Nuclear chemistry

Modified atmosphere

Preservative

Antimicrobial

Coating

Chitosan

Biochemistry

Lipid oxidation

Food science

TBARS

Loin

Organic chemistry

Gallic acid

Oxygen

Vacuum packing

Lipid peroxidation

Thiobarbituric acid

Antioxidant

Chemistry

Nisin

Shelf life

Food Control

The objective of this research was to investigate a combination of nisin/gallic acid/chitosan coating and high-oxygen modified atmosphere packaging (HO MAP, 80% O2 + 20% CO2) on the preservation of fresh pork loin during cold storage (2 ± 1 °C, 20 days). Fresh pork loins were coated with 2% chitosan solution alone (CHI), 0.2% gallic acid in 2% chitosan (CHI/GA), 0.2% nisin in 2% chitosan (CHI/N), and 0.2% nisin, 0.2% gallic acid in 2% chitosan (CHI/N/GA) solutions. Pork samples were analysed for pH, colour (L*, a*, b*), free thiol group, thiobarbituric acid reactive substances (TBARS), Warner-Bratzler shear force (WBSF) and total viable count (TVC). Results showed that, compared with other coating solutions, CHI/N/GA coating had better colour protection, lower protein and lipid oxidation, and synergistic bactericidal effect, as evidenced by higher a* value (6.85) and lower hue angle (67.95), the highest free thiol group content (47.07 nmol thiol/mg protein), lowest TBARS value (0.28 mg MDA/kg) and lowest TVC (4.67 log cfu/g). This study suggests that combination of nisin/gallic acid/chitosan coating with HO MAP could be applied as a hurdle packaging technology to preserve fresh pork.

Effect of chitosan/nisin/gallic acid coating on preservation of pork loin in high oxygen modified atmosphere packaging