Mechanical and Physical Properties of Pea Starch Edible Films in the Presence of Glycerol

Abstract

The mechanical properties and moisture sorption at relative humidity (RH) range of 11–94%, water vapor permeability (WVP), solubility in water and color of the pea starch films as a function of glycerol were examined. The results showed that increasing the concentration of plasticizer resulted in improvement of the tensile strength of the films at RH <43%, the percent elongation as well as the deformation at break at RH <84%. Increasing plasticizer content and RH also resulted in films with lower Young's modulus, lower puncture force, but higher puncture deformation. Furthermore, increasing plasticizer content led to the films with more opaque appearance. Films prepared with 15 and 25% glycerol had lower WVP in comparison with unplasticized film. This study provides information regarding the advantageous or disadvantageous of possible application of pea starch films in food packaging industry. Practical Application Starch edible films have been utilized for packaging technologies and edible coatings. Pea starch has been found to produce the films with improved physical and mechanical properties in comparison with films prepared from other starches due to high amount of amylose. The development of pea starch film with improved functions affects its application. Pea starch edible films may find practical applications in the poultry, meat, seafood, fruit, vegetable, grains and candies industries.

Development of edible blend films with good mechanical and barrier properties from pea starch and guar gum

“…This behavior could be owing to their hydrophilicity nature and accessible hydroxyl groups which are capable to interact with water by hydrogen bonds. Thus, water molecules are more freely absorbed into the surface of the films (i.e., higher solubility) and permeate through the film structure more simply (i.e., higher diffusivity) bringing about the increase in WVP . The addition of glycerol can make the film less compact by increasing the molecular mobility and enhancing free volume in the film network and can increase the sorption of water.…”

“…After the permeation tests, the film thickness was measured and WVP (g Pa −1 s −1 m −1 ) was calculated as: where Δ m /Δ t is the weight of moisture gain per unit of time (g/s), X is the average film thickness (mm), A is the area of the exposed film surface (m 2 ), and Δ P is the water vapor pressure difference between the two sides of the film (Pa). WVP was measured for three replicated samples for each type of film .…”

“…Eight film specimens (40 × 15 mm 2 ) of each formulation were used for mechanical tests and fixed between the grips of the machine. The maximum load ( N ) and extension (mm) curves were recorded to calculate tensile strength (TS), percent elongation at break (%E), and Young's modulus (YM) at break of the films using a tensile test at crosshead speed of 1 mm/s and initial grip distance 40 mm .…”

“…Force ( N ) and deformation (mm) values at the puncture point were then recorded to represent the puncture force (PF) ( N ) and deformation (PD) (mm) of the films. For each sample, eight replicates were performed .…”

Effect of Biocomposite Edible Coatings Based on Pea Starch and Guar Gum on Nutritional Quality of “Valencia” Orange During Storage

“…In our previous studies, it has been demonstrated that pea starch in combination with guar gum produced biocomposite edible films with desirable physical, optical, and mechanical characteristics . It was shown that pea starch and guar gum (PSGG) can be potential alternatives for production of renewable source‐based biodegradable edible coatings owing to their long polymeric chain, high molecular weight, and wide availability.…”