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61.
Bioassays with a variety of overripe fruits, including mango, plum, pear, and grape, and their extracts showed that odors from overripe mango were most attractive to adult vinegar flies, Drosophila melanogaster. Combined gas chromatography–electroantennographic detection (GC-EAD) analyses of solid-phase microextraction (SPME) and Tenax extracts of overripe mango odors showed that several volatile compounds, including ethanol, acetic acid, amyl acetate, 2-phenylethanol, and phenylethyl acetate elicited significant EAG responses from antennae of female flies. Most of the volatile compounds in the extracts were identified by mass spectral and retention index comparisons with synthetic standards. In cage bioassays, lures with a blend of ethanol, acetic acid, and 2-phenylethanol in a ratio of 1:22:5 attracted six times more flies than any single EAG-active compound. This blend also attracted four times more flies than traps baited with overripe mango or unripe mango. However, in field trials, the blend was not as attractive as suggested by the laboratory bioassay. 相似文献
62.
Bhesh R. Bhandari Nivedita Datta Regan Crooks Tony Howes Shane Rigby 《Drying Technology》2013,31(10):2509-2525
ABSTRACT A semi-empirical linear equation has been developed to optimise the amount of maltodextrin additive (DE 6) required to successfully spray dry a sugar-rich product on the basis of its composition. Based on spray drying experiments, drying index values for individual sugars (sucrose, glucose, fructose) and citric acid were determined, and using these index values an equation for model mixtures of these components was established. This equation has been tested with two sugar-rich natural products, pineapple juice and honey. The relationship was found to be valid for these products. 相似文献
63.
Intidhar Bouali Hajer Trabelsi Ikram Bou Abdallah Ali Albouchi Lucy Martine Stéphane Grégoire Ghaith Bouzaien Mhemmed Gandour Sadok Boukhchina Olivier Berdeaux 《Journal of the American Oil Chemists' Society》2013,90(12):1869-1876
Among oil compounds, fatty acids, tocopherols and xanthophylls (lutein and zeaxanthin) are of special interest due to their nutritional properties. The identification and quantification of these compounds in pecan nuts (Carya illinoinensis) could therefore be very useful to produce functional foods rich in compounds of this type. This paper reports studies on their accumulation and the effect of ripening on the content of these high value-added compounds. The total lipid content increased during the ripening. Saturated and polyunsaturated fatty acids decreased significantly, whereas, monounsaturated fatty acids increased during the ripening of pecan nut fruit. Maximum levels of total tocopherol (279.53 mg/kg oil) and xanthophyll (6.18 mg/kg oil) were detected at 20th weeks after the flowering date. These amounts decreased gradually as ripening advances. The early stages of pecan ripening seem to have nutritional and pharmaceutical interests. These results may be useful for evaluating the pecan nut quality and determining the optimal period when the pecans accumulated the maximum of these nutritional and healthy compounds. 相似文献
64.
Kayesh M. Ashraf T. J. Ferdous A. I. Mustafa 《Polymer-Plastics Technology and Engineering》2013,52(6):558-566
Empty fruit bunches of oil palm fibers can be used as environmentally friendly alternatives to conventional reinforcing fibers, like glass, carbon, etc. In order to improve the interfacial properties, this fiber was subjected to grafting with bulk monomer allyl methacrylate (AMA) and cured under UV radiation. It was found that UV curing enhanced the physicomechanical properties to a large extent compared to the untreated virgin fiber. Among different AMA concentration, the fibers treated with 10% monomer showed the best mechanical properties after 15 passes of UV radiation. Different additives such as urea, acrylamide, and NVP were added with the 10% AMA solution, and the effect of additives was studied. It was found that fibers treated with 2% urea showed even better PL and tensile properties than those treated only with AMA. the treated and untreated fiber samples were also subjected to various weather conditions such as simulating weather, soil, and water aging to determine the degradable properties. It was observed that the minimum loss in each case was shown by the sample treated with the formulations that contain urea as additives with AMA and that fiber aged in soil showed higher loss of weight and tensile properties than that aged in water. 相似文献
65.
Aznizam Abu Bakar Norfhairna Baharulrazi 《Polymer-Plastics Technology and Engineering》2013,52(10):1072-1079
The influence of untreated and benzoylated oil palm empty fruit bunch (OPEFB) short fiber loading on the mechanical properties of the poly(vinyl chloride) (PVC) composite was studied. Benzoylated OPEFB was produced by mixing OPEFB with NaOH solution and agitating vigorously with benzoyl chloride. The PVC resin, various additives, and OPEFB were first dry blended using a laboratory mixer before being milled into sheets on a two-roll mill at 165°C and then hot pressed into composite samples at 180°C. The tensile and impact strength of untreated and benzoylated OPEFB composites decreased whereas the tensile modulus increased with increasing fiber loading from 0 to 40 phr. However, the benzoylated OPEFB was able to improve the tensile properties and impact strength of composites when compared to the untreated fiber. The enhancement of mechanical properties showed that the treatment improved the OPEFB fiber-PVC matrix interfacial adhesion. The improvement of adhesion was clarified by SEM micrographs, the increase of water resistance, and the reduction of glass transition temperature of the composites. 相似文献
66.
Ooi Xian Zhong Nor Aziah Abdul Aziz Azhar Abu Bakar 《Polymer-Plastics Technology and Engineering》2013,52(7):705-711
In this study, two different types of tropical fruit waste flour, rambutan waste flour (RWF) and banana waste flour (BWF), were blended with polyvinyl alcohol (PVOH) by solution casting method. The structure of the blend film was characterised by Fourier Transform Infrared Spectroscopy. The tensile strength and elongation at break of tropical fruit waste flour-filled polyvinyl alcohol were lower, but the tensile modulus was higher, than that of PVOH film. At a similar blend ratio, the tensile properties of the PVOH/RWF film were higher than the PVOH/BWF film, but the PVOH/BWF film showed higher water uptake than PVOH/RWF film. 相似文献
67.
ABSTRACT An increase in moisture content in fresh fruit and vegetables results in an increase of heat capacity, thermal conductivity and thermal diffusivity. Variations of thermal properties with moisture content are linear provided the changes in moisture content are small. The way water is bounded in dried fruits and vegetables influences their thermal properties. 相似文献
68.
ABSTRACT The weight and water loss of 6 mm thick pineapple slabs (one of a six part of slice) were analyzed during osmotic dehydration in sucrose solution at different temperatures (50, 60 and 70°C), sucrose concentrations (50, 60 and 70°Bx) and pH's (6, 7 and 8), in 33 experimental design. These results were fitted to a modified Azuara equation to obtain water and sucrose diffusivity results at equilibrium condition. Mean result of water diffusivity was 1.717 × 10?5 cm2/s and sucrose diffusivity varied from 2.0 to 4.6 × 10?5 cm2/s. The results of water loss at equilibrium in pineapple slabs varied between 0.6 to 0.67 g/g of initial sample weight. The results of sucrose gain at equilibrium varied between 0.15 and 0.21 g/g of initial sample weight. The results from mathematical modeling were compared to experimental results with r 2 = 0.94. 相似文献
69.
H. Anuar S. H. Ahmad R. Rasid N. S. Nik Daud 《Polymer-Plastics Technology and Engineering》2013,52(9):1059-1063
Thermoplastic natural rubber (TPNR) hybrid composite with short glass fiber (GF) and empty fruit bunch (EFB) fiber were prepared via the melt blending method using an internal mixer type Thermo Haake 600p. The TPNR were prepared from natural rubber (NR), liquid natural rubber (LNR) and polypropylene (PP) thermoplastic, with a ratio of 20:10:70. The hybrid composites were prepared at various ratios of GF/EFB with 20% volume fraction. Premixture was performed before the material was discharged into the machine. The study also focused on the effect of fiber (glass and EFB) treatment using silane and maleic anhydride grafted polypropylene (MAgPP) as a coupling agent. In general, composite that contains 10% EFB/10% glass fiber gave an optimum tensile and impact strength for treated and untreated hybrid composites. Tensile properties increase with addition of a coupling agent because of the existence of adherence as shown in the scanning electron microscopy (SEM) micrograph. Further addition of EFB exceeding 10% reduced the Young's modulus and impact strength. However, the hardness increases with the addition of EFB fiber for the untreated composite and decreases for the treated composite. 相似文献
70.