POLARIMETRIC DETERMINATION OF STARCH IN CEREAL PRODUCTS: I. RAPID DETERMINATION OF STARCH IN CRUDE GLUTEN

1942 ◽  
Vol 20c (8) ◽  
pp. 403-410 ◽  
Author(s):  
K. A. Clendenning
Keyword(s):  
Present Method ◽  
Chloride Solution ◽  
Rapid Determination ◽  
Starch Content ◽  
Calcium Chloride Solution ◽  
Stannic Chloride ◽  
Constant Ratio ◽  
Cereal Products ◽  
Rapid Procedure

Neither the original Mannich–Lenz procedure nor its recently proposed revisions proved suitable for the polarimetric determination of starch in gluten. The principal defect lay in the means of removing or correcting for proteins dissolved along with the starch and there also was a need for improvements in technique of starch dispersion.In the present method, the starch of the gluten sample is dispersed by 15 min. boiling in a calcium chloride solution having a specific gravity of 1.30 and a pH of approximately 2.5. Frothing is controlled by the addition of one or two drops of n-octyl alcohol, constant volume being maintained during boiling by the addition of water. The proteins dissolved by this treatment are precipitated with 20% stannic chloride prior to filtration and polarization. This rapid procedure underestimates the starch content but the application of a factor to correct for the constant ratio of underestimation allows the real starch content to be determined with an accuracy of ±0.5%.

POLARIMETRIC DETERMINATION OF STARCH IN CEREAL PRODUCTS: IV. CRITICAL STUDIES OF METHODS FOR THE DETERMINATION OF STARCH IN WHOLE WHEAT, GRANULAR, AND PATENT FLOURS

1945 ◽  
Vol 23b (6) ◽  
pp. 239-259 ◽  
Author(s):  
K. A. Clendenning
Keyword(s):  
Calcium Chloride ◽  
Chloride Solution ◽  
Specific Rotation ◽  
Large Error ◽  
Uranyl Acetate ◽  
Calcium Chloride Solution ◽  
Stannic Chloride ◽  
Rice Grain ◽  
Whole Wheat

A rapid polarimetric method applicable to whole wheat, granular, and patent flour is described in which the starch is dissolved in hot calcium chloride solution under uniform conditions, soluble proteins being removed by the addition of stannic chloride or uranyl acetate prior to volume adjustment, filtration, and polarization.Approximately 2.5-gm. samples (40 mesh) are placed in tall beakers and suspended uniformly in 10 cc. of water. Calcium chloride solution (60 cc., d. 1.30, pH 5.5) and 2 cc. of 0.8% acetic acid are added. The mixture is boiled at constant salt concentration for 15 min., foaming being prevented by dropwise addition of n-octanol as required. After cooling, 2.5 to 5.0 cc. of 4% stannic chloride or 10 cc. of 5% uranyl acetate (each dissolved in calcium chloride solution) is added, the mixture is diluted to 100 cc. with calcium chloride solution, mixed, and filtered. After discarding the first portion, the filtrate is polarized in 2 dm. tubes. [α]D = + 203° is used in the calculations; % starch = 2 dm. reading in degrees × 10 when 2.463 gm. flour samples are employed.Stannic chloride is shown to depress the specific rotation value of starches. A large error is introduced when it is used on wheat flour in the amount prescribed by Mannich and Lenz. Using the above uranyl acetate treatment, starch may be rapidly determined in corn, barley, rye, rice, grain sorghum, and buckwheat by the calcium chloride polarimetric method. It is shown that interfering wheat proteins may be removed by preparatory extraction with aqueous ethanol and dilute sodium hydroxide, as well as by precipitation. The latter being more rapid is judged most suitable for routine applications. Levorotatory hemicelluloses of bran and endosperm are dissolved in considerable amount by boiling calcium chloride solution but their small effect is balanced by the error of overestimation arising from insoluble wheat solids. Hemicelluloses are shown to be capable of causing high results in applications of the diastase–hydrochloric-acid method to wheat products. The improved calcium chloride polarimetric method is considered the most reliable of existing macro-methods for the determination of starch in wheat.

The Rapid Determination of Calcium in Biologic Material

1959 ◽  
Vol 5 (1) ◽  
pp. 36-44 ◽  
Author(s):  
Harold D Appleton ◽  
Marcia West ◽  
Mary Mandel ◽  
Angelo M Sala
Keyword(s):  
Excellent Agreement ◽  
Rapid Determination ◽  
Rapid Procedure ◽  
End Point ◽  
Titration Procedure ◽  
Serum And Urine

Abstract A rapid procedure for the routine determination of calcium in serum and urine has been described. 0.1 ml. of serum is titrated directly with standard EDTA, using either a calcein-KCl mixture or a calcein-thymolphthalein-KCl mixture. The end point with either indicating mixture is sharp. Excellent agreement is shown with the oxalate isolation and permanganate titration procedure.

Procedure for rapid determination of δ15N and δ18O values of nitrate: development and application to an irrigated rice paddy watershed

2016 ◽  
Vol 73 (9) ◽  
pp. 2108-2118
Author(s):  
Saeko Yada ◽  
Yasuhiro Nakajima ◽  
Sunao Itahashi ◽  
Kei Asada ◽  
Seiko Yoshikawa ◽  
...  
Keyword(s):  
Rapid Determination ◽  
Isotope Ratio Mass Spectrometry ◽  
Rice Paddy ◽  
Irrigated Rice ◽  
Rapid Procedure ◽  
Dual Isotope ◽  
History Of ◽  
Pre Treatment ◽  
Current Sample

The dual isotope approach using the stable isotope ratios of nitrate nitrogen (δ15NNO3) and oxygen (δ18ONO3) is a strong tool for identifying the history of nitrate in various environments. Basically, a rapid procedure for determining δ15NNO3 and δ18ONO3 values is required to analyze many more samples quickly and thus save on the operational costs of isotope-ratio mass spectrometry (IRMS). We developed a new rapid procedure to save time by pre-treating consecutive samples of nitrous oxide microbially converted from nitrate before IRMS determination. By controlling two six-port valves of the pre-treatment system separately, IRMS determination of the current sample and backflush during the next sample pre-treatment period could be conducted simultaneously. A set of 89 samples was analyzed precisely during a 25-h continuous run (17 min per sample), giving the fastest reported processing time, and simultaneously reducing liquid nitrogen and carrier helium gas consumption by 35%. Application of the procedure to an irrigated rice paddy watershed suggested that nitrate concentrations in river waters decreased in a downstream direction, mainly because of the mixing of nitrate from different sources, without distinct evidence of denitrification. Our procedure should help with more detailed studies of nitrate formation processes in watersheds.

scholarly journals Simplified two-step column-chromatographic determination of taurine in urine.

1978 ◽  
Vol 24 (2) ◽  
pp. 321-325 ◽  
Author(s):  
M A Anzano ◽  
J O Naewbanij ◽  
A J Lamb
Keyword(s):  
Present Method ◽  
Exchange Resin ◽  
Rapid Determination ◽  
Cation Exchange Resin ◽  
Chromatographic Determination ◽  
Cysteic Acid ◽  
Chromatographic Procedure ◽  
Acidic Compounds ◽  
Column Chromatographic

Abstract A two-step column-chromatographic procedure for accurate and rapid determination of taurine in urine is described. Sulfosalicyclic-acid deproteinized samples are chromatographed on a 0.9 X 10 cm column of cation-exchange resin (AG 50W-XB), with use of a pH 2.2 sodium citrate eluting buffer such that taurine and the more highly acidic compounds in urine are eluted in the void volume, and then on a 0.9 X 8 cm column of anion-exchange resin (AG 2-X8), from which taurine is preferentially eluted with 1 mol/liter acetic acid. The color developed with ninhydrin is directly proportional to taurine amounts as low as 0.01 mumol/sample. The method is highly reproducible, with analytical recoveries greater than 95%. The presence of 333 mumol of urea and 1 mumol of cysteic acid did not interfere in the analysis. When a mixture of C14-labeled amino acids other than taurine were co-chromatographed with taurine, less than 2% of the total counts loaded were located in the taurine fraction. Values for urinary taurine excretion by rats according to the present method agreed well with values obtained with an automated amino acid analyzer. Advantages of the present method for the determination of taurine are discussed.

Determination of the orientation of internal linear defects in isotropic optical crystals

2019 ◽  
Vol 85 (2) ◽  
pp. 29-32
Author(s):  
V. N. Cheredov ◽  
A. E. Petrakov
Keyword(s):  
Crystallographic Orientation ◽  
Material Science ◽  
Rapid Determination ◽  
Optical Microscope ◽  
Rapid Procedure ◽  
Linear Defects ◽  
Method Of Determination ◽  
Optical Crystals ◽  
The Given

Study of the structure of optical crystals and defects in them is one of the most important problems in crystal physics, crystallography and material science. Nowadays, study of the nanostructures, including the linear defects in crystals is of particular importance. Defects, and first and foremost linear imperfections of the crystal structure, significantly reduce the operational physical properties of optical crystals. Analysis of the properties of those defects, their orientation in the crystal lattice, as well as developing of the methods for determination of the crystallographic orientation of linear defects are the most important in view of the possibility of improving the properties of optical crystals. A method for rapid determination of the crystallographic orientation of linear defects (dislocations, clusters, linearly extended bulk inclusions, etc.) in optical crystals is presented. The orientation of a linearly extended micropore in an isotropic optical transparent fluorite crystal was determined using an optical microscope. The readings of the scale of the eyepiece drum were recorded when rotating the crystal fixed in the crystal holder of the microscope. Corrections for the refraction of light in the bulk of the crystal were taken into account analytically. The crystallographic orientation of the microporous in a transparent fluorite crystal was studied in detail. Crystallographic indices of micropore orientation corresponded to [100]. We developed an efficient rapid procedure for determination of the orientation of internal linear defects (imperfections) in optically isotropic crystals using an optical microscope. The restrictions imposed on the angles of crystal rotation depending on the value of the refractive index are considered for the given method of determination.

Rapid determination of ochratoxin A in cereals and cereal products by liquid chromatography

2004 ◽  
Vol 1046 (1-2) ◽  
pp. 127-131 ◽  
Author(s):  
J. Blesa ◽  
H. Berrada ◽  
J.M. Soriano ◽  
J.C. Moltó ◽  
J. Mañes
Keyword(s):  
Liquid Chromatography ◽  
Ochratoxin A ◽  
Rapid Determination ◽  
Cereal Products

Rapid determination of ochratoxin A in cereals and cereal products by liquid chromatography☆

2004 ◽  
Vol 1046 (1-2) ◽  
pp. 127-131
Author(s):  
J BLESA ◽  
H BERRADA ◽  
J SORIANO ◽  
J MOLTO ◽  
J MANES
Keyword(s):  
Liquid Chromatography ◽  
Ochratoxin A ◽  
Rapid Determination ◽  
Cereal Products

scholarly journals UV SPECTROPHOTOMETRY METHOD DEVELOPMENT AND VALIDATION OF SULFADIAZINE AND TRIMETHOPRIM IN COMBINED DOSAGE FORM

2018 ◽  
Vol 10 (1) ◽  
pp. 103
Author(s):  
Ramakrishna Veni Pokala ◽  
Kusuma Kumari ◽  
Hari Babu Bollikola
Keyword(s):  
Present Method ◽  
Method Development ◽  
Rapid Determination ◽  
Uv Spectrophotometry ◽  
Control Analysis ◽  
Quality Control Analysis ◽  
Double Beam ◽  
Method Development And Validation ◽  
Development And Validation

Objective: A new, simple, sensitive and economical UV spectrophotometric method was developed for the simultaneous analysis of Sulfadiazine [SDA] and Trimethoprim [TMP] in pharmaceutical formulations.Methods: This UV method was developed with methanol as solvent. The wavelengths selected for analysis in the present method were 265 nm for TMP and 289 nm for SDA. Teccomp UV-2301 double beam UV/Vis spectrophotometer was used to carry out spectral analysis and the data was recorded by Hitachi software.Results: Linearity was found to be within the concentration range of 2-9 µg/ml TMP and 9.08-41 µg/ml of SDA. Accuracy of the method was determined by recovery studies. Percentage recovery was found to be 98.20-99.25 for TMP with a % RSD of 0.338, 0.506 and 0.510 for three spiked levels. % RSD was found to be 0.229 and 0.380; 0.212 and 0.328 for SDA, TMP in intra and inter-day precision respectively. The % RSD value in ruggedness was found to be 0.440 for SDA and 0.569 for TMP.Conclusion: The advantages of this method for analytical purposes lie in the rapid determination, its cost-effectiveness, easy preparation of the sample, good reproducibility. In addition to this, the present method can be recommended for simultaneous determination of SDA and TMP in routine quality control analysis in combined drug formulations.

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