Electronic sorting

It turned out that meeting a 20 ppb limit was not excessively burdensome on major manufacturers of peanut butter and other peanut products, at least in the United States aflatoxin tended to concentrate in discolored or otherwise irregular peanuts, which, fortunately, could be picked up and rejected by modern electronic sorting machines. Manufacturers did, however, have to institute substantial additional quality control procedures to meet FDA limits, and many smaller manufacturers had trouble meeting a 20 ppb limit. An extensive USDA program of sampling and analysis of raw peanuts, which continues to this day, was also put into place as the first line of attack on the problem. 

There are only a few commercial uses for europium. Europium oxide, (Eu O ), a compound of europium, is added to infra-sensitive phosphors to enhance the red colors on TV and computer-monitor picture tubes. It is also added to fluorescent light tubes to increase their efflciency, as well as to some materials to make lasers. Since it is a good neutron absorber, it is part of nuclear reactor control rods. Europium is an additive to the glue used on postage stamps, thus making it possible for the electronic sorting machines in U.S. postal offices to read the stamps. 

The data which yield a spectrum can be obtained with a system in which measurements are made at one velocity at a time (the transducer motion during the measurement is held at constant velocity) or, preferably, by changing the velocity through a range at constant acceleration and electronically sorting the y-ray intensity data obtained as a function of the changing source velocity. 

Automatic electronic sorting equipment is being used to some extent and soon will be the major method, as faster and better electronic sorting equipment is developed and put to use. 

Removal or elimination of mycotoxins. Since most of the mycotoxin burden in contaminated commodities is localized to a relatively small number or seeds or kernels [reviewed in Dickens, 200], removal of these contaminated seeds/kemels is effective in detoxifying the commodity. Methods currently used include (a) physical separation by identification and removal of damaged seeds, mechanical or electronic sorting, flotation and density separation of damaged or contaminated seeds (b) removal by filtration and adsorption onto filter pads, clays, activated charcoal (c) removal of the toxin by milling processes and (d) removal of the mycotoxin by solvent extraction. 

Although manual sorting is applied in many cases to separate waste materials, its application is not ideal due to the high labor cost and human errors. Opto-electronic sorting is an automated sorting process of waste materials in replacement of manual sorting, based on waste particle characteristics such as brightness, transparency, color, shape, and size. 

Opto-electronic sorting systems can process waste with particle size from 5 to 250 mm. Color sorting of particles is very difficult or impossible for size less than 5 mm, under the current state of the art. Capacity ranges from 2 to 200... 

Figure 10 Operating principle of electronic sorting. (With permission from Ref. 11.)...

Anon. 1987 Electronic sorting reduces labour costs. Food Technology in New Zealand, 47. 

Identified in green immature beans by Full et al. (2000), after electronic sorting of the beans followed by simultaneous distillation-extraction. 

Full G., Lonzarich V. and Suggi-Liverani F. (2000)) Differences in chemical composition of electronically sorted green coffee beans. 18th Int. Colloq. Chem. Coffee (Helsinki, 2-6.8.1999) (ASIC, 2000), 35-42. 

In energy dispersive instruments, all the characteristic X-rays from the specimen are first detected by a high resolution solid state detector. The detector output consists of electrical pulses of amplitude proportional to the energy of the detected photons. These pulses, once linearly amplified, are electronically sorted according to their amplitude by means of a pulse height analyzer. An advantageous consequence of this detection mode is that analysis of all chemical elements can be performed simultaneously. Since it eliminates the use of crystal goniometers and the X-rays are not spatially dispersed, this type of spectrometer is also sometimes referred to as nondis-persive. 

If an online collection is not within the budget, then selected hard copy or online editions should be purchased. Using the reviews in Choice or SciTech Book News, or conducting a search in WorldCat can be helpful to determine recent and popular titles in particnlar areas. For example, a WorldCat title search on handbook or mannal or dictionary or encyclopedia and electronics, sorted by publication date, gives a selection of titles that could be added to the collection. 

PROCESSING. Almonds are sold unshelled or shelled. They are shelled mechanically, and then the kernels are electronically sorted for defects, graded for size, and packaged. Shelled almonds may also be salted and roasted, blanched, ground into a meal or made into a paste. 

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