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The objectives of this study were to study the extrusion of cross-linked waxy maize starches (CLWMS) with different cross-linking levels and their function as a secondary ingredient in extruded oat flour (OF) formulations. CLWMS (18 %) and OF (82 %) were hydrated to 20 % moisture content and subjected to twin-screw extrusion at the screw speed of 350 rpm. Low cross-linking level of CLWMS (0.05 % sodium trimetaphosphate/sodium tripolyphosphate) in OF formulation increased the void fraction and reduced the breaking strength of extrudates. The low cross-linked starch was more resistant to breakdown and had a higher pasting viscosity than the unmodified starch. Higher cross-linking levels of CLWMS restricted swelling of starch granule and increased the resistant starch level of OF formulation but had very poor structural and textural properties. Varying the level of cross-linking offers an alternative way to manipulate the structural, textural and nutritional properties of extrudates in snack and cereal applications.

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Single-screw extrusion of a fibrous-structured meat analog from soy proteins added with low-grade oyster mushroom was successful. Satisfactory extrudates were obtained at a barrel temperature of 140 °C, screw speed range of 100-160 rpm, and oyster mushroom addition at 0%, 7.5%, and 15% via factorial experiments. Single-screw extrusion equipped with a slit die successfully produced expanded oyster mushroom-soy protein extrudates. However, the increase in the oyster mushroom content significantly decreased (p ≤ 0.05) the expansion ratio of the extrudate from 1.26 to 0.98. This result indicated that adding more oyster mushroom restrained the expansion ratio. The extrudates had a medium density range (max of 1393.70 ± 6.30 kg/m3). By adding oyster mushroom, the extrudates attained a higher moisture content (range = 34.77% to 37.93%) compared with the extrudates containing the protein mixture only (range = 26.99% to 32.33%). The increase in screw speed and oyster mushroom significantly increased (p ≤ 0.05) the water absorption index. The increase in the texturization index was significantly influenced (p ≤ 0.05) by oyster mushroom addition rather than the screw speed. A defined fibrous structure supported the high texturization index and small shape of air cells observed in the extrudates.

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BACKGROUND: Mangosteen is a native fruit from Southeast Asia. It is rich in phenolic compounds such as xanthones, anthocyanins and phenolic acids. Mangosteen pericarp extract showed inhibitory activity towards pancreatic lipase and may have potential use for obesity treatment. However, there is limited study on the beneficial effects of mangosteen flesh against obesity. This study aimed to investigate the effects of Garcinia mangostana flesh (GMF) on biochemical and morphological changes in the liver and kidney of high-fat diet-induced obese rats. METHODS: Forty healthy Sprague-Dawley rats were randomised into five groups (n = 8) with four groups were fed with high-fat diet (HFD) for 10 weeks and a control group was fed with rat chow diet. Supplementation with GMF in obese rats was continued for 7 weeks starting from week 10th after the initiation of HFD at different doses (200 mg/kg, 400 mg/kg and 600 mg/kg). The positive and negative control rats were given distilled water via oral gavage. Plasma lipid profile, antioxidant enzymes and pro-inflammatory markers were determined using commercial kits. Liver and kidney structure were defined by histology. RESULTS: The rats fed with HFD for 10 weeks increased plasma LDL-cholesterol, reduced plasma glutathione peroxidase level and had significantly higher body weight compared to normal control rats (p < 0.05). Obese rats also showed elevated level of TNF-α and IL-6 after 17 weeks of HFD. Supplementation with GMF for 7 weeks in obese rats reduced their body weight, improved lipid profile, increased total antioxidant capacity and glutathione peroxidase level and lowered plasma pro-inflammatory markers (TNF-α and IL-6) (p < 0.05). In addition, GMF supplementation attenuated the abnormalities of the liver and kidney tissue caused by high fat diet. CONCLUSION: Taken together, the findings suggest that supplementation of Garcinia mangostana flesh may help in reducing body weight and has the potential to ameliorate the biochemical changes of the high fat diet-induced obesity in rats. Further studies on pharmacodynamic and pharmacokinetic are required before the results are translated to human.

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Pulsed-UV is an emerging innovation in non-thermal processing and is scarcely explored. This study introduces a combined treatment of microwave and pulsed-UV to reduce the microbial load in yellow alkaline noodle (YAN), a popular staple food among South East Asians that is easily perishable, without jeopardising its textural qualities. Results indicated that the combination of 5 s microwave (power = 900 W; frequency = 2450 MHz) and 3.5 J/cm2 pulsed-UV significantly reduced aerobic plate count and spore forming bacteria, from 637.5 to 50 CFU/g and 1500 to 100 CFU/g, respectively. In terms of textural properties, even though significant changes were detected in hardness and springiness for treated YAN kept at ambient storage as compared to control, the alterations were not prominent. Based on these observations, it is concluded that a combined treatment of microwave and pulsed-UV successfully improved the shelf life of YAN at ambient storage by 50%, from 1.0 day (control) to 1.5 days (treated sample) and by 140%, from 2.0 to 4.8 weeks at chilled storage. Current study proves the potential of microwave + pulsed-UV, a "green" hurdle treatment, to extend the shelf life of preservative-free YAN without causing major undesirable textural alterations on the noodle.

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Mangifera odorata fruit, the hybrid forms between M. indica (mango) and M. foetida (bacang), has been shown to exhibit potential antioxidant activity, and the fruit waste could demonstrate functional and nutritional potential. In the present study, the nutritional composition (proximate, sugars, vitamins and minerals analyses), the anti-diabetic activities and phytochemical profile of M. odorata peel and seed kernel were investigated for the first time. The results indicated that seed kernel rich in fat, protein, carbohydrate, and ash while peel contained significantly greater amount of fiber, minerals, ß-Carotene and ascorbic acid compared to seed kernel. The samples were then extracted using different solvents (acetone, ethanol, methanol at 60%, v/v and pure deionized water) and their anti-diabetic activities (α-amylase and α-glucosidase inhibition assay) were determined. Seed kernel had the lowest IC50 values for α-amylase and α-glucosidase inhibition assay in 60% ethanol and 60% acetone, respectively. Due to the toxic effect and high volatility of acetone, the ethanolic extracts of samples were further analyses for their phytochemical profile using high performance liquid chromatography-mass spectrometry (LC-MS) and ultra-high-performance liquid chromatography electrospray ionization orbitrap tandem mass spectrometry (UHPLC-ESI-Orbitrap-MS/MS). The most abundant compounds identified were phenolic acid, ellagic acid, and flavonoid. These findings suggest that M. odorata fruit wastes, especially the seed kernel possesses promising ability to be used as functional ingredient in the food industry.

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The objectives of this study were to determine the stability of cross-linked bonds of starch at different pH values and their effects on the pasting property of waxy maize starch cross-linked by 0.05% and 3% sodium trimetaphosphate/sodium tripolyphosphate. The cross-linked waxy maize starch (CLWMS) was slurried (40%, w/w) and subjected to alkali treatments of pH 9, 10, 11, and 12 at 40°C for 4h. The phosphorus in 3% CLWMS decreased with increasing pH and remained unchanged in 0.05% CLWMS for all pH treatments. Decreased settling volumes indicated the reduction of swelling power for the alkali-treated CLWMS at pH 11 and 12. The (31)P NMR spectra of 3% CLWMS at pH 12 showed decreased cyclic monostarch phosphate, monostarch monophosphate, and monostarch diphosphate, but significantly increased distarch monophosphate. Alkali treatments of phosphorylated cross-linked starches offer a way to manipulate the rheological properties of cross-linked starch for desired food applications.

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BACKGROUND: Jering (Archidendron jiringa) is eaten in the tropics and traditionally extolled for treating diabetes, high blood pressure and eliminating bladder stones. Jering contains an unusual amino acid-djenkolic acid (S,S'-methylenebiscysteine)-which may form sharp crystals in the urinary tract, causing pain and haematuria. This study evaluates the beneficial and toxic effects of dietary jering on tissues and organs in normal and diabetic rats. RESULTS: Dietary jering administered orally to diabetic rats significantly reduced the blood glucose in the streptozotocin-induced diabetic rats to normal levels after about 12 weeks. Jering improved the rats' appetite, body weight, organ oxidative status and number of active islets of Langerhans in both diabetic and normal rats, after 15 weeks of treatment. Although dietary jering showed beneficial effects to diabetic eye lens, lung and pancreas, it caused hypertrophy and lesions to the heart, kidney, liver, lung and pancreas of normal rats. CONCLUSION: Chronic jering consumption showed toxic effects to the heart, kidney, liver and pancreas of normal rats but produced some beneficial effects to diabetic rats.

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