Food control quality by isotope dilution liquid chromatography-tandem mass spectrometry

The late part of the 20th century the advancement of knowledge regarding nutrition and\ndisease prevention provided an opportunity for individuals to affect their own health.\nThis expanding body of information helped people to understand how the environment\nand their own behaviour affected their body. People now had powerful tools to help\nmaintaining and protecting their health. The understanding of how our diet affects our\nwell being has dramatically changed the lifestyles and attitudes of people, who began to\nmake menu and purchasing decisions based on how foods would affect their heath. A\nshift toward healthier lifestyles and healthier diets began. Food processors and marketers\nhad to refocus their efforts from promoting foods for pleasure to promoting foods that fit\nin to a healthy diet. Primarily, the focus was on reducing fat and cholesterol in the diet\nand supplementing vitamins and minerals. Research began to demonstrate the presence\nof various phytochemicals in wine and juice make it from fruits and vegetables( such as\nstilbenes, falvoniods, polyphenols…) and specially in olive oil as ( polyphenol in\ndialdehyed form: oleochanthal, hydroxyoleocanthal..) These compounds have come to\nbe known as nutraceuticals. The list of nutraceuticals present in wine, fruit drink and\nolive oil that are believed to have positive biological properties has been expanding.\nFood processors and developers have become very interested in exploiting these\nnutraceuticals for the production of foods that are not only part of a healthy diet but also\nimprove the consumer’s health in another specific way. These foods have become\nknown as “functional foods” means quality marker.\nThe aim of this thesis has been to develop a analytical methods to determine the\nconcentration of a group of these nutraceuticals in food , such as, quantitative\ndetermination of resveratrol in wine, pterostilbene in blueberry juice and dialdehyde\nform in olive oil using a sensitive high-performance liquid chromatographic separation\nmethod coupling with tandem-mass and isotope dilution to order to optimal the\nconditions for the analysis method, such as extraction procedure, matrices, column,\nquality controls, wavelength, mobile phases, run time, optimal separation (gradient,\nretention times), temperature, capillary voltage, cone voltages, vacuum and labelled\ninternal standards, resulting in the best sensitivity and selectivity,The goodness and satisfactory of the method was performed according to, containing\nlinear measuring range, quantification, lower limit of quantification (LLOQ), lower limit\nof detection (LLOD), quality controls, precision(RSD %), accuracy, recovery, stability\nand matrix effects.\nIn conclusion, the described high-performance liquid chromatographic separation\nmethod with tandem-mass spectrometry detection and isotope dilution showed a\nsatisfactory overall analytical performance well suited for applications in food quality\ncontrol.