According to AOCS CD 8b (Peroxide Value Acetic Acid-Isooctane Method); ISO (Animal and vegetable fats and oils. SAMPLING AND ANALYSIS OF COMMERCIAL FATS AND OILS AOCS Official Method Cd 8b Revised Peroxide Value Acetic. AOCS has standardized a method for. PV determination with chloroform (Cd. 8- 53) and with isooctane (Cd 8b). The latter method uses a mixture of acetic.
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If a blue color is formed that requires more than 1 drop of 0. We need your help! Acetic acid in the pure state is moderately toxic by ingestion and inhalation. Analysts may use 0.
If the titration is less than 0. If stored under refrigeration, the starch solution should be stable for about 2—3 weeks.
Test the saturated KI solution by adding 2 drops of starch solution to 0. Growing consumer awareness has led to more interest in natural cold-pressed plant oils, which are often considered functional foods.
Starch indicator solution—tested for sensitivity, prepared aics making a paste with 1 g of starch see Notes, 2 and a small amount of cold distilled water.
A fume hood should be used at all times when using chloroform. Oil and Soap 9: Isooctane has been cdd as a replacement for chloroform in this method. Low actinic red or amber container, about 50 mL to mL capacity.
Repeatability—The difference between two test results on the same material, in the same laboratory under the same conditions, should not exceed the repeatability value, r.
Add, while stirring, to mL of boiling water and boil for a few seconds. Continue the titration until the yellow iodine color has almost disappeared. A properly operating fume hood should be used when working with cf solvent. The test should be carried out in diffuse b8 or in artificial light shielded from a direct light source. It is a strong oxidizing agent and a dangerous fire risk when in Table 2 The results of international collaborative tests held between and see References, 5.
Store in the dark when not in use. The strength of the sodium thiosulfate solution is expressed in terms of its normality. This solution may be prepared by accurately pipetting mL of 0. Allow to stand for 5 min and then add mL of distilled water. Dissolve in 25 mL of water, add 5 mL of concentrated hydrochloric aocss, 20 mL of potassium iodide solution Reagents, 2 and rotate aics mix.
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Please fill this form, we will try to respond as soon as possible. The International Standards Organization ISO successfully completed an international collaborative study cf this method in Fresh indicator must be prepared when the end point of the titration from blue to colorless fails to be sharp. We need your help to maintenance this website.
Size px x x x x KI in mL water and rotate to mix. Decant the oil into a clean beaker and filter through aoca Whatman no. It is toxic by inhalation and has anesthetic properties.
AOCS CD 8b – 90 Peroxido
The aim of this study was aods compare the nutritional value and quality of sixteen unconventional cold-pressed edible oils.
If the titration is less than 0. This method is highly empirical, and any variation in the test procedure may result in erratic results. Burette—25 mL or 50 mL, class A, graduated in 0. Based on collaborative study results References, 1,2the recommendation is to use 0. Add the thiosulfate solution dropwise until the blue color just disappears see Notes, 4.
Weigh the test portion Table 1 into a mL Erlenmeyer flask with glass stopper and add 50 wocs of the 3: When completely melted, remove the sample from the hot plate or oven and allow to settle in a warm place until the aqueous portion and aosc of the milk solids have settled to the bottom. Allow the solution to stand with occasional shaking for exactly 1 min, and then c add 30 mL of distilled water see Notes, 3 and References, 1. Starch indicator solution—tested for sensitivity, prepared by making a paste with 1 g of starch see Notes, 1 and a small amount of cold distilled water.
It is a strong irritant to skin and tissue.