Effects of polyphosphates and sodium chloride on heterocyclic amines in roasted beef patties as revealed by UPLC-MS/MS.

The effects of sodium tripolyphosphate (TPP), sodium pyrophosphate (PP), and NaCl at different ionic strengths on the formation of heterocyclic amines (HAs) were investigated in roasted beef patties. Six HAs (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine [PhIP], 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline [MeIQx], 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline [4,8-DiMeIQx], 2-amino-3-methylimidazo[4,5-f]quinoline [IQ], 1-methyl-9H-pyrido[3,4-b] indole [harman], and 9H-pyrido[3,4-b] indole [norharman]) were identified and quantified. The presence of 0.3% and 0.45% PP significantly increased the formation of PhIP (P < 0.05). Different levels of TPP/PP had no effect on MeIQx, 4,8-DiMeIQx, IQ, norharman, or harman (P > 0.05), but these products increased in the presence of NaCl at three ionic strengths and NaCl + 0.3% and 0.45% TPP/PP (P < 0.05). High hardness and surface temperatures were observed after treatments with NaCl and NaCl + TPP/PP. The increase in these six HAs in beef patties with the addition of polyphosphates and NaCl did not involve changes in pH, but mainly stemmed from higher surface temperatures during roasting.

Preparative purification of salidroside from Rhodiola rosea by two-step adsorption chromatography on resins.

Salidroside is an effective adaptogenic drug extracted from Rhodiola species. In the present study, a simple and efficient method for preparative separation and purification of salidroside from the Chinese medicinal plant Rhodiola rosesa was developed by adsorption chromatography on macroporous resins. The static adsorption isotherms and kinetics of some resins have been determined and compared for preparative separation of salidroside. According to our results, HPD-200 resin is the most appropriate medium for the separation of salidroside and its adsorption data fit the Langmuir isotherm well. Dynamic adsorption and desorption were carried out in glass columns packed with HPD-200 to optimize the separation process. After two adsorption and desorption runs, a product with a salidroside content of 92.21% and an overall recovery of 48.82% was achieved. In addition, pure lamellar crystals of salidroside with a purity of 99.00% could be obtained from this product. Its molecular weight was determined by an ESI-MS method. The simple purification scheme avoids toxic organic solvents used in silica gel and high-speed counter-current chromatographic separation processes and thus increases the safety of the process and can be helpful for large-scale salidroside production from Rhodiola rosea or other plant extracts.

Chemical composition of clarified bayberry (Myrica rubra Sieb. et Zucc.) juice sediment.

Clarified bayberry juice turned hazy upon storage at 25 degrees C for 6 months, and the chemical composition of centrifugally separated sediment was analyzed. Bayberry juice haze was mainly protein-tannin haze. The lyophilized sediment contained 20.4 +/- 4.3% of protein, 70.2 +/- 2.6% of total polyphenols, 7.2% of monosaccharides, and 6.7 +/- 0.6% of ash. Amino acid analyses and molecular weight distribution estimation indicated that bayberry proteins were haze-active proteins with a molecular weight less than 8 kDa. Gallic acid, quercetin hexoside, quercetin deoxyhexoside, and quercetin were found in the methanol-dissolved sample, while gallic acid, protocatechuic acid, cyanidin, ellagic acid, and quercetin were detected in the acid-hydrolyzed sample. Ellagic acid was the dominant individual phenolic (9.9 +/- 0.19 g/100 g dry weight, 55.3% of the total amount) in the sediment. Monosaccharides of rhamnose, arabinose, mannose, glucose, and galactose in the sediment were most probably the glycoside moieties of the anthocyanins, flavonols, and elllagitannins. Metal ions of calcium, magnesium, potassium, iron, and copper also indicated the heterogeneous characteristics of the sediment.