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1.
This study aimed to know the effect of adding pulp in rambutan fruit juice on the characteristics of rambutan juice during storage. Research using the CRD, the treatment were kind of pulp (mandarin and rambutan) and pulp concentration (5%, 7.5%, and 10%). The results showed that the addition of pulp significantly affect the characteristics of rambutan juice (pH, vitamin C, total acid) during storage. Pulpy juice with the most prefered was addition of rambutan pulp as much as 7.5% (w/v) and the addition of citrus pulp as much as 7.5% (w/v) with the score of 3-4 (moderate like - like). 相似文献
2.
E.R. Weiss R.J. Braddock R.M. Goodrich J.F. Gregory III J. Pika 《Journal of food science》2003,68(6):2146-2149
ABSTRACT: Screening commercial cold-pressed oils revealed the presence of terpene chlorohydrins, which may have quality and safety implications for end-users. Concentrations of (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol in some citrus essential oils ranged from less than 1 to 140 ppm. More than half of the oils tested contained less than 2 ppm of (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol. A pilot plant study used different concentrations of chlorinated water during the oil-recovery process. Cold-pressed oil, produced from a 30-ppm chlorine solution, contained (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol at detection threshold. The presence of (1R, 2R, 4R)-2-chloro-8- p -menthen-1-ol in citrus essential oils results from processing conditions and can be reduced through the reduction of chlorine levels in treatment water. 相似文献
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4.
ABSTRACT The mixture of citrus fruits (orange, grapefruit, mandarin, and lemon) wastes was utilized to obtain high surface area activated carbon (AC) by H3PO4 activation. The production conditions were optimized and the optimum conditions were determined. The optimal-activated carbon (CFWAC) was characterized by various physicochemical techniques. CFWAC was also used as a sorbent for Pb (II) ions from water. Batch experiments were performed to explore the adsorption capacity and mechanism. The Langmuir isotherm and pseudo-second-order kinetic model showed good fitness to the experimental data. The maximum Pb (II) adsorption capacity of CFWAC was found to be 163.93 mg/g. 相似文献
5.
Jay R Hoffman Jie Kang Nicholas A Ratamess Peter F Jennings Gerald Mangine Avery D Faigenbaum 《Journal of the International Society of Sports Nutrition》2006,3(1):35-7
Background
The purpose of this study was to examine the effect of nutritionally enriched JavaFit™ (JF) coffee (450 mg of caffeine, 1200 mg of garcinia cambogia, 360 mg of citrus aurantium extract, and 225 mcg of chromium polynicotinate) on resting oxygen uptake (VO2), respiratory exchange ratio (RER), heart rate (HR), and blood pressure (BP) in healthy and physically active individuals. 相似文献6.
7.
Identification and fermentation optimization of protopectinase-overproducing strain Aspergillus niger CD-01 for pectin production 总被引:1,自引:1,他引:0
In order to solve the citrus peel resource waste problem and minimize the drawbacks of chemical extraction of pectin, a protopectinase-overproducing
strain CD-01 for pectin production was isolated from a pit soil dumped with perished orange in Changde City, Hunan Province
of China. The strain CD-01 had the same morphology and 28S rRNA gene sequence (FJ184995) as that of Aspergillus niger (ATCC 64028). It was thus identified and named as Aspergillus niger CD-01. The fermentation condition was optimized based on L9(34) orthogonal experimental design and the variances analyses. The results show that the optimal condition for producing pectin
is as follows: time 36 h, temperature 35 °C, pH 5, and urea as the nitrogen source. Under this condition, the pectin yield
can reach up to 24.5%. This shows a great potential of Aspergillus niger CD-01 in pectin extraction from citrus.
Foundation item: Projects(50621063, 50674101) supported by the National Natural Science Foundation of China 相似文献
8.
针对目前柑橘病虫害图像数据集较少,病虫害目标复杂、散漫,难以自动定位分割的问题,提出了一种基于超像素快速模糊C均值聚类(SFFCM)与支持向量机(SVM)的农业柑橘病虫害区域分割方法。该方法充分利用了SFFCM快速、鲁棒的优点,且融合了空间信息的特点,同时避免了传统SVM在图像分割上需要人工选择样本的缺点。首先,利用改进的SFFCM分割算法对待分割图像进行预分割,得到前景和背景区域;接着利用形态学中的腐蚀和膨胀操作对前景和背景区域进行缩小,然后自动选取训练样本进行SVM模型训练;最后用训练好的SVM分类器完成整幅图像的分割。将所提方法与快速鲁棒模糊C均值聚类(FRFCM)、原始SFFCM及边缘引导网络(EGNet)这三种方法进行实验对比,结果表明所提方法的平均召回率为0.937 1,平均精确率为0.941 8,平均准确率为0.930 3,均明显优于对比算法。 相似文献
9.
利用柑桔加工废弃物制取糖蜜及乙醇 总被引:3,自引:0,他引:3
柑桔加工废弃物约占果实质量的50%,含大量糖分,适宜制备糖蜜和发酵生产乙醇.研究了用废弃物制取糖蜜及生产乙醇的工艺和条件.结果表明,柑桔皮渣制取糖蜜时,生石灰的适宜添加量为0.3%,制得的可溶性固形物为40%的糖蜜,总糖含量为34%.对pH值、糖度、接菌量和温度等影响发酵的主要因素做单因素研究基础上开展了正交试验,得到柑桔糖蜜发酵的较佳工艺条件为:发酵液的初始pH 5.0,初始含糖量25%,接种量3×107个/mL,温度保持在30℃,静置发酵.由此获得含量为10.6%的乙醇产品,为探索用柑桔糖蜜生产燃料乙醇提供了参考. 相似文献
10.
基于机器人采摘的柑橘机械特性研究 总被引:1,自引:0,他引:1
柑橘果实的机械特性,是设计针对柑橘采摘机器人末端执行器的重要依据.该研究利用弹性力学的赫芝(Hertz)理论对柑橘果实的受力与变形量的关系进行了理论分析,并通过对成熟柑橘进行匀速加压试验验证了该理论的分析结果,同时得到了该类柑橘果实的抗压机械特性.另外,还通过实验进一步分析研究了柑橘果实与硅胶材料之间的摩擦特性和柑橘果柄的切割特性,从而为设计实现柑橘抓持与果柄切割的柑橘采摘的机器人末端执行器提供准确的依据. 相似文献