The Maillard Reaction Application to Confectionery Products

2 Introduction The reaction between sugars and amino groups was first described in 1908 by two Englishmen, Ling & Malting, who considered color formation in beer. In 1912 Louis-Camille Maillard described a browning reaction between reducing sugars and amino groups. Despite not being the first to report the reaction, Maillard was the first to realize the significance of the reaction in areas as diverse as plant pathology, geology and medicine. It is interesting to note that despite there having been six international symposium on the Maillard reaction, not one of the papers was a direct study on the Labuza et al., 1994). In fact, it seems that recent symposia were as much concerned with the medical aspects as food chemistry of the Maillard reaction. The medical world has begun to realize that there may be a role for the Maillard reaction in the formation of complications of diabetes and aging, in which the blood glucose becomes bound to proteins in the body in a similar way to food proteins and glucose. Despite the lack of direct research on the Maillard reaction in confectionery, it can be seen that the Maillard reaction will play an important role in the formation of flavors and colors of some confectionery products since the main Maillard reactants are present. This paper is particularly concerned with the Maillard reaction in non-chocolate confectionery. The Maillard reaction is one of four nonenzymatic browning reactions which occur in food. The other three are: 1) the degradation of ascorbic acid, 2) lipid peroxidation 3) sugar-sugar caramelization. The chemistry of these reactions is related to the Maillard reaction. Ascorbic acid (AsA) undergoes a reaction chemically similar to that of sugars except that amino acids are not necessary for browning. Since AsA is very reactive, it degrades by two pathways, both of which lead to the formation of dicarbonyl intermediates and subsequently to form browning compounds (Davies & Wedzicha, 1992). Lipid peroxidation occurs by the action of oxygen and reactive oxygen species on the fatty acids, especially unsaturated fatty acids. These are oxidized to form aldehydes 3 and ketones which then react with amino acids to form brown pigments, as in the Maillard reaction. It is possible that peroxidation products induce the browning reaction of the Amadori products (Hermosin et al., 1992). At high temperatures (> 80 o C) sugar-sugar interactions or the caramelization reaction occurs. This is a complex series of …