Effect Of Rice Bran Wax Coating On Texture And Polysaccharide Molecule Nanostructure Of Postharvest Fruits And Vegetables

Fruits and vegetables are an important part of our diet and constitute a commerciallysignificant food commodity. On a global basis, there is an ever-increasing demand forimproved texture and high quality in fruit. One of the limiting factors that dictates theeconomic value of fruit crops is the relatively short ripening period and shelf life, leading toadverse effects on storage. Fruit softening and ro are major sources of commercial loss to thefruit-growing industry. It was hypothesized that degradation of cell wall polysaccharides(CWP) was responsible for the decreasing of quality including texture. The purposes of theresearch were to extend the shelf life of fruits by low temperature and coating, and to illustratethe fundamental of CWP evolution.For cherry tomato, both low temperature and coating were effective to delay the decreaseof firmness, titratable acidity and inhibit the increase of total soluble solids content, weightloss and pH. Coating delayed the degradation of pectin of cherry tomato significantly. And thedeclining trend of cherry tomato postharvest quality had been postponed after rice bran waxtreatment. The result will help optimize the coating technology for better maintaining freshfruits. It shows that there was a close relationship between polysaccharide contents,morphology and fruit quality. The dissociation and degradation of main and side chains ofwater-soluble and chelate-soluble pectins were significantly delayed by lowered temperatureand coating. The widths of pectins and hemicellulose that determined by atomic forcemicroscopy (AFM) show that the values were composed of basic units:15.625,19.531,23.438and27.344nm for water-soluble pectin (WSP),15.625,19.531,23.438and31.250nmfor chelate-soluble pectin (CSP),15.625,23.438and31.250nm for sodium carbonate-solublepectin (SSP) molecules. At the late stage of cold storage, CWP polymers disappeared whilelinear single fractions increased. Cherry tomato fruit with coating treatment showed lessfrequency of chains with small widths and lengths than that of control group. It indicates thatcoating delayed the degradation of CWP of cherry fruit. It indicates that the fundamental ofcoating for postharvest cheery was by inhibiting the degradation of CWP. The result will helpoptimize the coating technology for better maintaining fresh fruits and vegetables.