title: Using Liquid Smoke to Improve Mechanical and Water Resistance Properties of Gelatin Films.
abstract: Improvement of mechanical and water barrier properties is critical for gelatin films when applied to edible food packaging. A liquid smoke (LS) obtained from hawthorn nucleus was used to improve the performance of gelatin film based on its abundant compounds. Through SPME-GC-MS analysis, 86 volatile and semi-volatile chemical compounds was detected in LS, in which the total carbonyl compounds were 27.60%, with the main aldehyde as 2-furaldehyde (9.83%). For gelatin films, an observable influence of LS on film transparency was observed in gelatin films, but not for its thickness and microstructure. Desirably, adding LS into gelatin solution increased the tensile strength of the films, with a better value of 16.38 MPa as 3 wt% LS added, compared with the control (10.30 MPa). Accordingly, film elongation decreased with a LS dependent manner. Furthermore, the water resistance properties of gelatin film were improved by the LS addition, which was supported by the results of water contact angle, water vapor permeability. Moreover, the addition of LS also led to a higher insolubility for gelatin films. Also, thermal stability of the LS treated gelatin films was slightly enhanced with the DSC analysis. According to the FTIR spectra and crosslinking degree detection results, all the above enhancing of gelatin film should be attributed to the crosslinking between carbonyl groups in LS and amide functionalities in gelatin based on nucleophilic reaction.
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Univ. of Science and Technology, Tianjin, 300457, China.|Limerick Pulp and Paper Centre, Univ. of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada.
authors.forename: Wenwang
authors.initials: W
authors.lastname: Wang
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Univ. of Science and Technology, Tianjin, 300457, China.
authors.forename: Cong
authors.initials: C
authors.lastname: Li
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Univ. of Science and Technology, Tianjin, 300457, China.|Limerick Pulp and Paper Centre, Univ. of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada.
authors.forename: Hongjie
authors.initials: H
authors.lastname: Zhang
authors.affiliation: Key Laboratory of Food Nutrition and Safety, Ministry of Education, Tianjin Univ. of Science and Technology, Tianjin, 300457, China.|Limerick Pulp and Paper Centre, Univ. of New Brunswick, Fredericton, New Brunswick, E3B 5A3, Canada.
authors.forename: Yonghao
authors.initials: Y
authors.lastname: Ni
mesh_terms: D018857:Food Packaging; D005780:Gelatin / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D010539:Permeability; D012906:Smoke; D012996:Solutions; D013227:Steam; D013718:Tensile Strength; D014867:Water / Q000737:chemistry*; D014934:Wood / Q000737:chemistry
chemical_list: D012906:Smoke; D012996:Solutions; D013227:Steam; C015233:gelatin film; D014867:Water; D005780:Gelatin
keywords: crosslinking; mechanical properties; protein films; smoking flavor; water barrier