Improved Method for Extraction of Filth from Cheese

1986 ◽  
Vol 69 (4) ◽  
pp. 712-713
Author(s):  
Mary-Ann Gardiner ◽  
Diane McClymont Peace
Keyword(s):  
Microscopic Examination ◽  
Lower Cost ◽  
Official Method ◽  
Improved Method ◽  
Soft Cheese ◽  
Aoac Method ◽  
Wet Sieving

Abstract An official AOAC method for detection of total filth in hard and soft cheese was modified to (a) achieve digestion of cheese at lower cost, (b) improve filtration rates, and (c) facilitate microscopic examination of the filth collected. The modifications involve a wet-sieving step, a reduction in the amounts of liquid filtered and pancreatin used, a detergent defatting step, and an acid boil step, if required. Average recoveries ranged from 85 to 100%. The method modifications should be collaboratively studied so changes in the official method can be recommended

Collaborative Study of an Improved Method for the Isolation of Filth from Starches

1972 ◽  
Vol 55 (1) ◽  
pp. 62-63
Author(s):  
John S Gecan ◽  
Paris M Brickey
Keyword(s):  
Acid Hydrolysis ◽  
Collaborative Study ◽  
Official Method ◽  
Improved Method ◽  
Modified Method ◽  
Aoac Method ◽  
Wet Sieving

Abstract The official AOAC method for filth in starches, 40.056, has been modified to obtain better recovery of extraneous materials. In lieu of wet sieving on a No. 140 sieve, the modified method utilizes No. 230 wet sieving followed by an acid hydrolysis, if excessive starch material remains on the sieve. A limited collaborative study comparing the improved method with the official method resulted in higher recoveries of rodent hairs and equivalent recoveries of other spike elements by the improved method. The improved method is recommended for adoption as official first action to replace 40.056.

Extraction of Light Filth from Tea: Collaborative Study

1981 ◽  
Vol 64 (2) ◽  
pp. 287-290
Author(s):  
Faith F Lim ◽  
◽  
J Barnett ◽  
A Bright ◽  
M P Chaput ◽  
...  
Keyword(s):  
Sample Preparation ◽  
Collaborative Study ◽  
Tween 80 ◽  
Mineral Oil ◽  
Plant Residue ◽  
Official Method ◽  
Existing Problems ◽  
Aoac Method ◽  
Filter Papers ◽  
Wet Sieving

Abstract The present AOAC method for determining insect and rodent filth in tea is time-consuming because it produces filter papers which are heavy in plant residue and therefore requires long paper-reading times. Anew method for the analysis of light filth in tea was developed to remedy existing problems and to improve recoveries. The method consists of the following steps: sample preparation, wet sieving, dilution with 40% isopropanol, extraction with Tween 80-Na4EDTA-40% isopropanol, flotation with mineral oil-heptane, and trapping off in a Wildman trap flask. In an interlaboratory collaborative study, analysts reported combined insect fragment recoveries of 99.2% for the proposed method and 93.0% for the AOAC method; the same analysts recorded combined rodent hair recoveries of 92.2% for the proposed method and 47.6% for the official method. Average times for reading individual subsamples were 9 min for the proposed method and 27 min for the AOAC method. The proposed method has been adopted official first action.

Collaborative Study of the Extraction of Light Filth from Canned Whole and Cream Style Corn

1973 ◽  
Vol 56 (3) ◽  
pp. 634-636
Author(s):  
Russell G Dent
Keyword(s):  
Microscopic Examination ◽  
Castor Oil ◽  
Collaborative Study ◽  
Official Method ◽  
Improved Method ◽  
Paraffin Oil ◽  
Macroscopic Examination

Abstract An improved method has been developed for canned whole and cream style corn to replace 40.104. The proposed method is unique because the microscopic and macroscopic examinations can be conducted almost concurrently; in the official method the macroscopic examination is dependent upon completion of the microscopic examination. The proposed method is shorter and it eliminates the use of viscous castor oil by specifying extraction in a percolator with paraffin oil from hot 40% isopropanol. Glassware is easily cleaned up after percolator cycles with isopropanol and water rinses. The proposed method yielded improved recoveries of insect and rodent filth spike elements. The method has been adopted as official first action.

Extraction of Light Filth from Ground Allspice: Collaborative Study

1980 ◽  
Vol 63 (6) ◽  
pp. 1266-1268
Author(s):  
Russell G Dent ◽  
◽  
J G Eye ◽  
C C Freeman ◽  
E Hall ◽  
...  
Keyword(s):  
Hydrochloric Acid ◽  
Collaborative Study ◽  
Tween 80 ◽  
Mineral Oil ◽  
Improved Method ◽  
Aoac Method ◽  
Light Mineral ◽  
Wet Sieving

Abstract The present official AOAC method (44.120(a)(b), 13th Ed.) for extracting light filth from ground allspice uses flammable solvents and gives poor filth recoveries. An improved method has been developed which uses a single pretreatment with 40% isopropanol and hydrochloric acid, followed by wet sieving. After deaeration by boiling, the light filth is extracted from 40% isopropanol-Tween 80-tetrasodium EDTA with light mineral oil. Reports from all 6 collaborators showed that the proposed method resulted in 90 and 89% average recoveries of rodent hairs and insect fragments, respectively. The proposed method is recommended for adoption as official first action to replace AOAC (44.120(a)(b)) for allspice.

Allyl Isothiocyanate in Mustard Seed

1970 ◽  
Vol 53 (1) ◽  
pp. 1-3 ◽  
Author(s):  
Donald L Andersen
Keyword(s):  
Allyl Isothiocyanate ◽  
Mustard Seed ◽  
Official Method ◽  
Average Recovery ◽  
Aoac Method ◽  
Aoac Official ◽  
Mustard Seeds ◽  
Column Preparation ◽  
Aoac Official Method

Abstract A new GLC method for the determination of allyl isothiocyanate in mustard seed was compared to a method of the Midwest Research Institute and to a combination of the AOAC official method and the proposed method. Twelve collaborators compared the AOAC method and the GLC method, using whole mustard seeds. Each collaborator assayed three seed portions by both methods. The range, standard deviation, and coefficient of variation are less for each seed portion by the proposed than by the official method. The average recovery value of allyl isothiocyanate in the prepared standard solutions is lower, using the proposed GLC procedure, but seed assay values are significantly and consistently higher for each seed portion when compared with the results for the AOAC method. Reports from the collaborators also indicate that the proposed method is rugged, as the GLC column preparation was subjected to many changes. It is recommended that the GLC method be adopted as official first action.

Collaborative Study of the Quantitative Gas-Liquid Chromatographic Determination of Fusel Oil and Other Components in Whisky

1972 ◽  
Vol 55 (3) ◽  
pp. 549-556
Author(s):  
J H Kahn ◽  
E T Blessinger
Keyword(s):  
Ethyl Acetate ◽  
Collaborative Study ◽  
Chromatographic Determination ◽  
Official Method ◽  
Fusel Oil ◽  
Fusel Alcohols ◽  
Aoac Method ◽  
Liquid Chromatographic Determination ◽  
Liquid Chromatographic

Abstract Fifteen chemists participated in a collaborative study for the quantitative pas-liquid chromatographic determination of the individual fusel alcohols and ethyl acetate in whisky. Two levels of congeners represented by 4 coded samples of whisky were analyzed by using t h e proposed method, employing a glycerol-1,2,6-hexanetriol column, and the official AOAC method, 9.063-9.065. Since isobutyl and the atnyl alcohols comprise by far the greatest part of fusel oil, their determination is of major importance to the total fusel oil content . Statistical analyses show that the proposed method is superior to the AOAC method for the determination of these alcohols, whereas the official method is superior for the determination of ethyl acetate and n-propyl alcohol. In general, collaborators employing modern instrumentation preferred the proposed method over the AOAC method. The former method also separates and permits the quantitative measurement of active amyl and isoamyl alcohols. The proposed method has been adopted as official first action as an alternative to 9.063–9.065 for the determination of higher alcohols and ethyl acetate in whisky.

scholarly journals Comparative Validation Study to Demonstrate the Equivalence of a Minor Modification to AOAC Method 997.03 [Visual Immunoprecipitate (VIP®) for Listeria] to the Reference Culture Methods

2008 ◽  
Vol 91 (2) ◽  
pp. 365-369 ◽  
Author(s):  
Philip T Feldsine ◽  
David E Kerr ◽  
George S Shen ◽  
Andrew H Lienau
Keyword(s):  
Official Method ◽  
Comparison Study ◽  
Culture Methods ◽  
Environmental Surfaces ◽  
Environmental Surface ◽  
Aoac Method ◽  
Aoac Official ◽  
A Minor ◽  
Comparative Validation ◽  
Aoac Official Method

Abstract The Visual Immunoprecipitate (VIP®) for the Detection of Listeria in Foods and Environmental Surfaces, AOAC Official Method 997.03, has been modified to use a simplified housing for the device. A methods comparison study was conducted to demonstrate the equivalence of this modification to the reference culture methods. Two food matrixes and one environmental surface were analyzed. In total, valid results were obtained from 145 samples and controls. Results showed that the modified VIP for Listeria spp. is equivalent to the reference culture methods for the detection of Listeria.

scholarly journals Improved method for determination of waxes in olive oils: reduction of silica and use of a less hazardous solvent

OCL ◽  
2020 ◽  
Vol 27 ◽  
pp. 20
Author(s):  
Andrea Milani ◽  
Paolo Lucci ◽  
Martina Sedran ◽  
Erica Moret ◽  
Sabrina Moret ◽  
...  
Keyword(s):  
Silicic Acid ◽  
Solid Phase ◽  
Internal Standard ◽  
Solvent Mixture ◽  
Official Method ◽  
Improved Method ◽  
Capillary Gc ◽  
Olive Oils ◽  
Solid Phase Extraction Cartridge

The evaluation of the content of waxes is request both by IOC Trade Standard and by Regulation (EEC) 2568/91 and its further amendments. The official method uses 15 g of silicic acid and elutes several fractions by using huge volumes of dangerous solvent (n-hexane). The developed method uses 1 g of silicic acid with a different particle size and less than 20 mL of solvent mixture, substituting n-hexane with less toxic isooctane. Briefly, after spiking with a suitable internal standard, oil sample is fractionated by SPE (Solid Phase Extraction) cartridge with 1 g of silica, waxes are eluted with 14 mL of isooctane/ethyl ether 99/1 (6 mL discarded and 8 mL collected), then, after elution sample is reconstitute in 200 μL of n-heptane and analysed by capillary GC. Data of “In home” validation, (repeatability, accuracy and recovery) and relative chromatograms are reported in this paper.

Collaborative Study of the Determination of Phosphorus in Gelatin, Dessert Preparations, and Mixes

1972 ◽  
Vol 55 (3) ◽  
pp. 581-582
Author(s):  
Roger G Burkepile
Keyword(s):  
Collaborative Study ◽  
Official Method ◽  
Standard Samples ◽  
Preliminary Work ◽  
Aoac Method ◽  
Standard Deviations

Abstract A collaborative study of the proposed method for phosphorus in gelatin, dessert preparations, and mixes has been conducted. The present AOAC method for phosphorus in fertilizers, 2.023–2.025(a), was modified for this study. Preliminary work by the Associate Referee involving 4 phosphorus standard samples compared the proposed method with the official final action AOAC method for gelatin, 23.004. Additionally, phosphorus standard spikes in gelatin at the 1 and 10 mg P2O5, levels were determined by the proposed method. The proposed method is faster and more sensitive than the official method and is as accurate. Five collaborators and the Associate Referee analyzed 4 prepared samples containing various levels of phosphorus by the proposed method. The standard deviations varied from 0.005 for a 225 Bloom gelatin containing an average of 0.273% P2O5 to 0.016 for a strawberry-flavored commercial gelatin with added lecithin containing an average of 0.110% P2O5. The proposed method has been adopted as official first action to replace 23.004, which was repealed, official first action.

Extraction of Light Filth from Whole Leaves of Alfalfa, Lemon Balm, Papaya, and Spearmint: Collaborative Study

1987 ◽  
Vol 70 (6) ◽  
pp. 997-999
Author(s):  
Marvin J Nakashima ◽  
Larry E Glaze
Keyword(s):  
Collaborative Study ◽  
Tween 80 ◽  
Mineral Oil ◽  
Test Portion ◽  
Lemon Balm ◽  
Aoac Method ◽  
Wet Sieving

Abstract Results are reported for a collaborative study to extend AOAC method 44.A06-44.A08 to extraction of light filth from whole leaves of alfalfa, lemon balm, papaya, and spearmint. A 5 g (spearmint) or 10 g (alfalfa, lemon balm, papaya) test portion is defatted with isopropanol in a simple reflux apparatus. Rat hairs, insect fragments, and whole insects are isolated by wet sieving on a No. 230 sieve, a deaerating boil in 40% isopropanol, and flotation with mineral oil-heptane (85 + 15) from Tween 80-Na„EDTA (1 + 1) and 40% isopropanol in a Wildman trap flask. Each product was spiked at a different level. For rat hairs, recoveries averaged 82.2% from alfalfa, 88.9% from lemon balm, 80.6% from papaya, and 79.6% from spearmint. Recoveries of whole or equivalent insects from these products averaged 66.1, 218.8, 69.4, and 85.4%, respectively; recoveries of insect fragments from these products averaged 89.6, 94.4, 94.1, and 88.1%, respectively. The method has been adopted official first action for extraction of light filth from whole leaves of alfalfa, papaya, and spearmint. The extension of the method to lemon balm was not recommended because of interferences by intrinsic whole insects, which were the same species as the spike material.

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