Proximate, functional and pasting properties of a new variety of sweet potato, VitAto, flour, known for its high vitamin A contents, were compared with two other commercial sweet potatoes, Bukit Naga and Okinawan, flour available in Malaysia. The recoveries of each sweet potato from milling were not significantly different at about 20% but in proximate analysis, the VitAto presented the highest protein (5.7%) and dietary fiber (14.8%) contents with more energy 399.6 kcal/100 g produced. The VitAto flour has average particle size of 132.04 μm. The pasting temperature of the VitAto flour was 65oC, with highest setback and trough viscosity values of 530.90 and 197.20 mPa.s, respectively. The flour is classified as easy flowing and stable powders. This study provides information which helps in the handling, packing and storage of sweet potato flours. It also shows that the VitAto flour has an array of functional, pasting and proximate properties that can facilitate its uses in many areas with better nutritional properties.
The advantage of cooking cannot be summarized just as the better food digestion. Some investigations showed the effect of cooking on reduction of food anti-nutrients such as oxalate. This study was aimed to determine the effect of cooking on oxalate content and its negative effects on calcium availability in eight Malaysian soy-based dishes. Since there is few data which examined the effects of cooking on food oxalate content globally, thus this study was designed as the first in Malaysia. Oxalate in this research was analyzed by using enzymatic methods, while calcium content was determined by using Atomic Absorption Spectrophotometer. The oxalate concentration was in the range of 6.43-19.40 mg/100 g for whole cooked samples, 9.03-11.90 mg/100 g for raw soy products, and 4.36-7.99 mg/100 g for cooked ones. There were 5 out of 12 samples containing oxalate, which was significantly lower (p < 0.05) in cooked products compared to the raw ones. The rest of the samples were also lower in oxalate but not significantly different (p > 0.05). Oxalate in raw/cooked fermented soy products (tempeh) was slightly lower compared to the non-fermented ones. However, there was no significant difference (p > 0.05) in oxalate amount between fermented and non-fermented soy products. As Oxalate/Calcium ratio was below 1, oxalate did not have an effect on availability of calcium in the studied samples. Optimal cooking and food processing might be effective in reducing oxalate content in soy products. There is a need for more investigations about the effect of cooking on soy products to confirm the present results.
Diacylglycerol at 1 or 6% was added into refined bleached and deodorized palm oil (RBDPO) and crystallized from the melt in a thermally controlled water bath at 22°C for 90 min. Slurries were withdrawn after 5, 15, 30, 60 and 90 min of crystallization for solid fat content (SFC) and crystal morphology studies. Crystallization was also performed in a similar manner using a Labmax reactor connected to a FBRM detector to obtain the information on crystal count and size distribution during crystallization. SFC of the slurries increased with increase in crystallization time up to a certain level followed by a plateau. SFC of RBDPO added with DAG was also higher with the increase in percentage of DAG added and no induction time was observed to initiate crystallization in RBDPO added with DAG. The addition of DAG caused rapid crystallization of RBDPO as observed by enhance nucleation and larger crystal size with increase in the percentages of DAG added.
The aim of this study was to assess the most probable number-polymerase chain reaction (MPNPCR) technique for detection of Listeria monocytogenes in salad vegetables in comparison with reference EN ISO 11290-2 and Food Drug Administration Bacteriological Analytical Manual method using artificial and naturally contaminated samples. Based on recovery of L. monocytogenes from artificially contaminated samples, MPN-PCR showed a moderate correlation (R=0.67) between spiking concentration and microbial levels which was better than the FDA-BAM method (R=0.642) and ISO 11290-2:1998 method (R=0.655). With naturally contaminated samples, it was found that L. monocytogenes was detected in 25% of the vegetable samples using MPN-PCR; 15% of the samples by the FDA-BAM method and 8% of samples using ISO 11290-2:1998 method. Overall, MPN-PCR was found to be a rapid and reliable method that could facilitate the enumeration of L. monocytogenes in vegetables.
The main objective of the present study was to investigate the effects of the frying media and storage time on the fatty acid composition (FAC) and iodine value (IV) of deep-fat fried potato chips. The frying experiment was conducted at 180ºC for five consecutive days. Six frying media were considered as the main treatments: refined, bleached, deodorized (RBD) palm olein (A), canola oil (C), RBD palm olein/sesame oil (AB, 1:1 w/w), RBD palm olein/canola oil (AC, 1:1, w/w), sesame oil/canola oil (BC, 1:1, w/w), and RBD palm olein/sesame oil/canola oil (ABC, 1:1:1, w/w/w). The initial degrees of unsaturation of the consumed oils, A, C, AB, AC, BC, and ABC, were 58.6, 94.0, 68.0, 72.2, 87.7, and 75.8 (g/100 g), respectively. The fatty acid analysis showed that there was a decrease in both the linolenic acid (C18:3) and linoleic acid (C18:2) contents, whereas the palmitic acid (C16:0) increased with a prolonged frying time. The chemical analysis showed that there was a significant (p < 0.05) difference in terms of the IV for each frying oil during the five consecutive days of frying (day 0 to 5). Oil C had the least stability in terms of deep-fat frying due to a high level of unsaturated fatty acids. Conversely, oil AC had the best stability due to the smallest reduction of the C18:2/C16:0 ratio and the IV.
This study investigates the effect of flaxseed oil towards physicochemical and sensory properties of reduced fat ice creams and its stability in ice-creams upon storage. Three formulations, (F1, F2, F3) were developed by substituting milk fat with flaxseed oil at levels of 2.5%, 5.0% and 7.5%, (w/w) respectively. Samples were subjected to sensory evaluation and analyses such as meltdown, titratable acidity, pH, total solids, protein and fatty acids composition. Incorporation of flaxseed oil into ice-cream showed no effects on physicochemical properties of the ice-creams. However, it increased the colour of ice-cream towards yellowness, decreased the sweetness, smoothness and creaminess. Flaxseed oil incorporation also slightly (P < 0.05) decreased the acceptance level of aroma, flavour, texture and overall acceptability of formulated icecreams. The most acceptable level of flaxseed oil substitution is at 2.5 %. Gas chromatography analysis showed that fatty acids slightly decreased upon storage.
This study was conducted to determine radical scavenging activity and vitamin antioxidant composition in red pitaya from organic plantation. For antioxidant vitamins analysis, a reverse-phase high performance liquid chromatography was used and radical scavenging activity of methanolic and water extract were determined using 1,1-diphenyl-2-pircrylhydrazyl assay. Results for radical scavenging activity, red pitaya methanolic extract achieved the highest percentage 70.13% compared with water extract (47.13%). Antioxidant vitamins composition in red pitaya showed that the concentration of vitamin A is 120.13 ± 0.69 μg/100 g freeze-dried sample, vitamin C is 540.27 ± 0.59 μg/100 g fresh samples and vitamin E is 105.67 ± 0.56 μg/100 g freeze-dried samples. This shows that red pitaya may become an alternative and potential source of natural antioxidant.
This study was performed to enumerate the total viable cell count of probiotic in five brands (A to E) of commercially cultured milk drinks that are available in the Malaysian market as well as to test their tolerance to various pH and bile concentrations by simulating the human gastrointestinal pH and bile concentration. The acid tolerance test was studied under pH 1.5 and 3.0 with 7.2 as control. The cell count for the acid tolerance test was obtained at an interval of 0, 1.5 and 3 hours respectively and was plated onto duplicate MRS agars to be incubated at 37°C for 48 hours. All cells recovered after 3 hours of pH treatment were selected for bile tolerance test in MRS broth containing bile concentrations of 0% (control), 0.3% and 2.0% and cell counts were recorded after 24 hours of incubation. The probiotic strains in products A, B, C & D met the suggested initial count of 106 CFU/ml with brand C recording the highest at 9.19 ± 0.14 log CFU/ml. Strains in product A, B & C showed good tolerance to pH 3.0 and 7.2 recording a count of >106 CFU/ml after 3 hours with a range of 6.60 – 9.04 log CFU/ml. The higher bile concentrations resulted in lower growth of strains in all the brands. Upon pH 1.5 treatment, only brand C recorded growth in all bile concentrations. After pH 3.0 treatment, all brands except brand E met the requirement of survival at 0.3% bile concentration. Results showed probiotics in product A, B & C met the initial count requirement, and exhibited good acid and bile tolerance therefore being a potentially good source of probiotic.
A total of 49 isolates of V. parahaemolyticus and 8 isolates of V. cholerae isolated from freshwater fish of patin (Pangasius hypopthalmus) and red tilapia (Oreochromis sp.) were purchased from different retail level in Selangor, Malaysia. All of the isolates showed a multiple resistances towards all 15 antibiotics tested. Some of the isolates show a high resistance to different antibiotics including bacitracin, vancomycin, tetracycline, furazididone, cephalothin and erythromycin. However, both species was susceptible towards imipenem. Overall antibiotics resistance patterns of all isolates were resistant from 2 to 14 resistance patterns with multiple antibiotic resistance (MAR) index ranging from 0.13 to 0.93 respectively. As the results obtained in the dendrogram produced from both species had indicates that these antibiotics were intensively used whether in the aquaculture farm through feeds during culture or at the hatchery production of seed. Thus, this study will provides an essential information of the MAR index and also the clustering analysis in order to determine the biosafety of Vibrio spp. in freshwater aquaculture fish sold at different retail level in Malaysia.
Malaysia, Biosafety Bill 2006 was approved by Parliament in July 2007, and labeling legislation will be implemented soon. In this study, duplex polymerase chain reaction (PCR) was carried out to detect
endogenous soybean lectin gene and exogenous cp4-epsps (5’-enolpyruvylshikimate-3-phospate synthase) gene simultaneously. Additionally, real-time PCR utilizing SYBR Green fluorescence dye were established for the quantitative analysis of Roundup Ready soybean (RRS), which is based on the two established calibration curve from cloned fragment of cp4-epsps gene and lectin gene respectively. Approximately, 39.5% (45/114) of the samples examined in this study contain RRS, animal feeds (31), processed food (13) and raw soybean (1). Additionally, 75.6% (34/45) of the positive samples were found contained RRS above 0.9%. The sensitive GMO quantitative approach described in this study enable the analysis of various samples and this will facilitate the labeling process.
This study reports on the microbiological quality of fresh and laboratory prepared pitaya fruit juice compared this with those collected from street vendors in the Penang island of Malaysia. Additionally, the microbial growth patterns were monitored during extended storage for up to 7 days at 2 different temperature ranges (at 10°C and 25±1°C). Results revealed the presence and increase in the incidence of bacteria, yeasts and moulds in all the juice samples (fresh and stored). Except for Klebsiella pneumoniae all the other foodborne pathogens screened in this study such as: Staphylococcus aureus, Salmonella sp. and generic Escherichia coli were absent. Our results highlights and stresses the need to employ proper hygienic conditions during harvesting and processing stages of pitaya fruit or their juices to improve the overall microbial quality to ensure adequate safety for consumers.
Protein efficiency ratio (PER) and protein digestibility are important parameters used in protein quality determination. Protein nutritive values of selected protein sources: buffalo meat, casein, soy protein isolate, and tempeh, with sodium caseinate as a reference formulation, were evaluated. Determination of proximate analysis, protein quality and protein digestibility were monitored. Procedures for evaluation of protein quality and digestibility included PER using the rat bioassay and in vivo Apparent Protein Digestibility (APD). The rats fed with buffalo meat had the highest mean increase in body weight (102.73g±8.95) while rats fed with tempeh had the lowest mean for increase in body weight (16.34g±9.11). Although the mean for body weight gained showed significant differences between all treatments (P0.05) found between casein and soy protein isolate for total food intake. For the PER value, buffalo meat had the highest value (2.99), followed by sodium caseinate (2.41), casein (1.93), soy protein isolate (1.52) and tempeh (1.10). The PER value for buffalo meat (2.99) was higher than sodium caseinate (2.41) while the rest of the treatment were comparatively lower than sodium caseinate. For the in vivo apparent protein digestibility, tempeh had the highest value (91.41%±3.76), followed by casein (91.34%±3.15), buffalo meat (90.79%±1.44), soy protein isolate (89.52%±2.96) and sodium caseinate (89.47%±2.31).
The antioxidant properties of skin, flesh and kernel of Canarium odontophyllum fruit were determined. The methanolic extracts of the fruit were screened for their total phenolic content and antioxidant properties. The averaged antioxidant properties (mM TE/g FM) in skin, flesh, and kernel of Canarium odontophyllum were 16.46 ± 0.24, 20.54 ± 0.35, and 8.89 ± 0.29, respectively by DPPH assay; 151.24 ± 9.75, 70.58 ± 2.98, and 5.65 ± 0.02, respectively by FRAP assay; and 47.9 ± 0.00, 11.61 ± 1.14, and 3.00 ± 0.00, respectively by β-Carotene bleaching method. The averaged OH scavenging activity (mg DMSOE/mg FM) in skin, flesh, and kernel of Canarium odontophyllum were 43.33 ± 13.85, 7.81 ± 1.42, and 3.31 ± 0.80, respectively. While averaged total phenolic content (mg GAE/100g FM) were 387.5 ± 33.23, 267.0 ± 4.24, and 51.0 ± 0.00 for skin, flesh, and kernel respectively. Antioxidant activities were positively correlated with the total phenolic content (0.71 ≤ r ≤ 0.84).
This study was conducted to evaluate antimicrobial properties of ethanolic extracts of the leaves of Nephelium lappaceum, Curcuma longa, Cinnamomun cassia, Durio zibethinus, Vitex trifolia, Amaranthus tricolor, Syzygium samarangense and Manihot esculenta. Antibacterial properties of the extracts were studied against fifteen strains of different gram positive and gram negative pathogenic bacteria, including Bacillus cereus, Listeria monocytogenes, Staphylococcus aureus, Vibrio para, and Escherichia coli using the agar disk diffusion method. Among the tested extracts, only Amaranthus tricolor exhibited specific inhibition of one of the tested bacteria; Bacillus cereus. Using the microdilution method, its minimum inhibitory concentration (MIC) value was determined to be 20 mg/mL.
Rubber seed as a waste product from rubber plantations contains nutritive values that can be harnessed
as food for human, feed for animals or biofuel for energy. Proximate analysis showed moisture content of
3.99%, protein content of 17.41 g/100g, fat content of 68.53 ± 0.04 g/100g and ash content of 3.08 ± 0.01
g/100g. Amino acid in rubber seed is high in Glutamic acid (16.13%) and low in Cysteine (0.78%). Despite its potential as a source of protein, fresh rubber seeds contain a toxic factor, cyanogenetic glucoside (186 mg/kg). FAME analysis indicated that rubber seed oil is high in oleic, linoleic and linolenic acid. The fuel potential of rubber seed (585.41 kJ/kg) is in reasonable agreement with ASTM.
The study investigated socio-demographic factors and product attributes affecting purchase decision of special rice by Malaysian consumer. The primary data were analyzed by using binary logit model.
Demographic factors and consumer preference for special rice (with reference to basmati rice) attributes were identified to affect purchasing behavior for special rice. Size of household, marital status, number of children, household income and gender of consumers are the main socio-demographic factors that significantly influence households’ choices of special rice for home consumption in the Klang Valley area. The findings also suggest that product attributes such as flavor and aroma, availability, brand name and quality also influence the frequent purchasing of Basmati rice among the Malaysian consumers. However price and easy preparation are not significant in influencing the frequent purchasing of Basmati rice since most consumers are aware that special rice such as Basmati is expensive and all rice has to be prepared in a usual way.
Efficacy of some Malaysian herbal aqueous extracts, BHA/BHT (synthetic antioxidants) and ascorbic acid in retarding oxidative rancidity was tested with cakes. The development of lipid oxidation products during 15 days at room temperature was evaluated by means of Peroxide Value (PV) and Thiobarbituric acidreactive substances (TBARS) value. The six formulations consists of control sample (cake without addition of antioxidant) (F1), cake added with curry leaves extract (F2), cake incorporated with kesum leaves extract (F3), cake added with tenggek burung leaves extract (F4), cake incorporated with ascorbic acid (F5) and cake added with BHA/BHT (F6). Formulation with the incorporation of tenggek burung leaves extract showed powerful oxidative stability effect compared to the formulations with othe plant extracts and control sample. However, cakes with BHA/BHT showed the strongest oxidative stability throughout the storage period. Therefore, it is suggested that tenggek burung leaves extract can be added into the food system for effectiveness as antioxidant to prolong the shelf life of the product.
Pineapple (Ananas comosus), Bromeliaceae family, is a fruit grows in tropical countries including Malaysia. This fruit has several pharmacological benefits due to the presence of high concentration of bromelain (cysteine proteases). Condition of elevated temperature will induce deformation of enzyme and result in loss of activity. Sulfhydryl groups in cysteine proteases are readily to be oxidized and might account for the denaturation of bromelain at elevated temperature. Polyphenol from ethanolic cashew leave extract could be complexed with bromelain to stabilize the enzymatic activity. In thermal stability test, the heat damage effect on bromelain was ten times reduced after complexing with cashew extract. The enzymatic activity of free bromelain decreased gradually from 25 o C to 95 o C. Complexed bromelain was stable in activity to heating up to 85 o C. Bromelainpolyphenol complex showed a good heat resistance. The result revealed that polyphenol could protect bromelain in pineapple juice from heat denaturation.
The fatty acid composition and trans fatty acid (TFA) contents of biscuits products were determined by gas chromatography, using a highly polar 100m capillary column (HP-88) and flame ionization detection. Total TFA ranged from 0.00 – 0.52 g/100 g total fatty acids and 0.12 – 0.68 g/100 g total fatty acids for local packed and unpacked biscuits, respectively. In imported biscuits, total TFA was higher ranging from 0.03 – 3.09 g/100 g of total fatty acids. Trans 16:1 was the most abundant, with values ranging from 0.01% to 38% followed by trans 18:1 Δ11 (0.01% - 13.11%), trans 18:1 Δ9 (0.01% - 4.68%), trans 18:2 (0.23% - 2.77%) and small quantities of trans 18:1 Δ6. CLA, the natural TFA constituted from 0.1% to
This research was carried out to determine the fructooligosaccharides content in local honey samples, namely the wild Malaysian Tualang honey and common wild honey obtained from Tapah, Perak and a commercial Tualang honey. Local wild honeys were found to contain a higher concentration of fructooligosaccharides (FOS) compared to the commercial Tualang honey. The FOS quantified from local wild honeys was inulobiose, kestose and nystose. Nystoses were found at a very low amount in the commercial Tualang honey. The effects of honey on the growth of Bifidobacterium longum BB 536 were investigated. Both wild and commercial honey samples including FOS standard were found to support the growth of B. longum. The pH value of the skim milk + honey inoculated with the probiotic strain decreases as expected. Addition of honey was found to support the growth of B. longum BB 536.