Utilization of palm kernel expeller (PKE), a palm oil milling by-product, may be diversified through the exploitation of its protein component. The PKE protein could be effectively extracted using an alkaline
solution and followed by enzymatic hydrolysis to produce PKE protein hydrolysates or crude PKE peptide. The extraction of PKE protein was successfully carried out using an alkaline solution at pH11, at ratio of 1:10 (g/ml), PKE powder to alkaline solution with continuous shaking, 150 rpm, in a water bath operating at 50°C for 30 min. The extracted protein powder (PKEP) had 68.50±3.08% crude protein, 0.54±0.03% fat and 0.73±0.02% ash. The freeze-dried PKEP was re-suspend in particular buffer and hydrolyzed with proteolytic enzymes (Alcalase® 2.4L, Flavourzyme® 500MG, pepsin or trypsin) to obtain PKEP hydrolysate (PKEPH). The effect of enzyme concentration (0, 2, 4, 6, 8 & 10%) and time of hydrolysis (0, 6, 12, 24, 48 h) was studied to determine the most efficient hydrolytic conditions. Results showed that all enzymes tested were capable of hydrolyzing the PKEP and producing hydrolysates with different degree of hydrolysis (DH%). At 8.0% concentration, Alcalase®2.4L hydrolyzed PKEP into the highest DH (75.96%) hydrolysate (PKEPH) after 1h hydrolysis. Although only with 2.0% Alcalase 2.4 L concentration, it was sufficient to produce PKEP hydrolysate of 81.35% DH %, but it required 12 h to hydrolyze the protein. Pepsin was relatively the least efficient protease to hydrolyze the PKEP.
Starch is a biodegradable polymer produced in abundance from many renewable resources. This study examined the influence of citric acid (0-40% w/wt%) ) and water (0-40% w/wt%) as secondary additive and glycerol as plasticizer on the mechanical properties of bio-plastic starch (BPS) from Malaysian sago. The CA content varies from 0 to 40 w/wt% while water was also varied from 0 to 40 w/wt%. FT-IR spectroscopy showed that acid citric improve the properties of BPS and water give negative effects to the carbon hydrogenbond. It is obvious that the addition of the CA at 30 wt/wt% improve the mechanical property of BPS to more than 40% compare to the addition of water.
The aim of this study was to produce a high-protein, wet yellow noodle by the incorporation of surimi powder as a protein source and evaluate the effects of the physicochemical and sensory properties of the
noodle. The surimi powder was prepared by oven drying the wet surimi at 60oC until the moisture content was below 10%. Five concentration levels of surimi powder substitutions were used (0, 5, 10, 15 and 20%), and as a result, the noodles showed a trend that significantly increased (P
Legume is a plant in the family of Fabacae or Leguminosae that rich in protein, carbohydrate, dietary fibre, and minerals. Germination of legume causes some important changes in the biochemical and a nutritional characteristic of the legumes that may be beneficial to human’s health and nutritional status. This study was carried out to determine the effect of germination on total phenolic, tannin and phytic acid contents of soy beans and peanut. The process of germination was carried out by soaking legumes in water for 6 hours, followed by germinating them in wet muslin cloth for 48 hours. After germination, samples were dried and stored in refrigerator before analysis. Total phenolic, tannin and phytic acid were determined spectrophotometrically. Total phenolic contents were decreased significantly (p
The effects of orange sweet potato flour addition to tapioca starch on the expansion, oil absorption,
bulk density, water absorption index (WAI), water solubility index (WSI), hardness and colour of fried extruded fish crackers were investigated. The microstructure properties were assessed by Field Emission Scanning Electron Microscope (FESEM) and the sensory properties of fried extruded fish crackers were determined by quantitative descriptive analysis method. The shape and texture of the product were similar to that of normal breakfast cereal. Light brownish and slightly harder texture was obtained with addition of orange sweet potato flour to tapioca starch in the fried extruded fish crackers. The bulk density and water solubility index (WSI) increased with the increase in orange sweet potato flour addition. However, water absorption index (WAI), linear expansion, expansion ratio, volume expansion and oil absorption decreased as the amount of orange sweet potato increased. The microstructure studies revealed that fried extruded fish crackers with high percentage of orange sweet potato flour had small air cells and thick cell wall. The fried extruded fish crackers with 30% fish, 14% orange sweet potato flour and 56% tapioca starch had high crispiness score and accepted by the trained panellists.
Garlic has been a favorite additive in food for many years in various cultures. It is known that garlic
(Allium sativum) possesses antimicrobial, antiprotozoal, antimutagenic, antiplatelet and antihyperlipidemic
properties. Allicin, a thiosulfinate extract of garlic, has been presumed to be a very strong antioxidant. High performance liquid chromatography (HPLC) analysis of raw garlic extract was not conclusive to determine allicin’s presence. However, using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) scavenging methods to determine the antioxidant activity of raw garlic extract shows a color change from deep violet to yellow, indicating antioxidant activity. Thus, raw garlic can be a source of antioxidant based on the results of the DPPH scavenging analysis.
Diseases such as diabetes mellitus and gout are among the chronic diseases affecting worldwide population. Investigation is required to find the alternative approaches to treat these chronic diseases, such as plant based medicine. In this study, lemongrass (Cymbopogan citratus) was chosen and examined on the basis of their usage in traditional medicines throughout Southeast Asia. GCMS analysis revealed the major constituents of the lemongrass essential oil which compromise 67.769% and 67.328% of the total oil respectively. Total phenolic content of the essential oil was analyzed by Folin Ciocalteau method and the results indicated that highest amount of phenolic content was obtained from essential oil extracted from lemongrasses stalk, with phenolic concentration of 2100.769 mg/l GAE. Anti oxidant activity was examined by DPPH scavenging test and the highest inhibition was obtained by essential oil extracted from lemongrass stalk (89.5%). β-glucosidase inhibition assay was carried out using an in-vitro model for anti diabetic test and lemongrass stalk essential oil showed highest degree of inhibitory activity (89.63%). Anti gout test was examined by xanthine oxidase inhibition (XOI) assay with the maximum percentage of xanthine oxidase inhibition of 81.34% obtained from lemongrass stalk essential oil.
The present study was carried out to characterize red fruit (Pandanus conoideus Lam) oil (RFO) in term of FTIR spectra, fatty acid composition, and volatile compounds. FTIR spectrum of RFO was slightly
different from other common vegetable oils and animal fats, in which in the frequency range of 1750 – 1700 cm-1, RFO appear two bands. The main fatty acid composition of RFO is oleic acid accounting for 68.80% followed by linoleic acid with the concentration of 8.49%. The main volatile compounds of RFO as determined using gas chromatography coupled with mass spectrometry (GC-MS) and headspace analyser are 1,3-dimethylbenzene (27.46%), N-glycyl- L-alanine (17.36%), trichloromethane (15.22%), and ethane (11.43%).
Rheology is the science of deformation and flow behavior of fluid. Knowledge of rheological properties of fluid foods and their variation with temperature and concentration have been globally important for industrialization of food technology for quality, understanding the texture, process engineering application, correlation with sensory evaluation, designing of transport system , equipment design (heat exchanger and evaporator ), deciding pump capacity and power requirement for mixing. The aim of this study was to determine the rheological behavior of pomelo juice at different concentrations (20-60.4%) and temperatures (23-60°C) by using a rotational rotational Haake Rheostress 600 rheometer. Pomelo juice was found to exhibit both Newtonian and Non-Newtonian behavior. For lower concentration the Newtonian behavior is observed while at higher concentration Non-Newtonian behavior was observed. Standard error (SE) method was selected on the basis to carry out the error analysis due to the best fit model. For the four models the values of SE show that the Herschel-Bulkley and Power Law models perform better than the Bingham and Casson models but Herschel-Bulkley model is true at higher concentration. The rheological model of pomelo juice, incorporating the effects of concentration and temperature was developed. The master-curve was investigated for comparing data from different products at a reference temperature of 40°C. Multiple regression analysis indicated Master-Curve presents good agreement for pomelo juice at all concentrations studied with R2>0.8.
MeSH terms: Industrial Development; Equipment Design; Food Technology; Hot Temperature; Regression Analysis; Rheology; Temperature
Foreign bodies in packaged foods may pose both a safety risk and a risk of perceived degradation of
quality. When food products are manufactured or packaged, small foreign objects might end up in the product. It is naturally desirable for the food industry that all foreign bodies are detected and removed before they reach customers. In this study, the ultrasonic method was used to detect the foreign bodies in canned foods. In order to establish a technical concept for the detection of foreign bodies in canned foods, an experimental investigation was carried out using pulse-echo ultrasonic testing. A number of simulated foreign object pieces were deliberately put inside the canned food and the results were analyzed. The approach demonstrates that ultrasound has potential for application in many industrial food packaging environments where foreign objects need to be detected. Indeed, detection up to 4 millimeter foreign body size has been done for rock and metal foreign bodies.
Characterization and quantification of carotenoid compound is complicated, costly and timeconsuming. The accuracy and reliability of the data depend solely on the standard and to High Performance Liquid Chromatography (HPLC) analysis but the major constraint is to acquire and to maintain the pure standards. Carotenoid standards are commercially available but they are expensive and are prone to isomerization and oxidation. Thus, the purpose of this study is to establish an analytical method for isolating β-carotene by using open column chromatography (OCC) from pumpkin (Cucurbita moschata) to be used as one of the carotenoid standards for determination of total and individual carotenoid. Pumpkin with orange flesh has been chosen due to the non-seasonal nature and its availability all year-round. This study demonstrated that the purity of β-carotene standard; determined by HPLC was ranged from 92.21 to 97.95%. The standard curves with five different concentrations of β-carotene extract from pumpkins in triplicate were constructed by plotting the peak area against the concentration. The coefficient of correlation was 0.9936. Therefore, this study established that pumpkin can be a reliable source of beta-carotene standard as it is cheap and commonly available throughout the year.
MeSH terms: Carotenoids; Chromatography, High Pressure Liquid; Isomerism; Maintenance; Reference Standards; Seasons; Reproducibility of Results; beta Carotene; Cucurbita; Citrus sinensis
Ulam or traditional vegetables in Malaysia comprise more than 120 species representing various
families ranging from groundcovers, shrubs to trees. The leaves, shoots, flowers, fruits, roots and rhizomes of the vegetables are eaten fresh as salad or cooked and are consumed to add variety and flavor to the diet, as well as for their health benefits. Ulam species are rich in carbohydrate, protein, mineral and vitamin. This study established that ulam species differ greatly with respect to types and concentrations of carotenoids in leaves. A total of 10 species were evaluated for quantitative and qualitative carotenoid composition through spectrophotometry and HPLC analysis. The main carotenoids identified in these selected ulam were lutein, neoxanthin, violaxanthin, zeaxanthin and β-carotene. The ratio of these carotenoids varies between species.
Response Surface Methodology (RSM) with Central Composite Rotatable Design (CCRD) was performed in this study to develop an acceptable reduced calorie chocolate cake. The range of the independent variables, namely Jackfruit Seed (JFS) flour (20-25% replacement of wheat flour) and polydextrose (10-15% replacement of sucrose) were identified which affect the volume, specific volume, symmetry and uniformity of the chocolate cake. The coefficient of determination, R2 values for volume, specific volume, symmetry and uniformity were greater than 0.900. The optimum level for replacement of sugar with polydextrose was at 11% and wheat flour with JFS flour was at 16% with calorie reduction approximately 34% from the control cake formulation.
Supercritical carbon dioxide extraction (SC-CO2) of bioactive flavonoid from Strobilanthes crispus (Pecah Kaca) was performed to study the effects of various parameters such as pressure, temperature and dynamic extraction time on the yield and composition of bioactive flavonoid. The results were also compared with those obtained by conventional Soxhlet extraction in lab conditions. The results from SFE showed that the effect of extraction variables on extraction yields decreased in the following order: pressure, temperature and dynamic extraction time. The extraction pressure played a dominant role in the yield of the sample while the effect of time could be ignored. This study also revealed that both Soxhlet extraction and SC-CO2 extraction can be used to obtain flavonoid compound. Under the optimum conditions, the highest bioactive flavonoid compound content was obtained at 3.98% and eight flavonoid compounds were identified by HPLC.
The production of bioprotein by coconut dregs is found to be a novel and cheaper carbon source.
Media optimization for bioprotein production from coconut dregs through solid state fermentation has been developed as a one of the approaches to increase the protein production. The utilization of these coconut dregs provides as alternative substrates and also helps in solving waste disposal problems. Among the seven media components, only NH4NO3, MgSO4.7H2O and CuSO4.5H2O were found to be significantly affecting the bioprotein production.
This work aims at optimizing the media constituents for citric acid production from oil palm empty fruit bunches (EFB) as renewable resource using artificial neural networks (ANN) approach. The bioconversion process was done through solid state bioconversion using Aspergillus niger. ANN model was built using MATLAB software. A dataset consists of 20 runs from our previous work was used to develop ANN. The predictive and generalization ability of ANN and the results of RSM were compared. The determination coefficients (R2-value) for ANN and RSM models were 0.997 and 0.985, respectively, indicating the superiority of ANN in capturing the non-linear behavior of the system. Validation process was done and the maximum citric acid production (147.74 g/kg-EFB) was achieved using the optimal solution from ANN which consists of 6.1% sucrose, 9.2% mineral solution and 15.0% inoculum.
The addition of ribose to minced chicken or minced pork followed by heating at 95oC yielded minced
meat with different pH, colour (CIE L*, b*) and absorbance values that can be used as indicators for species differentiation. The higher intensity of the Maillard reaction parameters in minced chicken was due to the higher protein and lysine contents, and the presence of more water-soluble proteins within the minced chicken during heating. Cluster analysis using Maillard reaction parameters showed that the two types of minced meat could be classified into two different groups. A confidence interval (95% confidence) analysis revealed that the absorbance, CIE L* values, and CIE b* values could be used as indicators for differentiation between the two types of minced meat, as the intervals between these Maillard reaction parameters for the two minced meats were far apart.
This study was undertaken to characterize the antibiotic resistance and randomly amplified polymorphic DNA (RAPD) profiles of Vibrio parahaemolyticus isolates from raw vegetable samples. A total of 46 isolates of V. parahaemolyticus recovered from raw vegetables samples and were confirmed by PCR were analyzed in this study. Most of the isolates were resistant to nalidixic acid (93.48%) and were the least resistant towards imipinem (4.35%). The MAR index results also demonstrated high individual and multiple resistances to antibiotics among the isolates. From the RAPD analysis, the size for RAPD fragments generated ranged from 250 bp to 1,500 bp, with most of the strains contained three major gene fragments of 350, 1,000 and 1,350 bp. The RAPD profiles revealed a high level of DNA sequence diversity within the isolates. Antibiotic resistance and RAPD proved to be effective tools in characterizing and differentiating the V. parahaemolyticus strains.
MeSH terms: Anti-Bacterial Agents; Base Sequence; DNA; Drug Resistance, Microbial; Nalidixic Acid; Vegetables; Vibrio parahaemolyticus; Polymerase Chain Reaction; Random Amplified Polymorphic DNA Technique
The main source of E. coli 0157:H7 is cattle, but recent studies showed high percentage of outbreaks
contributed by contaminated water. The occurrence of E. coli O157:H7 in environmental water samples poses a potential threat to human health. The aim of this study was to establish a protocol for the detection of the pathogen E. coli O157:H7 and E. coli virulence genes (eaeA, rfbE, hly, stx1, and stx2) in a multiplex PCR protocol using six specific primer pairs. The target genes produced species-specific amplicons at 625 bp, 397 bp, 296 bp, 166 bp, 210 bp and 484 bp for E. coli O157:H7 (fliCh7 gene) and virulence genes (eaeA, rfbE, hly, stx1, and stx2) respectively. The results obtained show that the established PCR protocol is suitable for a rapid and specific analysis of the pathogenic E. coli O157:H7 in environmental water samples for the assessment of microbiological risks.
Media components such as wheat flour, MgSO4 and particle size were screened by Placket Burman design (PBD) while the operating range was fixed by one-factor-at-a-time method (OFAT), primarily for the enrichment of cassava peels as animal feed. Optimization of the selected media components was carried out using Face–Centered Central Composite Design (FCCCD) of the Response Surface Methodology (RSM) and the responses were measured in term of protein and lignin contents. Statistical analysis of the result showed that the quadratic term of wheat flour and the interaction between wheat flour and particle size were highly significant (P