Cryomechanical Freezing Of Keropok Lekor

The freezing process of keropok lekor (original fish sausage) has been studied experimentally and by numerical simulation of unsteady heat transfer the viability of using combined freezing process (called cryomechanical freezing), consisting of a two consecutive processes, an mime cryogenic freezer (using liquid N2 (LN)) followed by a continuous mechanical freezer as a preservation method was investigated The core temperature history of keropok lekor Immersed into cryogenic liquids or placed in the air-blast freezer was monitered till it reached -20°C The total time taken was 16 minutes for cryomechanical freezing and 21 minutes for mechanical freezing, which is calIed the freezing time The changes m sensory parameters (color, flavor, texture and overall accepatability) of keropok lekor as a result of cryomechanical freezing were also evaluated Keropok lekor made by the mechanization method With 21 ratio of fish meat to flour was used and were in cylindrical or spherical form The product was first submerged for 30s m LN2 and then immediately transferred to the air blast freezer for further freezing until the core temperature reached -20°C

Accelerated aqueous extraction and phytochemicals screening of eurycoma longifolia (Tongkat Ali) extract

The development of a rapid, robust and reliable method for extraction of plant materials is important for the screening of a wide range of plant bioactives and the discovery of biomarker. Accelerated aqueous extraction or commercially known as Accelerated Solvent Extraction (ASE) is an automated extraction technique operated at elevated temperatures and pressures to achieve extraction in a short period of time. The high temperature weakens the solute-matrix interactions and leads to a faster diffusion rate, better analyte solubility and lower solvent viscosity. This research was undertaken to evaluate the performance of an accelerated aqueous extraction of eurycomanone and other bioactive compounds from Tongkat Ali. Investigation was carried out to elucidate the effect of static cycle, static time and temperature on the content and degradation of eurycomanone. To date, there is no study being carried out on optimization of the extraction of eurycomanone from Tongkat Ali roots using this technique. The optimum operating conditions were subsequently used for the extraction of other phytochemicals. Response surface methodology was used to determine the significant operating conditions. The Box-Behnken design was implemented to maximize the response (eurycomanone content) from the resulted response surface. The extraction yield of eurycomanone are mainly affected by temperature (>100 oC) followed by the static time. A higher static time (>11 min) was found to cause eurycomanone degradation, while a lower temperature and static time reduced the extraction efficiency. The optimum conditions yielded a corresponding eurycomanone content of 9.21mg/g at static time of 8 minutes, static cycle of 5 and temperature of 90 oC. A liquid chromatography coupled with a triple quadrapole and time-of-flight, mass spectrometer (LC-QTOF-MS/MS) was used to profile the small metabolites. The major quassinoid identified were 13a(21)-epoxyeurycomanone, eurycomanone, longilactone14, 15ß-dihydroxyklaineanone, 6a-hydroxyeurycomalactone, eurycomalide B, laurycolactone A and laurycolactone B. In summary, the combination method of ASE and statistical analysis presented is an expedient technique for the phytochemicals screening of Tongkat Ali roots

Predicting freezing time for keropok lekor.

The freezing process of keropok lekor (fish sausage) has been studied experimentally and by numerical simulation of unsteady heat transfer. Core temperature history of keropok lekor samples placed in the air-blast freezer were registered. The developed numerical model utilizes the solution of the Fourier equation of heat transfer for an infinite cylinder and for a sphere with variable product enthalpy. Heat transfer coefficient was determined from the thermal history of aluminum cylinder with dimensions similar to experimental keropok lekor. The contents of water, crude protein, fat, carbohydrate and ash were determined to evaluate variations of keropok lekor thermal properties with temperature. These thermal properties, i.e, thermal conductivity, enthalpy freezing point, were obtained by using composition correlations. Calculated and experimental freezing times are in good agreement with each other, for each of the cylindrical and spherical keropok lekor samples. For 20 mm diameter cylindrical and spherical keropok lekor samples, the freezing time to achieve a frozen temperature of - 20°C were 20 min and 15 min, respectively

Compressibility and Dissolution Characteristics of Mixed Fruit Tablets Made from Guava and Pitaya Fruit Powders.

This study reports the tableting of whole fruit powder from pitaya and guava and their dissolution in relation to use as drink's tablets. Pulps of both fruits with peels and seeds were freeze-dried into powders with addition of 10% maltodextrin. The fruit powders, individually as well as in a binary mixture (1:1), were analyzed for material properties and were found to be poor in flow. Among the three powders, guava powder attained the lowest density during compaction and exhibited as a poor compressible powder. Mixed fruit tablets containing 1% effervescent agent eroded quite fast in all three types of solvents studied. However, the acidic solvent (0.1 N HCl) was found to be not suitable for erosion of tablets containing polyvinypolypyrrolidone (Kollidon CL). In terms of active ingredient release (antioxidant), Kollindon CL was found to be the best. In the case of color release (a⁎), the faster the erosion, the better was the color intensity irrespective of dissolution media. As drink tablets, the mixture containing 10% sugar was highly preferred by majority of panelists (80%). A month long storage study with the mixed fruit tablet formulation at room temperature showed good microbial stability

Optimisation of an effervescent pineapple tablet

This study is mainly undertaken to design and optimize an effervescent tablet formulation of Josapine pineapple by using the D-optimal experimental design methodology. Josapine pineapple powder, citric acid, sodium carbonate and stevia were used in the formulations as independent variables. Tablets were prepared by the direct compression method and evaluated for their disintegration time and sensory properties which were regarded as responses in a D-optimal design. Formulation V3 was selected as the optimum formulation with pineapple powder, citric acid, sodium carbonate and stevia at 49.59, 20.00, 11.96 and 18.45%, respectively. In addition, V3 has a very fast disintegration time and quite high overall acceptability which represents the consumer approval. The observed values of the responses obtained from the optimized formulation were very close to the predicted values where the euclidean distance calculated for V3 was equal to 0.26. In conclusion, this study reveals that the effervescent pineapple tablet has a wide potential for future development and can be enhanced for commercialization

Fabrication and performance of PSf/CA blend ultrafiltration membrane on effect of different polymer ratio

The study is focussed on the fabrication of various polysulfone/cellulose acetate (PSf/CA) polymer ratio with high polymer concentration of 20 wt. % via dry/wet phase inversion technique for membrane performances. These membranes were prepared by blending four different polysulfone/cellulose acetate ratios of 100/0, 90/10, 80/20 and 70/30 in a solvent, known as N-methyl-2-pyrrolidone (NMP). The effect of different polymer ratio on membrane characteristic are discussed in term of flux permeation, morphology, mechanical strength, fourier transform infrared spectroscopy (FTIR) analysis and flux recovery ratio (FRR). The increment of cellulose acetate composition resulted in different behaviours of membrane characteristic. The highest CA ratio (70/30) in PSf/CA composition obtained the highest flux permeation. Meanwhile, the flux recovery of 90/10 wt % membrane achieved the highest flux recovery, 59 % compared to 80/20 wt. % and 70/30 wt. % membranes with values of 12 % and 25 %, respectively. Interestingly, membrane with 80/20 wt. % observed an average improvement in flux permeation with a consistent increased. The formation of uniform finger-like voids in the sublayer of this membrane (80/20) encouraged a good mechanical strength for the membrane structure

LC-MS/MS-based metabolites of Eurycoma longifolia (Tongkat Ali) in Malaysia (Perak and Pahang).

A number of three LC–MS/MS hybrid systems (QTof, TripleTof and QTrap) has been used to profile small metabolites (m/z 100–1000) and to detect the targeted metabolites such as quassinoids, alkaloids, triterpene and biphenylneolignans from the aqueous extracts of Eurycoma longifolia. The metabolite profiles of small molecules showed four significant clusters in the principle component analysis for the aqueous extracts of E. longifolia, which had been collected from different geographical terrains (Perak and Pahang) and processed at different extraction temperatures (35 °C and 100 °C). A small peptide of leucine (m/z 679) and a new hydroxyl methyl β-carboline propionic acid have been identified to differentiate E. longifolia extracts that prepared at 35 °C and 100 °C, respectively. From the targeted metabolites identification, it was found that 3,4ɛ-dihydroeurycomanone (quassinoids) and eurylene (squalene-type triterpene) could only be detected in the Pahang extract, whereas canthin-6-one-3N-oxide could only be detected in the Perak extract. Overall, quassinoids were present in the highest concentration, particularly eurycomanone and its derivatives compared to the other groups of metabolites. However, the concentration of canthin-6-one and β-carboline alkaloids was significantly increased when the roots of the plant samples were extracted at 100 °C

Thin-layer drying model of Cosmos caudatus (C. caudatus)

Drying kinetic models and energy characteristics are well known as tools to evaluate and predict the most suitable drying physiochemical conditions for a particular product. In this study, a thin-layer drying model was developed to best describe the drying kinetic behaviour of Cosmos caudatus (C. caudatus). The drying experiments were conducted using a thermal convection oven and C. caudatus leaves were dried at five different temperatures (40, 50, 60, 70, 80°C). Six different thin-layer drying models were proposed and applied to select the best drying model by fitting to the experimental moisture ratio data. The proposed drying models included Page, Modified Page, Lewis, Henderson-Pabis, Two Term and Weibull and the results were statically compared and evaluated based on their goodness of fit. Among these, the Page model was found to best to represent the thin-layer drying behaviour of C. caudatus with 99.76 %, 5.93 x 10-5, 9.68 x 10-5 for the coefficients determination (R2), reduced chi-square (χ2), and root mean square error (RMSE), respectively. The average effective moisture diffusion coefficient (Deff) for the temperature 40 to 80°C ranged from 4.12 x 10-12 to 24.71 x10-12 m2/s, while the activation energy (Ea) was calculated at 39.35 kJ/mol based on the Arrhenius’s equation

Characterisation of fast dispersible fruit tablets made from green and ripe mango fruit powders

This study was performed to assess the compressibility and dissolution of binary fruit tablets prepared from whole green and ripe mango powder influenced by disintegrants. Mango powder was prepared by freeze-drying mango pulps. Green mango powder exhibited medium flow and was poorly compressible compared with ripe and mixed mango powders. Tabletting of powders was performed using a uniaxial die compaction machine and dissolution tester with a moving paddle for the dissolution study. Among five formulations, the tensile strength of the mixed tablets was higher than the individual and mixed-fruit tablets. The dissolution kinetics revealed that the dissolution rate of the mixed-fruit tablets was highly influenced by the disintegrant content. In conclusion, mixed mango tablets can be used as an effective vitamin C supplement if the formulation is optimised with balanced sweetness and acidity and can easily be consumed by chewing or by dissolving in water

Fabrication and performance of PSf/CA ultrafiltration membranes: effect of additives for fouling resistance and selective polyphenol removal from apple juice

This work focused on the addition of different pore formation-controlling agent to a polysulfone/cellulose acetate blend membrane via immersion precipitation using phase inversion technique to improve the fouling resistance and selective polyphenol removal of apple juice. The membranes were prepared by blending hydrophilic polyvinylpyrrolidone (PVP) and amphiphilic Pluronic F127 (Plu) with polysulfone/cellulose acetate matrix in N-methyl-2-pyrrolidone. The morphology, mechanical strength, flux permeation, flux recovery ratio, and polyphenol separation of these membranes were characterized. It was found that the fabricated membranes with addition of PVP and Plu were more effective than the membrane without a pore formation-controlling agent. The flux recovery of the membranes with combined pore formers after ultrafiltration of bovine serum albumin increased from 12.4% to 66.9%. The selectivity of polyphenols increased from 6% to 79% with an improved flux recovery of 79%, which shows the reduction of yellowish-brown pigment in apple juice