动态高压微射流处理对方竹笋膳食纤维理化及结构特性的影响

以方竹笋中提取的膳食纤维为研究对象，采用动态高压微射流（dynamic high-pressure micro-fluidization, DHPM）在不同压力条件（0，50，100，150，200 MPa）下进行处理，探究其对竹笋膳食纤维（bamboo shoots dietary fiber, BSDF）理化和结构特性的影响。结果表明，随着处理压力的增大，BSDF粒径先增大后减小，当处理压力为150 MPa时，粒径最小，为（370±11） nm，此条件下BSDF的持水力、持油力和膨胀力达到最大，较对照组分别提高了47.74%，50.54%，61.27%，且差异显著（P<0.05）。红外光谱分析表明DHPM处理不会改变BSDF的官能团，但会使BSDF内部的部分氢键断裂和半纤维素、木质素等发生降解；X射线衍射和热重分析表明DHPM处理不会引起BSDF的晶体结构改变，但晶体有序度会下降，进而导致其热稳定性降低；微观结构分析显示DHPM处理会使BSDF颗粒尺寸减小、表面粗糙、组织松散，且当处理压力为200 MPa时，颗粒发生团聚。综上，DHPM可以有效改善BSDF的理化性质，在膳食纤维改性方面具有一定的应用价值。     

Volatile Components of Aqueous Liquid Smokes from Vitis viniferaL Shoots and Fagus sylvaticaL Wood

Vitis vinifera L shoots and Fagus sylvatica L wood were used to obtain aqueous smoke flavouring preparations. Both flavourings have a gold colour and pleasant odour. The flavour components of both samples are extracted with dichloromethane. The identification and quantitation of the components of the extracts are carried out by means of gas chromatography/mass spectrometry, and gas chromatography with flame ionisation detection. In both preparations carbonyl derivatives are in higher concentrations than phenol derivatives. Compounds that confer sweet, burnt and pungent flavours are in higher concentrations in the Vitis vinifera L shoots smoke flavouring, and compounds that give smoky flavours are in higher concentrations in the Fagus sylvatica L wood smoke flavouring. Ratios between the concentrations of the main components are proposed as parameters in order to characterise smoke and smoke flavourings, manufactured under specific conditions, from a specific wood. Finally, the yield of some components from a fixed amount of wood is also given.     

毛竹春笋提取物抗氧化活性研究

分别对毛竹春笋甲醇、己烷、氯仿、乙酸乙酯和水提取物的抗氧化活性和总多酚含量进行了测定.结果表明,乙酸乙酯提取物具有最强的抗氧化活性(DPPH和ABTS)和最高的总多酚含量.5种提取物的抗氧化活性与其总多酚化合物含量有显著的相关性.GC-MS图谱分析表明乙酸乙酯萃取物包含多种多酚化合物,HPLC图谱证实多酚化合物主要有邻苯三酚、邻苯二酚、阿魏酸和p-香豆酸等.     

畜禽胶原蛋白竹笋复合调料的开发

本文根据复合调味料的制作原理和方法,以及竹笋类菜肴的风味特点,利用畜、禽类的新鲜杂骨、碎皮肉等原料,添加调味辅料,加工配制成鲜竹笋加工用的胶原蛋白复合调料,研究开发竹笋食品的风味类型及应用技术。     

超微化雷竹笋膳食纤维对高脂血症小鼠的影响

本实验将3 种不同方式粉碎处理的雷竹笋膳食纤维（Phyllostachys praecox shoot dietary fiber,PPDF）悬浮于纯净水中,以2.5 g/（kg?d mb）、20 mL/kg的剂量灌胃给高脂饮食诱导的高脂血症小鼠,研究不同超微化处理的PPDF对小鼠高脂血症的影响。结果表明：与基础对照组相比,高脂模型组小鼠的体质量显著增加（P＜0.05）,血清中总胆固醇（total cholesterol,TC）、甘油三酯（triglyceride,TG）、低密度脂蛋白胆固醇（low density lipoprotein cholesterol,LDL-C）浓度、动脉粥样硬化指数（atherosclerosis index,AI）及脂/体比极显著增高（P＜0.01）,高密度脂蛋白胆固醇（high density lipoprotein cholesterol,HDL-C）浓度极显著降低（P＜0.01）;血清及肝脏中超氧化物歧化酶（superoxide dismutase,SOD）活力降低,丙二醛（malondialdehyde,MDA）含量增加（P＜0.05）;小鼠粪便干硬,含水率降低,粪脂质量分数及粪胆固醇含量显著增加（P＜0.05）。与高脂对照组对比,PPDF能极显著降低小鼠的体质量及血清中TC、TG、LDL-C浓度、AI值、脂/体比,极显著增加HDL-C浓度（P＜0.01）;血清及肝脏中的SOD活力增强,MDA含量显著降低（P＜0.05）;小鼠粪便的含水率逐渐增加,粪脂质量分数及粪胆固醇含量降低（P＜0.05）。同时,在PPDF灌胃剂量相同的条件下,PPDF粒度越小对高脂血症小鼠的作用越明显,表明PPDF对高脂血症有一定的改善作用。     

低压静电场辅助冷冻对竹笋品质的影响

为研究低压静电场辅助冷冻对竹笋冻结特性的影响,以冻结曲线、硬度、水分损失率、水分迁移、冰晶形态和组织微观结构为指标,探究低压静电场辅助冷冻（－35 ℃）和普通冷冻（－35 ℃）条件下竹笋品质的变化规律。结果表明：低压静电场辅助冷冻提高了冻结效率,改变了冰晶形态及分布,减轻了组织微观结构破损程度,改善了解冻汁液流失情况。与静电板间距10、20、30、40 cm处的冷冻竹笋解冻后水分损失率分别为14.16%、12.58%、9.73%、10.44%,显著低于对照组（21.01%）（P＜0.05）,硬度分别为461.19、507.48、496.65 g和455.31 g,显著高于对照组（350.70 g）（P＜0.05）。低场核磁共振分析结果表明,在低压静电场辅助冷冻下竹笋解冻后汁液流失减少,扫描电子显微镜观察结果显示,竹笋纤维排列整齐,组织微观结构保持较好。低压静电场辅助冷冻可有效改善竹笋品质,可为利用低压静电场进行果蔬的冷冻贮藏和冷链运输提供参考。     

Monitoring of the bacterial communities of bamboo shoots (Dendrocalamus latiflorus) during pickling process

The diversity and dynamics of the dominant bacterial communities arising during the pickling process of bamboo shoots (Dendrocalamus latiflorus) were investigated by nested polymerase chain reaction denaturing gradient gel electrophoresis combined with quantitative real‐time polymerase chain reaction. Results showed only several kinds of halophilic bacteria during early sampling time (0?3 days). After pickling for 7 days, Lactococcus lactis significantly increased (P < 0.05, quantities were 6.39 × 10⁵ copies μL^?1) and became the first dominant bacterium. After pickling for 14 days, Weissella sp. bands appeared and quickly became dominant on the 21st day (4.07 × 10⁶ copies μL^?1). As maturation progressed, Lc. lactis decreased in intensity whereas Weissella sp. increased in intensity. Finally, the quantities of Weissella sp. (2.50 × 10⁷ copies μL^?1) became higher than those of Lc. lactis (1.43 × 10⁷ copies μL^?1) after pickling for 56 days. The pickling process was initiated by Lc. lactis, followed by Lc. lactis and Weissella sp., and was finally succeeded by Weissella sp.     

Shoot growth on de-fruited grapevines: a physiological indicator for irrigation scheduling

A simple and inexpensive but biologically meaningful way of gauging grapevine water status that can guide irrigation scheduling is described. The growth rate of shoots on grapevines from which all fruit has been removed (de-fruited shoot growth) is presented as a sensitive indicator of vine and soil water status and we propose a procedure for irrigation scheduling based on monitoring de-fruited shoot growth and soil moisture. These guidelines were derived from corresponding measurements of de-fruited shoot growth and soil moisture potential that were undertaken at frequent intervals (generally 1 to 2 days). De-fruited shoot growth rate between 48 and 71 days after anthesis was linearly correlated with the mean moisture potential of the soil at depths of 60 cm and 90 cm in the centre of the drip-irrigated zone (r = 0.94). De-fruited shoot growth effectively ceased when soil moisture potential at these points had decreased to -70 kPa, although much of the root zone would have been even drier. De-fruited shoot growth thus shows an integrated and dynamic response to vine-available soil water that could aid irrigation scheduling.     

绿竹笋超高压处理和热处理加工品品质比较研究

本文对绿竹笋两种不同加工方法处理后绿竹笋品质的对比,发现绿竹笋经过超高压处理后,无论是从外观、营养成分保留等方面都比传统的热加工处理好,且保藏时间比热加工处理的长。