Preparation Of Antioxidant And Antimicrobial Food Packaging Paper With High Barrier

This topic chosen botanical active ingredients as antibacterial and antioxidant agents, impregnated or coated it on base paper to preparation natural antioxidant and antibacterial packaging paper, which can meets green and safety requirements of food market.Tea and magnolia botanical selected for the experimental, ultrasound-assisted extraction method used for extracting the active ingredients in plants, and then antioxidant and antibacterial properties of active ingredients to be tested. It was found that, under the extraction conditions that solid-liquid ratio 1:10, ethanol concentration 75%, ultrasonic time 30min, ultrasonic temperature 70℃, the tea extract has maximum inhibition zone diameter on the tested bacteria (Staphylococcus aureus, Escherichia coli, Salmonella and Bacillus subtilis). At this point, the minimum inhibitory concentration of tea extract is 25μL/mL and the amount of half remove of DPPH radical (IC50) is 2.203 μL/mL. Under the extraction conditions that solid-liquid ratio 1:10, ethanol concentration 90%, ultrasonic time 40min, ultrasonic temperature 65℃, the magnolia extract has maximum inhibition zone diameter on the tested bacteria. At this point, the minimum inhibitory concentration of magnolia extract is 8.125μL/mL and the IC50 is 15.477μL/mL. The antibacterial properties of magnolia extract is weak than tea extract, and both of them have high DPPH scavenging rate than commercial food preservative TBHQ.Analysis the extract component with HPLC, experiments showed that tea extract active ingredients is polyphenols, whose main ingredient is catechins, and its monomers including epicatechin (EC), epigallocatechin (GC), epigallocatechin (EGC), epicatechin gallate (ECG) and epigallocatechin gallate (EGCG); The active ingredients of magnolia extract is magnolol and honokiol. Folin method using for extract quantitative analysis, by gallic acid regression curve can calculate tea polyphenols extraction rate is 11.9%, and magnolia total phenol extraction rate is 47.4%.By increasing the degree of beating to improve the mechanical properties and barrier properties of the paper, the quantitatively of experimental paper is 56.60g/m, burst index is 5.45kPa · m2/g, average tensile index is 161.13N · m/g and the air permeability is 2.65 × 10-4μm/Pa · s, which meets the national standard requirements for food packaging.With the method of impregnation or surface coating,20% PVA complex with magnolia extract to process paper and packaging for cheese. Under the same storage conditions, compare the quality of cheese packaged with base paper, impregnated coated paper and coated paper. Experimental results showed, the best packaging for cheese is extract/PVA coated paper, predicts its shelf life using kinetic equation is 136 days.