ESTIMATION OF THE SUITABILITY OF METHODS FOR DETERMINING LACTIC ACID CONTENT IN DIFFUSION JUICE FOR APPLICATION IN CHEMICAL AND TECHNICAL CONTROL OF SUGAR PRODUCTION

2020 ◽  
Vol 13 (4(50)) ◽  
pp. 89-94
Author(s):  
O. V. Koloskova ◽  
O. K. Nikulina ◽  
M. R. Yakovleva
Keyword(s):  
Lactic Acid ◽  
Spectrophotometric Method ◽  
Production Control ◽  
Sugar Industry ◽  
Operational Control ◽  
Microbiological Contamination ◽  
Factors Affecting ◽  
Spectrophotometric Methods ◽  
Technical Control ◽  
Microbiological Infection

Development of microbiological infection in the process of production of diffusion juice is one of the most important factors affecting the quality of diffusion juice and sucrose loss. In this regard, it is important to promptly monitor the microbiological contamination of mixture from water and beet chips in the diffusion apparatus. Lactic acid is used as an indicator of the degree of microbiological contamination of the diffusion juice. Traditionally, when calculating unaccounted sucrose losses on diffusion, the titrimetric method is used to determine the concentration of lactic acid with preliminary isolation of acid anions from the diffusion juice on ionite columns. However, this method is time-consuming and labor-intensive and is not suiTable for operational control. The article suggests using a simpler and less time-consuming spectrophotometric method for operational control, based on measuring the optical density of the colored product of the reaction of lactate ions with iron(III) chloride at a wavelength 400 nm. The results of evaluating the consistency of data on the content of lactic acid in diffusion juices obtained using the traditional and spectrophotometric methods are presented in article. The results of data analysis using the Bland-Altman descriptive statistics method confirm that the data obtained by various methods are in good agreement with each other, and therefore the spectrophotometric method for determining the concentration of lactate ions can be used in production control in the sugar industry.

Factors affecting the ability of dental cements to alter the pH of lactic acid solutions

2000 ◽  
Vol 27 (12) ◽  
pp. 1030-1033 ◽  
Author(s):  
M. Patel ◽  
H. Tawfik ◽  
Y. Myint ◽  
D. Brocklehurst ◽  
J. W. Nicholson
Keyword(s):  
Lactic Acid ◽  
Acid Solutions ◽  
Factors Affecting

Using Indicator Bacteria and Salmonella Test Results from Three Large-Scale Beef Abattoirs over an 18-Month Period To Evaluate Intervention System Efficacy and Plan Carcass Testing for Salmonella

2007 ◽  
Vol 70 (12) ◽  
pp. 2732-2740 ◽  
Author(s):  
JOHN R. RUBY ◽  
JUN ZHU ◽  
STEVEN C. INGHAM
Keyword(s):  
Lactic Acid ◽  
Large Scale ◽  
Microbial Contamination ◽  
Test Results ◽  
Microbiological Contamination ◽  
Negative Results ◽  
Intervention Process ◽  
Beef Carcasses ◽  
Causative Factors ◽  
Plate Counts

To develop a process for predicting the likelihood of Salmonella contamination on beef carcasses, we evaluated the influence of several possible causative factors (i.e., year, abattoir, day of week, month, and intervention system components) on the risk of Salmonella and indicator organism contamination. Hide and carcass sponge samples were collected in 2005 to 2006 in six steps at three abattoirs in the East (A), Midwest (B), and Southwest (C) United States. Each abattoir used the same intervention system. Samples were analyzed for aerobic plate counts (APCs; n = 18,990) and Enterobacteriaceae counts (EBCs; n = 18,989) and the presence or absence of Salmonella (n = 5,355). Our results demonstrated that many factors play a significant role in the level of microbial contamination of beef carcasses. Overall, Salmonella prevalence and EBC levels were significantly higher in 2006 than in 2005. APCs and EBCs were highest in abattoirs A (3.57 log CFU/100 cm2) and B (1.31 log CFU/100 cm2). The odds of detecting a positive Salmonella isolate were greatest in abattoir C and lowest in abattoir A. Across the three abattoirs, the overall intervention process effectively reduced microbiological contamination. Salmonella prevalence fell from 45% (preevisceration) to 0.47% (postchilled–lactic acid), and there were APC and EBC reductions of 5.43 and 5.28 log CFU/100 cm2, respectively, from hide-on to postchilled–lactic acid samples. At each abattoir, composites of three individual EBC-negative carcass samples yielded Salmonella-negative results 97 to 99% of the time. These results suggest the possibility of using indicator test results to accurately predict the absence of Salmonella in a beef carcass sample.

Factors Affecting Aflatoxin B1 Removal by Flavobacterium aurantiacum

1995 ◽  
Vol 58 (1) ◽  
pp. 91-94 ◽  
Author(s):  
J. E. LINE ◽  
R. E. BRACKETT
Keyword(s):  
High Performance Liquid Chromatography ◽  
Liquid Chromatography ◽  
Aflatoxin B1 ◽  
Spectrophotometric Method ◽  
Phosphate Buffer ◽  
High Performance ◽  
Hplc Method ◽  
Apparent Effect ◽  
Factors Affecting ◽  
Aflatoxin Concentration

This study was conducted to investigate several factors affecting the removal of aflatoxin B1 by Flavobacterium aurantiacum NRRL B-184. A simple spectrophotometric procedure was evaluated and compared to an established high-performance liquid chromatography (HPLC) method and found to be useful for determining aflatoxin concentration in test solutions of phosphate buffer. Using the spectrophotometric method, 72-h cultures of F. aurantiacum were observed to remove more toxin from solution than 24-h cultures. Likewise, populations of 1010cells removed aflatoxin at a faster rate than did 109 cells, although the total amount removed did not differ. Transferring F. aurantiacum cultures in tryptic soy broth every 3 days for over 3 days for over 8 months had no apparent effect on their ability to remove measurable amounts of aflatoxin B1 from solution. Populations of 1 × 109 CFU/ml or less heat-inactivated F. aurantiacum were unable to remove aflatoxin B1 from phosphate buffer.

Determination of soluble carbohydrates, lactic acid and volatile fatty acids in soils and biological media

1929 ◽  
Vol 19 (4) ◽  
pp. 649-655 ◽  
Author(s):  
V. Subrahmanyan
Keyword(s):  
Fatty Acids ◽  
Lactic Acid ◽  
Volatile Fatty Acids ◽  
Soluble Carbohydrates ◽  
Biological Media ◽  
Factors Affecting

Methods for extraction, concentration and determination of minute quantities of soluble carbohydrates, lactic acid and volatile fatty acids have been described. Different factors affecting the accuracy of the determinations have been studied and corrections, where necessary, have been suggested.

A Continuous Spectrophotometric Method for Measuring the Activity of Serum Alkaline Phosphatase

1966 ◽  
Vol 12 (2) ◽  
pp. 70-89 ◽  
Author(s):  
George N Bowers ◽  
Robert B McComb
Keyword(s):  
Alkaline Phosphatase ◽  
Standard Deviation ◽  
Sample Size ◽  
Spectrophotometric Method ◽  
Serum Alkaline Phosphatase ◽  
Serum Alkaline Phosphatase Activity ◽  
Factors Affecting ◽  
Nitrophenyl Phosphate ◽  
Relative Standard ◽  
Hydrolysis Of

Abstract A continuous spectrophotometric method for measuring serum alkaline phosphatase activity is described. The effects of temperature, pH, substrate concentration, type and molarity of the buffer, sample size, cofactors, and inhibitors on the enzymatic hydrolysis of p-nitrophenyl phosphate were studied. The optimal conditions for assay of serum alkaline phosphatase at 30° were found to be 0.75 M 2-amino-2-methyl-1-propanol buffer, pH30° 10.15, 4 mmole substrate, and 100 µl. or less sample size. Studies of the factors affecting analytical precision-i.e., control of reaction temperature, of reagent manufacture, and of standardization-are discussed. The precision of this method was 2.3% (relative standard deviation) on 10 within day replicates and 5.0% on day-to-day replicates spread over a 5-week period. The range of activity for 258 apparently healthy adult blood donors was 6-110 mU./ml. (International milliunits per milliliter), with a mean of 49 and a standard deviation of 14.

scholarly journals Factors Affecting the Adoption of Value-added Production on Cow-Calf Farms

1999 ◽  
Vol 31 (1) ◽  
pp. 97-108 ◽  
Author(s):  
Michael P. Popp ◽  
Merle D. Faminow ◽  
Lucas D. Parsch
Keyword(s):  
Human Capital ◽  
Production Control ◽  
Value Added ◽  
Farm Size ◽  
Farm Labor ◽  
Cattle Production ◽  
Land Quality ◽  
Minimal Impact ◽  
Factors Affecting ◽  
Cow Calf

AbstractFactors that affect the decision to feed or sell calves at weaning are analyzed for Arkansas cow-calf operators. A discrete choice logit model is used to analyze the adoption of value-added cattle production. Farm size, human capital, perception of risk/returns and enterprise diversification are hypothesized to explain this decision. Regional factors and land quality are also accounted for. Operator perceptions towards risk, profitability and facilities were important. Production control and attention to marketing were also significant, but farm size and scale of cattle production had a minimal impact. Effects of human capital and off-farm labor opportunities need further investigation.

scholarly journals A rapid spectrophotometric determination of imidacloprid in selected commercial formulations in the presence of 6-chloronicotinic acid

2009 ◽  
Vol 74 (12) ◽  
pp. 1455-1465 ◽  
Author(s):  
Valéria Guzsvány ◽  
Zsigmond Papp ◽  
Sanja Lazic ◽  
Ferenc Gaál ◽  
Luka Bjelica ◽  
...  
Keyword(s):  
Spectrophotometric Method ◽  
High Performance ◽  
High Performance Liquid Chromatographic ◽  
Model Systems ◽  
Zero Crossing ◽  
Spectrophotometric Methods ◽  
Liquid Chromatographic Method ◽  
Relative Standard ◽  
Liquid Chromatographic

A simple first-order derivative spectrophotometric method was developed for the simultaneous determination of imidacloprid and 6-chloronicotinic acid (6-CNA). By using the zero-crossing approach, imidacloprid was determined at 249 nm and 6-CNA at 236 nm with detection limits of 0.32 and 0.17 ?g mL-1, respectively, and relative standard deviations not exceeding 1.2 % in the case of model systems. The proposed method was applied for the determination of imidacloprid and 6-CNA in commercial formulations. A conventional spectrophotometric method (at 270 nm) was also employed for the determination of the content of imidacloprid in the same commercial formulations. The results of the developed spectrophotometric methods were in good agreement with those obtained by the high-performance liquid chromatographic method.

scholarly journals Development and Validation of Spectrophotometric Methods for Determination of Fluoxetine, Sertraline, and Paroxetine in Pharmaceutical Dosage Forms

2005 ◽  
Vol 88 (1) ◽  
pp. 38-45 ◽  
Author(s):  
Ibrahim A Darwish
Keyword(s):  
Correlation Coefficients ◽  
Dosage Forms ◽  
Pharmaceutical Dosage Forms ◽  
Factors Affecting ◽  
Spectrophotometric Methods ◽  
Linear Relationships ◽  
Relative Standard ◽  
Optimum Reaction ◽  
Standard Deviations

Abstract Three simple and sensitive spectrophotometric methods were developed and validated for determination of the hydrochloride salts of fluoxetine, sertraline, and paroxetine in their pharmaceutical dosage forms. These methods were based on the reaction of the N-alkylvinylamine formed from the interaction of the free secondary amino group in the investigated drugs and acetaldehyde with each of 3 haloquinones, i.e., chloranil, bromanil, and 2,3-dichloronaphthoquinone, to give colored vinylamino-substituted quinones. The colored products obtained with chloranil, bromanil, and 2,3-dichloronaphthoquinone exhibit absorption maxima at 665, 655, and 580 nm, respectively. The factors affecting the reactions were studied and optimized. Under the optimum reaction conditions, linear relationships with good correlation coefficients (0.9986–0.9999) were found between the absorbances and the concentrations of the investigated drugs in the range of 4–120 μg/mL. The limits of detection for the assays ranged from 1.19 to 2.98 μg/mL. The precision values of the methods were satisfactory; the relative standard deviations were 0.56–1.24%. The proposed methods were successfully applied to the determination of the 3 drugs in pure and pharmaceutical dosage forms with good accuracy; the recoveries ranged from 99.1 to 101.3% with standard deviations of 1.15–1.92%. The results compared favorably with those of reported methods.

Effect of Laser Surface Modification on the Crystallinity of Poly(L-Lactic Acid)

2009 ◽  
Vol 131 (5) ◽  
Author(s):  
Anubha Bhatla ◽  
Y. Lawrence Yao
Keyword(s):  
Lactic Acid ◽  
Polymer Surface ◽  
X Ray Diffraction ◽  
Factors Affecting ◽  
Laser Surface Modification ◽  
Third Harmonic ◽  
X Ray ◽  
Annealing Conditions ◽  
Kinetics Of

Crystallinity of semicrystalline polymers such as aliphatic homopolymer poly(L-lactic acid) (PLLA) affects their degradation and physical properties. In this paper, the effects of laser irradiation using the third harmonic of a Nd:YAG laser on the crystallinity, long-range order, and short-range conformations at the surface of PLLA films are investigated. The factors affecting the transformation are also studied. Detailed characterization of the effect of laser treatment is accomplished using microscopy, X-ray diffraction, and infrared spectroscopy. The cooling rates in the process and the spatial and temporal temperature profiles are numerically examined. The simulation results in conjunction with melting and crystallization kinetics of PLLA are used to understand the effect on sample crystallinity. The effects of laser fluence and annealing conditions on the crystallinity of the processed films are examined. Since degradation profiles depend on crystallinity, laser processing can potentially be used to achieve a modified spatially controlled polymer surface with promising applications such as controlled drug delivery.

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