The Preparation Of Different Smoking Liquids And Their Effects On The Quality Characteristics Of Dried Fish

In this paper,fragrant pear wood,red willow twigs,and walnut shells are used as raw materials to prepare smoking liquid.Based on GC-IMS,the difference analysis of volatile flavor compounds in different smoking liquids and their physical and chemical properties are analyzed and identified;grass carp is used as raw material to make air-dried Fish,and studied the smoking technology of air-dried fish;three different smoking liquids were applied to air-dried fish,and the effects of different smoking liquids on the flavor characteristics and storage characteristics of air-dried fish were studied,and the following conclusions were summarized:1.The optimal parameter combination is dry distillation temperature 402.22℃,dry distillation time75.66 min,wood thi CKness 0.627 cm.Under these conditions,the phenol content of the smoked liquid is10.066 mg/m L,the carbonyl compound content is 14.35 g/100m L,and the yield is 33.082%,which is basically consistent with the predicted value.The L^*value of the smoking liquid decreases with the increase of the retorting temperature.The b^*,C^*_aband h^°_abvalues change with the increase of the retorting temperature.The trend is similar to the L^*value,but the change trend of the a^*value is opposite to the L^*value.With the increase of retorting temperature,the total color of red willow twig smoked liquid changes from light yellow to brown.When the dry distillation temperature is 380℃,it is closest to the color of commercial smoking liquid.perforated resin and walnut shell adsorption and refining have no effect on the p H value of the smoke liquid,but slightly reduce the phenol and carbonyl compound content and yield of the smoke liquid,and reduce the pollution of carcinogens such as 3,4-benzopyrene.2.The yellowness value（b^*）of red willow smoke liquid is higher than that of pear wood smoke liquid and walnut shell smoke liquid.The lightness value（L^*）of pear wood smoked liquid is higher than that of red willow twig smoked liquid and walnut shell smoked liquid.The redness value（a^*）of walnut shell smoking liquid is the largest.Fragrant pear smoked liquid has brighter color and better appearance quality,which is the closest to commercial smoked liquid;the phenol content in smoked liquid is the most in red willow twig smoked liquid,followed by walnut shell smoked liquid and Fragrant pear smoked liquid The least in the liquid.The carbonylation content in the smoked liquid was walnut shell smoked liquid>red willow twig smoked liquid>pear wood smoked liquid.All three kinds of smoke liquids have 3,4-benzo,and the content is the most in walnut shell smoke liquid,while red willow twig smoke liquid and pear wood smoke liquid have less content.The p H values of the three kinds of smoke liquids are:pear wood smoke liquid>Red willow branch smoke liquid>Walnut shell smoke liquid;the volatile organic compounds in the smoke liquid mainly include phenols,aldehydes,ketones,alcohols and Esters,etc;the types of volatile organic compounds in the three smoking liquids are roughly the same,but the content is obviously different;the three smoking liquids can be well grouped into three categories,and the red willow twig smoked liquid and the other two samples The difference is even greater,and the samples of fragrant pear wood smoke liquid and walnut shell smoke liquid are relatively more similar.3.With the extension of air-drying time,the p H value of air-dried fish showed a downward trend and then an upward trend.The water content,water retention rate,and water activity showed a downward trend,while the volatile base nitrogen,sodium chloride content and tenderness increased.The color parameter brightness value（L^*）shows a decreasing trend,while the redness value（a^*）,yellowness value（b^*）,and total color difference value（△E）show a gradual increase trend;The best combination of parameters is that the concentration ratio of smoking liquid is 6:4,the smoking time is 106.37 min,and the smoking temperature is 91.214℃.Under this predicted condition,the sensory score of the smoked air-dried fish is88.085 points and the water absorption rate is 5.775%,which is basically the same as the predicted value.Consistent;the volatile organic compounds in air-dried fish（CK）mainly include aldehydes,alkenals,alcohols and ketones,etc.The volatile organic compounds in smoked air-dried fish mainly include phenols,esters and ketones,etc.,air-dried There is a big gap between the composition of volatile organic compounds in fish（CK）and smoked air-dried fish.The content of a large number of substances in air-dried fish（CK）is much higher than that in smoked air-dried fish,and the volatile organic compounds in three kinds of smoked air-dried fish There are also big differences.The flavor of air-dried fish before and after smoking has changed a lot.Compared with the three methods of smoking,the flavor of the pear wood smoked fish is much different from the other two smoked fish.4.The presence of phenols,carbonyl groups and organic acids in the smoked liquid has an inhibitory effect on the growth and reproduction of microorganisms.The antibacterial effect of the smoked liquid is different in different smoked air-dried fish.Smoke liquid can prolong the storage period of smoked air-dried fish under the antibacterial effect,and ensure the safety of eating;under the anti-oxidation and antibacterial effect of smoke liquid,the slow L^*value decreases with storage time,preventing short-term fish color and sensory quality Reduce and extend the shelf life of smoked air-dried fish;no harmful substances such as benzo（a）pyrene have been detected in the three types of smoked air-dried fish,ensuring safety.