| Sargassum pallidum belongs to Phaeophyta sargassaceae and are extensively distributed in ChinaYellow Sea and Bohai Sea.Due to no being edible,S.pallidum is used in relatively narrow scope at present,and ouly a small part is used as feed,aigin and raw materials of pharmaceutical industry,and most of them has not yet been fully utilized.Some papers report that alga glycine is a kind of miscellaneous polysaccharide.It has a variety of physiological functions,and is an important bioactive substance in brown alga.in this paper S.pallidum collected from Rongcheng in Shandong Province was studied,including extraction of polysaccharides from S.Pallidum and the application of it.1.Research on extraction condition of sargassum pallidum polysaccharidesTemperature,time and ratio of alcohol to raw liquid were selected in single-factor experiment.Based on the single-factor experiment,the extraction parameters were optimized by using three-factor-three-level Box-Behnken Design(BBD).Then the data was analyzed by Design-Expert Software,integrating actual operability,the optimum extraction parameters were obtained as follows:extracting temperature 80 °C,extracting time 8 hours,ratio of water to raw liquid3:1 v/v.Under optimum extraction conditions,the real extraction yield of sargassum pallidum polysaccharides was 11.72 ±3.75%,consistent with the predicted values.2.Research on the preparation of sargassum pallidum polysaccharides composite filmPolysaccharides,glycerol and gelatin were selected in single-factor experiment.Based on the single-factor experiment,the extraction parameters were optimized by using three-factor-three-level Box-Behnken Design(BBD).Then the data was analyzed by Design-Expert Software,integrating actual operability,the optimum film parameters were obtained as follows:polysaccharides 1.5%,glycerol 2.0%,gelatin 3.5%.Under optimum film conditions,the real tensile strength of sargassum pallidum polysaccharides composite film was 13.67± 2.17 Kpa,the real water solubility of sargassum pallidum polysaccharides composite film was 55.43±3.26%,consistent with the predicted values.3.Research on the features and application of polysaccharides composite filmUsing scanning electron microscope(SEM)to observe the surface and section morphology of polysaccharide composite film which was made under the optimum ratio.We found that film surface smooth and dense,but there are some solid particles at surface at high magnification,We also found that the section of film had holes at surface at high magnification,explaining the weak of intermolecular forces.Stored the polysaccharide composite film at room temperature and 4?,record the thickness,tensile strength,water soluble,permeable rate changes of the film go along with time.We found that stored at 4°C the film thickness decreased slowly than that Stored at room temperature and the thickness of film is stable.And the tensile strength of polysaccharide composite film fell slightly and gradually stabilized,and the tensile strength is greater than at room temperature,So conclusion is that the polysaccharide composite film was stored at 4°C is better than at room temperature.Polysaccharide composite film used as cover film for strawberries and observe the quality such as weightlessness rate,decay rate,pH value,total soluble solids,microbial colony,sensory quality of strawberries go along with time,the results show that,polysaccharide composite film for pallet packing method can restrain rotting rate and the total number of microbe colonies effectively,but in controlling the water loss and sensory were not ideal,due to alga of polysaccharide composite film has bacteriostatic,the oxygen resistance,oxidation resistance,etc.So it's packaging effect could compared with traditional packing in inhibiting microbial,the polysaccharide composite film for strawberries packing had certain feasibility,but the polysaccharide is easy to dissolve in water,it's packaging effect couldn't compared with traditional packing.So we should make a series of optimization and improvement on the polysaccharide composite film to applied to food packaging. |
PDF Full Text Request