50 research outputs found

    Influence of different cultivation methods on carbohydrate and lipid compositions and digestibility of energy of fruits and vegetables

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    BACKGROUND Environmental as well as cultivation factors may greatly influence the chemical composition of plants. The main factors affecting the chemical composition of foodstuff are level and type of fertilizer (conventional and organic cultivation systems), location or soil type, and year of harvest. Organic foods are defined as products that are produced under controlled cultivation conditions characterized by the absence of synthetic fertilisers and very restricted use of pesticides. Very limited information is available regarding the impact of organic cultivation systems on the composition of carbohydrates and fatty acids of fruits and vegetables. The objective was to investigate the influence of organic and conventional cultivation systems on the carbohydrate and fatty acid composition and digestibility of the energy of apple, carrot, kale, pea, potato, andrapeseedoil. RESULTS Carbohydrate and lignin values ranged from 584 g kg−1 dry matter in kale to 910 g kg−1 DM in potato, but with significant differences in the proportion of sugars, starch, non-starch polysaccharides, and lignin between the food stuffs. Triacylglycerol was the major lipid class in pea, with 82% of total fatty acids, as opposed to apple, with only 35% of fatty acids of the ether extract. The most important factor influence in the digestibility of energy, and consequently faecal bulking, was the content of dietary fibre. CONCLUSION The cultivation system had minor impact on the carbohydrate and lipid composition in the investigated foodstuffs or on the digestibility of energy when assessed in the ratmodel. Faecal bulking was related to dietary fibre in a linear fashion

    Mineral phase analysis of deep-sea hydrothermal particulates by a Raman spectroscopy expert algorithm : toward autonomous in situ experimentation and exploration

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    Author Posting. © American Geophysical Union, 2009. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Geochemistry Geophysics Geosystems 10 (2009): Q05T05, doi:10.1029/2008GC002314.This paper demonstrates that a Raman spectroscopy, point-counting technique can be used for phase analysis of minerals commonly found in deep-sea hydrothermal plumes, even for minerals with similar chemical compositions. It also presents our robust autonomous identification algorithm and spectral database, both of which were developed specifically for deep-sea hydrothermal studies. The Raman spectroscopy expert algorithm was developed and tested against multicomponent mixtures of minerals relevant to the deep-sea hydrothermal environment. It is intended for autonomous classification where many spectra must be examined with little or no human involvement to increase analytic precision, accuracy, and data volume or to enable in situ measurements and experimentation.Support for J.A.B. was provided through a RIDGE 2000 Postdoctoral Fellowship (NSF OCE-0550331)

    Near Infrared (NIR) Fourier Transform (FT) Raman spectra of some nylons

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    By excitation at 1064 nm Raman Spectra were obtained of some commercially available polyamides (nylons). Low-frequency spectra were obtained to a Raman shift on approximately 50 cm-1. A band around 100 cm-1 is assigned to a mode involving atoms in the hydrogen bonds. Quantitative studies of the low-frequency band intensities are performed using the methylene bending vibrations around 1450 cm-1 as an internal standard. The band around 100 cm-1 might give information about hydrogen bonding (i.e. secondary structure) of polyamides
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