Yus Aniza Yusof

Physicochemical and nutritional properties of spray-dried pitaya fruit powder as natural colorant

Pitaya commonly known as dragon fruit is very popular of its intense color, constituent minerals, vitamins, and antioxidant properties. In this study, physiochemical properties of whole pitaya fruit powder as influenced by 2 different maltodextrin concentrations (20 and 30%) and 4 different inlet temperatures (145, 155, 165, and 175°C) were carried out. As inlet temperature increased moisture content and water activity decreased and this change was apparent at high concentration of maltodextrin. The best spray drying condition in relation to betacyanin content was 155°C inlet temperature and 20% maltodextrin concentration. Concerning the flowability, all factors and their levels resulted in poor flowing powder. From nutritional point of view, pitaya fruit powder was found rich in protein, fat, ash, fiber, and antioxidant. This study indicated that the pitaya fruit powder produced from whole pitaya fruit has potential to use as natural coloring agent and a health supplement.

Extractive fermentation for improved production and recovery of lipase derived from Burkholderia cepacia using a thermoseparating polymer in aqueous two-phase systems

An extractive fermentation technique was developed using a thermoseparating reagent to form a two-phase system for simultaneous cell cultivation and downstream processing of extracellular Burkholderia cepacia lipase. A 10% (w/w) solution of ethylene oxide-propylene oxide (EOPO) with a molecular mass of 3900 g/mol and pH 8.5, a 200 rpm speed, and 30 °C were selected as the optimal conditions for lipase production (55 U/ml). Repetitive batch fermentation was performed by continuous replacement of the top phase every 24h, which resulted in an average cell growth mass of 4.7 g/L for 10 extractive batches over 240 h. In scaling-up the process, a bench-scale bioreactor was tested under the conditions that had been optimized in flasks. The production rate and recovery yield were higher in the bioreactor compared to fermentation performed in flasks.

Extraction of Total Phenolic Content from Garcinia mangostana Linn. hull. I. Effects of Solvents and UV–Vis Spectrophotometer Absorbance Method

The effect of solvents with different polarity on the extraction of total phenolic content from mangosteen hull was investigated. The Folin–Ciocalteu (FC) method, expressed in equivalent to gallic acid concentration was used to quantify total phenolic content. Methanol was the most effective solvent in giving the highest recovery (p < 0.05) of phenolic compounds, compared to ethanol, acetone, isopropanol, ethyl acetate and distilled water. Regression analysis was performed to evaluate the relationship between the direct absorbance method and the FC method for total phenolic contents determination. Strong coefficients of determinations (R2 ≥ 0.990) were obtained for the absorbance of acetone, ethanol, and methanol extracts suggesting the regression equations obtained can be used to determine the total phenolic contents without using the FC method.

Modelling the effect of temperature on respiration rate of fresh cut papaya (Carica papaya L.) fruits

A respiration rate (RR) model based on Peleg’s equation was developed for predicting RRs of fresh cut papaya. Respiration data for fresh cut papaya at 3/4 maturity were generated at temperatures 5, 10, 15, 20, 25 and 30°C using a closed system. RRs was found to be significantly influenced by storage temperature and increased from 0.021 to 0.289 mL[O2]/kg·h and 0.063 to 0.393 mL[CO2]/kg·h as a function of O2 and CO2 gas concentrations, respectively. Peleg’s constant K1 and K2 were obtained from linear regression analysis using GraphPad Prism 5.0 software and regression coefficients have good fit with values close to unity. The model was verified to assess the capability of its predictability of the RRs over the temperatures. There was good agreement with the experimentally estimated RRs. Information derived from the model can contribute in the design of successful modified atmospheric systems for storage of fresh cut papaya.

Classification of entomological origin of honey based on its physicochemical and antioxidant properties

ABSTRACT Physicochemical and antioxidant properties of raw honeys from Malaysia were used as markers for determining its entomological source of bee species of Apis dorsata, Apis mellifera, Apis cerana, or Heterotrigona itama. Physicochemical properties of moisture content, water activity, specific gravity, viscosity, pH, free acidity, electrical conductivity, colour (L*, a* and b*), colour intensity, and antioxidant properties including the DPPH free radical scavenging activity power (1/IC50), ascorbic acid equivalent antioxidant content (AEAC), ferric ion reducing antioxidant power (FRAP), and total phenolic content (TPC) were measured and analysed. Honeys were classified into two major groups of those from honey bees (Apis spp.) and Trigona stingless bees (Heterotrigona itama) from its physicochemical and antioxidant properties using hierarchical cluster and principal component analyses. The Kelulut honey produced by stingless bees, Heterotrigona itama was differentiable from honeys from the regular honey bee species, the Apis spp. with characteristics of high moisture content of 33.24 g/100 g, free acidity of 136.8 meq/kg, colour intensity of 990.3 mAU, AEAC of 26.64 mg/100 g, and FRAP of 41.95 mg AAE/100 g. Honey classification by its entomological origin helps in honey identification and it reduces honey fraudulence.

Effect of Processing on Instrumental Textural Properties of Traditional Dodol Using Back Extrusion

Textural properties of traditional dodol were investigated using the back extrusion method with a texture analyzer. The effects of cooking time, sugar content, and temperature on dodol instrumental textural attributes, including firmness, consistency, cohesiveness, and index of viscosity, were found to be significantly (P < 0.0001) affected by all the factors. Increase of cooking time in the range of 2.00 to 2.75 h and increase of sugar level in formulation from 1.0 to 1.3 kg/kg glutinous rice flour resulted in an increase of dodol firmness, consistency, cohesiveness, and index of viscosity. Temperature increase from 40 to 65°C, however, resulted in the decrease in all the evaluated properties of dodol. The analysis of variance produced a significant difference in all the textural attributes with R2 > 89% except for the effect of sugar on index of viscosity. The physicochemical properties of commercial dodol including proximate analysis and textural attributes were also reported.

A Comparison of the Direct Compression Characteristics of Andrographis paniculata, Eurycoma longifolia Jack, and Orthosiphon stamineus Extracts for Tablet Development

Tropical herb extracts, such as Andrographis paniculata, Eurycoma longifolia Jack and Orthosiphon stamineus, which have enormous beneficial health effects need to be made available in a convenient and affordable tablet form. Information on the powder extract characteristics during compression is lacking and would be useful in investigations of powder deformability for optimizing operating conditions. The current market value of herbal products for traditional and complementary medicine is estimated to be between USD 40 to 100 billion with an average growth rate of 15 to 20% each year (Abdul Aziz et al., 2004). Andrographis paniculata (locally known as ‘hempedu bumi’ or ‘akar cerita’) has analgesic, anti-malaria, anti-inflammatory, anti-neoplastic, anti-ulcerogenic, anti-bacterial, febrifuge, anti-platelet, anti-diarrhoeal anti-thrombotic, anti-diabetic, and anti-hypertensive properties (Ahmad and Asmawi, 1993). The roots of Eurycoma longifolia Jack are traditionally used for curing fever, mouth ulcers, and intestinal worms, and as a general tonic after childbirth, and are believed to be effective for treating hypertension and malaria. Studies have shown that Eurycoma longifolia Jack possesses sexual enhancement and aphrodisiac properties (Sambandan et al., 2006). Orthosiphon stamineus, or ‘misai kucing’, has also been scientifically proven to have anti-hypertensive, anti-inflammatory, and diuretic properties, and has also been proven to be beneficial for urinary tract ailments, renal stones, arteriosclerosis, nephritis, diabetes mellitus, hypertension, rheumatism, tonsillitis, and menstrual disorders (Jagarath and Ng, 2000). Currently, Orthosiphon stamineus is categorized as one of the herbs with a great potential for commercialization in Malaysia due to its easy cultivation and its validated health benefits, particularly in treating ailments associated with the kidney and urinary system (Jagarath and Ng, 2000). Most of the research conducted on these herbs so far has been limited to their chemical and medicinal properties. This work attempted to obtain scientific and engineering data to determine the technical feasibility and economic viability of producing solid oral dosage

The influence of operational parameters and feed preparation in a convective batch ribbon powder mixer

Purpose To investigate the effect of feed preparation characteristics and operational parameters on mixing homogeneity in a convective batch ribbon mixer. Methods Lactose 100M, lactose 200M, ascorbic acid, and zinc oxide powders were used for the mixing study. Operational parameters studied were rotational speed and mixing time. The feed preparations studied were the use of preblending and the particle size of the feed materials. The blends of ascorbic acid, zinc oxide, and lactose were prepared with preblending and without preblending, prior to mixing at different blender rotation speeds and mixing times. Chemical tests were performed to measure the homogeneity of the ascorbic acid in the model mixture. Results With preblending, a mixture with lactose 200M achieved the required homogeneity in a shorter period of time at a lower rotational speed. Conclusion The results indicated that the homogeneity of the mixtures was influenced by the blender rotation speed and mixing time. Better mixing can be obtained with higher rotation speeds and longer mixing time. It was also observed that preblending and smaller feed particle size achieved the required homogeneity in a shorter period of time at a lower rotational speed. These results illustrate that using binders with a smaller particle size and a preblending technique improves the mixing process in a convective batch ribbon powder mixer. However, prolonged periods of high-speed mixing will lead to mixture segregation.

Prediction of Physicochemical Properties of Pummelo Juice Concentrates as a Function of Temperature and Concentration

The properties of pummelo juice were studied by measuring its chemical and physical composition. Pummelo fruit juice was freeze-concentrated to a concentration varying from 10 to 50 °Brix for investigation at temperature ranging from 6 to 75 °C. The fresh pummelo juice compositions in terms of moisture content, ash, fat, protein, fibre, carbohydrates, and vitamin C are comparable to existing literature. The water activity, pH and acidity were predictable linearly by its concentration measured in °Brix. The density of pummelo juice was well-predicted using linear regressions with a single parameter (i.e., concentration), giving R2>0.983 and with a temperature at R2>0.921. The density of pummelo juice showed stronger dependence on its concentration than on the temperature. With multiple linear regressions, the density could be predicted by the equation, with an R2 of 0.9877. As such, these predictions are useful in the juice processing industry as densities variant by concentration and temperature are important during the pasteurization process.

Structural and functional properties of pectin extracted from jackfruit (Artocarpus heterophyllus) waste: Effects of drying

ABSTRACT Pectin extracted from jackfruit waste was dried using different drying techniques, and the chemical composition and structure, flowability, appearance, solubility, and flow behaviour of the dried materials were determined. Yield, galacturonic acid content, and the degree of esterification were found within the ranges of 7–11, 62–68, and 59–66%, respectively, for freeze-dried, spray-dried, vacuum oven-dried, and oven-dried pectin samples from jackfruit waste. Fourier transform infrared spectral analysis showed no major structural differences in the pectin samples produced by the various drying techniques, and their surface structures were comparable to those of analytical and food pectin. The drying methods did not significantly affect the chemical composition (p > 0.05) but did significantly affect the physical appearance, viscosity, and solubility of jackfruit waste pectin (p < 0.05).