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Active food packaging is currently of high demand in food industries to provide protections to food. Food packaging is not only used to store and protect food from the environment, but also to provide functional values with the incorporation of active agent. Essential oils (EOs) extracted from a variety of plants represent active ingredients of natural origin which provide numerous benefits to food, aromatherapy, pharmaceutical, and food packaging industries due to their functional properties. Numerous researches have been carried out in developing active food packaging such as insect repellent packaging containing essential oils. Insect repellent packaging could create safety measures by repelling insect from exterior environment or the inhibition of larvae from food within. In this paper, different application of EOs on different types of food packaging, applications, processing methods, migration of active compounds and performance of insect repellency are reviewed. Future perspectives and applications of insect repellence using safe, natural and more effective strategies are also discussed. EOs as the active insect repellent agents in food packaging offer great opportunities to protect the quality of food. Some important factors such as legislative concerns (e.g. toxicity test, migration of active substances from packaging materials), economics, and further study on the release period of active agent to the environment should be considered to successfully implement insect repellent agents in food packaging.

Malaysia is in a transition state towards a more developed country which stresses on sustainable development. The Malaysia government has introduced several policies related to the installation of renewable energy to secure its energy demand, which has an annual growth rate of 8.1%. In the Iskandar region in Johor, low-carbon development projects have been continuously implemented under the low-carbon society blueprint for Iskandar Malaysia. The selected village, Layang-Layang, is located within a palm oil plantation and is part of Malaysia rural transformation centre (RTC) project where a community-composting pilot plant was successfully set up in 2016. This study analysed the environmental and economic performance of the community-composting project. A total of four scenarios is analysed regarding their environmental performance (greenhouse gas emission) and the economic returns of investment. Scenario A served as the baseline study where all the municipal waste is sent to a landfill site. Scenario B involved the current pilot-scale composting plant practised by 100 residents in Layang-Layang. Scenario C considered the scaled-up composting scenario (3000 residents) based on the data from scenario A and B in Layang-Layang. Scenario D considered the treatment of the municipal wastes (3000 residents) to generate biogas via anaerobic digestion (AD) where the digestate was used for composting. In this study, co-composting of food waste from a residential area with the green waste from the plantation showed a reduction potential of 96.79% (Scenario C) on greenhouse gas (GHG) emission as compared to the landfill (Scenario A) and a reduction of 99.67% on GHG emission for the integrated AD and composting system (Scenario D). The scaled-up composting in scenario C was more attractive for investment as compared to scenario D. Scenario C showed a shorter minimal year for the return of investment (3.09 years) as compared to Scenario D (6.17 years) with electricity generation from biogas.

The current study was employed to investigate the effect of solvent type, extraction time and bran ratio on the rice bran oil (RBO) properties from three varieties of rice bran namely Bario, lowland and upland rice. RBO was extracted by using soxtherm extraction method using methanol solvent at different extraction time (3, 4 and 5 h) and bran ratio (10, 20 and 30 g). Free fatty acid (FFA), total phenolic content (TPC) and antioxidant properties were assessed. Solvent that has low polarity exhibited the attraction of polar component of oil with the highest yield by ethanol (16.16%), followed by methanol (15.38%). FFA contents occurred higher in lowland types of rice bran in all types of solvents at $$P

The encapsulation of vitamin E using combined solution of maltodextrin and sodium caseinate by spray-drying technique was investigated. Spray drying is the most commonly used method in the food industry. The physical characterizations of the encapsulated vitamin E gave valuable information on the surface morphology, size, shape, solubility, and moisture content. The micrograph of the vitamin E microcapsules indicated that the feed composition affects the morphology of the product. The particle sizes measured were ranging from 13 to $$29~\upmu \hbox {m}$$ with moderate moisture contents (4.5–4.98%) and were not affected by the amount of oil and type of wall material used. The solubility test indicated that there is a relationship between the amount of maltodextrin in formulations and the solubility. The microcapsule was considered soluble since the solubility time was obtained from 178 to 251 s.

To find out the best structure of acrylamide-based hydrogels, three different composites are synthesized and characterized. Polyacrylamide-based hydrogels were obtained by chemical crosslinking of MBA using acrylamide, sodium carboxymethylecellulose (NaCMC), N,N,N′,N′-tetramethylethylenediamine (TEMED) and ammonium persulfate (APS) as the initiators. The interest in MgO nanoparticles is not only due to their stability under harsh process conditions but also for human health, where they are known to be necessary minerals. It is expected that the structure of the hydrogels can be affected positively by using MgO as a nanoparticle in their composite. To control the initial burst release through modification of the structure of the matrix, the MgO nanoparticles are applied. These nanoparticles can affect the release mechanism. In the current research, FESEM, NMR, DTA/TGA and DSC are studied for the structure of polymers. In the FESEM, existing MgO inside the hydrogel system brings about a shift in the porosity of hydrogels. The 1H NMR spectrum of polymers showed characteristic proton peaks at 4.6 and 4.7, 6.1 and 6.2 ppm. An endothermic peak indicating loss of weakly bound water molecules from the hydrogel network is shown in DTA curves of hydrogels at around 80 °C. An exothermic peak at around 270 °C for Aam and Aam/NaCMC hydrogels and also a peak at 360 °C in Aam and Aam/NaCMC hydrogels and 320 °C for Aam/NaCMC/MgO is shown. The DSC profiles of the hydrogels show that water has a higher evaporation temperature in the polyacrylamide hydrogel (84 °C).The largest depression of the temperature was observed on the Aam/NaCMC/MgO hydrogel (∆T = 94 °C), which confirmed the higher hydrophilicity of Aam/NaCMC/MgO as compared to pure Aam hydrogel and Aam/NaCMC hydrogel.

The α-tocopherol (α-toc) degrades faster than both γ- and δ-toc; its degradation rate is 10 times faster than δ-toc. The foremost factors that could affect the stability of vitamins upon storage are light, oxygen, and heat. Thus, this study aimed to investigate the thermal, storage, and physical stability of the α-tocopherol/β-cyclodextrin (α-toc/β-CD) powder obtained via microwave heating and encapsulation process. DSC, TG, and DTG were performed for thermal stability characterizations, while storage study was performed to investigate the stability of the encapsulated and non-encapsulated α-toc stored at 5, 28, and 50 °C for 42 days. The results obtained were then fitted with first-order degradation kinetic model to obtain the half-life for each sample. The physical stability in terms of flowability and compressibility was also studied during the storage. Encapsulation of α-toc into β-CD has successfully increased the thermal stability of α-toc to a higher decomposition temperature from 280 to 300 °C. The storage study showed that the encapsulation of α-toc by β-CD using the microwave technique has successfully improved the shelf life of α-toc with the half-life of 990, 523 and 126 days for samples stored at 5, 28, and 50 °C, respectively, with a good flow powder characteristics except for powder stored at 50 °C which showed passable flow powder characteristics after 42 days of storage.

In addition to offering a host of health benefits, antimicrobial (AM) wheat-based packaging is a promising form of active food packaging with great economic and environmental potential. The main objective of this study is to develop a formulation of AM wheat-based film in which the active compound, lysozyme, is incorporated into the polymeric material. A solution casting method was used in the film preparation, and lysozyme was incorporated prior to casting. The resultant film is slightly less opaque, more translucent and whitish in appearance, implying that the AM film could retain similar property with the initial opacity value of the wheat-based film. The water uptake of wheat-film is reduced with the incorporation of lysozyme. The reduction in moisture content of AM film indicates a relationship between lysozyme and water molecules in the diffusion mechanism throughout the film matrices. This film helps to reduce the growth of E. coli and B. subtilis to 1.74 and 3.48 log CFU/mL, respectively, for an incubation of 48 h. FTIR analysis implies the consistency of the chemical composition and structure of the AM film compared to the control film, which indicates that the addition of lysozyme into the wheat-based film did not affect or alter the carbonyl function groups of the wheat-based film. The study will help the researcher to discover and understand wheat-based films for incorporating antimicrobial properties and to explore new matrices for further development.

The purpose of this study was to investigate the preparation of formulated water– in–soybean oil–in–water emulsions by repeated premix membrane emulsification method using a cellulose acetate membrane. The effect of selective membrane emulsification process parameters (concentration of the emulsifiers, number of passes of the emulsions through the membrane and storage temperature) on the properties and stability of the developed emulsions were also investigated. 1, 3, 6, 8-pyrenetetrasulfonic acid tetrasodium salt (PTSA) was used as a hydrophilic model ingredient for the encapsulation of bioactive substances. W/O emulsions with 7 wt% (weight percentage) PGPR displays homogeneous and very fine dispersions, with the median diameter at 0.640 μm. Meanwhile, emulsions prepared by membrane emulsification (fine W/O/W) showed the highest stability at Tween 80 concentrations of 0.5 wt.% (weight percentage). It concluded that at 7 wt.% (weight percentage) PGPR concentration and 0.5 wt.% (weight percentage) Tween 80 concentrations, the most uniform particles with minimum mean size of oil drops (9.926 μm) were obtained after four passes through the membrane. Thus, cellulose acetate membrane can be used for preparing a stable W/O/W emulsions by repeated premix ME due to low cost and relatively easy to handle.

In this study, MgO nanoparticles are applied to control the initial burst release by modification of matrix structure, thereby affecting the release mechanism. The effects of MgO nanofiller loading on the in vitro release of a model drug are investigated. Surface topography and release kinetics of hydrogel nanocomposites are also studied in order to have better insight into the release mechanism. It was found that the incorporation of MgO nanofillers can significantly decrease the initial burst release. The effect of genipin (GN) on burst release was also compared with MgO nanoparticles, and it was found that the impact of MgO on burst release reduction is more obvious than GN; however, GN cross-linking caused greater final release compared to blanks and nanocomposites. To confirm the capability of nanocomposite hydrogels to reduce burst release, the release of β-carotene in Simulated Gastric Fluid and Simulated Intestinal Fluid was also carried out. Thus, the application of MgO nanoparticles seems to be a promising strategy to control burst release.

Genipin cross-linked kappa-carrageenan/hydroxyethyl cellulose hydrogels were prepared and the effect of cross-linking on hydrogels characteristics was investigated. Swelling and transform mechanisms of both native and cross-linked gels in different pH were also studied. We found that the concentration of genipin affects the physical stability of gels. The optimum concentration that a cross-linked hydrogel molecular structure can be in its most stable form is also discussed. Native hydrogels exhibited more swelling in alkaline medium than acidic and neutral; however, by increasing the cross-linker concentration, the swelling ability in neutral medium increased so that genipin cross-linked hydrogels could swell in pH 7 more than in pH 1.2 and 12. Fourier transform infrared spectroscopy (FTIR) was applied to study the formation of new bonding due to genipin reactions and explain hydrogels’ stability in various concentrations. Differential scanning calorimetry (DSC) measurements reveal that by increasing genipin, the gel ability to hold water increases to some point and then decreases due to less structural stability. X-ray diffraction (XRD) and field emission scanning electron microscope (FESEM) tests were performed to study the crystallinity changes and microstructure of hydrogels. Finally, the power law model was applied to study the transform mechanism of hydrogels.