Study On The Process Of Deodorization And Debitterization Of Enzymatic Hydrolysate Of Tilapia For Flavoring Seasoning

Tilapia fillets are by-product of processing exports,about 2/3 of the entire fish,and 15% of the protein can be prepared into umami-tasting substances using bio-enzymatic technology.It has solved the issue that tilapia fillets are only used as low value-added products such as processing feeds and discarded problems that cause environmental pollution,and at the same time enrich the flavoring spice market.The screened salt-tolerant enzymes are used to prepare enzymatic hydrolysates to solve the problem of strong bitterness in the traditional enzymatic hydrolysates,combined with the Maillard reaction to enhance fragrance and flavor technology to achieve different flavoring bases.The main findings are as follows:(1)Optimization of Enzymatic Hydrolysis Conditions for Tilapia Strips From the single factor experiment of alkaline protease,papain and trypsin,papain was selected as the best enzyme.The optimization of papain orthogonal experiment showed that the amount of added enzyme was 0.4%,the temperature was 55°C,and the ratio of solid to liquid was 1:2.The best degree of hydrolysis was obtained in the case of 4 h;the salt-tolerant complex enzyme screened from fish sauce had protease activity and lipase activity at a certain salinity,and the response surface optimization of salt-tolerant complex enzyme showed that the enzyme solution was sensory.The highest score,the best enzymatic effect.The best hydrolyzed solution was prepared under the condition of 6% of salt content,0.4% of enzyme,1:2 ratio of solid to liquid,temperature of 55°C,and 4 hours without pH adjustment.(2)Enzymolysis solution dislocation technology Hydrolysis of tilapia fillets under the above optimized conditions using salt-tolerant enzyme complex resulted in a good deodorizing effect.The total sensory score was 6.42,and the total amino acid content was 177.634 mg/mL,including leucine(25.791 mg)./mL),isoleucine(2.838 mg/mL)was slightly bitter,accounting for 16.11%,glutamic acid(4.871 mg/mL),taurine(18.817 mg/mL),and glycine(14.513 mg/mL).The total content of amino acids with a sweet taste of alanine(11.075 mg/mL)accounted for 52.44%.The volatile flavor data measured with solid-phase headspace microextraction-gas chromatography(SPME-GCMS)showed that ketones The proportion of aldehydes,alcohols and olefins accounted for 64.3%.(3)Enzymatic Hydrolysate and Freshening Technology Selecting the hydrolysis solution of salt-tolerant complex enzyme with different degree of hydrolysis as the base liquid to perform the Maillard reaction of reducing sugars to increase the fresh fragrance.The results of amino acid analysis and SPME-GCMS analysis of the Maillard reaction product indicated that the total amino acid content was 273.391 mg/g,and the amino acid with a sweet taste accounted for 64.47%,of which glutamic acid(11.202 mg/mL)and alanine(16.030 mg/mL),proline(2.056 mg/mL),aspartic acid(2.697 mg/mL),glycine(17.786 mg/mL),taurine(22.083 mg/mL),etc.Ketones,aldehydes,alcohols and olefins accounted for 70.9% of the volatile flavor substances.28% of the hydrolysis solution was added with 1% xylose and reacted at 110°C for 60 min to prepare a base material with a flavor and flavor;28% of the hydrolysis solution was added with 2% glucose at 110°C.After 60 min of reaction,a base material with a fruity,chestnut-like aroma can be prepared.(4)Study on the key groups of taste of Maillard reaction products Fourier transform infrared spectroscopy results show that the enzymatic hydrolysate and the corresponding Maillard reaction product have C-H stretching vibration peaks of olefinic double bonds near the wavelength of 3014 cm-1,indicating that they are rich in acids.In the xylose system,the O-H,C-H,and C=O groups before and after the reaction increased by 23%,35%,and 56%,indicating that the content of alcohols,ketones,and other substances in the product increased.The use of salt-tolerant complex enzymes screened in traditional seasoning fish sauce hydrolyzes tilapia fillets to solve the problem of strong odor and heavy bitterness of traditional protease hydrolysates.Compared with the cooking liquid of tilapia,it is resistant to salt.The complex enzyme enzyme solution retains the umami taste of fish soup.Combining Maillard reaction technology with different types of reducing sugars can produce flavoring bases of different flavors,can be used to make liquid,paste,powdery bases,and also can be used as some hot pot soup bases to enrich the seasoning market.