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81.
Tocotrienols are members of the vitamin E family that provide many nutritional benefits. Developing tocotrienol-fortified functional foods introduces vitamin E into consumers diets without changing their food habits. The purpose of this study was to compare the stability of tocotrienols in bulk form and six food matrices at a fixed dose (40 mg kg−1) under accelerated and conventional storage conditions. The delta- and gamma-tocotrienol content was measured using HPLC, and the sensory attributes were evaluated using triangle and hedonic tests. Tocotrienol in bulk powder was less stable under stressed conditions than in bulk oil, with the powders having approximately 40% and 80% reduction in δ- and γ- after storage and bulk oil with no significant degradation. HPLC analysis demonstrated that tocotrienol content remained unchanged in dry mix lemonade, yogurt, raw and UHT milk, and margarine over time; however, complete degradation of γ- and partial degradation (up to 50%) of δ-tocotrienol was observed in bread during ambient and stressed storage conditions. A significant decrease in the δ-tocotrienol relative concentration was also observed in HTST processed milk samples. Tocotrienol addition was not perceived, and no significant difference in the product attributes and overall liking was reported in the discrimination sensory testing.  相似文献   
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1 Scope

Mannan oligosaccharides (MOS) have proven effective at improving growth performance, while also reducing hyperlipidemia and inflammation. As atherosclerosis is accelerated both by hyperlipidemia and inflammation, we aim to determine the effect of dietary MOS on atherosclerosis development in hyperlipidemic ApoE*3‐Leiden.CETP (E3L.CETP) mice, a well‐established model for human‐like lipoprotein metabolism.

2 Methods and results

Female E3L.CETP mice were fed a high‐cholesterol diet, with or without 1% MOS for 14 weeks. MOS substantially decreased atherosclerotic lesions up to 54%, as assessed in the valve area of the aortic root. In blood, IL‐1RA, monocyte subtypes, lipids, and bile acids (BAs) were not affected by MOS. Gut microbiota composition was determined using 16S rRNA gene sequencing and MOS increased the abundance of cecal Bacteroides ovatus. MOS did not affect fecal excretion of cholesterol, but increased fecal BAs as well as butyrate in cecum as determined by gas chromatography mass spectrometry.

3 Conclusion

MOS decreased the onset of atherosclerosis development via lowering of plasma cholesterol levels. These effects were accompanied by increased cecal butyrate and fecal excretion of BAs, presumably mediated via interactions of MOS with the gut microbiota.  相似文献   
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Pulsed vacuum osmotic dehydration (PVOD) is a widely used technique for reducing moisture content and water activity in biological products. This study aimed to analyze the effect of vacuum application (VA) on PVOD of beetroot, carrot, and eggplant slices, with respect to chemical (moisture, water activity, specific pigments, polyphenols, and sodium content), optical (color), mechanical (shrinkage, maximum stress, and elasticity), and structural (microstructure) properties. PVOD was conducted at three different vacuum pressures (0, 40, and 80 kPa, for 10 min), during a total process time of 300 min. Osmotic processing was performed at 35 °C by using a ternary osmotic solution [40% sucrose +?10% sodium chloride (w/w)]. Eggplant and carrot samples were more sensitive to VA, compared to beetroot. This was related to their porous and less compact structure. In general, VA reduced the moisture content and water activity and preserved the carotenoid content. VA caused loss of betalain and phenolic acid, favored sodium uptake, and induced significant changes in the optical, mechanical, and structural properties, compared to the osmotic processing conducted at atmospheric pressure.  相似文献   
88.
In a previous study irradiation of cowpea flours and pastes at medium (10 kGy) and high (50 kGy) doses resulted in significant changes in protein-related functional properties. To understand some of the effects of gamma irradiation on cowpea proteins in particular, we isolated proteins from cowpea flours (FPC) and pastes (PPC) treated with gamma irradiation at 2, 10, and 50 kGy and analyzed their functional, thermal and molecular properties. Nitrogen solubility index of both FPC and PPC decreased, whereas oil absorption and emulsion capacities increased significantly with increasing irradiation dose. Differential scanning calorimetry showed decreases in transition temperatures (Td) and enthalpies (ΔH), indicating a progressive denaturation of cowpea proteins with increasing irradiation. Size exclusion HPLC revealed increases in protein molecular weights, probably due to protein–protein cross-linking with irradiation in a dose-dependent manner. Reducing SDS-PAGE of FPC and PPC samples seems to suggest that the contribution of disulphide bonds to irradiation-induced cowpea protein–protein cross-linking is small.  相似文献   
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川东二叠系生物礁油气藏的地震勘探技术   总被引:10,自引:0,他引:10  
 生物礁油气藏是一种特殊的岩性油气藏,由于其地质特点的多样性和复杂性,使得生物礁的地震勘探难度很大。本文针对川东地区二叠系生物礁的地质特点和资料情况,以生物礁气藏为研究对象,从已知井井震响应特征分析出发,通过地震反射结构分析、神经网络波形分类处理、地震属性分析、三维可视化解释、多参数地震反演等多项地震特殊处理和解释方法,建立了生物礁和生物礁储层的判别模式,形成了有针对性的地震勘探配套技术。其中以伽马、补偿中子及声波为目标曲线的多参数地震反演技术对于预测和评价生物礁特别有效。  相似文献   
90.
本文用中子衍射对Nd_2(Fe_(0.9)Si_(0.1))_(14)B在室温及77K进行了测量,用衍射峰的形状分析法进行了数据拟合。结果表明,在室温,Si择优占据4c,8j_1及16k_2晶位;Nd与Fe的磁矩平行于C轴排列。在77K,Si仍择优占据上述三个晶位。算得的Nd磁矩的方向偏离C轴37.8°。  相似文献   
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