Study On Drying Technology Of Red Acid Soup And Quality Of Cooking Meat Food

Acid soup,as the cultural crystallization of traditional acidic food of Miao and Dong nationalities in Guizhou,is not only rich in nutrients,but also has the functions,such as seasoning,coloring,flavoring,deodorizing,degreasing,appetizing and spleen-enhancing,and appetite enhancement and so on.Acid soup is rich bioactive substances,and has multiple effects,such as anti-fatigue,anti-aging,regulating body immunity,and improving cardiovascular disease.Red acid soup,naturally made from tomatoes and pepper,is known as the three hotpot condiments in China.It is widely used in cooking acid soup fish,acid soup beef,acid soup pork trotter and other characteristic flavor food,which has been accepted by consumers.However,at present,the production of red acid soup has been still a traditional fermentation process.The product of acid soup in the market has been packaged in plastic bags or bottles,which are not convenient to carry and have high transportation costs.There have been also hidden dangers of excessive additives and migration of harmful substances in acid soup.The flavor of different brand products is quite different,and the quality deterioration is prone to occur in the process of transportation and marketing because of the non-standard enterprise quality management and the imperfect standard system.Therefore,the the physicochemical indexes and flavor characteristics of red acid soup of five commercially-available mainstream brands were first analyzed to obtain a high-quality red acid soup(FR)as a test material.Then,the quality difference of dried red acid soup powder(DFR)treated by vacuum microwave and vacuum freeze drying methods was discussed.Meanwhile,the nutritional quality of broth and texture characteristics of muscle cooked by FR and DFR were evaluated,which provide a scientific basis for developing the natural red acid soup powder without additives and its flavor food.(1)The physicochemical indexes and flavor characteristics of red acid soup from commercially available mainstream brands were analyzed,and the results showed: the organic acid of 5 red acid soup samples had the highest lactic acid content(5.07~11.50 g/kg),and the content of total free amino acid ranged from 160.04~330.10 mg/100 g.Red acid soup was rich in polyphenols and flavonoids(59.52~75.55 mg GAE /g and 14.31 ~ 25.65 mg RE / g,respectively)as well as capsaicin,dihydrocapsaicin,lycopene(4.05~12.91,0.97~3.11 and 9.56~13.05 mg/g,respectively).The acid taste was the highest in electronic tongue signal response value,followed by bitter and salty taste.The contents of umami and sweet amino acids in red acid soup were high,which mainly were glutamic acid and alanine,respectively.Electronic nose and PCA analysis showed that the volatile flavor of red acid soup was dominated by alcohols,acids and esters,and the aroma components of the three kinds of red acid soup G1,M1 and L1 were similar.(2)The effects of drying methods on the quality of DFR showed that the retentions of basic nutrients in DFR treated by vacuum freeze-drying were higher than that treated by vacuum microwave drying,but the retention rates of polyphenols and flavonoids were lower than vacuum microwave drying(8.88% and 5.73%,respectively).The powder dried by vacuum freeze-drying method had higher moisture content and hygroscopicity,and worse fluidity.Using maltodextrin(MD)as the adsorption carrier of red acid soup,the higher the additive amount(10%~40%)was,the lower the moisture content and hygroscopicity of DFR powder had,the better the powder yield,solubility and fluidity were.However,the nutrient content of DRF was reduced and the color difference value of powder increased as the additive amount increased.Comprehensively considering the product quality and economic benefits,the additive amount of MD was 20 ~ 30%.(3)Compared with pure water(PW)cooked broth,the types and contents of total free amino acid in fish soup,beef soup and pork trotters soup cooked by FR and DFR increased significantly.The content of essential amino acids in fish soup cooked by FR and DFR increased by 96.46 and69.19 mg/100 g,respectively,and the sweet amino acids,mainly including alanine and proline,increased significantly.The content of total volatile flavor substances in fish soup cooked by FR and DFR were 3.65 and 1.85 times that of PW cooked fish soup,respectively,and the contents of aldehydes,acids and esters in FR cooking fish soup increases significantly.Electronic nose and PCA analysis showed that the aroma components of PW and DFR cooking fish soup were close,while the aroma components of FR cooking fish soup were unique.The content of essential amino acids in PW and DFR cooking beef soup increased by 137.78 and 94.69 mg/100 g,respectively,and the content of sweet amino acids increased significantly,with proline increasing the most,followed by alanine.The contents of total volatile flavor substances in PW and DFR cooking beef soup were 7.33 and3.32 times that cooked by PW,and the content of aldehydes,alkenes and acids increased significantly.Electronic nose and PCA analysis showed that the flavor components of FR and DFRcooking beef soup were similar and obviously different from PW cooking beef soup.The content of calcium in PW and DFR cooking pork trotters soup increased by 21.92 and 5.92 times,and the content of essential amino acids increased by 223.99 and 109.19 mg/100 g,respectively.The content of umami and sweet amino acids increased significantly,mainly glutamic acid,alanine and proline.The contents of total volatile flavor substances were 3.13 times and 3.67 times that of PW cooking pork trotter soup,respectively,and the content of aldehydes increased significantly.Electronic nose and PCA analysis showed that the aroma components of FR and DFR cooking pork trotter soup were similar.(4)The effect of cooking methods on the physical properties of cooking meat showed that the weight loss rate of fish,beef and trotters cooked with FR was the highest,and the weight loss rate of samples cooked by PW was the lowest.Compared to cooking with PW,the L* of pork trotters cooked with FR and DFR decreased obviously,but the values of a* and b* increased.The L* value of beef cooked with FR and DFR decreased slightly,and there was no significant difference between the values of a* and b*(p>0.05).Fish cooked with FR had better color(L*,b* values were the largest,a* value was the smallest),while fish cooked with DFR had no significant color change(p>0.05).The hardness,chewability,elasticity,cohesion and stickiness of fish and beef cooked with FR and DFR were higher than that cooked with PW cooking.However,only the cohesion of pork trotters cooked with FR and DFR had increased compared with that cooked with PW,while the hardness,chewability,elasticity and stickiness decreased.