The use of component from Ganoderma lucidum as prebiotic source is interesting as the G. lucidum itself was known for more than a decade in the traditional Chinese medicine. In this work, Ganoderma lucidum crude polysaccharides (GLCP) and Polysaccharide-fraction number 2 (PF-2) were used as carbon sources in the fermentation with Bifidobacterium sp. The results showed the potential of prebiotic effect of the G. lucidum extract in batch-culture fermentation based on increment in the growth of bacteria used (0.4 – 1.5 log10 CFU/mL) after 18h fermentation. Fermentation was further done using faecal materials as bacterial inocula and bacterial growth changes were examined using real-time PCR. The results showed the ability of GLCP and PF-2 to support the growth of Bifidobacterium genus with 0.3 and 0.7 log10 cells/ml increased, respectively. Interestingly, Lactobacillus which is known as beneficial bacterial genus also showed growth increment with 0.7 and 1 log10 cells/ml increased. The competition for carbon sources thus inhibits the growth of potentially harmful genus, Salmonella (0.3 and 0.5 log10 cells/ml) in comparison to the control.
Plant tissues, especially durian tissues contain high content of polysaccharides, polyphenols and other secondary metabolites which can co-precipitate with RNA causing problem in further transcriptomic study. In this experiment, three basic chaotic agents, CTAB, SDS and guanidine are used in three basic protocols for RNA isolation. The effectiveness of each method was determined by spectrophotometer, denaturing agarose gels analysis and northern blot hybridization. CTAB combining with additional sodium acetate precipitation step showed highest yield and best quality of isolated RNA which was free from contaminations of polysaccharides, polyphenols and other secondary metabolites. Furthermore, the total RNA from 4-month old durian flesh of clone D24 was successfully used to construct a cDNA library. In conclusion, CTAB method is effective to isolate total RNA on various types of durian tissues for further gene expression analysis.
Gelatin is widely used in food and pharmaceutical products. However, the addition of gelatin especially in food products becomes a controversial issue among Muslims due to its animal origin. Thus, the present study was aimed to detect and differentiate the origin of gelatin added in processed foods using a combination method of sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) and Principal Component Analysis (PCA). Porcine gelatin had exhibited 11 prominent polypeptides compared to bovine gelatin with 2 prominent polypeptides. Polypeptides of both gelatin sources at molecular weight ranged from 53 to 220 kDa can be used to differentiate between porcine and bovine gelatins using PCA. The efficiency in extracting gelatin from processed foods by different solutions was also evaluated. Extraction of gelatin in processed foods by cold acetone and deionised water had exhibited a similar polypeptide patterns, suggesting both solutions are suitable. The study indicated that approach of a simple gelatin extraction combined with SDS-PAGE and PCA, may provide robust information for gelatin species differentiation of processed foods.
Thermal treatment is commonly applied in juice manufacturing as a method to pasteurize juices. However the heat may deteriorate some of the essential compounds in the juice, especially heat-sensitive antioxidants. Therefore non-thermal treatment such as ultraviolet (UV) ray has been proposed as an alternative for pasteurization. The objective of this study was to compare the effect of thermal and UV treatments on the content of antioxidants (phenolic acids, flavonoids, carotenoids, ascorbic acids) and antioxidant capacity of single strength pineapple juice. The antioxidants stability of juices throughout 14 days of refrigerated storage was also studied. Ultraviolet treatment shows higher ascorbic acid content after treatment as compared to thermally treated single strength pineapple juice. Storage time affected the studied antioxidants, where UV
treatment provided better stability to ascorbic acid content while thermal treatment provided better stability to flavonoids and carotenoids.
Preservative fruits have gained popularity in recent years as part of food consumption, but their benefits towards human health are not known. This study compared total phenolic (TPC), total flavonoid (TFC), β-carotene, lycopene, ascorbic acid (AA) contents and antioxidant properties between fresh and pickled papaya. The results indicated that mean TPC (mg gallic acid equivalent/100 g dry samples), TFC (mg rutin equivalent/100 g dry samples), β-carotene (µg/100 g edible portions), lycopene (µg/100 g edible portions) and AA content (mg/100 g edible portions) were higher in fresh papaya (141.66 ± 11.71; 57.80 ± 2.11; 793.83 ± 5.47; 779.69 ± 5.55; 70.37 ± 0.65) as compared to pickled form. Antioxidant activity (%) measured by DPPH and β-Carotene-Linoleate bleaching method was higher in fresh papaya (56.83 ± 4.68; 77.56 ± 1.40). Total phenolic, total flavonoid, ascorbic acid, beta carotene and lycopene were strongly correlated with antioxidant activity and scavenging activity (0.905 ≤ r ≤ 1.00) indicating that were important contributors to antioxidant properties in papaya extracts. The pickling process of papaya caused a significant decrease in their antioxidant component and activity
The influence of variety (Cavendish and Dream), stage of ripeness (green and ripe) and parts (pulp and peel) on antioxidative compounds and antioxidant activity of banana fruit was investigated. The TPC and TFC ranged widely from 75.01 to 685.57 mg GAE/100 g and 39.01 to 389.33 mg CEQ/100 g of dry matter respectively. Cavendish banana flour contained higher TPC and TFC compared to Dream variety. TPC and TFC values of banana peel were higher than those of banana pulp. Also, green banana showed higher TPC and TFC values than those of ripe fruit. Radical scavenging activities (inhibition of DPPH) of the extracts ranged from 26.55 to 52.66%. Although Dream banana peel extracts appeared to have low TPC and TFC, its antioxidant activities were ranked moderate to high. This implies that antioxidative compounds other than phenolics and flavonoids were probably responsible for inhibition of DPPH.
MeSH terms: Flavonoids; Flour; Fruit; Oxidation-Reduction; Phenols; Musa
The effects of different types of low-sweetness sugar (lactitol, maltodexrin, palatinit, polydextrose,
trehalose) on the physicochemical properties of threadfin bream (Nemipterus spp.) surimi during six months of frozen storage were investigated. The characteristics analyzed were moisture content, pH, water-holding capacity, whiteness, folding test, gel strength, expressible moisture, and texture profile analyses. Generally, the cryoprotective effectiveness decreased as the storage time increased. Polydextrose was able to maintain a water-holding capacity of 77.0%, 98.6% whiteness, a folding test value of 100%, and a gel strength of 53.6% compared with its initial value during six months of frozen storage. Meanwhile, sucrose was able to maintain a water-holding capacity of 80.3%, 98.6% whiteness, a folding test value of 75%, and a gel strength of 56.8%
compared with its initial value. Raw surimi was able to maintain water holding capacity of 62.2%, 98.7% whiteness, a folding test value of 75%, and a gel strength of 36.0% compared with its initial value. It is suggested that, polydextrose as a potential alternative cryoprotectant to replace other low-sweetness sugars.
The effect of storage time on the quality of ultraviolet-irradiated and thermally pasteurised pineapple juice was evaluated. The juices were irradiated with ultraviolet light (UV-C) at wavelength 254 nm (53.42 mJ/cm2, 4.918 s), thermally pasteurised at 800C for 10 minutes and stored at 40C for 13 weeks. There were significant changes in the total soluble solids, pH, titratable acidity and turbidity of UV-irradiated juice during storage, whereas for the same quality attributes of thermally pasteurised juice remained stable throughout the storage time. There were no significant changes in total phenolics for both treatments throughout the storage period. Other quality parameters (ascorbic acid, colour L, hue angle and chroma) were significantly affected by the storage time. Regarding the microbiological analysis, the total plate counts and yeast and mould counts of the UV-irradiated juice increased gradually throughout the 13 weeks of storage while these parameters remained unchanged in the thermally pasteurised juice with almost no microorganism growth. UV-irradiated pineapple juice preserved better quality attributes (TSS, pH, titratable acidity, ascorbic acid, turbidity, total phenolic, L (lightness), hue angle and chroma) than the thermal pasteurised juice during the storage time. Hence, UV irradiation has great potential as an alternative technology to thermal pasteurisation in producing products of high nutritive values.
Mushrooms are well known to be healthy because they are low in calories, fat and cholesterol level but rich in vitamin and other essential nutrients. The grey oyster mushroom, Pleurotus sajor-caju (PSC), is a common edible mushroom and is now grown commercially around the world for food and food products. The ability of PSC in changing physical characteristics and sensory properties of beef patty formulated with this fungus were investigated. Result shows beef patty added with 50% ground PSC recorded the highest concentration total dietary fibre (TDF) at 9.95 g/100g compared to beef patty containing 25% of PSC (7.00 g/100g) and control (3.90g/100g). Beef which was replaced with 25% of PSC, recorded the highest cooking yield (76.62%) and moisture retention (59.80%) respectively. On the other physical traits, beef patty containing 25%
PSC recorded fat retention at 89.04% and was not significant (P
This study was aimed to evaluate the effect of soursop (Annona muricata L.) extract on Sprague-Dawley rats subjected to in vivo 28-day repeated doses. The extract was given to the study group via force feeding. In the 28-day study, Annona muricata L. extract was dosed at 0 (CD, control dose), 0.5 (LD, low dose), 1.0 (MD, medium dose), 2.0g/kg (HD, high dose) body weight. For control group, distilled water was given to the animals. Administration of Annona muricata L. extract did not cause negative effect in blood hematology even though a statistically significant (p
MeSH terms: Animals; Body Weight; Enteral Nutrition; Hematology; Rats, Sprague-Dawley; Annona; Control Groups; Rats
Presence of Norovirus in food can cause viral gasteroenteritis. Recently, lots of reports relating to Norovirus in food have been published. Special attention must be paid to the raw foods as they are not subjected to further heat treatment. In this study, pegaga, kesum, tauge and ulam raja (popular salad vegetables in Malaysia) were investigated for Norovirus. A total of 32 samples from each type of salad vegetables were purchased from local market and analyzed using One-step RT-PCR (Reverse Transcriptase-Polymerase Chain Reaction) for both genogroups namely Norovirus Genogroup I and Genogroup II. Results showed that tauge had the highest contamination with Norovirus Genogroup I (15.6%) comparing to pegaga (9.4%), kesum (12.5%)
and ulam raja (0%). Samples were free from Norovirus Genogroup II. The study showed that raw vegetables are high-risk foods and can be contaminated with Norovirus.
MeSH terms: Animals; Attention; Genotype; Hot Temperature; Hyperthermia, Induced; Malaysia; RNA-Directed DNA Polymerase; Skates (Fish); Vegetables; Caliciviridae Infections; Reverse Transcriptase Polymerase Chain Reaction; Norovirus; Raw Foods
Quality attributes of steamed bread without green banana flour (BF) (CON), substituted with 30%
BF (BBFI) and 30% BF + 8% gluten (BBFII) were determined. The green banana flour (BF) and the mixture of wheat flour (WF) substituted with 30% BF + 8% gluten (FBFII) was significantly highest in water holding capacity and oil holding capacities, respectively. Potassium, calcium and magnesium were significantly higher in BBFI and BBFII than CON. Significantly highest insoluble dietary fibre and total dietary fibre shown in BBFI. Steaming resulted significant reduction in resistant starch content in BBFI as compared with the dough of BBFI I. The specific volume of BBFII and CON showed significant different compared to the BBFI. The BBFII spread ratio was significantly highest and steamer spring lowest than CON. BBFII showed significantly highest in hardness and adhesiveness values but CON was significantly highest in cohesiveness, elasticity and chewiness. L and Hue values was shown highest in CON. BBFII indicated highest acceptability score than other samples.
Protein-rich by-products from the canning industry, especially dark flesh of skipjack, have limited uses due to several factors such as darken color, susceptibility to oxidation and off flavour. Protein hydrolysates from skipjack dark flesh was produced with different type of industrial proteases (Alcalase®2.4L FG, Protamex®, Neutrase®1.5MG and Flavourzyme®500MG) for 60, 120, 180 and 240 min with level of proteases used of 0.5, 1, 1.5 and 2% per weight of raw material. The degree of hydrolysis and free tryptophan content of hydrolysate were investigated. The results shows longer time with higher concentration of enzyme has increased the degree of hydrolysis. Alcalase®2.4L FG had the highest degree of hydrolysis among all proteases followed by Protamex®, Flavourzyme®500MG and Neutrase® 1.5MG. All enzymes increase free tryptophan content linearly with the increament of protease enzyme level. The longer the hydrolysis time, the higher the content of free tryptophan produced.
MeSH terms: Body Weights and Measures; Flavoring Agents; Hydrolysis; Metalloendopeptidases; Peptide Hydrolases; Protein Hydrolysates; Subtilisins; Tryptophan
Virgin Coconut Oils (VCO) were prepared from fresh-dry (grated coconut route), chilling and thawing, enzymatic and fermentation method in this study. All of the VCO produced conformed physicochemically to the standards established by the Asian and Pacific Coconut Community (APCC) and Codex Alimentarius Commission. The highest FA (fatty acid) is lauric acid in all of the VCO and ranged from 46.36 – 48.42 %, while the principal TAG (triacylglycerol) is LaLaLa (La: Lauric) with 17.94 – 19.83 % of the total TAG. Tocopherol analysis showed the presence of beta, gamma and delta tocopherols at low levels. In all, the physicochemical, FA and TAG analyses of the VCO extracted from different methods showed some significant differences, while the tocopherol content does not differ significantly among the different types of extraction methods used.
Bacillus cereus (B. cereus) isolates are toxigenic and can cause food poisoning. Cooked rice is
a potentially hazardous food, especially in tropical countries. The aim of this study was to determine the prevalence of B. cereus and B. thuringiensis in raw and cooked rice marketed in Selangor, Malaysia. In this research combination of Most Probable Number - Polymerase Chain Reaction (MPN-PCR) was used to detect gyrB gene in B. cereus and B. thuringiensis. Five local varieties of raw rice samples were negative for B. thuringiensis but all (100%) were positive for B. cereus. A total of 115 cooked rice samples (nasi lemak, nasi briyani, nasi ayam and nasi putih) were studied for the presence of B. cereus and B. thuringiensis. Nasi ayam was found to have the highest prevalence (100%) of B. cereus compared to nasi putih (76.2%) and nasi lemak (70.4%). Nasi briyani had the lowest prevalence (50%) of B. cereus. The frequencies of B. thuringiensis were found to be 10, 30 and 35.2 % in nasi putih and nasi ayam, nasi briyani and nasi lemak, respectively. The range of B. cereus and B. thuringiensis in the samples was from < 3 to 1100 MPN/g in different samples. Maximum number of B. cereus was observed in nasi lemak, nasi briyani and nasi putih ( > 1100 MPN/g) while nasi ayam showed less contamination (460 MPN/g) with B. cereus which was significantly different (P < 0.05 ) from others. The number of B. thuringiensis in nasi lemak, nasi briyani, nasi putih and nasi ayam were found to be >1100, 93, 9.2 and 3.6 MPN/g, respectively.
The total lipid contents and the concentration of eicosapentaenoic (EPA) and docosahexaenoic
(DHA) fatty acid of fourteen selected marine, three freshwater fish species, four shellfish species and two selected canned fish species of East Coast of Peninsular Malaysia were determined. The fat content of all samples ranged from 1.01 % to 15.83 % with silver catfish reported to have the highest value. Most of the fish had fat amounts lower than 10% of their total weight. In general, DHA concentrations (50.50-165.21 µg/g) were significantly higher than EPA (11.12-55.38 µg/g) in all of the fish species analyzed. Among all marine fish species, the sixbar grouper recorded the highest concentration of DHA (165.21 µg/g) while barramundi had the highest concentration of EPA (55.38 µg/g). In conclusion, all fish and shellfish species are considered a good source of EPA and DHA, representing a very valuable essential nutrient for maintenance of human health.
Chicken fat is a potential bioresource that can be developed into a commercial product. In this study, chicken fat, which is rich in unsaturated fatty acids, including oleic acid (C18:1) and linoleic acid (C18:2), was enzymatically interesterified with corn oil to produce a soft spread. Two interesterified products, sample 16 (4% enzyme, 4:1 mole ratio of chicken fat to corn oil, 50°C and 42 h of the interesterification process) and sample 17 (4% enzyme, 2:1 mole ratio of chicken fat to corn oil, 30°C and 42 h of the interesterification process), were selected based on the highest SFC at 30oC which were close to SFC values of commercial product. A morphological study showed that the final products had smaller and less dense fat particles, which explained the lower melting temperatures and solid fat content (3.2 and 3.5% for samples 16 and 17, respectively, at 20°C) compared to the commercial products (9.7, 6.8 and 7.7% for products A, B and C, respectively, at 20°C). However, both sample 16 and 17 had similar thermal properties to a vegetable-oil-based commercial product, with melting enthalpies (ΔH) of 58.45 J/g and 71.40 J/g, and were fully melted at 31.40°C and 35.41°C, respectively.
In this study polymerase chain reaction (PCR) was used to identify yeast in domestic ragi obtained
from two local markets in Sarawak and Pahang. These ragi are normally used as a dry starter in food fermentation (tapai) for Pahang (ST2) and Sarawak (ST3) and tuak (ST1) which is an alcoholic drink in Sarawak. Universal primer, NL1 and NL4 were used as a primer in this study to amplify D1/D2 fragment. Based on the result from the sequencing and after the BLAST search of the nucleotide sequences, the strain was confirmed as Candida glabrata (FN424108.) partial 26S rRNA gene, strain IMUFRJ 51955 for ST1, Saccharomyces cerevisiae(EU285514.1) isolate 35 26S ribosomal RNA gene, partial sequence for ST2 sample and Candida glabrata (FN393990.1) partial 26S rRNA gene, strain MUCL 51244 for ST3. All these strains were found in domestic ragi used for food fermentation.
Studies have been carried out to determine the chemical (soluble solid content) and physical (firmness) parameters of locally grown Cavendish banana by near infrared (NIR) spectroscopy. NIR spectra in the wavelength region of 680-2500 nm were obtained from a total of 408 Cavendish bananas of different ripeness indices. Chemometrics using multiple linear regression (MLR) was applied to develop calibration models for prediction of firmness and soluble solid content (SSC) of Cavendish banana. Results showed that NIR spectroscopy had the feasibility for non-destructive determination of the quality of Cavendish banana. The coefficient of determination (R2) for firmness and SSC calibration models at different ripeness indices ranged from 0.78 to 0.86 and 0.75 to 0.96, respectively. The calibration models were validated using independent sets of data and prediction models developed with the root mean square error of prediction (RMSEP) ranged from 0.01 to 0.26 kgf and 0.039 to 0.788 Brix for firmness and SSC, respectively. The multi-index models showed considerable robustness but higher prediction error with RMSEP of 0.336 kgf for firmness and 0.937% Brix for SSC compared to index specific model.
Knowledge about the thermal and storage behavior of produced protein is important for the purpose of storage, transport and shelve life during industrial application. Recombinant bromelain thermal and storage stability were measured and compared to the commercial bromelain using Differential Scanning Calorimetry (DSC). Recombinant bromelain is more stable than commercial bromelain at higher temperature but the stability was reduced after 7 days of storage at 4oC. Higher energy is needed to break the bond between amino acid chains in recombinant bromelain as shown by the enthalpy obtained, suggesting that recombinant bromelain has good protein structure and conformation compared to commercial.