Cantaloupes continue to ripen after harvesting which is caused by ethylene production due to climacteric behaviour during postharvest storage. In this study, the cantaloupe fruits harvested at commercial maturity were evaluated for quality attributes during three weeks of storage at 10°C and a relative humidity (RH) of 90±5%. In addition, fresh-cut samples were stored for a further 19 days at 2°C and 87% RH. The fresh-cut samples were prepared on a weekly basis by dipping into deionised water (control) at 2°C for 1 minute. The effect of postharvest storage of cantaloupe on the physico-chemical properties and microbial activity was observed prior to fresh-cut processing. It was found that firmness, luminosity (L*), and titratable acidity (TA) decreased, while total soluble solids (TSS), pH, TSS:TA ratio, microbial activity (total plate count (TPC) and yeast and mould (YM)) of the fresh-cut increased over the postharvest storage period of the fruit. Meanwhile, the orange colour and the intensity (hue angle, hab, and chromaticity) of the flesh did not differ significantly during storage. The cantaloupe stored for three weeks at a low temperature indicated a successful potential for fresh-cut processing due to good maintenance of the product quality.
Response surface methodology (RSM) was used to optimize the concentrations of chitosan and glycerol for coating Berangan banana (Musa sapientum cv. Berangan). The effects of main edible coating components, chitosan (0.5-2.5%, w/w) and glycerol (0-2%, w/w) on weight loss, firmness, total colour difference, total soluble solids content (TSS) and titratable acidity (TA) of coated banana were studied during 10 days of storage at 26±2°C and 40-50% relative humidity. Results showed that the experimental data could be adequately fitted into a second-order polynomial model with coefficient of determination (R 2 ) ranging from 0.745 to 0.930 for all the variables studied. In general, the chitosan concentration appeared to be the most significant (P< 0.1) factor influencing all variables except for TSS. The optimum concentration of chitosan and glycerol were predicted to be 2.02% and 0.18%, respectively. Statistical assessment showed insignificant difference between experimental and predicted values.
This study was conducted to investigate the sensitivity and detection of porcine DNA in raw materials, ingredients and finished bakery products by polymerase chain reaction (PCR) - southern hybridization on chip analysis. A total of 20 samples (n=20* 3) with three replicates for each samples were obtained from a bakery factory located in Bangi, Selangor from January to December 2012. The sensitivity level of PCR-southern hybridization on chip was 0.001 ng. The species-specific oligonucleotide primers used in PCR-southern hybridization were targeted on the mitochondria DNA (mtDNA) of cytochrome b (cyt b) gene sequence, namely cty b biotin-labeled oligonucleotide primers. The amplicon from PCR amplification was 276 bp in size. None of the raw materials, ingredients and finished bakery product samples was positive towards porcine DNA, except for the positive control. The results in the present study demonstrated that the PCR- southern-hybridization technique on the gene chip (OliproTM Porcine gene chip) is a sensitive tool for monitoring the porcine component in highly processed ingredients and finished bakery products.
The evaluation of a dryer performance in terms of energy consumption, drying capacity and
quality of final product is the main concern of rice milling industry at any time. A study was
implemented to investigate on the benefits of common drying practices by studying the drying
performances of flat-bed and inclined-bed dryers which are popular in rice industry in Malaysia
and neighbouring countries. For this purpose, flat-bed dryer (FBD) and inclined-bed dryer
(IBD) were designed, fabricated and operated in the laboratory based on actual industrial
drying conditions. The results revealed that inclined-bed drying significantly increased drying
capacity (ton m-2 h-1) of up to 25 % at drying temperature of 42-43°C and almost 29 % at 38-
39°C drying air temperature compared to flat-bed drying. Furthermore, overall drying energy
consumption in IBD was found to vary between 78.6 to 91.97 kW.h ton-1, while for FBD the
energy consumption was more than 200 kW.h ton-1 for both levels of drying air temperatures.
Both dryers were found to produce rice with desired/ acceptable commercial quality index,
even though the head rice yields of FBD were higher than that of IBDs.
A study was carried out to compare the composition and thermal profiles of the fat component of six brands of commercial biscuits (BA, BB, BC, BD, BE & BF) with those of lard and palm oil. Extraction of fat from biscuit samples was done using petroleum ether according to the soxhlet extraction procedure. The isolated fat samples along with lard and palm oil were analyzed using gas liquid chromatography (GLC), reversed-phase high performance liquid chromatography (RP-HPLC), and differential scanning calorimetry (DSC). According to GLC analysis, palm oil, lard and all six biscuit brands had either palmitic or oleic acid as major fatty acids. Sn-2 positional analysis of fatty acids showed that oleic (> 60%) as the most dominant fatty acid of palm oil and biscuit brands BA, BB, BC, and BD while palmitic (> 60%) as the most dominant fatty acid of lard and biscuit brands BE and BF. RP-HPLC analysis showed that the triacylglycerol (TAG) profiles of lard and biscuit brands BE and BF were closely similar while those of brands BA, BB, BC, and BD and palm oil were similar. DSC analysis showed that the cooling and heating profiles of lard and brands BE and BF were similar, while those of palm oil and brands BA, BB, BC, and BD were similar. Hence, this study concluded that biscuit brands BE and BF are not suitable for consumers whose religious restriction prohibit the use of lard as food ingredient.
The native sago starch exists as a compact crystalline structure and is not efficiently hydrolyzed by Raw Starch Degrading Enzyme (RSDE). In order to enhance its hydrolysability, the starch was treated with acid and heated below its gelatinization temperature, thus increasing the accessibility of the sago starch granule to enzymatic attack. Results showed that treatment of sago starch with acid at pH 2.0 and temperature 65oC for 2 hours greatly enhanced its conversion rate to glucose from 53.3% to 71.9%. It is clearly shown that high yield of glucose is produced during hydrolysis of acid-treated sago starch using the Raw Starch Degrading Enzyme from Acremonium sp. The difference between the acid-treated and untreated sago starch in this study could be due to the differences on the surface of the sago starch granule which may influence the accessibility and diffusion of enzyme into the starch during hydrolysis.
Clinacanthus nutans is the native medicinal herbs that grow in tropical climate, mainly can be found in Malaysia and Thailand. Clinacanthus nutans is used to boost immunity and for detoxification. It is claiming to promote bowel movement and other health promotions, such as skin care, diuresis and cancer (such as lung, ovary, uterine, prostate, nasopharyngeal and breast). This study focused on the effects of solvents towards antioxidant and antimicrobial properties of C. nutans (Belalai Gajah/ Sabah Snake Grass) leaves and stems. Freeze-dried leaves and stems were homogenized before testing its antimicrobial properties. The 70% acetone (Merck, Germany) was prepared by dissolving fine powder of C. nutans in 1:10 solvent ratio with 70% acetone using ultrasonic extraction for 1 h in an ultrasonic bath (Soniclean, Thebarton, Australia). Ten bacteria (Bacillus cereus, B. subtilis, Escherichia coli, Klebsiella pneumonia, Listeria monocytogenes, Pseudomonas aureginosa, Salmonella typhimurium, Shigella boydii, Staphylococcus aureus and S. epidemidis) and four fungi (Aspergillus niger, Candida albicans, Rhizopus stolonifer and Saccharomyces cerevisiae) were used in the antimicrobial study employing minimum inhibitory concentration (MIC) and minimal microcidal concentration (MMC) methods. The data obtained were statistically analysed using SPSS Inc. Version 22 (Chicago, USA). The MIC values of acetone extracts for the selected bacteria and fungi ranged between 6.25 – 100.00 mg/ mL while the MMC values of acetone extracts for the selected bacteria and fungi were between 25.00 - >100.00 mg/ mL. Recommendation on phytochemicals investigation should be conducted to determine the potential of compounds toward antioxidant and antimicrobial properties.
Acacia polyacantha gum (APG) is a dried exudate which obtained from the stems and branches of Acacia polyacantha trees. APG is rich in soluble dietary fibers as well as organic compounds. In this study quantitation of the levels of total phenolics content (TPC) and antioxidant activities were conducted using ABTS and CUPRAC assays for APG extraction using pure solvents (methanol, ethanol, acetone) and their aqueous mixtures at 50% and 100%. The antioxidant levels were evaluated by 2,2’-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS+) radical cation deculturization and cupric iron reducing capacity in the presence of neocuproine (CUPRAC) for the evaluation of reducing power, and (TPC) was evaluated by the Folin-Ciocalteu method. The solvent Methanol (50%) gave the best extraction ratio for APG presented by highest (TPC 60.78 mg GAE/100g of DW, CUPRAC 34.65 mg TE/100g DW, and, ABTS about 37.65 mg TE/100g DW respectively), followed by ethanol 50% extract. On the other hand, pure methanol showed the lowest TPC 5.33 mg GAE/100g of DW, ABTS 10.9 mg TE/100g DW, and CUPRAC 7.80 mg TE/100g DW, values respectively. Therefore, the variation in the antioxidant capacity of extracts was possibly due to the difference of polarity, immiscibility and the nature of the APG compounds extracted using various solvents. The higher content of antioxidant activity in APG shall be useful to human health if it is properly utilized.
This work presents the characterization of selected bioactive compounds of local herbs
through their photonic spectrum. A Shimadzu spectrophotometer was used to map bioactive
compounds extracted from Andrographis paniculata, Ficus deltoidea, Orthosiphon stamineus
and Centella asiatica. Dominant peaks and repeatability were the determinant parameters
in this study. Absorbance peaks of bioactive compounds were calibrated against respective
standardized chemicals obtained from reputable suppliers. The results obtained indicated
that absorbance peaks from different bioactive compounds could be identified by photonic
spectrum. Most bioactive markers were detected within the wavelength range of 200 nm to 350
nm, using a Deuterium (190 nm to 450 nm) light source and corresponding refraction grating.
A mathematical relationship of concentration versus absorbance at different wavelengths for
selected bioactive compounds were identified. The significance of the photonic characterization
of these phytochemicals forms the basis for a mathematical model in a decision support system
of a proposed mobile sensor prototype development.
Breast cancer is considered as one of the most common cancers all over the world. A huge effort has been made to create a safe and cost effective breast cancer treatment. All of these features exist in the plants sources. In this study, the effect of local vegetable salad, Premna serratifolia (Bebuas) against MCF-7 cells (human breast adenocarcinoma) was determined. The optimum condition to extract breast cancer cytotoxic compound from the plant was investigated and the exact cytotoxic compound was identified as well. To determine the plant cytotoxicity effect against MCF-7 cells, MTT assay was used. Two important parameters in the sonication extraction method which are duration of time and temperature were optimized by carrying out a series of experiments which were designed by Face Centered Central Composite Design (FCCCD). The extraction efficiency of each experiment was determined by measuring the yield of extract and the half maximal inhibitory concentration (IC50) of the extract against MCF-7 cells. The results obtained from the experiments were fitted to the second order polynomial model to generate equation that was used to determine best extraction processing condition. Based on the generated equation, the best sonication processing condition to extract the cytotoxic compound is at 30oC for 67 min. Analysis of variance (ANOVA) showed that the duration of extraction time has great influence (p
Mushrooms have been consumed by mankind for millennia. In Malaysia, there are many species of edible mushrooms which are either cultivated (Agaricus spp., Auricularia spp., Pleurotus spp.) or harvested in the wild (Ganoderma spp., Polyporus spp., Termitomyces spp.). With the advancement of technology, numerous discoveries have been made that elucidated the nutritional (high in fibres, proteins, vitamins; low in fats, cholesterols, sodium) and medicinal (anti-oxidative, anti-hypertensive, neuritogenesis) properties of edible mushrooms, all of which are highly beneficial for the maintenance of human health and well-being. This review thus compiles and documents the available literatures on edible mushrooms reported from Malaysia complete with scientific, English, and vernacular names for future references; provides a comprehensive and updated overview on the nutritional and medicinal properties edible mushrooms reported from Malaysia; and identifies the research gaps to promote further research and development on edible mushrooms reported from Malaysia. Overall, Malaysia is and remains a natural repository for wild and cultivated edible mushrooms. Deeper investigation on their nutritional and medicinal properties will certainly serve as an impetus for economic as well as scientific progress.
Fish protein hydrolysate was recovered from tilapia by-product (TB) through enzymatic hydrolysis using alcalase enzyme. Hydrolysis reaction of TB was monitored according to the degree of hydrolysis (DH) by employing O-phtaldialdehyde (OPA) method. Optimization process for obtaining high yield of TB protein hydrolysate was performed using response surface methodology (RSM) by optimizing a combination of four independent variables namely, pH (6.5-8.5), temperature (55-70oC), substrate concentration (10-17.5% w/v), and enzyme concentration (1.5-3.5% w/w) with (DH) as a response. The optimum enzymatic hydrolysis conditions were obtained at pH 7.5, temperature of 60oC, substrate concentration of 15% (w/v) and 2.5% (w/w) of enzyme concentration and yielded about 20.20% of DH after hydrolyzing for 120 min. RSM generated model predicted that 20.42% of DH could be achieved at these conditions and this model was valid based on the DH value obtained from the experimental study (20.31%) which was quite similar with the predicted value. High yield of DH obtained from the optimization process could produce fish protein hydrolysate with good nutritional and functional properties.
Volvariella volvacea (Family: Plutaceae), also more commonly known as paddy straw mushroom, is an edible mushroom with high nutritional content. It is usually cultivated using lignocellulosic-based materials for enhanced production. However, V. volvacea is highly perishable and easily deteriorates in terms of quality and appearance after harvest. The present paper thus aimed to provide a critical review on aspects related to the production of V. volvacea using palm oil empty fruit bunch as cultivation substrate. The different stages of V. volvacea development are also highlighted. The present review also provides some information on the preservation techniques and appropriate postharvest management in extending V. volvacea shelf life to further boost the paddy straw mushroom industry
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).
Microbiological quality analysis of freshwater prawns from three sampling sites in Peninsular Malaysia viz: Site 1- Kg. Jumbang, Negri Sembilan; Site 2- Kg. Cangkat Tin, Perak and Site 3- Kg. Cenderiang, Perak for total mesophilic and psychrophilic aerobic counts, proteolytic bacterial counts, histamine producing bacteria, cadaverine producing bacteria and putrescine producing bacteria in the prawns and pond water for the three sites showed that the microbiological quality of freshwater prawns is related to the microflora of pond water in which they were grown. The initial bacterial counts indicated the values were in the range of log 4+ CFU/g for all samples. Total mesophilic and psychrophilic counts of the head regions were higher than that of the body regions for all prawn samples and types of growth media tested. All samples showed an increase in counts with time and temperature of storage up to log 7+ CFU/g for mesophilic counts after 12 hours at ambient, 6 days at 10 ± 2°C and 12 days at iced storage. The samples from Site 2 had relatively higher counts compared to the other two sites which correlated well with the levels determined in the pond water. Similar trends were observed for psychrophilic counts but at lower values for the different types of media studied.
Effects of preservatives on quality changes and shelf life of shrimp during iced storage indicated that boric acid, lactic acid and sodium metabisulphite managed to inhibit psychrophilic bacteria and biogenic amines formation in prawns while maintaining the mesophilic counts at lower levels during iced storage.
This study was carried out to determine the proximate, functional and pasting properties of breadfruit starch. Breadfruit starch was isolated from matured breadfruit (Artocarpus altilis) and was analyzed for its fuctional, proximate and pasting properties. The starch contains 10.83%, 0.53%, 0.39%, 22.52%, 77.48% and 1.77% moisture, crude protein, fat, amylose, amylopectin and ash contents respectively. The average particle size, pH, bulk density and dispersibility of the breadfruit starch were 18 μm, 6.5, 0.673 g/mls, and 40.67% respectively. The swelling power of the breadfruit starch increases with increase in temperature, but there was a rapid increase in the swelling power from 70 to 80 0C. The pasting temperature of the starch paste was 84.05 0C, setback and breakdown values were 40.08 and 7.92 RVU respectively. The peak viscosity value was 121.25 RVU while final viscosity value was 153.42 RVU. This study concluded that breadfruit starch has an array of functional, pasting and proximate properties that can facilitate its use in so many areas where the properties of other starches are acceptable.
Furan has been classified as a possible carcinogen and substantiated evidences have also shown
that conventional thermal treatment could stimulate furan development in food products.
Ultraviolet light (UVC) is currently known as an alternative method widely used in pasteurizing
juice. However, the effect of UVC in inducing furan development has not been studied
specifically on UVC-treated pummelo juice. Thus, the aim of this study was to investigate the
development of furan in UVC-treated pummelo juice and its relationships to the juice sugar
contents. Our results showed that furan development within the juice post-UVC treatment was
dose-dependent and inversely proportional to the amount of sugar and ascorbic acid (p
Aflatoxins are carcinogenic, mutagenic and teratogenic fungal toxins predominantly produced by Aspergillus flavus (A. flavus) and Aspergillus parasiticus (A. parasiticus). Members of the Aspergillus family are wound-invading pathogens that can infect pistachio trees and nuts. The pistachio nut is a favorite tree nut worldwide, and more than half of the world’s pistachio production is from Iran. Pistachio nuts can easily be infected with Aspergillus spp. due to early splitting or due to animal, insect or physical damage. Any established infection of Aspergillus under high relative humidity and temperature results in the production and rapid accumulation of aflatoxins in pistachio nuts. It is impractical to remove aflatoxins from pistachio nuts after they are produced. Some microorganisms (such as saprophytic yeasts) have been reported to have an antagonistic effect against Aspergillus spp. This study aimed to isolate saprophytic yeasts from pistachio fruits and leaves and investigate their biocontrol activities against a toxigenic strain of Aspergillus flavus (A. flavus). Saprophytic yeasts were identified based on their morphological properties and biochemical tests. In total, 24 yeast isolates were obtained from pistachio fruits and leaves, and their antagonistic effect on A. flavus (PTCC 5006) was investigated. Five saprophytic yeast isolates, displaying the highest biocontrol activities against A. flavus (PTCC 5006), were identified as Pseudozyma fusiformata, Cryptococcus albidus, Rhodotorula fragaria, Cryptococcus hungaricus and Rhodotorula hinula. The biocontrol activities of these yeast isolates were evaluated by their inhibitory effects on sporulation, colony expansion, biomass production and prevention of aflatoxin B1 (AFB1) production. Pseudozyma fusiformata was the most effective yeast isolate in terms of spore reduction (84.6%) and inhibition of AFB1 production (89.1%). Cryptococcus albidus produced the maximum reduction in fungal dry weight (77.9%). Based on these results, isolated saprophytic yeasts from pistachio fruits and leaves can be used as effective biocontrol agents against the growth of Aspergillus and aflatoxin production.
Forty three (n=43) genomic DNA of Escherichia coli (11 isolates from eggs and 32 isolates from imported beef meats) were characterized by shiga toxin 1 (stx1), enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) and random amplified polymorphic DNA-PCR (RAPD-PCR) analyses. In the shiga toxin 1 (stx1) gene detection with primer stx 1F (5’-TTCTTCGGTATCCTATTCCC-3’) and stx 1R (5’- CTGTCACAGTAACAACCGT-3’), 9 E. coli of beef meats isolates were positive toward sxt1 gene. The results of the ERIC-PCR and RAPD-PCR were analyzed using GelCompar II software. ERIC-PCR with primer ERIC1 (5’-CACTTAGGGGTCCTCGAATGTA -3’) and ERIC2 (5’-AAGTAAGTGACTGGGGTGAGCG-3’) discriminated the E. coli into 6 clusters and 10 single isolates at 80% similarity. RAPD-PCR with primer Gen8 and Gen9, produced 10 clusters and 15 single isolates and 12 clusters and 14 single isolates of 80%, respectively. These results demonstrated that both ERIC-PCR and RAPD-PCR are useful and suitable tools for molecular typing of those isolates examined.
Food irradiation is a process carried out in order to improve hygienic quality and germination
control, retarding sprouting, also enhancing physical attributes of the food product. In order to
provide for food safety, radiation dosimetry in irradiated foods is required. In present studies
use is made of germanium doped (Ge-doped) optical fibres of various form and dimensions.
The fibres are irradiated using a gamma source irradiator (Gamma Cell 220 Excel), with doses
from 1 kGy up to 10 kGy. For the particular Ge-doped optical fibres, investigation has been
made of linearity with dose, reproducibility, and fading, intercomparisons being made. The
fibres all exhibit TL yields that are linear with dose from 1 kGy up to 10 kGy, exceeding the
dose range of all commercial high dose dosimeters used in the food irradiation industry. In
respect of the flat fibre dosimeters, the mean reproducibility was found to be within 0.53%
to 4.96%, also offering low signal loss (fading), within 13.41% (for fibres of cross-sectional
dimensions 60 x 180 µm) to 20.12% (for fibres of cross-sectional dimensions 200 x 750µm),
after 22 days of storage.