Peanut grading

The results of this study further substantiated previous studies that the new ELISA screening tests provide an excellent opportunity to implement a direct analytical method at peanut grading points. 

Cole, R. J. Domer, J. W. Kirksey, J. W. Dowell, F. E. Comparison of visual, enzyme-linked immunosorbent assay screening, and HPLC methods in detecting aflatoxin in farmers stock peanut grade samples. Peanut Sci., 15 61-3. 1988. 

A process has been developed (139) whereby up to 80% of the oil can be removed from whole, raw peanuts without the use of solvent. In this process, the blanched peanuts are brought to a proper moisture content, pressed mechanically, and then reshaped or reconstituted by dipping in hot water subsequently they can be roasted and salted, or used in confections or other formulations. Defatted peanuts may also be ground into meal and added to cookies, cakes, and many other products, where they impart a distinctly nutty flavor and cmnchy texture. On the other hand, the resulting high grade oil is refined and employed in cooking and industrial products. This process can also be used for pecans, walnuts, almonds, Brazil nuts, cashews, and other nuts (140-142). 

Solvent Extraction. Extraction processes, used for separating one substance from another, are commonly employed in the pharmaceutical and food processing industries. Oilseed extraction is the most widely used extraction process on the basis of tons processed. Extraction-grade hexane is the solvent used to extract soybeans, cottonseed, com, peanuts, and other oilseeds to produce edible oils and meal used for animal feed supplements. Tight specifications require a narrow distillation range to minimize solvent losses as well as an extremely low benzene content. The specification also has a composition requirement, which is very unusual for a hydrocarbon, where the different components of the solvent must be present within certain ranges (see Exthaction). 

The term waste heat boiler is also widely used to cover heat recovery boilers (HR boilers), which tend to be direct-fired steam generators, albeit employing low-grade by-product fuels such as bagasse, wood bark, com cobs, peanut shells, blast furnace gas, black liquor, and the like. 

Catfish (Clarias batrachus) plasma vitellogenin levels were significantly decreased after 48 hours of exposure to 0.0015 mg/L of commercial-grade endosulfan (Chakravorty et al. 1992). Levels did not recover substantially with injections of various hormones, including estradiol. In rainbow trout, endosulfan did not induce vitellogenin production at 9 days after a single intraperitoneal injection of 5 mg/kg in peanut oil (Andersen et al. 1999). 

When oils are used as vehicles in ophthalmic fluids, they must be of the highest purity. Vegetable oils such as olive oil, castor oil, and sesame oil have been used for extemporaneous compounding. These oils are subject to rancidity and, therefore, must be used carefully. Some commercial oils, such as peanut oil, contain stabilizers that could be irritating. The purest grade of oil, such as that used for parenteral products, would be advisable for ophthalmics. 

Fullerenes were high purity grades (99 + %) from Southern Chemicals LLC. Vegetable oils were commercially available oils from olive, linseed, soybean, sunflower, peanut and castor. A methyl ester of brassica oilseed also was employed. 

A murine model of food-induced atopic dermatitis confirmed the important role of specific T cells in eczema here, C3H/HeJ mice were orally sensitized to cow s milk or peanut and thereafter exposed to the allergen. An eczematous eruption developed in approximately one third of mice after low-grade exposure to milk or peanut proteins. Histological examination of lesional skin revealed spongiosis and a cellular infiltrate mainly consisting of CD4-I- lymphocytes. 

Sulfur Standard Accurately weigh five 250.0-g samples of food-grade peanut oil. Transfer 0.0, 1.0, 2.0, 3.0, and 4.0 mL of the Dibenzyl Disulfide Solution into the peanut oil samples the samples contain 0, 3, 6, 9, and 12 mg/kg of sulfur, respectively. 

Food-grade butane in a supercritical, low-pressure, liquefied gas extraction procedure has also been described for oil extraction from peanuts (21). The extraction process consists of mixing the liquefied butane with the material to form a slurry. The liquefied gas and oil are moved to a solvent recovery system where the oil is removed from the butane. The oil is pumped from the solvent recovery system to a holding tank, and the butane is then transformed into a gas in the solvent recovery system and transported back to the butane storage tank for reuse. 

The seed coat of peanut is a commercial source of tannins and thiamin and sees limited use in feeds, primarily as a bulking agent in reduced-calorie pet foods. The presence of the seedcoat in meal may lead to a decrease in the availability of lysine (5). This apparent waste product is also used as mulch, fuel, litter for poultry houses, and in the production of a high-grade activated charcoal. 

Quality and quantity of any crop determine its price in the market place. Although quantity is readily measurable, quantity in units of weight or volume, quality is a less readily measurable attribute. Quality pertains to the characteristics of the commodity and varies somewhat according to the perceptions of different individuals. Nevertheless, grades and standards can and have been established for numerous products to describe their quality characteristics. Many current grades and standards including those for peanut crops, are not as useful as they could be, because they do not accurately de.scribe the essential quality characteristics of the product concerned ( ). 

Recent studies conducted to determine the accuracy, speed, and expense of Enzyme-Linked immunosorbent Assay (ELISA) screening methods for aflatoxin are reviewed in light of proposals that such a method be implemented as part of the official grading system for farmers stock peanuts. The studies have shown several of the ELISA methods to be reliable with regard to screening accuracy. This combined with the speed of the analyses and the relatively low costs could make a practical change in the way incoming loads of farmers stock peanuts are evaluated for aflatoxin contamination. 

The U.S. peanut industry is currently considering the feasibility of implementing a new approach for aflatoxin management at the grading point. This involves different sampling and detection methods for more effective aflatoxin control. This paper discusses... 

The results showed 41% of the grade samples determined to be contaminated by visual inspection contained less than 20 ppb aflatoxin when analyzed by both ELISA and HPLC methods 18.7% of peanuts determined to be uncontaminated by visual inspection actually contained aflatoxin with a range of 26-2542 ppb. The results of ELISA and HPLC agreed in 98.6% of the composite sample analyses with the detection of 20 ppb or greater. However, the ELISA screening method failed to give positive tests 12 of 13 times when the aflatoxin content was between 20-43 ppb in the component samples. Samples were analyzed at the rate of one every two minutes when duplicate analyses of ten samples (20 analyses) were performed. 

Olive oil is often illegally adulterated with other less expensive vegetable oils. Oils widely used for this purpose include olive pomace oil, corn oil, peanut oil, cottonseed oil, sunflower oil, soybean oil, and poppy seed oil. °° Among the varions chemical and physical methods employed toward the detection of the adulteration of olive oil by low-grade olive oils and seed oils are (a) Sterol analysis (presence of stigmasterol and 3-sitosterol), (b) alkane analysis (C27, C29, and C31), (c) wax and aliphatic alcohol analysis, (d) fatty acids/(with HPLC) trans fatty acid, and (e) Triacylglycerol. 

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