Analytical Method for Differentiation of Chilled and Frozen-Thawed Chicken Meat
Abstract : Chilled and frozen chicken breast and thigh meat were stored at +4±1 oC and - 20±1 oC, respectively. Maillard reaction between ribose and meat proteins of the chicken samples was initiated. The changes in the ribose-induced Maillard reaction rate during chilled and frozen storage of chicken meat were evaluated on the bases of corrected absorbance values (A420*) and bovine melanoidin equivalent values (mg BME/g). Application of BME as a measure of ribose-induced Maillard reaction rate enables comparability of the data obtained by different spectrophotometers. It was found that the BME values of chicken meat frozen stored for more than 15 days were significantly (P<0.05) lower than BME values of chilled-stored samples. According to the suggested threshold limit values the chicken thigh and breast meat with BME values lower than 30 mg BME/g and 51 mg BME/g, respectively could be classified as frozen-thawed.
Melanoidin formation in cooked meat products
The processes of melanoidin formation in fried meatballs and schnitzel have been studied through a preparative quantitative isolation of the brown pigments. The influence of the duration of using the frying fat on the quantity of the latter has been established. The melanoidins have been characterized by spectra and fractionated using gel chromatography. It has been shown that their content is in direct relationship with the organoleptic properties of the end products.
Effect of Soybean Cyst Nematode (Heterodera glycines) on Yield of Resistant and Susceptible Soybean Cultivars Grown in Ohio.
Soybean (Glycine max) producers in Ohio rarely use soybean cyst nematode (Heterodera glycines, SCN)-resistant cultivars because of concerns over limited yield potential and lack of resistance to Phytophthora sojae. A two-year study was initiated to determine grain yield and nematode population increase on soybean cyst nematode-resistant cultivars in maturity groups II and III in production fields. Sites differed in soil texture, nematode densities, and P. sojae infestation at a number of locations in Ohio. Soil was assayed for nematode densities before planting and at harvest. Yields of resistant cultivars averaged 0% to 18% higher than those of susceptible cultivars in fine-textured soils with average preplant populations ranging from 463 to 14,330 SCN eggs/100 cm(3) soil. In coarse-textured soils, yields of susceptible cultivars were 21% to 56% less than the resistant cultivars with average preplant densities ranging from 1,661 to 15,558 SCN eggs/100 cm(3) soil. The reproductive index ranged from 0.1 to 5.5 for resistant cultivars and 0.4 to 112 for susceptible cultivars. In 1993, yield of P. sojae-susceptible, nematode-resistant 'Asgrow A 3431' was as high as yield of the P. sojae-resistant, nematode-susceptible cultivar 'Resnik' in a Phytophthora-infested field. The nematode-resistant cultivars Madison Experimental 131527 and Asgrow A3431 had higher yields than AgVenture AV1341 and susceptible cultivars Resnik and Kenwood when compared over five nematode-infested sites. Nematode-resistant cultivars were found to be excellent alternatives to currently grown susceptible cultivars for managing SCN where group III cultivars are used. However, better cultivar alternatives may be needed for sites with combined Phytophthora root rot and cyst nematode problems.