Rapid Species Identification of Cooked Red Snapper Using Isoelectric Focusing

Abstract

A rapid method using isoelectric focusing (IEF) was developed to identify species of cooked snapper. The IEF protein band patterns of red snapper as impacted by two extraction systems (water and 8M urea), various cooking times (raw, 5, 10, 15, 20, 25 and 30 min) and cooking methods (microwave, bake, steam, broil, deep fry, and pan fry) were investigated. Samples were desalted and cleaned using a 10-sec rinsing procedure. The characteristic IEF protein pattern of red snapper was reproducible for various cooking conditions. Both 8M urea and water could be used as extractant of snapper sarcoplasmic proteins. IEF protein bands in the acidic region of the polyacrylamide gel (pH 3.5-9.5) were useful as markers for species identification.

Computer-assisted evaluation of isoelectric focusing patterns in electrophoretic gels: Identification of smoothhounds(Mustelus mustelus, Mustelus asterias) and comparison with lower value shark species

“…In fact there is no significant difference between the two, both from a morphological and a commercial point of view. We selected IEF on broad pH (3.5-9.5) polyacrylamide gels, as it is a well-established and widely utilized [4][5][6][7][8][9][10][11][12][13][14][15][16][17][18], while relatively simple, [14,19], although recently improved analytical strategies have been developed (for example, using parvalbumins as proteins of choice in fish identification [20]), performing the electrophoretic run with either CleanGels or immobilized pH gradient gels, IPGs [21]. Many less valuable shark species are sold under the generic name "smoothhound", thus committing fraudulent substitution by mislabeling the products.…”

Molecular identification and Phytogeny of the tow freshwater fish Bagrus bajad and Bagrus docmac in Egypt

“…Protein-based identification techniques become less reliable with fish. However, in some cases, it is still possible to generate a banding pattern which enables identification (Hsieh et al, 1997). As an alternative to protein analysis, DNA-based identification techniques have been proposed and applied.…”

Species Substitution of Restaurant Fish Entrees

“…All samples were half-frozen or chilled in ice upon receiving. Samples were immediately cleaned by rinsing with deionized water for 10 s to remove salt, spices, and gravy (Hsieh et al 1997). About 5 g of flesh was removed from the center of each sample and homogenized with 1:l (w/v) 8M urea for cooked snapper samples or distilled water for raw fish and cooked swordfish samples.…”

“…Recently, a simple and rapid rinsing technique was developed in our laboratory to effectively clean and desalt variously cooked snapper for species identification using IEF (Hsieh et al 1997).…”