Study On Quality And In Vitro Digestion Of NFC Apple Pear Mulberry Juice Treated By Ultra High Pressure

In this study,the NFC apple-pear mulberry juice developed using apple-pear and mulberry as raw materials was taken as the research object.The basic formula,storage quality,and simulated gastrointestinal digestion in vitro of ultra-high pressure NFC apple pear mulberry juice were studied.The main research results are as follows:（1）Optimize the basic formula of NFC apple pear mulberry juice.Using the sensory score as an indicator,a single factor experiment was conducted on the amount of mulberry juice,citric acid and white sugar added.After selecting the optimal level of single factor,the L₉（3⁴）orthogonal experiment was optimized to determine the most NFC apple pear mulberry juice.The best basic formula is 11%mulberry juice,0.04%citric acid,6%white sugar and 82.96%apple pear juice.（2）Under the storage condition of 25℃,using pasteurization（95℃,10 min）as a control,explore the physical and chemical indexes,nutritional indexes and antioxidant capacity of ultra-high pressure sterilization（500 MPa,20 min）on NFC apple-pear mulberry juice.And other effects.The results showed that the total phenol,flavonoid and anthocyanin content of the ultra-high pressure treatment group and the pasteurization treatment group decreased by 34.89%,53.51%,52.84%and 39.56%,58.62%,69.08%,and DPPH and ABTS free radical removal the decline in the ability and scavenging ability of hydroxyl radicals were 41.44%,26.84%,33.36%and 49.88%,31.07%,35.23%;the results show that ultra-high pressure treatment more effectively preserves the resistance of fruit juice during storage than pasteurization Oxidized components,and the decline of the antioxidant capacity of the UHP treatment group was smaller than that of the pasteurization treatment group.（3）The headspace solid-phase microextraction method and gas chromatography-mass spectrometry were used to periodically measure and analyze the aroma components of NFC apple-pear mulberry fruit juice,and explore the types and relative content of flavoring substances during storage.Results It is shown that the esters and aldehydes have a greater effect on the aroma components of fruit juice,and their relative contents account for more than 20%of the total content.The volatile substances of pasteurized fruit juice are mainly ester compounds,the relative content of which is as high as 57.28%,but the aroma components evaporate quickly,and the relative content during storage period shows a downward trend.It is mainly aldehyde compounds,the relative content of which is as high as 65.54%,and the aroma components are volatilized slowly,and the relative content shows a trend of first increase and then stability;the alcohol,hydrocarbon and ketone volatile substances of the two do not contribute much to the aroma.（4）Establish an in vitro simulated gastrointestinal digestion model to investigate the change of antioxidant components in the NFC apple-pear mulberry juice after ultra-high pressure sterilization during the in vitro digestion process.The results show that during the gastrointestinal digestion in vitro,the total phenol in the mulberry juice The contents of flavonoids,anthocyanins,and anthocyanins all showed simulated gastric digestion group>gastric acid group>gastric blank group,simulated intestinal fluid group>intestinal blank group;the total phenol and flavonoids in the juice were released,and the contents showed an upward trend,the maximum values were 2568.26±33.79 mg/L and 2317.61±6.67 mg/L,which are 1.75 and 2.16 times the initial stomach values（1468.57±35.74 mg/L and1074.21±34.28 mg/L）;the anthocyanins were degraded and the content showed a downward trend with a minimum value of 142.55±8.54 mg/L,a decrease of60.30%from the initial gastric value（359.03±11.45 mg/L）;in the acidic environment of gastric digestion,total phenol was not released,and the addition of pepsin made a large amount of total phenol Release;the acidic environment of gastric digestion has a certain promotion effect on the release of flavones in the complex juice,while the neutral environment during intestinal digestion has no significant effect on the release of flavonoids;Under the environment,it has shown a more significant decline.