Amino compounds with sugar

Hough, L., Jones, J. K. N. and Richards, E. J. 1953. The reaction of amino-compounds with sugars. Part II. The action of ammonia on glucose, maltose and lactose. J. Chem. Soc. 2005-2009. 

The Reaction of Amino-compounds with Sugars. Part I. The Action of Ammonia on D-Glucose, L. Hough, J. K. N. Jones, and E. L. Richards,/. Chem. Soc., (1952) 3854-3857. 

A common thread that can link the ammonium and peptone catalyst poisoning results just described could be the Maillard reactions of amino acids with sugars (5). Recent studies have shown that the ammonium ion is highly reactive, more so than substituted versions (6). Its use as ammonium bicarbonate in developing flavoring compounds by Maillard reactions in extrusion cookers has been reported (7). It is likely that such reactions could occur at our processing conditions. We can speculate that such products could have acted as catalyst surface poisons, which might have been subsequently washed from the catalyst, before it was reused in its active form. 

The aroma precursors have been selected by taking into account the significant role of the Maillard reaction. Indeed, most aroma compounds of this type are formed by the reaction of amino acids with sugars or their degradation products. So we have obtained roast beef, roast mutton and heated vegetable aromas after having treated a mixture of amino acids and glucose at different temperatures and for varied times. 

Cysteine is an important precursor of meat flavor and is therefore often being used in precursor systems for the industrial production of meat process flavorings (1-4). Meat flavor development in these systems is usually based on the Maillard reaction of cysteine (and other amino acids) with sugars. Unfortunately, there are a few complications that prevent that high yields of volatile flavor compounds are obtained from these reactions. The first... 

The reaction of amino acids with sugars to form Schiff s base-type compounds has been often suggested to be a feasible process in the formation of coloured condensed material in seawater, particular in the presence of clay minerals (Hedges, 1978). It is also worthy to note that natural free sugars and amino acids when heated in seawater form fluorescent compounds whose excitation and emission maxima correspond with those formed on reaction of amines with aldehydes (Honda et al., 1974). These experiments were performed at high temperatures (G. Liebezeit, R. Dawson and K. Mopper, unpublished results) and there is some suggestion that the apparent disappearance of amino acids on standing in seawater at room temperature, may be connected in part to this abiotic process. 

Chemical Interactions of Amino Compounds and Sugars. V. Comparative Studies with D-Xylose and 2-Furaldehyde, Tzi-Lieh Tan, M. L. Wolfrom, and A. W. Langer, Jr., /. Amer. Chem. Soc., 72, 5090-5095 (1950). 

The natural moisture of the cocoa bean combined with the heat of roasting cause many chemical reactions other than flavor changes. Some of these reactions remove unpleasant volatile acids and astringent compounds, partially break down sugars, modify tannins and other nonvolatile compounds with a reduction in bitterness, and convert proteins to amino acids that react with sugars to form flavor compounds, particularly pyrazines (4). To date, over 300 different compounds, many of them formed during roasting, have been identified in the chocolate flavor (5). 

Compounds with a phosphonate group linked by a P-C bond to a carbohydrate residue may be named as glycos-n-ylphosphonates (cf. 2-Carb-31.2) or as C-sub-stituted carbohydrates (cf. amino sugars, 2-Carb-14). 

Studies on the bitterness of other compoundsdo not, however, support this model. The bitter amino acids and sugars, for example, do not possess an AH,B unit of this dimension. As already mentioned, there is some evidence suggesting that there is more than one type of bitter-taste quality and receptor. If this is the case the diterpenes probably interact with a receptor showing a steric requirement difierent from that involved with the other classes of compounds. 

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