Development of active packaging films based on quaternary ammonium chitosan, polyvinyl alcohol and litchi (Litchi chinensis Sonn.) pericarp extract

Abstract

Litchi (Litchi chinensis Sonn.) pericarp contains abundant polyphenols that are suitable materials for developing active packaging films. In this study, 1 wt%, 3 wt% and 5 wt% of litchi pericarp extract (LPE) was added into qua-ternary ammonium chitosan (QAC) and polyvinyl alcohol (PVA) matrix to develop active packaging films. The structural, physical and functional properties of QAC-PVA (QP) films were compared with LPE (QP-LPE films) and without LPE (QP films). Results showed QP film had a heterogenous cross-section whereas QP-LPE films displayed rough and uneven cross-sections. After adding LPE, the N–H, O–H, C–H and C=O stretching bands of QP films shifted due to the formation of intermolecular interactions between LPE and film matrix. LPE made the colorless QP film turned brown. QP-LPE films presented lower ultraviolet–visible light transmittance than QP film. After adding LPE, film thickness increased from 0.091 to 0.103 mm, film water vapor permeability increased from 14.98 × 10−11 to 17.21 × 10−11 g m−1 s−1 Pa−1, film oxygen permeability increased from 0.16 to 0.22 cm3 mm m−2 day−1 atm−1, film tensile strength increased from 14.10 to 17.41 MPa, and film elongation at break decreased from 36.94% to 25.13%. QP-LPE films quickly released polyphenols in distilled water within 4 h and displayed potent antioxidant activity. The antimicrobial ratio of the film against Escherichia coli, Salmonella typhimurium, Staphylococcus aureus and Listeria monocytogenes was elevated from 50.40−68.04% to 58.93−91.38% after adding LPE. Results suggested QP-LPE films could be utilized as antioxidant and antimicrobial packaging materials in food industry.

Antioxidant-Incorporated Poly(vinyl alcohol) Coating: Preparation, Characterization, and Influence on Ripening of Green Bananas

“…This, in turn, allows the film network to bind more intensely with water and thereby improves the hydrophilicity of the blend. 37 These findings are supported by the microscopic images of the films (Figure 1).…”

“…This can be attributed to an increase in void volume as a result of the destruction of the compact film network brought about by the aggregation of the constituents of the extract. 37 This can consequently influence the channel of water vapor through the films. 36 The WS of the films increased from 33.19 ± 1.48% for PP to 37.59 ± 1.88, 40.25 ± 1.33, and 46.49 ± 2.39% for PE1, PE5, and PE10, respectively.…”

Effect of chitosan/starch aldehyde‐catechin conjugate composite coating on the quality and shelf life of fresh pork loins

“…Antimicrobial activity of coating solutions against Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 19115, Escherichia coli ATCC 43895 and Salmonella typhimurium ATCC 14028 was tested according to Liu et al 29 . with some modifications.…”

“…Antimicrobial activity of coating solutions against Staphylococcus aureus ATCC 6538, Listeria monocytogenes ATCC 19115, Escherichia coli ATCC 43895 and Salmonella typhimurium ATCC 14028 was tested according to Liu et al 29 with some modifications. Briefly, 1 mL sample solution was mixed with 9 mL bacterial saline suspension [10 6 colony-forming unit (CFU) mL −1 ] and then incubated at 37 °C for 24 h. The bacterial culture was ten-fold serially diluted by sterile saline and 100 μL diluent was evenly distributed on plate count agar.…”

Development of linear low‐density polyethylene nanocomposite films for storage of sugarcane juice

“…It is widely accepted that packaging plays a crucial role in food preservation (Liu et al, 2021; Jafarzadeh et al, 2017). LLDPE is one of the preferred polymer‐based packaging materials used in food due to its improved chemical strength, puncture resistance, tear strength, and higher strength at a given density.…”