An Analytical Contribution to Determine Some Volatile N- Nitrosamines in Meat, Using Gas Chromatography and Flame Ionization Detector (GC-FID)

Conditions for Gas chromatography (GC) equipped with Flame Ionization Detector (FID) were optimized in order to dtermine volatile N-nitrosamine in meat and meat products, using optima XLB (30m × 0.25 mm × 0.25µm) column. Results reveal that the method has a low detection limit with repeatability and linearity and with average recovery ranging from 89% to 105.5% and accepted relative standard deviation

Thin layer chromatography–image analysis method for the determination of monosodium glutamate in food

A simple and low cost thin layer chromatographic (TLC)-image analysis method was developed for rapid determination and quantification of monosodium glutamate (MSG) in some food samples. Chromatographic separation of MSG was achieved on silica gel TLC plates, using n-butanol:glacial acetic acid:water (5:3:1, v/v/v) as the mobile phase and ninhydrin for spot detection. Image analysis of the scanned TLC plate was performed to quantify the amount of MSG, the method was validated and found to be accurate specific reliable and convenient for the analysis of MSG in some food sample.

Studying some effective factors on maillard reaction products (Saccharides–Leucine) system

Four Model Maillard reactions (MRs) have been carried out using Leucine with each of the following Saccharides; aldohexose (glucose, Glc), ketohexose (fructose, Fru), aldopentose (xylose, Xyl) and disaccharide (Lactose, Lac) at 100 °C and for 24hrs. The pH changes with time were monitored during the reactions at different initial reactant ratio. The products of the reactions (MRPs) were then separated by absolute ethanol into low and high molecular weight fractions (LMW & HMW). The four distinct Saccharides–Leucine MRPs were studied by fluorescence and ultraviolet /visible spectrophotometer. The results showed the tendency of Xyl–Leu MRPs to form brown polymers with relatively high reaction rates compared to Fru, Glc and Lac -Leu MRPs respectively. Further characterization of reducing power of the Saccharides – Leu (MRPs) was performed and showed that different Saccharides –LeuHMW (MRPs) had a higher reducing power than LMW ( MRPs).

Preparation of Caramelisation Products and Defining their Reducing Power

Four model caramelisation products (CPs) have been prepared by heating different Saccharides solutions (glucose, fructose, lactose and xylose) at 100°C for 3 hours at different pH( 2.5, 4, 7 and 10). Both Browning and intermediate thermal degradation products {the caramelisation products} were studied using ultraviolet /visible spectrophotometer. Generally, the results showed that CPs increased with increasing heating time, and the formation rate depends upon the type of Saccharides and pH value. The reducing power of the four distinct CPs was defined, also. Among all the Saccharides tested, fructose CPs exhibited the highest reducing power values in alkaline solutions. Finally, the concentration changes of Saccharides during heating were quantitatively defined by using high performance liquid chromatography HPLC.