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61.
Prerna Khawas 《International Journal of Food Properties》2016,19(12):2832-2853
The culinary banana peel, which is an agricultural waste available in abundance, has not been able to draw much attention in terms of its utilization. In addition to being an abundant source of functional and nutritional compounds, it also deserves to be utilized in a proper and/or better way. The aim of this study was to explore this agro-waste at different levels of maturity in order to identify the active compounds at particular stage of maturity. Phenolics, flavonoids, and radical scavenging activity were maximum at early developmental stage, whereas compounds like protein, fat, carbohydrates, and starch increased with maturity and declined at over-ripe stage. The starch present in the peel is of C-type as confirmed by x-ray diffractograms and crystalline in nature. The peel, at the edible mature stage 4, yielded a high cellulose content which could be used as a reinforcement material in high-performance biocomposites. The presence of various functional groups indicating the complex nature of the culinary banana peel was confirmed by Fourier transform infrared characterization. Scanning electron microscope micrographs revealed that microstructure of peel changes drastically and degradation of starch and other compounds occurred at the over-ripe stage. Hence, in this context, the culinary banana peel can serve as a potential biomaterial in industrial applications and can add a higher value to this locally important and underutilized crop. 相似文献
62.
Phenolic contents,antioxidant activities and potential bioaccessibilities of industrial pomegranate nectar processing wastes
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Ece Surek Dilara Nilufer‐Erdil 《International Journal of Food Science & Technology》2016,51(1):231-239
Antioxidant potential and bioaccessibility of co‐products from industrial pasteurised pomegranate nectar (PN) processing such as peel (PP), press cake (PC) and precipitate after clarification (PAC) in comparison with raw material (arils) and final products (CON and PN) were determined. Total phenolic (TPC), flavonoid (TFC), anthocyanin (TAC), tannin contents (TTC) and antioxidant activity (TAA) were determined besides identifying major phenolics and investigating in vitro bioaccessibility after gastrointestinal (GI) digestion. PP showed the highest values, except for TAC. Phenolics (12.7–43.0%) were found to be more stable than anthocyanins (0.6–2.1%) after in vitro GI digestion. PAC was found to be a better source for anthocyanins than CON and also showed higher phenolic bioaccessibility (28.8%) than PN (19.6%). PC and PAC possessed as much TPC, TFC, TTC and TAA levels as CON, with some exceptions. Therefore, these results indicated that not only PP but also PC and PAC should be valorised as a good source for phenolics and anthocyanins. 相似文献
63.
Effect of superfine grinding on physicochemical and antioxidant properties of pomegranate peel
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Chen Zhong Yuangang Zu Xiuhua Zhao Yong Li Yunlong Ge Weiwei Wu Yin Zhang Yuanyuan Li Dongjie Guo 《International Journal of Food Science & Technology》2016,51(1):212-221
Pomegranate peel powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the pomegranate peel products. Fluidised bed jet milling technology was used to process superfine pomegranate peel powder. The physical–chemical properties of coarse powder A (D50 = 413.4 μm) and B (D50 = 197.1 μm), fine powder C (D50 = 142.6 μm) and D (D50 = 41.2 μm), superfine powder E (D50 = 7.68 μm) and raw material powder (RMP) (D50 = 352.2 μm) were investigated in this study. SEM images revealed the shape and surface morphology of six pomegranate peel powders. The physical determinations showed that the smaller the powder particle size was, the greater the surface area (from 0.214 to 1.597 m2 g?1) and bulk density (from 0.653 to 0.751 g mL?1) were, the smaller the angles of repose (from 51.69° to 38.74°) and slide (from 48.32° to 34.18°) were. The water holding capacity (WHC), water‐solubility index (WSI), polyphenols and flavonoids release were significantly improved as the size of pomegranate peel particle decreased. The results of FTIR and UV indicated that grinding process would not influence chemical composition of pomegranate peel. Vitamin C (VC) and butylated hydroxytoluene (BHT) were used in DPPH scavenging activity determination, and DPPH scavenging activity was A < RMP < BHT < B < C < D < E < VC. 相似文献
64.
In this work, three residues from the food industry (coconut husk, defatted grape seed and pressed palm fiber) were subjected to subcritical water hydrolysis with the aim of producing fermentable sugars. Hydrolysis kinetics were determined using a semi-batch unit equipped with a 50 mL reactor. The process was conducted at 208 °C and 257 °C for 30 min, with water flow rate of 33 mL/min and under 20 MPa. The liquefaction degree of the raw materials increased with temperature. The total reducing sugars recovered also increased with temperature. Maximum total reducing sugars recovered for coconut husk, defatted grape seed and pressed palm fiber using SWH were 11.7%, 6.4% and 11.9% from total raw material, respectively. Coconut husk presented the highest amount of monosaccharides (3.4%), followed by pressed palm fiber (2.4%) and defatted grape seeds (0.7%). On the other hand, the degradation products that are also fermentation inhibitors increased with temperature as well. Each raw material presented a different monosaccharides and inhibitors profile, which indicates that SWH should be evaluated and optimized individually for each case. 相似文献
65.
Hyejin Yang Young-Chul Lee Kyoung-Sik Han Harjinder Singh Minseok Yoon Ji-Hae Park Chang-Won Cho Suengmok Cho 《Food chemistry》2013
Kiwifruit is one of the most popular fruits worldwide, and it has various biological properties, including antioxidant, anti-allergic, and cardiovascular protective effects. The peel of kiwifruit, which is a by-product of processing, is a good source of flavonoids; however, its bioactivity has not been widely investigated. In this study, we evaluated the hypnotic effects of green (GRPE, Actinidia deliciosa) and gold (GOPE, Actinidia chinensis) kiwifruit peel ethanol extracts and their solvent fractions, and the possible underlying mechanisms. Oral GRPE and GOPE administration (125–1000 mg/kg) produced a dose-dependent decrease in sleep latency and an increase in sleep duration in pentobarbital-treated mice. Among three different solvent fractions of GRPE and GOPE, ethyl acetate (EA) fractions had the greatest effect on sleep duration at 250 mg/kg. The total flavonoid contents of solvent fractions were proportional to sleep duration. Like diazepam (a GABAA–benzodiazepine (BZD) receptor agonist), the hypnotic effects of GRPE, GOPE, and their EA fractions were fully inhibited by flumazenil (a GABAA–BZD receptor antagonist). These results suggest that potentiation effects of GRPE and GOPE on pentobarbital-induced sleep in mice may be modulated by a GABAergic mechanism. 相似文献
66.
Ivana Tomaz Luna Maslov Domagoj Stupić Darko Preiner Danijela Ašperger Jasminka Karoglan Kontić 《分离科学与技术》2016,51(2):255-268
Grape skin contains large amounts of different flavonoids so it can be used for their recovery. Optimization of enzyme-assisted extraction of flavonoids was conducted using oenological enzyme preparations with respect to enzyme dosage, temperature, extraction time, pH, and enzyme preparation. Optimal conditions were obtained using enzyme preparation Lallzyme EX-V, at the temperature of 45°C, time of 3 h, pH 2.0, and enzyme dosage of 10.52 mg/g. The new optimized extraction method is less expensive, simple, accurate, and selective for the recovery of simple flavonoids. It is based on an environmentally-friendly extraction solvent which may provide a valuable alternative to conventional methods. 相似文献
67.
比较了活性炭吸附法和改性柚子皮吸附法对废水中铅的去除能力。实验结果表明,活性炭吸附法对废水中铅的去除率为93.3%,耗时40 min;改性柚子皮吸附法对废水中铅的去除率为87.2%,耗时90 min。活性炭吸附法比改性柚子皮吸附法的耗时少,对废水中铅的去除率更高。但活性炭吸附法的处理成本比较高,利用改性后的柚子皮对重金属进行处理,可以变废为宝,具有环保和经济双重效益。 相似文献
68.
Antioxidant ability of potato (Solanum tuberosum) peel extracts to inhibit soybean oil oxidation
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69.
Wood‐frame buildings (WFBs) are the most commonly used structural systems for residential applications in North America. Past researches have shown that WFBs are susceptible to soft‐story mechanisms. In this study, a simple, efficient, and economical retrofit strategy, which utilizes continuous pinned‐supported rigid spine columns (RSCs) over the height of the building, is proposed. The retrofit aims to provide uniform deformation through the height of the building to prevent soft‐story mechanisms. This retrofit strategy was applied to a six‐story WFB located in Vancouver, British Columbia, Canada. A three‐dimensional nonlinear finite element model of the prototype building was developed using OpenSees. A comprehensive parametric study was conducted to identify the most economical RSC design. Seismic performance of the prototype building, with and without the most economical RSC design, was assessed through extensive nonlinear time history analyses. Results showed that the proposed retrofit strategy can effectively improve the seismic behavior of WFBs to prevent soft‐story mechanisms. 相似文献
70.
橘皮精油中的主要成分D-柠檬烯具有较强的去污能力、抑菌功效以及天然芳香味。本研究以橘皮精油为有效成分,研制了一种绿色环保型洗衣液。通过单因素试验研究了洗衣液配方中AES、AEO-7的初步配比及质量分数,并采用正交试验优化了洗衣液中各组分的配比:D-柠檬烯15%,AEO-7 14%,AES 8%,乙醇8%,柠檬酸钠2%,KCl 0.25%,余量为蒸馏水。将含D-柠檬烯的洗衣液与市售LB洗衣液进行了去污效果、发泡力、pH值对比测试。结果表明,所制备的洗衣液洗涤效果优于市售LB洗衣液(去污比值大于1)。 相似文献