Study On Techniques Of Flaworing Based On Maillard Reaction And Comparison Of Flavor With Related Products

Silver carp meat is tender, nutritious and high in protein. It is one of the freshwater fish which is growing fast in output in China. However, because of the specific thick smell of silver carp and being spiny, the processing of silver carp are restricted by which its flavor is worse than other freshwater fish. Therefore, in this thesis, low-value silver carp as raw materials was used to produce two flavorings based on Maillard Reaction to enrich the types of spices in the current market, another is to find a reasonable evaluation method of flavor analysis through comparison of flavor with commercially related products and to provide basic experimental datum for characteristics aroma of the spices.In this paper, first of all, the basic components of silver carp were determined for the feasibility of developing flavorings as raw materials; the optimum parameters of hydrolysis were discussed, and by adding sugar, VB1 and some amino acids to hydrolyzate, two kinds of flavoring base(I)and(II) were produced based on Maillard reaction; Flavor compositions and volatile components of two kinds of flavoring base were analyzed and were compared with the commercially related products to know about the differences between taste and flavor; using the fragrance value method, the characteristic aroma of two kinds of flavoring base was determined for market position. The results were as follows:(1) Taking silver carp as raw material, hydrolysis was carried on by complexing flavorzyme with protamex(3:1), the degree of hydrolysis alone with sensory evaluation as indicators, through the response surface method, the optimum parameters of hydrolysis processing were obtained:time 7.Oh, temperature 55℃, pH 7.7, quantity of enzyme 2.4%, the maximum degree of hydrolysis was 54.18%under the optimum hydrolysis conditions. The prepared hydrolyzate had a normal color and faint smell of fish, no obvious bitterness. So it could be used as a raw material for preparing flavoring based on Maillard Reaction.(2) By single-factor experiments and optimization of multi-factor orthogonal experiments, with sensory evaluation as an indicator, the proportions and conditions of flavoring base(I) were determined. The best ratio of additives in Maillard reaction and the suitable reaction conditions were as follows:glucose 5%, NaCL 5%, VB1 0.25%, reaction temperature of 115℃, reaction time of 60 min, pH 7.5. The flavoring base(I) had dark yellow colour with rich butter flavor.To exploit flavoring base(II), adding four kinds of amino acids to the flavoring base(I), the best ratio of additives and optimum reaction conditions in flavoring base(II) were as follows:glutamic acid 1%, proline 2%, arginine 1%, aspartic acid 0.4%, glucose 5%, NaCL 5%, VB1 0.25%, reaction temperature of 115℃, reaction time of 60 min, pH 7.5. The flavoring base(II) had reddish-brown colour with rich seafood flavor.(3) The compositions and contents of organic acids, nucleosides as well as free amino acids in two kinds of flavoring base were analyzed, and the measured results show that:Organic acid composition:flavoring base(I) contained more tartaric acid, citric acid, succinic acid and lactic acid, while flavoring base(II) had more tartaric acid, lactic acid, malic acid and succinic acid, as well as a small amount of pyroglutamic acid, and tartaric acid and lactic acid were measured in related products, besides, malic acid and citric acid were measured in seafood flavor.Nucleosides composition:some amount of GMP and a small amount of hypoxanthine were detected in flavoring base(I), IMP was not detected in flavoring base(I), some amount of GMP and a small amount of hypoxanthine and IMP were detected in flavoring base(II); some amount of GMP and IMP were detected in commercially related products, besides, some amount of hypoxanthine were detected in the seafood flavor.Free amino acid composition:in comparison with hydrolyzate, part of the bitter taste of amino acids in flavoring base(I)such as Cystine, Arginine, Histidine, Lysine, Methionine, Phenylalanine, Isoleucine, Leucine and Tyrosine have much larger reduction with the Maillard reaction carring out. Four added amino acids in flavoring base(II) played an important role, on the one hand they increased the products'flavor and sweetness, on the other hand, the contents of four added amino acids reduced which involved in the Maillard reaction and they might generate many ingredients for contributing to the overall smell.(4) By analyzing volatile components in two kinds of flavoring base, the results showed that:in flavoring base(I), high contents of components were: 4-Methyl-5-thiazole ethanol, Benzaldehyde, Furfural, 1-Octen-3-ol, Nonanal, 2,5-Dimethy pyrazine,3,5-Octadien-2-one and Hexanal. In flavoring base(II), high contents of components were:4-Methyl-5-thiazole ethanol,3-Methyl butanal, 2-Pentyl furan, Methyl pyrazine, Nonanal, 1-Octene-3-ol, Furfural,3-Furan methanol. In chicken flavor and beef flavor, high contents of components were Furfuryl sulfide and 2-Acetyl pyrazine and other sulfur-containing, nitrogen-containing compounds. In pork flavor and mutton flavor, high contents of components were ketones and esters. In seafood flavor, high contents of components were:2-Methoxy-3-methyl pyrazine,2-Pentyl-furan, Disulfide dimethyl with nitrogen-containing, oxygen-containing and sulfur-containing compounds.(5) Through analyzing characteristic aroma in two kinds of flavoring base, the results showed that:the main characteristic aroma components in flavoring base(I) were:3,5-Octadien-2-one, 1-Octen-3-ol, Nonanal, Pentanoic acid ethyl ester, 2-Pentyl-2-nonanal, (E)-2-Octenal,3-Ethyl-2,5-dimethyl pyrazine, Hexanal and 2-Pentyl furan. The main characteristic aroma components in flavoring base(II) were:3,5-Octadien-2-one, Dimethyl trisulfide, 1-Octen-3-ol, 2,5-Dimethyl-4-hydroxy-3(2H)furanone, Nonanal,2-Pentyl furan, 2-Ethyl-3,5-dimethyl pyrazine, Methyl pyrazine, d-Limonene. The characteristics aroma of five related products were analysed, and the main characteristic aroma components in chicken flavor were:(E,E)-2,4-Decadienal, 3-(Methylthio)-1-propanol and other aldehydes. The main characteristic aroma components in beef flavor were:Furfuryl sulfide,2-[(methylthio)methyl]furan and other sulfur-containing, oxygen-containing compounds. The main characteristic aroma components in pork flavor were:2,5-Dimethyl-4-hydroxy-3(2H)-furanone, 2-Acetyl pyrazine and ketones and heterocyclic. The main characteristic aroma components in mutton flavor were:Hexanoic acid ethyl ester, Heptanoic acid ethyl ester and other ester compounds. The main characteristic aroma components in mutton flavor were:Bis(2-furfuryl)disulfide,3-ethyl-2,5-dimethyl pyrazine and other sulfur-containing, nitrogen-containing compounds, which contribute to the seafood flavor 3,5-Octadien-2-one, Dimethyl sulfide, 1-Octen-3-ol,2-Pentyl furan, 3-Methyl butanal and more pyrazine compounds in the flavor of flavoring base (Ⅱ) were also detected.Using the cluster analysis and aroma value method to study flavor components and to compare with commercially related products, the results showed that:flavoring base(I) has a certain degree of difference from commercially related products, but there are sensory rich in butter flavor and burnt aroma, so it can be developed into sauce flavor spices, while flavoring base (II) is closer to the seafood flavor, so it can be developed into seafood flavor.