scholarly journals Improved Protocol for an Oxygen Electrode Method for Determining Hydrogen Peroxide in Foods

1997 ◽  
Vol 80 (3) ◽  
pp. 681-687 ◽  
Author(s):  
Fumio Miyamoto ◽  
Masanobu Saeki ◽  
Takumi Yoshizawa
Keyword(s):  
Hydrogen Peroxide ◽  
Standard Method ◽  
Present Method ◽  
Accurate Determination ◽  
Oxygen Electrode ◽  
Nitrogen Gas ◽  
Naturally Occurring ◽  
Residual Hydrogen ◽  
Electrode Method

Abstract An oxygen electrode method for determining residual hydrogen peroxide in foods has been further improved. Pretreatment, which includes extraction and neutralization, is done in a hydrogen peroxide extraction apparatus with nitrogen gas bubbling. The hydrogen peroxide concentration of the sample is corrected by subtracting the sample blank value, obtained for the sample through catalase treatment. Bubbling with nitrogen gas effectively minimized the sample blank value, making this method suitable for accurate determination of trace amounts of hydrogen peroxide in foods. Recoveries of hydrogen peroxide added at 1-10 μg/g were 77.8-107.1% by the present method. These recoveries are similar to or higher than those by the Japanese standard method and by another modified oxygen electrode method. Concentrations of naturally occurring hydrogen peroxide in solid foods were <0.87 μg/g by the present method, lower than those by either the standard method or another modified oxygen electrode method.

scholarly journals Greener Analytical Method for Determination of Iodine Number of Edible Oils

2020 ◽  
Vol 9 (6) ◽  
pp. 36
Author(s):  
Thidarat Kruatian ◽  
Kritsana Jitmanee
Keyword(s):  
Iodine Number ◽  
Standard Method ◽  
Analytical Method ◽  
Present Method ◽  
Edible Oils ◽  
Classical Method ◽  
Sample Weight ◽  
Number Range ◽  
Significant Difference

A greener analytical method for determination of iodine number (IN) of oils is presented. As per the AOAC standard method, a large amount of solvent and reagent was used, and long incubation time was required. This research is aimed at using less amount of solvent and reagent, less sample weight, and shorten the analysis time by using the modified titrimetric AOAC standard method. The study showed that by reducing the sample size, the amount of reagent could be decreased to 1.00 mL and the reaction time of 1 min is enough for completion of the reaction. The amount of reagent used was at least 25 times less than that of the classical method. There was no significant difference at 95% confidence level between the results obtained by the proposed method and the standard method, and both results correlated well. The present method can be applied to edible oils commonly found in the market (iodine number range of 6.0 to 130).

scholarly journals IMPROVED HPLC RESOLUTION AND QUANTIFICATION OF ELLAGIC ACID FROM STRAWBERRY, BLACKBERRY, AND CRANBERRY

HortScience ◽  
1990 ◽  
Vol 25 (9) ◽  
pp. 1078c-1078 ◽  
Author(s):  
S. Y. Wang ◽  
J. L. Maas ◽  
E. M. Daniel ◽  
G. J. Galletta
Keyword(s):  
Ellagic Acid ◽  
Accurate Determination ◽  
Ammonium Phosphate ◽  
Solvent System ◽  
Animal Nutrition ◽  
Genetic Studies ◽  
Naturally Occurring ◽  
Chemically Induced ◽  
Improved Methods

Ellagic acid (EA) a naturally occurring polyphenol in many fruit and nut crops, is a putative inhibitor of certain chemically-induced cancers. Improved methods of extraction, detection and quantification are essential for accurate determination of EA for plant physiological and genetic studies and animal nutrition and chemopreventative studies. Column (C18) preconditioning significantly reduced column retention of EA. An ammonium phosphate/methanol solvent system was used in preference to sodium phosphate/methanol. Fruit sample determinations were 10-100 times higher than previously reported, due to the improvements in efficiency of these methods. EA levels (mg/g dry wt) were: strawberry pulp (1.55), achene (8.46), root (1.55), crown (3.32) and leaf (14.27); blackberry pulp (,2.43) and seed (3.37); and cranberry skin (1.06), pulp (0.31), seed (0.69), leaf (4.10).

THERMAL EXPANSION OF ALKALI HALIDES: A SEMICLASSICAL MODEL

1994 ◽  
Vol 08 (07) ◽  
pp. 425-430 ◽  
Author(s):  
GOUTAM DEV MUKHERJEE ◽  
C. BANSAL ◽  
ASHOK CHATTERJEE
Keyword(s):  
Experimental Data ◽  
Thermal Expansion ◽  
Theoretical Prediction ◽  
Debye Temperature ◽  
Present Method ◽  
Accurate Determination ◽  
Alkali Halides ◽  
Semiclassical Model ◽  
Semiclassical Method

A simple-minded semiclassical method is used to obtain the thermal expansion of alkali halides viz. KBr, KCl, Kl, and NaCl. It is observed that our theoretical prediction agrees fairly well with the available experimental data. It is furthermore suggested that the present method can be used for an accurate determination of the Debye temperature of alkali halides.

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