Textural properties of laksa noodle as affected by rice flour particle size

This study examined the physicochemical properties of rice flours with five different particle sizes (≤63, 80, 100, 125, and 140 μm) prepared by dry milling and their effects on textural properties of laksa noodles. Rice flour with the smallest particle size had the highest water absorption index, peak viscosity, hot paste viscosity, breakdown, final or cold paste viscosity and gel hardness, but the lowest gelatinization temperature. Reduction of rice flour particle size improved textural properties of laksa noodle. Laksa noodle produced from rice flour with the smallest particle size had the best textural properties

Chemical composition and DSC thermal properties of two species of Hylocereus cacti seed oil: hylocereus undatus and Hylocereus polyrhizus.

Two types of pitaya (Hylocereus cacti) seeds (Hylocereus undatus and Hylocereus polyrhizus) were investigated in this study. The fatty acid, phenolic, tocopherol, and sterol contents of the extracted seed oil were analysed. The results showed that the pitaya seeds contained a high amount of oil (18.33–28.37%). The three major fatty acids in the H. undatus seed oil (WFSO) and H. polyrhizus seed oil (RFSO) were linoleic, oleic, and palmitic acids. The total tocopherol contents in the WFSO and RFSO were 36.70 and 43.50 mg/100 g, respectively. The phytosterol compounds identified in the WFSO and RFSO were cholesterol, campesterol, stigmasterol, and β-sitosterol. Seven phenolic acid compounds were identified in the WFSO and RFSO, namely, gallic, vanillic, syringic, protocatechuic, p-hydroxybenzoic, p-coumaric, and caffeic acids. WFSO and RFSO can be differentiated by their Toff and Ton values in the DSC thermal curves. This study reveals that pitaya seed oil has a high level of functional lipids and can be used as a new source of essential oil

Development of instrumental methods for textural evaluation of chili paste

Chili shrimp paste (CSP) is a traditional Southeast Asian condiment. It is a semi solid suspension that contains chunky chili pieces. The textural characteristics of the paste are important quality parameters for most CSP lovers because they prefer pastes with a certain degree of thickness and chunkiness. Unfortunately, there is no standard methodology available to evaluate the textural properties of these pastes. Various samples of CSP were prepared and evaluated using sensory, texture analyzer and rheometer measurements. The results from instrumental evaluation were consistent and comparable to sensory data. Texture analysis using the back extrusion method (spherical probe and cylinder) was found to be suitable for textural quantification of CSP. The tan δ values measured using a vane-in-a–large-cup rheometer using an oscillation frequency sweep at 20 Hz correlated well with the sensory results, indicating that this method could effectively distinguish differences in CSP samples with different rheological properties . Both instrumental methods can be applied as quality control tools for CSP products

An investigation of liquid cooled air blower performance for laptop cooling system / Nicholas Pinenn and Jamilah Karim

This work presents a study on the performance of custom design laptop's cooling system. Differ from existing external cooling solution for laptop which blows slowly ambient air to the laptop's ventilation, this system lowers the ambient air temperature then blows it into the laptop's cooling box and increase its internal air pressure. The internal pressure then used to force the extra air flow into the laptop's ventilation port and into the laptop's internal cooling system. Several tests has been conduct in order to prove the reliability of the design system. The data obtained from the test are analyzed by using numerical method which the new cooling method is giving significant cooling. The cooling system demonstrated the liquid cooled air blower system gives up to 8 percent cooler than stock cooling system and 5 percent cooler when compared with existing on market cooling pad when the CPUs are in continuous stress test

Storage stability of spray-dried tilapia meat powder produced under optimized condition

In this study, gelation characteristics, colour, moisture and water activity of spray-dried tilapia powder (SDTP) packed in polyethylene pouches under aerobic conditions were evaluated under refrigerated, ambient and accelerated storage conditions for up to 90 days. The spray dried powder contained 2.63% moisture, had least gelation concentration (LGC) of 8.67% and water activity of 0.255. The L*, b* and a* values of spray-dried tilapia powder was found to be 97.69, 1.51 and 0.12, respectively. At refrigerated storage temperature (4°C), the LGC ranged between 8-10% up to 90 days (p0.05) when stored at 4°C and 10°C for up to 90 days The L value was found to decrease gradually (p<0.05) when stored at ambient and elevated temperatures and the most reduction was observed for the highest storage temperature of 60°C. The darkest powder with L* value of 85.4 was observed for powders stored at 60°C for 90 days. The moisture adsorption by SDTP was observed under refrigerated and ambient temperature, even though the value was still below 5% after 90 days of storage. However, under accelerated storage condition of 40°C and 60°C, the moisture content of the powder tends to decrease until 45 days and then slightly increased due to clumping of powder. Water activity also showed similar trend and lowest and highest value obtained was varied between 0.093-0.470. The half-life of the spray-dried tilapia powder kept at 10°C, ambient temperature and elevated temperature at 40°C were predicted to be approximately 14 months, 5 months and two and half months, respectively

Design of a pierce oscillator for CMOS SAW resonator

Development of microelectromechanical system (MEMS) based oscillators have drawn significant attention because it provides CMOS compatibility and multifrequency operations on a single chip. Recently, integrated MEMS resonators have shown great performance by attaining high quality factors and high frequency operations of up to the GHz range. Of interest, is fully integrated SAW resonator which can be connected to an oscillator circuit on the same chip. For oscillator circuit simulations, the CMOS SAW resonator was modeled using its RLC equivalent circuits. The insertion loss of CMOS SAW resonator used in this design is 35.8dB, with motional resistance Rx=8.95kΩ and the motional capacitance and inductance are Cx=199aF and Lx=350uH. For a MEMS resonator to be able to function as an oscillator it needs to be coupled with supporting circuits. There are various types of supporting oscillator circuit topologies namely the pierce oscillator, differential amplifier oscillator or the transimpedance amplifier circuit topology. The topology to be chosen depends on the design requirement, the loop gain of 1 and the zero phase shifts. For this work, the pierce circuit topology was chosen due to its simplicity and high frequency stability. This simple circuit comprising of 4 transistors, helps to achieve low power consumption and excellent phase noise characteristics. This paper will present the analysis, design and the simulation result of a high gain (>; 36dB) and low power pierce circuit topology for MEMS CMOS SAW resonator. The circuit was designed in 0.18um CMOS technology and yield open loop gain >; 36dB

Current reference pierce oscillator circuit topology for low phase noise MEMS SAW oscillator / Fazli Lut, Norlizawati Kamarudin and Jamilah Karim

This paper presents the design and simulation of a current reference Pierce oscillator circuit topology for microelectromechanical systems (MEMS) based oscillator. The designed amplifier achieves a gain of 33 dB at VDD of 1.2V. The amplifier core was tested with surface-acousticwave (SAW) resonators range from 800MHz to 2.4 GHz to form an oscillator and it shows a phase noise level range of -146 dBc/Hz to -151 dBc/Hz at 100 kHz offset frequency. This satisfies the maximum requirements phase noise of local oscillator (LO) of ultra-high frequency (UHF) for Bluetooth technology and Global System for Mobile Communications (GSM). The device produced a better figure-of-merit (FoM) when compared with other oscillators that were based on CMOS on-chip inductor and capacitor (CMOS LC), film bulk acoustic resonator (FBAR) and lateral-field-excited (LFE) Aluminium Nitride (AIN) contour mode resonators technologies. The oscillator circuit has been simulated using a 0.13µm CL130G CMOS technology process from Silterra (Malaysia) with the oscillator core consuming only 1.07mW DC power

Gm/ID approach for low power sustaining amplifier circuit for GHz range MEMS SAW oscillator

This paper presents the design and simulation of microelectromechanical system (MEMS) based oscillator based on CMOS MEMS surface acoustic wave (SAW) resonator and regulated cascode configuration (RGC) transimpedance amplifier (TIA). The proposed TIA is designed in a standard 0.18 μm Silterra CMOS prosess via Cadence Virtuoso software. Gm/ID technique is used to achieve higher gain and low power TIA. The simulation result shows that the voltage gain of the design circuit is 35.5dB and 2.08 GHz -3dB bandwidth. The circuit consume 1.6mW power at 1.8 V supply voltage. When integrate with 1.4GHz resonator, the phase noise of this oscillator is -105.27 dBc/Hz at 1kHz and -116.03 dBc/Hz 10kHz

Design and simulation of film bulk acoustic wave resonator (FBAR) gas sensor based on ZnO thin film

The interest in miniature device has led to the development of thin film bulk acoustic wave resonator (FBAR). The function of a resonator to gain a high resonant frequency value of an equipment make FBAR is suitable to act as sensor and filter for wide range of applications. The success of FBAR in providing a reduction of cost and power consumption make it an applicable device. It can be integrated with carbon nanotubes and oscillator circuit to enhance its performance as a gas sensor. Some of the chosen piezoelectric thin film are zinc oxide (ZnO) and aluminum nitride (AlN). This paper focuses on implementing FBAR as gas sensing application to monitor a person's health using breath analysis. The establishment of FBAR sensor to detect acetone gas as breath marker for diabetic disease through breath analysis is emphasize in this paper. A thin film FBAR is modelled using finite element simulation to evaluate its performances in term of coupling coefficient, sensitivity and resonance frequency. Zinc oxide was chosen as the piezoelectric thin film, aluminum as electrodes and silicon as substrate. FBAR sensor with ZnO thickness of 4.4 μ m demonstrated the highest coupling coefficient of 0.0643 at 472.65 MHz resonance frequency. The result is comparable to other previous works on FBAR sensor. Hence, this work indicates that FBAR has high potential for breath analysis. It can detect which type of gases exhaled by patient based on the different mass sensitivity value and different type of diseases can be identified

Quality and fortificant retention of rice noodles as affected by flour particle size

Rice noodles, which are widely consumed noodles in Southeast Asia, were evaluated as a potential carrier for fortificants such as vitamin A, folic acid, and iron. Because flour particle size was found to affect the noodle properties, this study was conducted to investigate the effect of five different particle sizes (≤63, 80, 100, 125, and 140 μm) of dry-milled rice flour on the cooking quality, microstructure, texture, and sensory characteristics of the rice noodles. The retention of fortificant in the noodles at every stage of processing as affected by the flour particle size was also determined. It was found that the rice noodles produced from flour with the smallest particle size studied (≤63 μm) had the best quality and were the most liked by the consumers. In addition, the noodles had the most compact and regular structure, which could be attributed to having the most severely gelatinized starch. This starch would have caused the least leaching of the fortificant into the surrounding water during the boiling stage of the rice noodle processing. Retention of iron in the cooked fortified rice noodles prepared from flour with the smallest particle size was high at around 87%, whereas that of vitamin A and folic acid were below 15%. Because the losses of the fortificant from the rice noodles were mostly owing to the boiling process, further improvements of the rice noodle processing conditions are required for reduction of the vitamin losses