facilitated amperometrically by means of a modified electrode at 0 mV vs. Ag/AgCl, 0.1 M KCl. Flow rates are given in ml/min injected volume 30... 

The determination of starch purity, for certain economic reasons, became an important point of discussion in Europe. Whatever the source, starch... 

Starch The determination of starch in fruits and fruit juices is normally achieved by the hydrolysis of the starch to glucose and the subsequent analysis of glucose levels. Acid hydrolysis methods can be... 

Velasco-Arjona A and Luque de Castro MD (1996) A robotic flow injection approach to the fully automated determination of starch in Fdo. Analytica Chimica Acta 333 205-213. 

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