Displaying publications 221 - 240 of 317 in total

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  1. Razali MF, Mahmud AS, Mokhtar N
    J Mech Behav Biomed Mater, 2018 Jan;77:234-241.
    PMID: 28954242 DOI: 10.1016/j.jmbbm.2017.09.021
    NiTi arch wires are used widely in orthodontic treatment due to its superelastic and biocompatibility properties. In brackets configuration, the force released from the arch wire is influenced by the sliding resistances developed on the arch wire-bracket contact. This study investigated the evolution of the forces released by a rectangular NiTi arch wire towards possible intraoral temperature and deflection changes. A three dimensional finite element model was developed to measure the force-deflection behavior of superelastic arch wire. Finite element analysis was used to distinguish the martensite fraction and phase state of arch wire microstructure in relation to the magnitude of wire deflection. The predicted tensile and bending results from the numerical model showed a good agreement with the experimental results. As contact developed between the wire and bracket, binding influenced the force-deflection curve by changing the martensitic transformation plateau into a slope. The arch wire recovered from greater magnitude of deflection released lower force than one recovered from smaller deflection. In contrast, it was observed that the plateau slope increased from 0.66N/mm to 1.1N/mm when the temperature was increased from 26°C to 46°C.
    Matched MeSH terms: Tensile Strength
  2. Ahmad S, Singh VA, Hussein SI
    J Orthop Surg (Hong Kong), 2017 8 29;25(3):2309499017727946.
    PMID: 28844199 DOI: 10.1177/2309499017727946
    Meniscal allograft transplantation may be a better alternative for the treatment of irreparable meniscal injury compared to other forms of treatment. However, it remains to be seen whether the use fresh frozen allograft is better than cryopreserved allograft in treating this type of injury. We hypothesized that cryopreserved meniscal allograft would work better in maintaining the original biomechanical properties compared to fresh frozen ones, due to the lower amount of damage it incurs during the storage process. We examined young and healthy human menisci obtained from orthopedic oncology patients who underwent resection surgeries around the knee. The menisci obtained were preserved via cryopreservation and deep-freezing process. Traction tests were carried out on the menisci after 6 weeks of preservation. Twelve pairs ( N = 24) of menisci were divided equally into two groups, cryopreservation and deep frozen. There were six males and six female menisci donors for this study. The age range was between 15 and 35 years old (24.9 ± 8.6 years). Cryopreserved specimens had a higher ultimate tensile strength (UTS; 8.2 ± 1.3 Mpa vs. 13.3 ± 1.7 Mpa: p < 0.05) and elastic modulus (61.7 ± 27.6 Mpa vs. 87.0 ± 44.10 Mpa: p < 0.05) compared to the fresh frozen specimens. There was a significant difference in UTS ( p < 0.05) between the two groups but no significant difference in their elastic modulus ( p > 0.05). The elastic modulus of the preserved meniscus was similar to fresh normal menisci taken from other studies (60-120 Mpa; cryopreserved (87.0 ± 44.1) and fresh frozen (61.7 ± 27.5)). Cryopreserved menisci had a higher elastic modulus and point of rupture (UTS) compared to fresh frozen menisci. Cryopreservation proved to be a significantly better method of preservation, among the two methods of preservation in this study.
    Matched MeSH terms: Tensile Strength
  3. Hassan MI, Sultana N
    3 Biotech, 2017 Aug;7(4):249.
    PMID: 28714045 DOI: 10.1007/s13205-017-0889-0
    Considering the important factor of bioactive nanohydoxyapatite (nHA) to enhance osteoconductivity or bone-bonding capacity, nHA was incorporated into an electrospun polycaprolactone (PCL) membrane using electrospinning techniques. The viscosity of the PCL and nHA/PCL with different concentrations of nHA was measured and the morphology of the electrospun membranes was compared using a field emission scanning electron microscopy. The water contact angle of the nanofiber determined the wettability of the membranes of different concentrations. The surface roughness of the electrospun nanofibers fabricated from pure PCL and nHA/PCL was determined and compared using atomic force microscopy. Attenuated total reflectance Fourier transform infrared spectroscopy was used to study the chemical bonding of the composite electrospun nanofibers. Beadless nanofibers were achieved after the incorporation of nHA with a diameter of 200-700 nm. Results showed that the fiber diameter and the surface roughness of electrospun nanofibers were significantly increased after the incorporation of nHA. In contrast, the water contact angle (132° ± 3.5°) was reduced for PCL membrane after addition of 10% (w/w) nHA (112° ± 3.0°). Ultimate tensile strengths of PCL membrane and 10% (w/w) nHA/PCL membrane were 25.02 ± 2.3 and 18.5 ± 4.4 MPa. A model drug tetracycline hydrochloride was successfully loaded in the membrane and the membrane demonstrated good antibacterial effects against the growth of bacteria by showing inhibition zone for E. coli (2.53 ± 0.06 cm) and B. cereus (2.87 ± 0.06 cm).
    Matched MeSH terms: Tensile Strength
  4. Balaji AB, Ratnam CT, Khalid M, Walvekar R
    J Biomater Appl, 2018 03;32(8):1049-1062.
    PMID: 29298552 DOI: 10.1177/0885328217750476
    The effect of electron beam radiation on ethylene-propylene diene terpolymer/polypropylene blends is studied as an attempt to develop radiation sterilizable polypropylene/ethylene-propylene diene terpolymer blends suitable for medical devices. The polypropylene/ethylene-propylene diene terpolymer blends with mixing ratios of 80/20, 50/50, 20/80 were prepared in an internal mixer at 165°C and a rotor speed of 50 rpm/min followed by compression molding. The blends and the individual components were radiated using 3.0 MeV electron beam accelerator at doses ranging from 0 to 100 kGy in air and room temperature. All the samples were tested for tensile strength, elongation at break, hardness, impact strength, and morphological properties. After exposing to 25 and 100 kGy radiation doses, 50% PP blend was selected for in vivo studies. Results revealed that radiation-induced crosslinking is dominating in EPDM dominant blends, while radiation-induced degradation is prevailing in PP dominant blends. The 20% PP blend was found to be most compatible for 20-60 kGy radiation sterilization. The retention in impact strength with enhanced tensile strength of 20% PP blend at 20-60 kGy believed to be associated with increased compatibility between PP and EPDM along with the radiation-induced crosslinking. The scanning electron micrographs of the fracture surfaces of the PP/EPDM blends showed evidences consistent with the above contentation. The in vivo studies provide an instinct that the radiated blends are safe to be used for healthcare devices.
    Matched MeSH terms: Tensile Strength
  5. Nor, M.H.M., Nazmi, N.N.M., Sarbon, N.M.
    MyJurnal
    The aim of this study was to investigate the functional properties of chicken skin gelatin films with varied concentrations of a hydrophilic plasticizer. Gelatin film solutions with different glycerol concentrations A(control), B(5%), C(10%), D(15%) and E(20%), were stirred at 45°C for 20min and oven dried at 45°C. Film characterization determination were included, tensile strength (TS), elongation at break (EAB), water vapor permeability (WVP), solubility, transparency, moisture content, Fourier Transform Infrared Spectroscopy (FTIR), and X-ray Diffraction (X-RD). Glycerol added resulted in improvement of TS and WVP properties. Film B (5% glycerol) demonstrated low EAB (106%), WVP (0.0175 g.mm/h.m2.k.Pa) and solubility (58.64%), but with high TS (3.64 MPa), moisture content (16.0%), UV light transmission (0.04%) and transparency (0.81) compared to films C, D and E. FTIR spectrum analyses demonstrated an aliphatic alcohol group only for Film E (20% glycerol). Hence, chicken skin gelatin film at 5% glycerol concentration showed the most promising potential for industrial food processing applications.
    Matched MeSH terms: Tensile Strength
  6. Asrofi M, Abral H, Putra YK, Sapuan SM, Kim HJ
    Int J Biol Macromol, 2018 Mar;108:167-176.
    PMID: 29191420 DOI: 10.1016/j.ijbiomac.2017.11.165
    This paper characterizes properties of biocomposite sonicated during gelatinization. The biocomposite consisted of tapioca starch based plastic reinforced by 10% volume fraction of water hyacinth fiber (WHF). During gelatinization, the biocomposite was poured into a rectangular glass mold then vibrated in an ultrasonic bath using 40kHz, 250W for varying durations (0, 15, 30, and 60min). The resulting biocomposite was then dried in a drying oven at 50°C for 20h. The results of this study indicate that a biocomposite with optimal properties can be produced using tapioca starch and WHF if the gelatinizing mixture is exposed to ultrasound vibration for 30min. After this vibration duration, tensile strength (TS) and tensile modulus (TM) increased 83% and 108%. A further 60min vibration only increased the TS at 13% and TM at 23%. Moisture resistance of the biocomposite after vibration increased by around 25% reaching a maximal level after 30min. Thermal resistance of the vibrated biocomposites was also increased.
    Matched MeSH terms: Tensile Strength
  7. Rajendran Royan NR, Sulong AB, Yuhana NY, Chen RS, Ab Ghani MH, Ahmad S
    PLoS One, 2018;13(5):e0197345.
    PMID: 29847568 DOI: 10.1371/journal.pone.0197345
    The use of rice husks (RH) to reinforce polymers in biocomposites are increasing tremendously. However, the incompatibility between the hydrophilic RH fibers and the hydrophobic thermoplastic matrices leads to unsatisfactory biocomposites. Surface modification of the fiber surface was carried out to improve the adhesion between fiber and matrix. In this study, the effect of surface modification of RH via alkali, acid and ultraviolet-ozonolysis (UV/O3) treatments on the properties of composites recycled high density polyethylene (rHDPE) composites was investigated. The untreated and treated RH were characterized by Fourier Transform Infrared (FTIR) and Scanning Electron Microscope (SEM). The composites containing 30 wt% of RH (treated and untreated) were then prepared via extrusion and followed by compression molding. As compared to untreated RH, all surface treated RH exhibited rougher surface and showed improved adhesion with rHDPE matrix. Tensile strength of UV/O3-treated RH composites showed an optimum result at 18.37 MPa which improved about 5% in comparison to the composites filled with untreated RH. UV/O3 treatment promotes shorter processing time and lesser raw material waste during treatment process where this is beneficial for commercialization in the future developments of wood plastic composites (WPCs). Therefore, UV/O3 treatment can be served as an alternative new method to modify RH surface in order to improve the adhesion between hydrophilic RH fibre and hydrophobic rHDPE polymer matrix.
    Matched MeSH terms: Tensile Strength
  8. Fan HY, Duquette D, Dumont MJ, Simpson BK
    Int J Biol Macromol, 2018 Dec;120(Pt A):263-273.
    PMID: 30130612 DOI: 10.1016/j.ijbiomac.2018.08.084
    Composite films comprised of salmon (Salmo salar) skin gelatin and zein were prepared via crosslinking with glutaraldehyde. Response surface methodology (RSM) was used to optimize film composition to maximize tensile strength (TS) and elongation at break (EAB), and to minimize water solubility (WS) of the films. The significant (P strength as a function of increasing humidity.
    Matched MeSH terms: Tensile Strength
  9. Habiba U, Lee JJL, Joo TC, Ang BC, Afifi AM
    Int J Biol Macromol, 2019 Jun 15;131:821-827.
    PMID: 30904531 DOI: 10.1016/j.ijbiomac.2019.03.132
    In this study, chitosan/polyvinyl alcohol/TiO2 nanofiber was fabricated via electrospinning at a pump rate of 1.5 mL/h and voltage 6 kV. Field-emission scanning electron microscopic images showed bead free finer nanofiber. Fourier transform infrared spectra proved the formation of strong bond among chitosan, polyvinyl alcohol and TiO2. X-ray powder diffraction showed that TiO2 became amorphous in the composite nanofiber. Toughness and thermal stability of the chitosan/PVA nanofibrous membrane was increased with addition TiO2. The chitosan/PVA/TiO2 nanofibrous membrane was stable at basic medium. But degraded in acidic and water medium after 93 and 162 h, respectively. The adsorption mechanism of congo red obeyed the Langmuir isotherm model. On the other hand, adsorption characteristic of methyl orange fitted well with both Langmuir and Freundlich isotherm models. The maximum adsorption capacity of the resulting membrane for congo red and methyl orange is 131 and 314 mg/g, respectively. However, a high dose of adsorbent was required for congo red.
    Matched MeSH terms: Tensile Strength
  10. Abdullah AM, Mohamad D, Rahim TNAT, Akil HM, Rajion ZA
    Mater Sci Eng C Mater Biol Appl, 2019 Jun;99:719-725.
    PMID: 30889745 DOI: 10.1016/j.msec.2019.02.007
    This study reports the influence of ZrO2/β-TCP hybridization on the thermal, mechanical, and physical properties of polyamide 12 composites to be suited for bone replacement. Amount of 15 wt% of nano-ZrO2 along with 5,10,15,20 and 25 wt% of micro-β-TCP was compounded with polyamide 12 via a twin-screw extruder. The hybrid ZrO2/β-TCP filled polyamide 12 exhibited higher thermal, mechanical and physical properties in comparison to unfilled polyamide 12 at certain filler loading; which is attributed to the homogenous dispersion of ZrO2/β-TCP fillers particle in polyamide 12 matrix. The hybrid ZrO2/β-TCP filled PA 12 demonstrated an increment of tensile strength by up to 1%, tensile modulus of 38%, flexural strength of 15%, flexural modulus of 45%, and surface roughness value of 93%, as compared to unfilled PA 12. With enhanced thermal, mechanical and physical properties, the newly developed hybrid ZrO2/β-TCP filled PA 12 could be potentially utilized for bone replacement.
    Matched MeSH terms: Tensile Strength
  11. Razali MH, Ismail NA, Mat Amin KA
    Int J Biol Macromol, 2020 Jun 15;153:1117-1135.
    PMID: 31751725 DOI: 10.1016/j.ijbiomac.2019.10.242
    The synthesized titanium dioxide nanotubes (TiO2-NTs) were emerged as wound healing enhancer as well as exhibited significant wound healing activity on Sprague Dawley rats. In our present study, the blends of GG and TiO2-NTs bio-nanocomposite film was characterised by fourier transform infrared (FTIR), x-ray diffraction (XRD), scanning electron microscopy (SEM), thermogravimetric analysis, atomic force microscopy (AFM). The morphology of TiO2-NTs was investigated using transmission electron microscopy (TEM). The mechanical properties study shows that the GG + TiO2-NTs (20 w/w %) bio-nanocomposite film possessed the highest tensile strength and young modulus which are (4.56 ± 0.15) MPa and (68 ± 1.63) MPa, respectively. GG + TiO2-NTs (20 w/w %) also displays the highest antibacterial activity with (16 ± 0.06) mm, (16 ± 0.06) mm, (14 ± 0.06) mm, and (12 ± 0.25) mm inhibition zone were recorded against Staphylococcus aureus, Streptococcus, Escherichia coli, and Pseudomonas aeruginosa. The prepared bio-nanocomposite films have good biocompatibility against 3T3 mouse fibroblast cells and caused accelerated healing of open excision type wounds on Sprague Dawley rat model. The synergistic effects of bio-nanocomposite film like good swelling and WVTR properties, excellent hydrophilic nature, biocompatibility, wound appearance and wound closure rate through in vivo test makes it a suitable candidate for wound healing applications.
    Matched MeSH terms: Tensile Strength
  12. Mohammed BS, Haruna S, Wahab MMA, Liew MS, Haruna A
    Heliyon, 2019 Sep;5(9):e02255.
    PMID: 31687531 DOI: 10.1016/j.heliyon.2019.e02255
    In this present experimental study, geopolymer cement is developed using high calcium fly ash and used in the production of one-part alkali-activated binders. At 8-16 percent of the total precursor materials, the HCFA was activated with anhydrous sodium metasilicate powder and cured in ambient condition. Five mixtures of one-part geopolymer paste were intended at a steady w/b proportion. Density, flowability, setting time, compressive strength, splitting tensile strength and molar ratio impact were envisaged. It was observed that the setting time of the designed one-part geopolymer paste decreases with higher activator content. The experimental findings showed that the resistance of one-part geopolymer cement paste increases with comparatively greater activator content. However, raising the granular activator beyond 12 percent by fly ash weight decreases the strength and workability of the established one-part geopolymer cement. The optimum mix by weight of the fly ash was discovered to be 12 percent (i.e. 6 percent Na2O). At 28 days of curing, one-part alkali-activated paste recorded the greatest compressive strength of almost 50 MPa. The density of the one-part geopolymer paste is nearly the same regardless of the mixes. Microstructural assessment by FESEM, FTIR and XRD has shown that the established geopolymer paste includes quartz, pyrrhotite, aluminosilicate sodium and hydrate gels of calcium aluminosilicate. Based on the experimental information acquired, it can be deduced that the strength growth of one-part geopolymer cement is similar to that of Portland cement.
    Matched MeSH terms: Tensile Strength
  13. Jumaidin R, Khiruddin MAA, Asyul Sutan Saidi Z, Salit MS, Ilyas RA
    Int J Biol Macromol, 2020 Mar 01;146:746-755.
    PMID: 31730973 DOI: 10.1016/j.ijbiomac.2019.11.011
    Thermoplastic cassava starch (TPCS) is a promising alternative material to replace the non-biodegradable petroleum based polymer due to its good environmental-friendly aspect i.e. abundant, sustainable, recyclable and biodegradable in nature. However, TPCS have some limitation such as poor mechanical properties. Therefore, in the present study, cogon grass fibre (CGF) were incorporated into TPCS using compression molding. Then the fundamental properties of CFG/TPCS biopolymer composites were carried out in order to evaluate their potential as a biodegradable reinforcement. From the study it was found that, the incorporation of CFG has improved the tensile and flexural properties of the TPCS composites, while the impact strength and elongation were reduced. The thermal properties of the biocomposite were reduced as the cogon grass fibres increase from 0 to 5%. In term of morphological, SEM shows good fibre adhesion between CGF and TPCS. Soil burial test shows that incorporation of CGF into TPCS has slow down the biodegradation process of the composites. Thus, CGF/TPCS biopolymer composites can be classified as composites with great potential as environmental-friendly material that biodegradable and renewable.
    Matched MeSH terms: Tensile Strength
  14. Daood U, Sauro S, Pichika MR, Omar H, Liang Lin S, Fawzy AS
    Dent Mater, 2020 01;36(1):145-156.
    PMID: 31818524 DOI: 10.1016/j.dental.2019.11.003
    OBJECTIVE: To modify a universal dentine adhesive with different concentrations of riboflavin and D-Alpha 1000 Succinate polyethylene (VE-TPGS) as a chemical enhancer and to assess the micro-tensile bond strength (24h/12 months), determine resin penetration, measurement of intermolecular interactions and cytotoxicity.

    MATERIALS AND METHODS: An experimental adhesive system based on bis-GMA, HEMA and hydrophobic monomer was doped with RF0.125 (RF - Riboflavin) or RF/VE-TPGS (0.25/0.50) and submitted to μTBS evaluation. Resin dentine slabs were prepared and examined using SEM and TEM. Adhesion force was analysed on ends of AFM cantilevers deflection. Quenched peptide assays were performed using fluorescence scanner and wavelengths set to 320nm and 405nm. Cytotoxicity was assessed using human peripheral blood mononuclear cell line. Molecular docking studies were carried out using Schrödinger small-molecule drug discovery suite 2018-2. Data from viable cell results was analyzed using one-way ANOVA. Bond strength values were analysed by two-way ANOVA. Nonparametric results were analyzed using a Kruskal-Wallis test at a 0.05 significance level.

    RESULTS: RF/VE-TPGS0.25 groups showed highest bond strength results after 24-h storage in artificial saliva (p<0.05). RF/VE-TPGS0.50 groups showed increased bond strength after 12-months of ageing. RF/VE-TPGS modified adhesives showed appreciable presence of a hybrid layer. Packing fraction indicated solid angle profiles describing well sized density and topology relations for the RF/VE-TPGS adhesives, in particular with the RF/VE-TPGS0.50 specimens. Qualitative analysis of the phenotype of macrophages was prominently CD163+ in the RF/VE-TPGS0.50. Both the compounds showed favourable negative binding energies as expressed in terms of 'XP GScore'.

    CONCLUSION: New formulations based on the incorporation of RF/VE-TPGS in universal adhesives may be of significant potential in facilitating penetration, distribution and uptake of riboflavin within the dentine surface.

    Matched MeSH terms: Tensile Strength
  15. Sharip NS, Ariffin H, Andou Y, Shirosaki Y, Bahrin EK, Jawaid M, et al.
    Molecules, 2020 Sep 30;25(19).
    PMID: 33008017 DOI: 10.3390/molecules25194498
    Incorporation of nanocellulose could improve wear resistance of ultra-high molecular weight polyethylene (UHMWPE) for an artificial joint application. Yet, the extremely high melt viscosity of the polymer may constrict the mixing, leading to fillers agglomeration and poor mechanical properties. This study optimized the processing condition of UHMWPE/cellulose nanofiber (CNF) bionanocomposite fabrication in triple screw kneading extruder by using response surface methodology (RSM). The effect of the process parameters-temperature (150-190 °C), rotational speed (30-60 rpm), and mixing time (30-45 min)-on mechanical properties of the bionanocomposites was investigated. Homogenous filler distribution, as confirmed by scanning electron microscopy-energy dispersive spectroscopy (SEM-EDS) analysis, was obtained through the optimal processing condition of 150 °C, 60 rpm, and 45 min. The UHMWPE/CNF bionanocomposites exhibited improved mechanical properties in terms of Young's and flexural modulus by 11% and 19%, respectively, as compared to neat UHMWPE. An insignificant effect was observed when maleic anhydride-grafted-polyethylene (MAPE) was added as compatibilizer. The obtained results proved that homogenous compounding of high melt viscosity UHMWPE with CNF was feasible by optimizing the melt blending processing condition in triple screw kneading extruder, which resulted in improved stiffness, a contributing factor for wear resistance.
    Matched MeSH terms: Tensile Strength
  16. Olaiya NG, Nuryawan A, Oke PK, Khalil HPSA, Rizal S, Mogaji PB, et al.
    Polymers (Basel), 2020 Mar 05;12(3).
    PMID: 32151004 DOI: 10.3390/polym12030592
    The current research trend for excellent miscibility in polymer mixing is the use of plasticizers. The use of most plasticizers usually has some negative effects on the mechanical properties of the resulting composite and can sometimes make it toxic, which makes such polymers unsuitable for biomedical applications. This research focuses on the improvement of the miscibility of polymer composites using two-step mixing with a rheomixer and a mix extruder. Polylactic acid (PLA), chitin, and starch were produced after two-step mixing, using a compression molding method with decreasing composition variation (between 8% to 2%) of chitin and increasing starch content. A dynamic mechanical analysis (DMA) was used to study the mechanical behavior of the composite at various temperatures. The tensile strength, yield, elastic modulus, impact, morphology, and compatibility properties were also studied. The DMA results showed a glass transition temperature range of 50 °C to 100 °C for all samples, with a distinct peak value for the loss modulus and factor. The single distinct peak value meant the polymer blend was compatible. The storage and loss modulus increased with an increase in blending, while the loss factor decreased, indicating excellent compatibility and miscibility of the composite components. The mechanical properties of the samples improved compared to neat PLA. Small voids and immiscibility were noticed in the scanning electron microscopy images, and this was corroborated by X-ray diffraction graphs that showed an improvement in the crystalline nature of PLA with starch. Bioabsorption and toxicity tests showed compatibility with the rat system, which is similar to the human system.
    Matched MeSH terms: Tensile Strength
  17. Ojukwu M, Tan JS, Easa AM
    J Food Sci, 2020 Sep;85(9):2720-2727.
    PMID: 32776580 DOI: 10.1111/1750-3841.15357
    A process for enhancing textural and cooking properties of fresh rice flour-soy protein isolate noodles (RNS) to match those of yellow alkaline noodles (YAN) was developed by incorporating microbial transglutaminase (RNS-MTG), glucono-δ-lactone (RNS-GDL), and both MTG and GDL into the RNS noodles (RNS-COM). The formation of γ-glutamyl-lysine bonds in RNS-COM and RNS-MTG was shown by sodium dodecyl sulfate polyacrylamide gel electrophoresis. Scanning electron microscope showed that compared to others, the structure of RNS-COM was denser, smoother with extensive apparent interconnectivity of aggregates. The optimum cooking time was in the order: YAN > RNS-COM > RNS-MTG > RNS-GDL > RN (rice flour noodles); tensile strength was in the order: YAN > RNS-COM > RNS-MTG > RNS-GDL > RN; and elasticity were in the order: YAN > RNS-COM > RNS-MTG, RNS-GDL > RN. Overall, RNS-COM showed similar textural and structural breakdown parameters as compared to those of YAN. Changes in microstructures and improvement of RNS-COM in certain properties were likely due to enhanced crosslinking of proteins attributed to MTG- and GDL-induced cold gelation of proteins at reduced pH value. It is possible to use the combination of MTG and GDL to improve textural and mechanical properties of RNS comparable to those of YAN. PRACTICAL APPLICATION: Combined MTG and GDL yield rice flour noodles with improved textural properties. The restructured rice flour noodles have the potential to replace yellow alkaline noodles.
    Matched MeSH terms: Tensile Strength
  18. Xue Mei L, Mohammadi Nafchi A, Ghasemipour F, Mat Easa A, Jafarzadeh S, Al-Hassan AA
    Int J Biol Macromol, 2020 Dec 01;164:4603-4612.
    PMID: 32941902 DOI: 10.1016/j.ijbiomac.2020.09.082
    The development of intelligent packaging based on natural and biodegradable resources is getting more attention by researchers in recent years. The aim of this study was to develop and characterize a pH-sensitive films based on sago starch and incorporated with anthocyanin from torch ginger. The pH-sensitive films were fabricated by casting method with incorporation of different torch ginger extract (TGE) concentration. The surface morphology, physicochemical, barrier, and mechanical properties as well as the pH-sensitivity of films were investigated. The film with the highest concentration of TGE showed the lowest tensile strength (4.26 N/m2), toughness (2.54 MJ/m3), Young's modulus (73.96 MPa) and water vapour permeability (2.6 × 10-4 g·m/day·kPa·m2). However, its elongation at break (85.14%), moisture content (0.27%) and water solubility (37.92%) were the highest compared to other films. pH sensitivity analysis showed that the films containing TGE extract, changes in colour by changing the pH. The colour of films changed from pink to slightly green as the pH increased from pH 4 to 9. Thus, the developed pH-sensitive film with torch ginger extract has potential as intelligent packaging for detection of food freshness or spoilage to ensure their quality and safe consumption.
    Matched MeSH terms: Tensile Strength
  19. Ojukwu M, Ofoedu C, Seow EK, Easa AM
    J Sci Food Agric, 2021 Jul;101(9):3732-3741.
    PMID: 33301191 DOI: 10.1002/jsfa.11004
    BACKGROUND: Rice flour does not contain gluten and lacks cohesion and extensibility, which is responsible for the poor texture of rice noodles. Different technologies have been used to mitigate this challenge, including hydrothermal treatments of rice flour, direct addition of protein in noodles, use of additives such as hydrocolloids and alginates, and microbial transglutaminase (MTG). Recently, the inclusion of soy protein isolate (SPI), MTG, and glucono-δ-lactone (GDL) in the rice noodles system yielded rice noodles with improved texture and more compact microstructure, hence the need to optimize the addition of SPI, MTG, and GDL to make quality rice noodles.

    RESULTS: Numerical optimization showed that rice noodles prepared with SPI, 68.32 (g kg-1 of rice flour), MTG, 5.06 (g kg-1 of rice flour) and GDL, 5.0 (g kg-1 of rice flour) gave the best response variables; hardness (53.19 N), springiness (0.76), chewiness (20.28 J), tensile strength (60.35 kPa), and cooking time (5.15 min). The pH, sensory, and microstructure results showed that the optimized rice noodles had a more compact microstructure with fewer hollows, optimum pH for MTG action, and overall sensory panelists also showed the highest preference for the optimized formulation, compared to other samples selected from the numerical optimization and desirability tests.

    CONCLUSION: Optimization of the levels of SPI, MTG, and GDL yielded quality noodles with improved textural, mechanical, sensory, and microstructural properties. This was partly due to the favourable pH value of the optimized noodles that provided the most suitable conditions for MTG crosslinking and balanced electrostatic interaction of proteins. © 2020 Society of Chemical Industry.

    Matched MeSH terms: Tensile Strength
  20. Tan LF, Elaine E, Pui LP, Nyam KL, Yusof YA
    Acta Sci Pol Technol Aliment, 2021 1 16;20(1):55-66.
    PMID: 33449520 DOI: 10.17306/J.AFS.0771
    BACKGROUND: Biodegradable food packaging has improved in quality with recent research incorporating natural extracts for functionality purposes. This research aims to develop chitosan film with Chrysanthemum morifolium essential oil to improve the shelf life of fresh raw chicken and beef.

    METHODS: 1.5% (w/v) chitosan films with Chrysanthemum morifolium essential oil (0% to 6% (v/v)) were produced through homogenization, the casting of a film solution in a petri dish and convection drying. The edible film was evaluated in terms of its physical (color, thickness, water vapor permeability), mechanical (puncture strength, tensile strength, elongation at break) and chemical properties (antioxidant assay, Fourier Transform Infrared Spectroscopy (FTIR)).

    RESULTS: With an increasing concentration of Chrysanthemum morifolium in the chitosan film, the test values of physical properties such as tensile strength, puncture force, and elongation at break declined significantly. However, the thickness, water permeability, and color profile (L*, a*, b*) values of the chitosan film increased. Similarly, the scavenging effect of antioxidant assay increased (from 4.97% to 18.63%) with a rise in Chrysanthemum morifolium concentration. 2%, 3%, and 4% of Chrysanthemum morifolium in the chitosan film showed a significant inhibition zone ranging from 2.67 mm to 3.82 mm against Staphylococcus aureus, a spoilage bacterium that is commonly found in chicken and beef products. The storage and pH tests showed that 4% of Chrysanthemum morifolium in the film maintained pH level (safe to consume), and the shelf life was extended from 3 days to 5 days of meat storage.

    CONCLUSIONS: This study demonstrated that the incorporation of 4% (v/v) Chrysanthemum morifolium extract into 1.5% (w/v) chitosan film extends the storage duration of raw meat products noticeably by reducing Staphylococcus aureus activity. Therefore, it increases the quality of the edible film as an environmentally friendly food packaging material so that it can act as a substitute for the use of plastic bags. Future studies will be conducted on improving the tensile strength of the edible film to increase the feasibility of using it in the food industry. In addition, the microstructure and surface morphology of the edible film can be further determined.

    Matched MeSH terms: Tensile Strength
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