As a protein-rich, underutilized crop, green soybean could be exploited to produce hydrolysates containing angiotensin-I converting enzyme (ACE) inhibitory peptides. Defatted green soybean was hydrolyzed using four different food-grade proteases (Alcalase, Papain, Flavourzyme and Bromelain) and their ACE inhibitory activities were evaluated. The Alcalase-generated green soybean hydrolysate showed the highest ACE inhibitory activity (IC50: 0.14 mg/mL at 6 h hydrolysis time) followed by Papain (IC50: 0.20 mg/mL at 5 h hydrolysis time), Bromelain (IC50: 0.36 mg/mL at 6 h hydrolysis time) and Flavourzyme (IC50: 1.14 mg/mL at 6 h hydrolysis time) hydrolysates. The Alcalase-generated hydrolysate was profiled based on its hydrophobicity and isoelectric point using reversed phase high performance liquid chromatography (RP-HPLC) and isoelectric point focusing (IEF) fractionators. The Alcalase-generated green soybean hydrolysate comprising of peptides EAQRLLF, PSLRSYLAE, PDRSIHGRQLAE, FITAFR and RGQVLS, revealed the highest ACE inhibitory activity of 94.19%, 99.31%, 92.92%, 101.51% and 90.40%, respectively, while their IC50 values were 878 μM, 532 μM, 1552 μM, 1342 μM and 993 μM, respectively. It can be concluded that Alcalase-digested green soybean hydrolysates could be exploited as a source of peptides to be incorporated into functional foods with antihypertensive activity.
Rambutan seed is usually discarded during fruit processing. However, the seed contains a considerable amount of crude fat. Hence, the objective of this study was to investigate the fat properties and antinutrient content of the seed during fermentation of rambutan fruit. Results showed that the crude fat content of the seed reduced by 22% while its free fatty acid content increased by 4.3 folds after 10 days of fermentation. Arachidic acid was selectively reduced and was replaced by linoleic acid from the seventh day of fermentation onwards. Only 14.5% of triacylglycerol remained in the seed fat at the end of fermentation. The complete melting temperature, crystallization onset temperature and solid fat index at 37 °C of the fermented seed fat were higher than that of non-fermented seed fat. The saponin and tannin contents of the seed were reduced by 67% and 47%, respectively, after fermentation.
To explore new approaches of phage-based bio-process of specifically pathogenic Escherichia coli bacteria in food products within a short period. One hundred and forty highly lytic designed coliphages were used. Escherichia coli naturally contaminated and Enterohemorrhagic Escherichia coli experimentally inoculated samples of lettuce, cabbage, meat, and egg were used. In addition, experimentally produced biofilms of E. coli were tested. A phage concentration of 10(3) PFU/ml was used for food products immersion, and for spraying of food products, 10(5) PFU/ml of a phage cocktail was used by applying a 20-s optimal dipping time in a phage cocktail. Food samples were cut into pieces and were either sprayed with or held in a bag immersed in lambda buffer containing a cocktail of 140 phages. Phage bio-processing was successful in eliminating completely E. coli in all processed samples after 48 h storage at 4°C. Partial elimination of E. coli was observed in earlier storage periods (7 and 18 h) at 24° and 37°C. Moreover, E. coli biofilms were reduced >3 log cycles upon using the current phage bio-processing. The use of a phage cocktail of 140 highly lytic designed phages proved highly effective in suppressing E. coli contaminating food products. Proper decontamination/prevention methods of pathogenic E. coli achieved in this study can replace the current chemically less effective decontamination methods.
Food falsification has direct impact on public health, religious faith, fair-trades and wildlife. For the first time, here we described a multiplex polymerase chain reaction assay for the accurate identification of five meat species forbidden in Islamic foods in a single assay platform. Five pairs of species-specific primers were designed targeting mitochondrial ND5, ATPase 6, and cytochrome b genes to amplify 172, 163, 141, 129 and 108 bp DNA fragments from cat, dog, pig, monkey and rat meats, respectively. All PCR products were identified in gel-images and electrochromatograms obtained from Experion Bioanalyzer. Species-specificity checking against 15 important meat and fish and 5 plant species detected no cross-species amplification. Screening of target species in model and commercial meatballs reflected its application to detect target species in process foods. The assay was tested to detect 0.01-0.02 ng DNA under raw states and 1% suspected meats in meatball formulation.
The analysis of aflatoxins (B1, B2, G1 and G2) and ochratoxin A (OTA) was performed in processed spices marketed in Penang, Malaysia, using immunoaffinity columns and HPLC equipped with fluorescence detector (HPLC-FD). The processed powdered spices analysed include dried chilli, fennel, cumin, turmeric, black and white pepper, poppy seed, coriander, 'garam masala', and mixed spices for fish, meat and chicken curry. Two different studies were carried out. The limit of detection (LOD) was 0.01 ng g(-1) for each aflatoxin (AF) and 0.10 ng g(-1) for OTA (signal-to-noise ratio = 3:1). In the first study, 34 commercial processed spices analysed with a mean level, range and incidence of positive samples for total AF were 1.61 ng g(-1), 0.01-9.34 ng g(-1) and 85%, respectively, and for AFB1 were 1.38 ng g(-1), 0.01-7.68 ng g(-1) and 85%, respectively. The mean level, range and incidence of positive samples for OTA were 2.21 ng g(-1), 0.14-20.40 ng g(-1) and 79%, respectively. Natural co-occurrence of AF and OTA was found in 25 (74%) samples. In the second study of 24 commercial processed spices, the mean level, range and incidence of positive samples for total AF were 8.38 ng g(-1), 0.32-31.17 ng g(-1) and 88%, respectively, and for AFB1 were 7.31 ng g(-1), 0.32-28.43 ng g(-1) and 83%, respectively. Fifteen positive samples for total AF and two positive samples for OTA exceeded the permissible Malaysian limit of 5 ng g(-1). Contamination of both mycotoxins in spices may represent another route of exposure to consumers due to their frequent and prolonged consumption, as spices are common ingredients in popular dishes among Asian countries.
Volatile compounds play a key role in determining the sensory appreciation of vegetable oils. In this study a systematic evaluation of odorants responsible for the characteristic flavour of roasted tigernut oil was carried out.
This study aimed to develop an optimal continuous procedure of lipase-catalyzes transesterification of waste cooking palm oil in a packed bed reactor to investigate the possibility of large scale production further. Response surface methodology (RSM) based on central composite rotatable design (CCRD) was used to optimize the two important reaction variables packed bed height (cm) and substrate flow rate(ml/min) for the transesterification of waste cooking palm oil in a continuous packed bed reactor. The optimum condition for the transesterification of waste cooking palm oil was as follows: 10.53 cm packed bed height and 0.57 ml/min substrate flow rate. The optimum predicted fatty acid methyl ester (FAME) yield was 80.3% and the actual value was 79%. The above results shows that the RSM study based on CCRD is adaptable for FAME yield studied for the current transesterification system. The effect of mass transfer in the packed bed reactor has also been studied. Models for FAME yield have been developed for cases of reaction control and mass transfer control. The results showed very good agreement compatibility between mass transfer model and the experimental results obtained from immobilized lipase packed bed reactor operation, showing that in this case the FAME yield was mass transfer controlled.
The present study was aimed at utilizing defatted rice bran (DRB) protein as an iron-binding peptide to enhance iron uptake in humans. DRB samples were treated with Alcalase and Flavourzyme, and the total extractable peptides were determined. Furthermore, the iron-binding capacities of the DRB protein hydrolysates were determined, whereas iron bioavailability studies were conducted using an in vitro digestion and absorption model (Caco-2 cells). The results showed that the DRB protein hydrolysates produced by combined Alcalase and Flavourzyme hydrolysis had the best iron-binding capacity (83%) after 90 min of hydrolysis. The optimal hydrolysis time to produce the best iron-uptake in Caco-2 cells was found to be 180 min. The results suggested that DRB protein hydrolysates have potent iron-binding capacities and may enhance the bioavailability of iron, hence their suitability for use as iron-fortified supplements.
An experimental nanosilver-coated low-density polyethylene (LDPE) food packaging was incubated with food simulants using a conventional oven and tested for migration according to European Commission Regulation No. 10/2011. The commercial LDPE films were coated using a layer-by-layer (LbL) technique and three levels of silver (Ag) precursor concentration (0.5%, 2% and 5% silver nitrate (AgNO3), respectively) were used to attach antimicrobial Ag. The experimental migration study conditions (time, temperature and food simulant) under conventional oven heating (10 days at 60°C, 2 h at 70°C, 2 h at 60°C or 10 days at 70°C) were chosen to simulate the worst-case storage period of over 6 months. In addition, migration was quantified under microwave heating. The total Ag migrant levels in the food simulants were quantified by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). Mean migration levels obtained by ICP-AES for oven heating were in the range 0.01-1.75 mg l(-1). Migration observed for microwave heating was found to be significantly higher when compared with oven heating for similar temperatures (100°C) and identical exposure times (2 min). In each of the packaging materials and food simulants tested, the presence of nanoparticles (NPs) was confirmed by scanning electron microscopy (SEM). On inspection of the migration observed under conventional oven heating, an important finding was the significant reduction in migration resulting from the increased Ag precursor concentration used to attach Ag on the LDPE LbL-coated films. This observation merits further investigation into the LbL coating process used, as it suggests potential for process modifications to reduce migration. In turn, any reduction in NP migration below regulatory limits could greatly support the antimicrobial silver nanoparticle (AgNP)-LDPE LbL-coated films being used as a food packaging material.
Four formulations of burgers, prepared with 65% lean meat and 15% fat consisting of RBD palm stearin (PS), Socfat 4000P and Socfat 4100P and beef fat (BF) as control were evaluated for solid fat content (SFC), slip melting point (SMP), cooking loss, proximate analysis (moisture, fat and protein), colour, i.e. lightness ('L'), redness ('a') and yellowness ('b'), free fatty acid (FFA), iodine value (IV), thiobarbituric acid (TBA) and texture profile analysis (TPA). Sensory evaluation was carried out for texture, juiciness, aroma, oiliness and overall acceptance. SFC and SMP for raw and cooked SF4000P beef burgers were closest to BF control burgers, falling into the range of 35-40 degrees C. Cooking loss was highest for PS burgers, there were no significant differences (P > 0.05) amongst BF, SF4000P and SF4100P burgers. Proximate analysis on raw burgers showed SF4000P to contain high fat and lowest moisture contents. Objective textural measurements using texture profile analysis (TPA) for all cooked burgers showed no significant differences (P > 0.05) for springiness and cohesiveness. Variation of values among the formulations for hardness, gumminess and chewiness are explained by the differences of SFC for beef burgers with various types of fats. Raw and cooked PS burgers have the lightest 'L' values compared with other fat-substituted burgers while BF, SF4000P and SF4100P indicated no significant differences (P > 0.05) for 'L', 'a' and 'b' values. Beef fat showed the highest amount of free fatty acids (FFA) compared to palm oil samples. For the iodine value (IV), SF4000P showed the highest value which means that it contained the highest level of unsaturated fatty acids followed by PS, BF and SF4100P successively. SF4000P had the highest TBA values followed successively by BF, PS and SF4100P. For sensory evaluation, PS burgers had the least oily taste. This may be due to its high cooking loss. Taste panelists could not differentiate burgers with substituted vegetable fats against the control burgers.
For application to the analysis of aflatoxins (AF) in commercial peanut and corn products, the ISOLUTE multimode column (IMC, solid phase multifunctional column) method was validated by comparing with the modified Florisil column (MFC) method. Twenty-two peanut and eight corn products from Malaysia and the Philippines were analysed for AFB1, AFB2, AFG1 and AFG2 firstly by the MFC method and then by the IMC method. For peanut products, 14 out of 22 samples were positive by the two methods in the range of 1-378 micrograms/kg of AF, and correlation coefficients (r) for AFB1 and AFB2 were 0.987 and 0.997, respectively. For corn and corn products, all the samples were positive in the range of 1-130 micrograms/kg, and r values were 0.992 and 0.805 for AFB1 and AFB2 respectively. Thus, the results were significantly (p < 0.01) in close agreement, particularly for lower range of 1-50 micrograms/kg of AF concentrations in all the samples. For the occurrence of AF, 11 (65%) of peanut products from Malaysia were contaminated with AF at a mean level of 50 micrograms/kg (maximum 180 micrograms/kg) and two (40% products from the Philippines were contaminated with as high as 375 micrograms/kg and 177 micrograms/kg of AF, respectively. All the corn products from the Philippines were contaminated with AF at a mean level of 44 micrograms/kg (maximum 130 micrograms/kg). Contamination of commercial foods with high levels of AF is a very important issue to both the countries since these foods are very popular among children.
We conducted 2 case-control studies with Malaysian and Hong Kong Chinese and investigated the association between salted fish intake and nasopharyngeal carcinoma (NPC). Both studies show a highly significant association between salted fish intake, especially during childhood, and NPC. Furthermore, from our results we estimate that the majority of NPC cases occurring in the southern Chinese can be attributed to their consumption of this food early in life.
The influence of dietary lecithin at doses of 0, 4, 20 or 80 g/kg fed to finisher gilts for six weeks prior to slaughter on growth performance, carcass quality and pork quality was investigated. M. longissimus lumborum (loin) was removed from 36 pig carcasses at 24h post-mortem for Warner-Bratzler shear force, compression, collagen content and colour analyses. Dietary lecithin increased dressing percentage (P=0.009). Pork chewiness and collagen content were decreased by dietary lecithin (P<0.05, respectively), suggesting that improved chewiness may be due to decreased collagen content. However, dietary lecithin had no effect on shear force, cohesiveness or hardness (P>0.05, respectively). Dietary lecithin reduced loin muscle L* values and increased a* values (P<0.05, respectively) but no changes on b* values (P=0.56). The data showed that dietary lecithin improved dressing percentage and resulted in less chewy and less pale pork.
Introduction: A prebiotic such as inulin is a well-known functional plant food ingredient. It is capable of stimulating growth of beneficial bifidobacteria in the intestine thus protecting against intestinal infections, preventing constipation, increasing mineral absorption, reducing the incidence of colon cancer, and producing B vitamins. Inulin added to food therefore has to be stable during food processing especially against heat treatment, low pH and Maillard reaction. Methods: Newly developed dark chocolate, DC-1, containing inulin (replacing sugar component) as an added value, was stored at 18oC, 60% relative humidity and 25oC, 80% relative humidity (RH) to determine shelf life stability compared to control dark chocolate, DC-0 (with high content of sugar). Sensory evaluation (quantitative descriptive analysis), water activity (aw), microbiological content and presence of inulin after storage of the prebiotic chocolate under both conditions were evaluated to determine shelf life. Results: The DC-1 chocolate had at least 12 months of shelf life at 18oC, 60% RH with better acceptance than DC-0; moreover, it did not experience microbiological and inulin content changes. At 25oC, 80% RH, the growth of Aspergillus sp. was observed on the surface of both DC-0 and DC-1 with aw >0.50 after a 2-month storage. Conclusion: Shelf life stability of DC-1 is almost similar to DC-0.
Rice bran, a by-product of the rice milling process, has emerged as a functional food and being used in formulation of healthy food and drinks. However, rice bran is often contaminated with numerous mycotoxins. In this study, a method to simultaneous detection of aflatoxins (AFB1, AFB2, AFG1, and AFG2), ochratoxin A (OTA), deoxynivalenol (DON), fumonisins (FB1 and FB2), sterigmatocystin (STG), T-2 toxin, HT-2 toxin, diacetoxyscirpenol (DAS) and zearalenone (ZEA) in rice bran was developed, optimized and validated using dispersive liquid-liquid microextraction (DLLME) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). In DLLME, using a solvent mixture of methanol/water (80:20, v/v) as the dispersive solvent and chloroform as the extraction solvent with the addition of 5% salt improved the extraction recoveries (63-120%). The developed method was further optimized using the response surface methodology (RSM) combined with Box-Behnken Design (BBD). Under the optimized experimental conditions, good linearity was obtained with a correlation coefficient (r2) ≥ 0.990 and a limit of detection (LOD) between 0.5 to 50 ng g-1. The recoveries ranged from 70.2% to 99.4% with an RSD below 1.28%. The proposed method was successfully applied to analyze multi-mycotoxin in 24 rice bran samples.
3-Monochloropropane-1,2-diol (3-MCPD) esters and glycidyl esters (GE) are heat-induced contaminants which form during oil refining process, particularly at the high temperature deodorization stage. It is worth to investigate the content of 3-MCPD and GE in fries which also involved high temperature. The content of 3-MCPD esters and GE were monitored in fries. The factors that been chosen were temperature and duration of frying, and different concentration of salt (NaCl). The results in our study showed that the effect was in the order of concentration of sodium chloride food during frying should be monitored.
Meat tenderness is one of the most important organoleptic properties in determining consumer acceptance in meat product marketability. Therefore, an effective meat tenderization method is sought after by exploring plant-derived proteolytic enzymes as meat tenderizer. In this study, a novel protease from Cashew was identified as a new alternative halal meat tenderizer. The extraction of cashew protease was optimized using response surface methodology (R2 = 0.9803) by varying pH, CaCl2 concentration, mixing time, and mass. pH 6.34, 7.92 mM CaCl2 concentration, 5.51 min mixing time, and 19.24 g sample mass were the optimal extraction conditions. There was no significant difference (n = 3; p
Background and Objective : Johor was affected by the worst flood in 100 years in December 2006 and again in January 2007. The concern that improper sanitary facilities and contaminated water supply at relief centres would result in contaminated food made monitoring of food hygiene vital. The objective of this paper is to describe food hygiene surveillance activities carried out in flood relief centres and flood affected areas and the challenges faced in carrying out these activities.
Methodology : The food hygiene surveillance activities were carried out by the Assistant Environmental Health Officers (AEHO) in the districts. Among the surveillance activities carried out are inspection of food preparation areas in relief centres, inspection of food premises in flood affected areas and food sampling. Premise inspections were carried out using a specific inspection format. Food samples taken were sent to Public Health Laboratory, Johor Bahru for microbiological analysis. Anti typhoid vaccination for food handlers were also carried out. Apart from that, observations made by the health teams were alsotaken into account.
Results : A total of 3,159 food preparation areas in relief centres were inspected. During the same period, a total of 2,317 food premises in flood affected areas were inspected as soon these premises started operating after the floods. Inspections showed that 69 food preparation areas in relief centres and 181 food premises in flood affected areas had unsatisfactory hygiene. A total of 1,566 holding samples were taken and 425 samples were sent to the laboratory for analysis. Forty-six of the samples analysed were found to be positive for pathogenic bacteria such as e. coli, staphylococcus aureus and salmonella.
Conclusion : The health personnel from the Johor Health Department in various districts carried out an excellent job in ensuring food safety during the floods. There were no outbreaks of food poisoning. However analysis of food samples taken during the floods did show the presence of pathogenic organisms but probably their numbers were not high enough to cause any food poisoning. The promotion and enforcement of food hygiene requirements should be carried out continuously to ensure that every individual understands the need for hygiene and food safety during disaster situation such as flood.
Vinegars are liquid products produced from the alcoholic and subsequent acetous fermentation of carbohydrate sources. They have been used as remedies in many cultures and have been reported to provide beneficial health effects when consumed regularly. Such benefits are due to various types of polyphenols, micronutrients and other bioactive compounds found in vinegars that contribute to their pharmacological effects, among them, antimicrobial, antidiabetic, antioxidative, antiobesity and antihypertensive effects. There are many types of vinegars worldwide, including black vinegar, rice vinegar, balsamic vinegar and white wine vinegar. All these vinegars are produced using different raw materials, yeast strains and fermentation procedures, thus giving them their own unique tastes and flavours. The main volatile compound in vinegar is acetic acid, which gives vinegar its strong, sour aroma and flavour. Other volatile compounds present in vinegars are mainly alcohols, acids, esters, aldehydes and ketones. The diversity of vinegars allows extensive applications in food.
Consumers' demand is increasing for safe foods without impairing the phytochemical and sensory quality. In turn, it has increased research interest in the exploration of innovative food processing technologies. Cold plasma technology is getting popularity now days owing to its high efficacy in decontamination of microbes in fruit and fruit-based products. As a on-thermal approach, plasma processing maintains the quality of fruits and minimizes the thermal effects on nutritional properties. Cold plasma is also exploited for inactivating enzymes and degrading pesticides as both are directly related with quality loss and presently are most important concerns in fresh produce industry. The present review covers the influence of cold plasma technology on reducing microbial risks and enhancing the quality attributes in fruits.