Pusat Pengajian Teknologi Industri - Tesis
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- PublicationEvaluation On The Effect Of Sago/Iota-Carrageenan Microgels Thickeners On Rheology, Texture And Sensory Of Pureed Carrot As Dysphagia Diet(2024-06)Rozman, Norrazatin HaidaThe inability or difficulty to swallow food and liquids is known as dysphagia. Providing soft, palatable and healthy texture modified foods for these group of people, is a major challenge for the food industry. Due to strong starchy flavour imparted from commercial starch-based dysphagia thickener, a study to develop microgels from other food biopolymers are needed. The objective of this study was to develop sago starch and iota-carrageenan based microgels with a functionality as food thickeners in pureed food. In phase 1, different concentrations of iota-carrageenan were added into sago starch dispersion. Microgels were fabricated using ultrasound treatment followed by spray drying process. A commercial dysphagia thickener that normally used at medical institutions and nursing homes was also included as a reference. Microgels exhibiting varying concentrations of iota-carrageenan demonstrated distinct behaviours in rheological and textural assessments. According to rheological tests, sago/iota-carrageenan microgels showed a predominant elastic tendency, with gʹ>gʺ in the frequency range. According to texture profile analysis (tpa), the sample containing 2.0 g of sago starch and 2.0 g of iota-carrageenan, ms50, exhibited excellent adhesiveness and elastic behaviour compared to a commercial thickener. The usage of sago/iota-carrageenan microgels in texture-modified food as texture modifier was further investigated in phase 2. Different sago/iota-carrageenan microgel concentrations and a commercial thickener were added to pureed carrots, and the textural properties were examined. Thixer, a commercial thickener made of modified corn starch, was used as a reference sample, while pureed carrot without the addition of thickener acts as a control xvi group.
- PublicationCharacterization Of Hemicellulose-Carboxymethyl Cellulose Blend Biofilm Fabricated From Oil Palm Trunk(2024-06)Ridzuan, Farah Fazlina MohdThe use of synthetic polymers is not essential due to environmental issues. Hence, the green materials have been extracted from biomass waste to produce a biopolymer in order to replace the synthetic polymer. Oil palm trunk (opt) is a solid waste that is abundantly available throughout the year. Due to this concern, hemicellulose film (hc) and carboxymethyl cellulose (cmc) were successfully prepared from oil palm trunk (opt) in this research study. Hc and cmc were blended by the solution casting method to produce blend biofilm at 0%, 20%, 40%, 60%, and 80 % hc and cmc loading. The cmc used was compared between commercial cmc (cmc-c) and the extracted opt cmc (cmc-t). The raw material and biofilm sample were characterized by chemical composition, fourier transmission infrared spectroscopy (ftir), energy-dispersive x-ray spectroscopy (sem-edx), x-ray diffraction (xrd), thickness, visual transparency, contact angle, solubility, moisture content, tensile strength, scanning electron microscopy (sem), differential scanning calorimetry (dsc), thermogravimetric analysis (tga) and biodegradability analysis. According to the results, chemical composition showed that the vascular bundle had more cellulose while the parenchyma had more hc. Moreover, the ftir of parenchyma and vascular bundle were successfully identified. Then, the sem-edx and xrd revealed the element in cmc, and the crystallinity of cellulose reduced when the chemical structure was interrupted by the addition of carboxymethyl group. Then, the result of hc-cmc blend biofilm revealed that the thickness increased while the visual transparency contact angle decreased.
- PublicationDevelopment Of Texture Modified Pumpkin Porridge For Dysphagia Diet: The Effects Of Fish Gelatin-Microbial Transglutaminase Gel Microparticles On The Rheological And Sensory Characteristics(2024-06)Rosly, Siti MunirahDysphagia is a condition affecting people of all ages, particularly the elderly and those with diseases like cancer, stroke, and dementia. It can reduce food intake and lead to nutritional deficiencies. To manage dysphagia, texture-modified food is prepared using thickeners like starch and gum, but these can leave a strong aftertaste or cause stomach discomfort. Therefore, in phase 1 of this study, gel microparticles were developed from fish gelatin and microbial transglutaminase enzyme (tga) as a potential thickener for texture-modified foods. The gel microparticles, ranging from 18μm to 1445μm, showed safe swallowing bolus properties with low adhesiveness and high cohesiveness, demonstrating the potential of gel microparticles with 0.7% mtga as a suitable thickener for texture modification. The rheological analysis showed that the sample with 0.7% mtga has weak gel properties with more elastic behaviour than viscous behaviour. In addition, sugar concentration increases hardness and cohesiveness while decreasing adhesiveness, making it as easy-to-swallow foods. In phase 2, the effects of gel microparticles on pumpkin porridge’s texture, rheological properties, and amylase enzyme response were analysed. The use of 2% fish gelatin-microbial transglutaminase (fgmt) gel microparticles showed similar texture, viscosity, and flow behaviour to the samples added with commercial thickeners. The elasticity of the porridge was dominant, with a higher resistance to the amylase reaction, indicating safe swallowing properties.
- PublicationModified Kenaf Bast Fibre Mat Reinforced Biopolymer Composite Enhanced With Spent Coffee Ground Microfiller(2024-09)Bairwan, Rahul DevThe escalating concern over the harmful effects of discarded plastics on the environment has prompted the development of eco-friendly 'green' polymers. Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a type of environmentally friendly polymer known for its biodegradability and renewability. However, its mechanical performance is somewhat restricted. Enhancing it can be achieved by combining it with natural fibers to produce green composites. These composites not only provide improved mechanical properties but also maintain biodegradability. In this study, an eco-friendly biocomposite is developed using PHBV and chemically modified non-woven kenaf bast fibers with Propionic anhydride (to improve the fiber/matrix interface and moisture resistance). The initial investigation was conducted on the optimum modified bast fiber loading reinforced PHBV composite. Composites were prepared through the compression molding of a matrix powder, with modified bast fiber mats interleaved within. The incorporation of 30% bast fiber mats into PHBV resulted in significant overall enhancement of properties. Subsequently, this study also explores the utilization of Spent Coffee Grounds (SCG), a residual product of the coffee industry as microfiller particles. These particles as microfillers are introduced into PHBV at varying particle sizes and concentrations (1%, 3%, 5%, and 7%) to create different PHBV-incorporated SCG particle variations. These variations were prepared using hot compression molding machine.
- PublicationEnhancement Of Cellulase-Poor Xylanase Production By Native Fungi Via Solid State Fermentation Process(2016-09)Tai, Wan YiHigh cost of cellulases remains the most significant barrier to the economical production of bio-ethanol from lignocellulosic biomass (LB). The present study aims at developing a local cellulolytic fungal strain with enhanced cellulolytic ability through random mutagenesis coupled with the feasibility of solid-state fermentation (SSF) by utilizing oil palm frond (OPF) as the substrate. Out of 95 wild isolates isolated from agricultural sites and tested both qualitatively and quantitatively, a native filamentous fungal strain designated DWA8 was found to be the top enzymatic secretor. During qualitative screening, 38 isolates were found to produce distinctive halo but only 23 were chosen to proceed with quantitative screening. For quantitative enzyme analysis, enzyme supernatant was extracted from the SSF process which was conducted using IxlO6 spore/mL inoculated onto 5 g of ground OPF, incubated at room temperature for 7 days. DWA8 was found to be the best candidate for further studies, as it produced the highest amount of fpase and xylanase with a considerably high amount of cmcase, which Aspergillus niger (Genebank accession no. KP299287) based on colony morphology and the best cultivation period where the cmcase, fpase and xylanase activities of A. niger DWA8 were 1.13 U/g, 2.55 U/g and 2.38 U/g respectively.