ABSTRACT
This study investigated a blend of poly (lactic acid) (PLA) and Saqqez gum, with a weight ratio of 70:30, respectively, along with two plasticizers, acetyl tributyl citrate (ATBC) and polyethylene glycol (PEG), at three different concentrations (14%, 16% and 18% by weight of the PLA). The blend was analyzed using differential scanning calorimetry (DSC), scanning electron microscopy (SEM), tensile tests, water-absorption behavior (coefficients of water absorption, sorption, diffusion and permeability of the samples during 240 h) and chemical resistance (exposure to 1 mol/L HCl and 1 mol/L NaOH for 240 h). The desired elastomer blend was then used to prepare natural chewing gum, which was subsequently subjected to texture profile analyzer (TPA) tests and sensory evaluation. The results showed that the addition of both plasticizers increased the tensile properties of the blend. Compared to neat PLA, all the blends exhibited an increase in elongation at break and a decrease in yield strength, with the maximum elongation at break (130.6%) and the minimum yield strength (12.2 MPa) observed in the blend containing 16% ATBC. Additionally, all the thermal attributes studied, including Tg, Tc and Tm, were lower than those of neat PLA, and the Tg values deviated from the values predicted via Fox's equation. SEM images of the blends confirmed that plasticization improved the homogeneity and distribution of the components in the blend structure. PEG 18% and ATBC 16% exhibit the highest and lowest water-absorption behavior, respectively. Regarding chemical resistance, all blends showed weight gain when exposed to HCl, while no weight loss was observed for resistance to NaOH. The chewing gum sample obtained similar values for the mentioned tests compared to the commercial control sample. Overall, the results indicate that plasticization enhances the structure and performance of the PLA/Saqqez gum blend and further investigation is warranted.
ABSTRACT
The gum base mass is a colloidal system and the main component of chewing gum; which is an inert, non-nutritious, indigestible, and insoluble part of chewing gum, therefore this substance does not dissolve in the mouth when chewed. The gum base plays the most crucial role in determining the mechanical properties, flexibility, and overall quality of chewing gum. Moreover, it acts as a delivery system to transport sweeteners, flavorings, and other ingredients in chewing gum. Despite the massive market for chewing gum and the provision of a list of the main ingredients in gum base by the Code of Federal Regulations and some international organizations, there is a lack of information about chewing gum base and its compositions in the literature. Therefore, the purpose of this review is to present an overview of the characteristics, ingredients and applications, production process, assessment, and modification methods of the gum base along with the advances and approaches in biodegradability. Biodegradability concerns play a promoting role in the research and development of chewing gum and its applications in the food industry, medical and dental sectors. Reviewing previous studies can surely help for faster development of this path.
