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Oil resistant thermoplastic elastomers (TPE) were prepared using mung bean thermoplastic starch (MTPS) blending with rubbers and sericin. Sericin was incorporated into MTPS as a compatibilizer. MTPS with sericin (MTPSS) was blended with natural rubber (NR) and epoxidized NR (ENR). Sericin at 5% improved the tensile strength (10 MPa), elastic recovery (52%) and morphology of the MTPSS/ENR blend. The mechanical properties, elastic recovery and morphology of the MTPSS5/NR blend were improved by the addition of ENR. The MTPSS/ENR showed palm (28%) and motor oils (8%) swelling resistance because of the hydrophilicity of MTPS and high polarity of ENR. The MTPSS/ENR/NR showed gasoline swelling resistance (104%) because of the hydrophilicity of MTPS and low polarity of NR. FTIR confirmed a reaction between the –NH groups of sericin and the epoxy groups of ENR. This reaction improved the compatibility, mechanical properties, elastic recovery, morphology and oils swelling resistance of the blends.

An antimicrobial thermoplastic starch (TPS) was developed by melt-mixing TPS with chlorhexidine gluconate (CHG) and epoxy resin (Er). The tensile strength and hardness of the TPSCh blend increased with the addition of Er (TPSCh/Er), especially at 5 wt% Er (TPSCh/Er5) (19.5 MPa and 95 %, respectively). The water contact angle of TPSCh/Er was higher than those of TPS and TPSCh because of the improved interfacial tension. Fourier transform infrared and nuclear magnetic resonance analyses confirmed the reaction between the epoxy groups of Er, hydroxyl groups of starch, and amino groups of CHG. TPSCh/Er5 exhibited a significantly lower CHG release than TPSCh owing to the rearrangement of TPSCh chains via Er crosslinking. TPSCh/Er0.5 and TPSCh/Er1 showed inhibition zones against both tested bacteria (Staphylococcus aureus and Bacillus cereus), whereas TPSCh/Er2.5, TPSCh/Er5, and TPSCh/Er10 showed inhibition zones only against S. aureus. Moreover, TPSCh and TPSCh/Er0.5-2.5 exhibited inhibition zones with Saccharomyces cerevisiae.

An egg coating was developed to preserve the internal quality of eggs by mixing cassava starch (CS), gelling agents and fatty acids. Hydroxypropyl methylcellulose (HPMC) and carboxymethyl cellulose (CMC) were used as gelling agents. Palm oil fatty acid (PO) was incorporated. Coated and non‐coated eggs were evaluated over a period of 4 weeks at 28 °C by the yolk colour, weight loss, albumen pH and Haugh unit testing. The quality of non‐coated eggs deteriorated from AA to B grade after 3 weeks, with values below the detection limit at 4 weeks. The optimum coating was 6/1/3 w/v% (CS/CMC/PO3). Contact angle, solubility and swelling in the water of the coating materials indicated the improvement of water resistance by addition of CMC and PO. Weight loss of the coated eggs was 4.9% lower than that of the non‐coated eggs (6.5%) after 4 weeks. The CS/CMC/PO3 emulsion coating significantly extended egg shelf life due to the high compatibility and water resistance of CMC as well as the hydrophobic property of PO.

An egg-coating material was developed to extend the shelf-life and freshness of eggs by blending cassava starch (CS) with gelling agents and waxes. The effects of the properties of this egg coating on egg quality were investigated. Hydroxypropyl methylcellulose (HPMC), carboxymethyl cellulose (CMC), beeswax, and paraffin wax were used. CS blended with low-molecular-weight paraffin (Paraffin(L)) and CMC coating material displayed a tensile strength of 4 MPa, 34% elongation at break, 0.0039 g day−1 m−2 water vapor permeability, and a water contact angle of 89° at 3 min. Eggs coated with CS/CMC/Paraffin(L) solutions had a Haugh unit value of 72 (AA grade) and exhibited a weight loss of 2.4% in 4 weeks. CMC improved the compatibility of CS and Paraffin(L). This improvement and the hydrophobicity of Paraffin(L) provided suitable mechanical and water-resistance properties to the coating material that helped to maintain the quality of the coated AA-grade eggs with low weight loss for 4 weeks.

An egg coating material was developed by blending cassava starch (CS) with gelling agents and wax. Hydroxyl propyl methyl cellulose and carboxymethyl cellulose (CMC) were added. Two waxes, beeswax and paraffin wax, were selected. CS blended with low-molecular-weight paraffin (Paraffin(L)) and CMC coating material displayed a tensile strength of 4 MPa, 34% elongation at break, 0.0039 g day−1 m−2 water vapor permeability, and a water contact angle of 89° at 3 min. Eggs coated with CS/CMC/Paraffin(L) solutions had a Haugh unit value of 72 (AA grade) and exhibited a weight loss of 2.4% in 4 weeks. CMC improved the compatibility of CS and Paraffin(L). This improvement and the hydrophobicity of Paraffin(L) conferred suitable mechanical and water-resistance properties on the coating material to maintain the quality of the coated eggs at AA grade with low weight loss for 4 weeks.

Thermoplastic elastomer (TPE) was developed by blending thermoplastic starch (TPS) with rubber. Thermoplastic starch-chitosan (TPSC) was prepared by the solution mixing of cassava starch, chitosan (CTS) and glycerol in acidified water (lactic acid 1 wt%) at 80 °C follow by melt mixing at 130 °C. Sodium benzoate (BEN) and chlorhexidine gluconate (Cl) were added during the solution mixing as additives for antimicrobial properties. TPSC was melt-mixed with epoxidized natural rubber (ENR) (70/30 wt/wt). The tensile strength and elongation at break of the TPSC/ENR increased with the additive content. Elastic recovery was improved by the addition of Cl. A new peak in the FTIR data confirmed the reaction between the reactive functional groups of the CTS and the additives with the epoxy groups of ENR. These reactions and miscibility of the TPSC/ENR/additives blends improved the mechanical properties, elasticity, morphology, and antimicrobial properties of the blends.

A blend of cassava starch (CS), carboxymethyl cellulose (CMC), and paraffin was prepared as a coating material to maintain the quality of eggs during 4 wk of storage at different temperatures. The efficacy of the CS/CMC/paraffin (6/1/0.5% w/v) coating was investigated in terms of the Haugh unit (HU), weight loss, pH, and microbial load at the end of storage. The best egg storage temperature was 4°C, which maintained an HU of grade AA in coated and uncoated eggs for 4 wk. Lower weight loss (2.14%) was observed in coated eggs at 4°C storage than at 30°C storage (3.26%). The pH in the albumen of coated and uncoated eggs at 4°C increased from 6.84 to 6.88 and 7.01 to 7.03, respectively, after 4 wk of storage. No microbes were detected in the coated and uncoated eggs at 4°C. The maximum microbial count was 728 ± 35 cfu/mL in uncoated eggs at 30°C storage. Egg coating prevented microbial contamination of eggs stored at 30°C for 4 wk. The freshness of the eggs did not affect the nutrient content. The egg-coating material effectively maintained egg quality, prevented microbial contamination of eggs, and increased the shelf life of eggs at storage temperatures of 25 and 30°C.