The impact of Maillard compounds on the quality and safety of uht milk foods and their implication in the development of diabetes-like complications
PN2-RU-TE-2013-3-0034, NUMBER 15/26.04.2013.
The present web page represents the presentation of the roumanian research project for young researches : The impact of Maillard compounds on the quality and safety of uht milk foods and their implication in the development of diabetes-like complications, PN2-RU-TE-2013-3-0034, NUMBER 15/26.04.2013. funded by The Executive Unit for funding Superior Education,Research, Development and Innovation (UEFISCDI) http://uefiscdi.gov.ro/
The major objective of this project is to study and characterize the Maillard products which appear during UHT processing and storage of milk based foods and their effect on human health that until today remained under question. Moreover, this project focuses on identifying an adequate AGE-marker to evaluate the level of protein modifications by Maillard reaction and to correlate the reducing nutritional value and the toxicity of the heat-processed foods that could be used in the quality and safely control of foods.
The children’s alimentation is rich in dairy products and for this reason, we want to study the degree of protein modifications by Maillard reaction of UHT milk with chocolate or fruit juices (concept ready-to-eat), that have an extended shelf life.
This research has a complex feature because the objectives could be subheading in three categories: in vitro glycation studies, in situ glycation studies and cells cultures studies
1. In vitro glycation studies of caseins fractions and β-lactoglobulin with reducing sugars (glucose or fructose). These studies are necessary because they offer a good model to control a multitude of parameters (temperature, pH, concentration of proteins and reducing sugar, activity of water) involved in the Maillard reaction.
2. In situ glycation studies to evaluate the degree of Maillard modification of milk-proteins from UHT milk with chocolate or fruit juice. The quality of the raw material (the ratio between lactose and protein contents), the heating treatments applied to ensure the safety of milk and to extend shelf life, the added reducing sugar (glucose-fructose syrup) and aroma (chocolate or fruit juice), and the storage conditions (20-30˚C) favor the Maillard reaction and affect the quality of UHT milk with different aroma. As a consequence of the heating treatments, milk undergoes chemical and biochemical changes that affect different components, mainly proteins, carbohydrates and vitamins . This gives rise to physical modifications such as changes in color and particle size and biochemical alterations as a consequence of interactions between the amino acid lateral groups, degradation reactions of lateral chains of the proteins, restructuring of –SH groups, insolubility of whey proteins, interactions between k-casein and β-lactoglobulin, and between carbohydrates and proteins . Therefore, analytical methods for monitoring the effect of heating treatments on milk quality in relation with the development of Maillard compounds are necessary.
3. Cell cultures studies. Evaluation of citotoxicity, oxidative stress and RAGE signaling pathways induced by AGEs derived from glycated-milk proteins on human intestinal fibroblast and kidney cultured cells. Estimation the critical levels of AGEs. Only limited data on the effect of glycation compounds present in food on the animal and human health are available at the time being. Vlassara and co-workers demonstrated that modulation of oral AGEs that diabetic subjectsintake have triggered changes in the inflammation markers, linked to diabetes and vascular dysfunction . Therefore, reduced consumption of these AGE-products which are present in foods may prove to be a safe economic policy in order to prevent AGEs-related diseases. An original approach of this research is to study the impact of AGEs modified food proteins concerning the cytotoxicity, oxidative stress and RAGE pathways on intestinal and embryonic kidney cultured human cells because the small intestine is the gate of insight in organism of AGEs-diets and in diabetes complications, the kidney is an important target. The obtained results will lead to an estimation of the critical level of AGEs at which the presence of these compounds has a harmful effect on human cells.