The effect of carrageenan-gluten ratio and garlic essential oil concentration on physical, mechanical, and antimicrobial properties of edible film

Abstract

Edible film can be made from natural polymers, such as fats, proteins, and polysaccharides. The combination of polysaccharides and proteins has the potential to form a film, it can improve the mechanical properties and physical properties of the film based on the complex structure formed. Furthermore, to improve the barrier properties by obstructing water vapour transmission and preventing the proliferation of spoilage microorganisms in food, it is important to present both hydrophobic substances and active compounds extracted from essential oils. This research aimed to find out the best formulation of gluten and garlic essential oil on the physical, mechanical, and bacteria-inhibitory properties of edible film. The method used in this research is the edible film made by combining carrageenan and gluten in several concentrations (7,5%; 10%; and 12,5%) and the addition of garlic essential oil at different concentrations (0%, 2%, and 4%), then observations were made on several test parameters such as solubility in water, thickness, water vapor transmission rate, tensile strength, and antibacterial properties of the film. Results obtained in the research demonstrated that the finest edible film treatment was found in addition of 12.5% gluten and addition of 4% garlic essential oil with the results of solubility parameter of 40.57% thickness of 0.73 mm tensile strength of 0.0009 N/mm2 and WVTR of 21.856 g/h/m2 and antibacterial properties against E. coli bacteria of 26.93 mm and against S. aurerus bacteria of 33.76 mm. This research concluded the addition of gluten and garlic oil could improve physical, mechanical, and antimicrobial properties edible film.