Preparation And Shelf-life Prediction Of Pueraria Montana Solid Beverage

Objective:Pueraria montana（Loureiro）Merrill is a tuberous root of Pueraria montana,rich in flavonoid active substances,and is managed in the List of Articles that are Both Food and Drugs.At present,there are more studies on the application of Pueraria montana in Chinese medicine,but fewer reports in the food processing field,and no research reports or products on its solid beverage have been seen.In this project,a functional Pueraria montana solid drink was developed,and the experiment was carried out in four aspects:extraction process,formulation optimization,quality analysis,and shelf life.Methods:A single-factor test combined with response surface methodology was used to optimize the aqueous extraction process of Pueraria montana;UV spectrophotometry and High Performance Liquid Chromatography were used to characterize the total flavonoids of Pueraria montana;and agar diffusion method and DPPH·,ABTS⁺·and total reducing capacity were used to evaluate the bioactivity of total flavonoids of Pueraria montana.The antioxidant activity changes during the digestion process were simulated in vitro by the combination of response surface methodology and fuzzy sensory evaluation method for the optimization of Pueraria montana solid beverage process.Fourier Transform Infrared Spectroscopy,X ray single crystal diffraction,Scanning Electron Microscope,Thermal Gravity and Differential Scanning Calorimetry were used to characterize Pueraria montana solid beverage.GC-MS,Colorimeter,Electronic Nose and Electronic Tongue techniques were used to evaluate the flavor of Pueraria montana solid beverage;kinetic modeling and Arrhenius equation were used to predict the shelf life of the product after irradiation sterilization.Results:1.The optimized parameters were 1:16（m/V g/m L）,69 min extraction time,3 times extraction,and 7.690%of total flavonoids.The optimized process was used to prepare Pueraria montana extract,from which 9 common flavonoid components were detected,and the total content of the 9flavonoid components accounted for 91.81%of the total flavonoids in the extract.2.Pueraria montana extract showed different antibacterial activities against 11 test strains,and was found to be moderately sensitive to Enterococcus faecalis and Bacillus thuringiensis thuringiensis for the first time,with MIC values of 250 mg/m L and 500mg/m L,respectively.the IC₅₀ values of the extract against DPPH·and ABTS⁺·radicals were 0.617 mg/m L and 0.191 mg/m L,respectively,with strong reducing ability.3.The optimal process formulation of Pueraria montana solid beverage was 3.00 g,6.50 g,0.20 g and 3.00 g for the addition of Pueraria montana extract,sucrose,DL-malic acid andβ-cyclodextrin,respectively;under this conditions,the sensory score was 91.85±0.35,with an error value of 2.69%from the theoretical one.The in vitro simulated gastrointestinal digestion of the solid beverage showed high DPPH·,ABTS⁺·,?OH radical scavenging and total reducing capacity of 92.59%±0.85%,81.26%±3.43%,93.89%±0.20%and 0.564 Abs±0.01 Abs.4.The characterization of Pueraria montana solid beverage showed diffuse diffraction rings.Poor thermal stability and high temperature susceptibility to decomposition and interaction between Pueraria montana extract and excipients existed.Nineteen flavor substances were detected from Pueraria montana solid beverage,mainly long-chain hydrocarbons and esters,with higher content of esters;and richer bitterness,freshness and sweetness.5.The sensory quality and nutritional composition of the Pueraria montana solid beverage treated with 6 k Gy ⁶⁰Co-γirradiation showed a decreasing trend,and the microbial content did not exceed the detection limit.6.The prediction model of the total acid,colony The activation energy E_a of total acid and colony in the prediction model were 3.18*10³ and2.52*10³ KJ/mol,respectively,and the finger front factor k₀ was 0.287 and 0.063KJ/mol.Conclusion:The optimal formula of Pueraria montana total flavonoids has strong antibacterial and antioxidant activities.The optimal formula of Pueraria montana solid beverage is light brown in color,dense in taste,stable and even,and has obvious flavor characteristics.Its physicochemical indexes meet the requirements of GB/T 29602-2013"Solid Beverage"standard,and it has strong antioxidant activity and anti-digestive stability.The shelf life of Pueraria montana solid beverage stored at 25℃can reach 135 days.