New Method for the Extraction of Light Filth from Whole and Granulated Nutmeats

Abstract A new method has been developed which is applicable to all nutmeats, with or without testa, either raw, dry, or oil roasted. Nutmeats are defatted by a 10 min boiling in chloroform (pecans require 3 defattings), after which the solvent is removed by aspiration and an isopropanol rinse. Following a short boiling deaeration and acid hydrolysis, light filth elements are extracted with mineral oil from a mixture of 60% ethanol and calcium chloride. Collaborative trials by the proposed method for nutmeats (except pecans) yielded significantly cleaner extraction papers and better recoveries of all light filth spike elements than by the official method. In addition, the proposed method resulted in reductions of coefficients of variation ranging from 47 to 93% of that for the official method. The modification for pecans, included in this method, required more extensive defatting and also resulted in improved light filth recoveries and reductions in coefficients of variation. Not all varieties of nutmeats were collaboratively studied; however, intralaboratory recovery trials on these nutmeats proved the proposed method superior to the official methods. The method is recommended for adoption as official first.

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Collaborative Study of a New Method for the Extraction of Light Filth from White Flour

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/55.3.514 ◽

1972 ◽

Vol 55 (3) ◽

pp. 514-515

Author(s):

Mary T Miller

Keyword(s):

Acid Hydrolysis ◽

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

White Flour

Abstract A new method for the separation of light filth from white flour is based on an autoclave-acid hydrolysis, followed by separation of light fdth elements with mineral oil in a Corning or Kilborn separator. This method is rapid and gives clean papers and good recoveries. The method has been adopted as official first action, to replace 40.045 and 40.046 for extraction of light filth from white flour.

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Collaborative Study of a New Method for Extraction of Light Filth from Reconditioned (Coarsely Ground) Nutmeg

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/54.3.575 ◽

1971 ◽

Vol 54 (3) ◽

pp. 575-578

Author(s):

Alberto W Vazquez

Keyword(s):

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

Official Method ◽

Collaborative Testing

Abstract A new method has been developed for extraction of light filth from coarsely ground nutmeg. Nutmeg tissue is defatted by 3 successive 10 min extractions with boiling CHCI3, after which the solvent is removed by aspiration and an isopropanol rinse. Following sieving on a No. 230 sieve and a brief deaeration and hydrolysis step in acidified boiling 60% ethanol-CaCl2, light filth elements are extracted with mineral oil from the 60% ethanol-CaCl2 mixture. Collaborative testing of the proposed method yielded satisfactory recoveries of added light filth elements. The official method for ground spices, 40.106(b), was compared in a collaborative study with the proposed method for the analysis of ground nutmeg and mace. Results were encouraging, but further study is indicated. The method as described for reconditioned nutmeg has been adopted as official first action.

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Collaborative Study of a New Method for the Extraction of Light Filth from Ground Coffee

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/55.1.57 ◽

1972 ◽

Vol 55 (1) ◽

pp. 57-59

Author(s):

Joel J Thrasher

Keyword(s):

Hydrogen Peroxide ◽

Carbon Tetrachloride ◽

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

Official Method ◽

Peroxide Bleaching ◽

Filter Papers ◽

Analytical Time ◽

Ground Coffee

Abstract A collaborative study has been completed on a new method for light filth in ground coffee. The sample is defatted with chloroform, dried, and boiled in water; isopropanol is added and the sample is boiled again. Light filth is trapped off with mineral oil from a hot solution. The method yields better recoveries of insect fragments and rodent hairs than the official method. Other advantages are less analytical time, cleaner filter papers, and elimination of the use of carbon tetrachloride. It is recommended that the method be adopted as official first action to replace 40.007(b) for the isolation of light filth from ground coffee and that the hydrogen peroxide bleaching technique described earlier be adopted as a procedure to replace the sodium hypochlorite technique described in 40.006.

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Collaborative Study of an Acid Autoclave Method for Mineral Oil Extraction of Light Filth from Spaghetti and Macaroni

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/52.3.463 ◽

1969 ◽

Vol 52 (3) ◽

pp. 463-465

Author(s):

Joel J Thrasher

Keyword(s):

Collaborative Study ◽

Mineral Oil ◽

Oil Extraction ◽

New Method ◽

Official Method ◽

Plain Weave ◽

Filter Papers ◽

Wet Sieving ◽

Better Than

Abstract A method for the extraction of light filth from alimentary pastes based on rapid autoclaving of acidified samples, wet sieving on a No. 230 plain weave sieve, and heating the sieve retainings in an acidic mineral oil mixture is described. This new method is faster and results in higher and more reproducible recoveries than method 36.025. Recoveries were equal or better than those achieved by the official method, and the filter papers were cleaner.

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Extraction of Light Filth from Ground Nutmeg: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/62.3.595 ◽

1979 ◽

Vol 62 (3) ◽

pp. 595-596

Author(s):

Joel J Thrasher

Keyword(s):

Plant Material ◽

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

Official Method ◽

Additional Problem

Abstract The official method for extracting light filth from ground nutmeg, 44.116, gives variable recoveries of filth elements and results in large amounts of interfering plant material in the light filth extraction. A new method has been developed using a chloroform pretreatment for heavy filth followed by a water-40% isopropanol- mineral oil flotation of light filth. A comparison of the methods in the collaborative study showed a higher recovery of insect fragments, 90.6 vs. 65.2%, and of rodent hairs, 86.5 vs. 66.5%, for the new method over the present official first action method, 44.116. Frothing, an additional problem with the official method, has been reduced by the new method. The new method has been adopted as official first action to replace the existing method.

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Comparison of Three Methods for Determination of /V-Nitrosopyrrolidine in Fried Dry-Cured and Pump-Cured Bacon

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/71.3.504 ◽

1988 ◽

Vol 71 (3) ◽

pp. 504-508

Author(s):

Anthony J Malanoski ◽

Wertice J Smith ◽

Thomas Phillipo

Keyword(s):

Low Temperature ◽

Thermal Energy ◽

Validation Studies ◽

Vacuum Distillation ◽

Mineral Oil ◽

Energy Analyzer ◽

Coefficients Of Variation ◽

The Individual

Abstract Three methods, the mineral oil distillation (MOD), the dry column (DC), and a low temperature vacuum distillation (LTVD), for the determination of iV-nitrosopyrrolidine in dry-cured and pump-cured bacon were compared. Each method uses the thermal energy analyzer for the determinative step. The coefficients of variation for repeatability were 10.3% (MOD), 7.2% (DC), and 9.1% (LTVD) for the dry-cured bacon study and 8.7% (MOD), 8.5% (DC), and 7.1% (LTVD) for the pump-cured bacon study. The pooled coefficients of variation for between-method reproducibility were 11.8% for the drycured bacon and 10.8% for the pump-cured bacon. The pooled coefficients of variation for repeatability were 9.0% for the dry-cured bacon and 8.2% for the pump-cured bacon. These values compare favorably with the values from previous collaborative or validation studies of the individual methods, and the methods can be considered to be equivalent

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Extraction of Light Filth from Canned Green Leafy Vegetables: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/62.3.600 ◽

1979 ◽

Vol 62 (3) ◽

pp. 600-601

Author(s):

Russell G Dent ◽

Jack L Boese

Keyword(s):

Plant Material ◽

Collaborative Study ◽

Excessive Amount ◽

Leafy Vegetables ◽

New Method ◽

Official Method ◽

Green Leafy Vegetables

Abstract The official first action method, 44.108, for the extraction of light filth from whole or chopped canned greens specifies a waterheptane flotation that results in the flotation of an excessive amount of interfering plant material and in low recoveries. A new method has been developed using a 40% isopropanol-watermineral oil flotation. The new method yielded a decreased amount of plant material and 84.9% recovery of the aphid spike compared with 42.5% recovery of the spike by the official method. The new method has been adopted as official first action to replace the existing method, except for broccoli.

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Collaborative Study of a Method for the Extraction of Light Filth from Ground Mace and Ground Caraway Seed

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/59.4.827 ◽

1976 ◽

Vol 59 (4) ◽

pp. 827-829

Author(s):

Joel J Thrasher

Keyword(s):

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

Filter Papers

Abstract A new method has been developed for the extraction of light filth from ground mace and ground caraway seed. The method uses a 2-step chloroform-isopropanol pretreatment followed by separation of the light filth from 40% isopropanol with mineral oil. The collaborative study resulted in clean filter papers with more reproducible recoveries of light filth elements than the official first action method, 44.116(b). The method has been adopted as official first action.

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Collaborative Study of a Method for the Extraction of Light Filth from Crushed Red Peppers

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/58.3.445 ◽

1975 ◽

Vol 58 (3) ◽

pp. 445-446

Author(s):

Joel J Thrasher

Keyword(s):

Collaborative Study ◽

Mineral Oil ◽

New Method ◽

Collaborative Studies ◽

Red Peppers

Abstract A new method was developed for the extraction of light filth from crushed red peppers. The method utilizes an isopropanol defatting of the product followed by separation of light filth elements with mineral oil and n-heptane (85+15) in a 2 L trap flask. Collaborative studies resulted in good recoveries of light filth spike elements and clean extraction papers. The method has been adopted as official first action.

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Extraction of Light Filth from Tea: Collaborative Study

Journal of AOAC INTERNATIONAL ◽

10.1093/jaoac/64.2.287 ◽

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.

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