ترجمه مقاله فرآوری مواد غذایی و محصولات واکنش میلارد - نشریه هینداوی

1- Introduction

The Maillard reaction has been named after the French physicist and chemist Louis Camille Maillard (1878–1936) who initially described it. It is often defined as nonenzymatic browning reaction. While foods are processed or cooked at high temperature, a chemical reaction occurs between amino acids and reducing sugars which generate different flavours and brown colour (Figure 1). So it is often used in food industry for giving food different taste, colour, and aroma.

Based on literature, Hodge (1953) first described the steps involved in Maillard reaction products (MRPs), also known as advanced glycation end-products (AGEs), formation. The whole process of MRPs formation can be divided into three major stages depending on colour formation. At the first stage, sugars and amino acid condense, and following condensation, Amadori rearrangement and 1-amino-1deoxy2 ketose form. In the second stage, dehydration and fragmentation occur in the sugar molecules. Amino acids are also degraded in this stage. Hydroxymethylfurfural (HMF) fission products such as pyruvaldehyde and diacetyl are formed in this intermediate stage. This stage can be slight yellow or colourless. In the final stage, aldol condensation occurs and finally the heterocyclic nitrogenous compounds form, melanoidins, which is highly coloured [1]. Maillard reaction can also take place in living organisms. It has been reported that some MRPs particularly melanoidins have beneficial effects on health such as antioxidative [2] and antibiotic [3] effects. However some reports have also suggested that MRPs such as high carboxymethyl lysine (CML) promote diabetes and cardiovascular diseases while acrylamide acts as a carcinogen [4–6].

There is an ever-increasing preference for instant meal rather than traditional cooking, especially among the new generation of people. It has been reported that people consuming high amount of processed meat, pizza, or snacks develop insulin resistance and metabolic syndrome compared to people having high intake of vegetables and low processed food [7]. MRPs that change during food processing might be one of the important factors for either disease progression or combating diseases. In this review, we have summarized the changes of MRPs which occur during processing of foods.

9- Conclusion and Perspectives

Maillard reaction products have both positive and negative impacts on health. Diverse MRPs act as antioxidants, bactericidal, antiallergenic, antibrowning, prooxidants, and carcinogens. Most of these properties depend on processing of food. High temperature heating makes some food nutritious, whereas some of the foods lose their nutritional value. Many strategies are employed in the food industries to reduce the production of MRPs. For example, acrylamide has been classified as a probable carcinogen to humans by the International Agency for Research on Cancer [65]. During food preparation at high temperature, acrylamides are formed in many types of foods via Maillard reaction [66– 68]. To reduce the amount of acrylamide, asparaginase has been successfully used in laboratory for potatoes and cereals [69, 70]. It has also been reported that injection of CO2 during extrusion process helps to reduce the level of acrylamide [71].

This review was aimed at summarizing our current knowledge regarding the changes in food mediated by Maillard reaction during the food processing steps. This may provide useful insights for those related to food processing facilities..