Beef extract, evaporating

The preservation of meat products by concentration is best illustrated by the preservation of beef extract. It is the evaporated filtrate obtained from new, clean beef, treated to high steam pressure. This extract according to Stutzer contains ... 

In the first reported study (9six samples of milk were obtained in an area of Texas where 2,4,5-T is used for range-land management. The sample preparation scheme was caustic saponification, extraction, chromatography on silica followed by chromatography on alumina. The extract was evaporated to 10-20 pi and TCDD determined by gas chromatography/mass spectrometry (GC/MS). This technology is similar to that reported for beef fat sample preparation (2,3). No 2,3,7,8-TCDD was detected with detection limits of 1-6 ppt. 

Paraquat was determined in milk, beef and potatoes using an El A with pAb. Potatoes were shredded with dry ice. The potato and the meat samples were extracted with HCl after spiking the samples. The acid extracts were evaporated to dryness and reconstituted for the El A. The milk was diluted with phosphate buffer. The EIA was able to detect less than 1 ppb of paraquat in whole milk and down to 2.5 ppb in beef. The efficiency of HCl for extracting potato and ground beef was determined by using methyl- C paraquat. Recoveries between 60 and 70% were obtained. Since paraquat is known to bind tightly to many matrices, recoveries for both matrices were determined after storage of the spiked samples for several days at 21 °C. 

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