Effects Of Edible Coatings On Quality And Relative Physiological Characteristics In Fresh-cut Peach

Effects of three kinds of edible coatings(carrageenan,carboxymethyl cellulose,sodium alginate)and their mixtures in two of them on quality and related physiological parameters in fresh-cut peaches at 0 and 5℃were investigated. Scanning electron microscopy was also used to investigate the microstructures of the coatings.The physical characters of the coatings, including mechanical and water permeability studied as well. The main results were as follows:1 At 0 and 5℃, the coating with sodium alginate delayed the decline of Hunter L and the increase of Hunter a or b, as well as inhibited activities of polyphenoloxidase (PPO), maintained total phenol contents and decreased browning degree, and maintained the texture and titratable acid content in fresh-cut peaches. At 5℃,the carrageenan coating inhibited activities of polyphenoloxidase (PPO), maintained total phenol contents and decreased browning degree. At 0℃, the coatings of carrageenan and CMC decreased browning degree, retarded the decline of titratable acid content and texture, or the increasing of soluble solids content. The microorganisms were well inhibited by the coatings in fresh-cut peach.2 The conbined coatings reduced the decline of Hunter L and the increase of Hunter a or b as well, especially in the inhibitions of PPO activity or browning degree. The mixtured coating in carrageenan and CMC showed the best among them.3 The coatings made from carrageenan showed the best in terms of mechanical property and diaphaneity, as well lower water vapor permeability, Followed was sodium alginate. There are not obviously difference on vapor permeability between carrageenan and sodium alginate. The mixtured coatings were improved on mechanical property and water permeability. Scanning electron microscopy showed that the microstructures of carrageenan coatings was uniform and compact.