蕨菜研究进展综述

综述了国内外蕨菜研究的现状,涉及的内容包括蕨菜中有效成分的提取与检测,黄酮类物质和多糖的毒理学,蕨菜的保鲜工艺、脱水干燥和加工技术及加工期间营养成分的变化,并对今后蕨菜的研究作了展望。     

软包装蕨菜的生产工艺研究

以新鲜蕨菜为原料,探讨了软包装蕨菜的生产工艺技术。在pH6的条件下,以锌盐为护绿剂,进行蕨菜的护色试验,取得了令人满意的结果。利用工艺生产的产品不仅保持了蕨菜原有的营养成分,还具有口感脆嫩、食用方便、保存期长的特点。     

速冻对蕨菜品质的影响及酶活性变化的试验研究

对速冻过程中蕨菜的质量指标及过氧化物酶活性变化进行了研究,发现不同的冻结速率会引起蕨菜中过氧化物酶活性发生较大幅度的变化,并对蕨菜的质量指标产生不同的影响。认为选择适宜的冻结条件是确保速冻蕨菜品质的重要环节。     

蕨菜冷冻干燥的工艺研究

研究侧重从干制蕨菜的护绿、保脆、复水性及Vc的保存率等方面,讨论了蕨菜的冷冻干燥生产工艺,并得出了蕨菜冷冻干燥的最佳工艺条件,可为技术工业化提供理论依据。     

野生蕨菜真空冷冻干燥动力学及产品特性研究

通过建立蕨菜真空冷冻干燥动力学模型,对冻干蕨菜进行真空冷冻干燥其动力学特性的研究,并从感官外观、水分含量和活度、复水特性以及主要营养成分保存情况等不同方面进行量化指标检测,对冻干蕨菜和热风干蕨菜进行比较全面的对比。结果表明:冷冻温度、真空度和装料量3种因素对蕨菜干燥效果都有不同程度的影响;验证方程的预测值与试验值基本吻合;冻干蕨菜较热风干蕨菜更接近新鲜蕨菜物理特性,风味更为浓郁,主要营养成分保存更加完整。     

蕨菜贮藏保鲜与产品开发研究现状

对近年来有关蕨菜贮藏保鲜技术和产品开发的研究进展进行了综述。详细阐述了蕨菜护色和干燥技术,总结了其产品研制工艺,并对蕨菜的采后贮藏保鲜和产品研发的今后发展趋势进行了展望。     

蕨菜饼干制作工艺的研究

以蕨菜和面粉为原料,先通过单因素试验对蕨菜粉添加量、起酥油添加量、白砂糖添加量、小苏打添加量对蕨菜饼干生产的影响进行研究,再通过L9(34)正交试验进行感官综合评定确定蕨菜饼干工艺的最佳条件。研究结果表明:蕨菜饼干的最佳配比为小麦粉:蕨菜粉:起酥油:白砂糖:小苏打=100:25:30:35:0.5,烘烤工艺以温度为200℃,烘烤10min为宜。所制得的蕨菜饼干外表厚薄均匀、颜色棕黄、口感酥脆,具有蕨菜特殊风味。     

花果山野生蕨菜多糖和黄酮的提取及含量测定

以连云港花果山野生蕨菜干粉为原料,通过正交试验选择最佳提取条件,用分光光度法测定总黄酮和多糖的含量。结果表明：蕨菜中多糖提取的最优条件为蕨菜与水料液比1:20(g/mL)、提取温度90℃、提取时间1.5h、提取次数2 次。新鲜蕨菜干粉中多糖含量为1.39%,三月枯蕨菜干粉中多糖含量为7.08%;提取蕨菜中黄酮类物质的最优条件为蕨菜与70% 乙醇比1:10(g/mL)、提取温度90℃、提取时间2h、提取次数2 次,测得新鲜蕨菜干粉中总黄酮含量为4.90%,三月枯蕨菜干粉中总黄酮含量为3.11%。     

蕨菜的随想

蕨菜在我时下谋生的永平小城,算不得是稀罕之物。位于小城中心的农贸市场,常见有卖。不过,除了仲春时节可以买到时鲜的蕨菜以外,平时能够买到的,多是经过腌制加工的酸辣蕨菜或脱水保鲜的袋装蕨菜。仲春季节,每逢集日,卖蕨菜的小摊,可以摆满市场南面那一整条长长的小巷。这段时间上市的蕨菜,大多都是从先前曾经耕种过的二荒地或轮歇地里采摘来的,粗壮、肥实、鲜嫩,一元钱一大把,非常划算。买回家后稍事加工,便可食用。     

风味蕨菜罐头的研制

以鲜嫩的蕨菜为原料,探讨蕨菜护绿最佳工艺条件及其风味蕨菜罐头生产的可行性。结果表明:蕨菜的最佳护绿工艺条件为温度95℃、漂烫时间3min、pH值4、Cu(COOH)2护绿液的浓度250mg/kg,所得到的蕨菜护绿效果最好;利用0.2%的CaCl2溶液作为蕨菜的保脆溶液能够达到比较好的保脆效果;以泡椒型和酸辣型蕨菜罐头的风味为最好。     

Bracken (Pteridium aquilinum)—toxic effects and toxic constituents

Bracken (Pteridium aquilinum L Kuhn) is one of the most successful weeds of the world. In the UK it covers almost 700 000 ha, and is expanding its area by 1–3 % per annum. Not only does bracken limit the usefulness of marginal land but toxic principles in the plant may cause serious illness and even death in stock animals consuming its rhizomes or fronds. Bracken-derived acute thiamine deficiency disorders occur in pigs and horses, and acute haemorrhagic syndrome, bovine enzootic haematuria and ‘bright blindness’ are all responsible for significant losses of livestock. A great deal of research has resulted in the isolation and identification of a number of natural components of bracken, and the evaluation of their biological effects using laboratory animal models and farm livestock has been carried out in detail. One compound contributing significantly to the toxicity of bracken is the carcinogenic and mutagenic norsesquiterpene, ptaquiloside. The effects on stock and laboratory animals of bracken, its extracts or ptaquiloside are discussed in this paper; the risk to human health from consumption of bracken fronds, milk and dairy products containing bracken carcinogens or their metabolites and drinking water supplies containing bracken leachates is considered from the standpoint of the UK and beyond. Options for the control of bracken are described briefly, and the final section indicates areas of bracken research deserving of further study.     

陕南蕨菜有效成分的分析

为了充分利用蕨菜植物资源,对陕南蕨菜的有效成份中的总脂肪、总黄酮和总多糖进行了分析,分别采用索氏提取法、比色法和苯酚-硫酸法等测定.结果表明:蕨菜中总脂肪、总黄酮总和总多糖含量分别为:2.13%,2.20%和8.22%.     

Physicochemical Properties of Starch Isolated from Bracken (Pteridium aquilinim) Rhizome

Bracken (Pteridium aquilinum) is an important wild plant starch resource worldwide. In this work, starch was separated from bracken rhizome, and the physicochemical properties of this starch were systematically investigated and compared with 2 other common starches, that is, starches from waxy maize and potato. There were significant differences in shape, birefringence patterns, size distribution, and amylose content between bracken and the 2 other starches. X‐ray diffraction analysis revealed that bracken starch exhibited a typical C‐type crystalline structure. Bracken starch presented, respectively, lower and higher relative degree of crystallinity than waxy maize and potato starches. Ordered structures in particle surface differed among these 3 starches. The swelling power tendency of bracken starch in different temperature intervals was very similar to that of potato starch. The viscosity parameters during gelatinization were the lowest in waxy maize, followed by bracken and potato starches. The contents of 3 nutritional components, that is, rapidly digestible, slowly digestible, and resistant starches in native, gelatinized, and retrograded starch from bracken rhizome presented more similarities with potato starch than waxy maize starch. These finding indicated that physicochemical properties of bracken starch showed more similarities with potato starch than waxy maize starch.     

发酵法生产灵芝-蕨渣菌质可溶性膳食纤维的工艺优化

为了获得发酵法制备灵芝-蕨渣菌质可溶性膳食纤维的最适工艺参数,以基质蕨渣比例、基质含水量和培养温度为因子,以可溶性膳食纤维得率为响应值,采用响应面试验设计进行试验。结果表明：可溶性膳食纤维最适制备条件为基质蕨渣质量分数84%、基质含水量为63%、培养温度27℃。在此条件下,可溶性膳食纤维得率的预测值为13.034%,验证实验所得可溶性膳食纤维得率为12.885%。回归方程的预测值和实验值差异不显著,所得回归模型拟合情况良好,达到设计要求。在本实验优化的条件下,以发酵法制备灵芝-蕨渣菌质的可溶性膳食纤维得率(12.885%)显著高于蕨渣原料的可溶性膳食纤维得率(1.733%)。     

蕨菜护色工艺条件优化

以凉山州新鲜蕨菜为原料,研究烫漂、护色工艺条件对蕨菜质量的影响。试验结果表明,最佳烫漂工艺条件是温度90℃,时间4 min,NaCl浓度0.5%;最佳护色工艺条件研究结果是:pH 4,Cu(COOH)2浓度300 mg/kg,时间25 min。     

Herbicides in forestry

The present use and future potential of herbicides for control of grass-herbaceous broadleaved weeds, woody weeds, heather and bracken is discussed.     

Studies on nucleotides and related compounds in plants. V. Isolation and identification of bracken nucleotides

The presence of acid-soluble nucleotides was demonstrated in bracken rhizomes. Cold trichloroacetic acid extracts of bracken had to be submitted to some eight purification steps prior to analysis. Of the nucleotide material held by an anion exchange resin uridine derivatives (UMP, UDP-glucose, UDP-galactose, UDP-xylose, UDP-arabinose, UDP-glucuronic acid and a trace of UDP) accounted for some 80% of the total. The remainder comprised guanosine (12%; GMP, GDP-mannose and GDP-fucose) and adenosine (8%; mainly ATP) compounds. A comparison of the sugar composition of the nucleotide material with that of associated soluble carbohydrates present in the rhizome (mucilage, glycoside and sucrose) is also included.     

A new,very sensitive method of assessment of ptaquiloside,the major bracken carcinogen in the milk of farm animals

We describe a new method to detect trace levels of ptaquiloside (Pta), a major carcinogen of bracken fern in biological samples such as milk from farm animals. The method involves the absorption of analyte on carbograph followed by elution with solvents mixtures. The unstable analyte is then converted into Br-Pt (II), which is specific for Pta, as it is not a natural decay product of the glycoside in aqueous media. An internal standard, the Br-pterosine-d₂, prepared in our laboratories has been used. Detection and quantification are possible with gas chromatography/mass spectrometry (GC/MS) in single ion monitoring mode (SIM). The detectable amount is in the range of ppb. The method allowed us to detect Pta not only in the milk from bracken fern-poisoned cattle but also, for the first time, in the milk from healthy farm animals such as sheep, goat, horse, and donkey mares.     

植物乳杆菌发酵对蕨菜品质的影响

以新鲜野生蕨菜为原料,接种植物乳杆菌Z17（Lactobacillus plantarum Z17）进行发酵,并以自然发酵为对照,于相同条件下发酵42 d,探究发酵过程中接种植物乳杆菌Z17对蕨菜的总酸、还原糖、pH、色度、褐变指数、咀嚼性以及黏性等理化指的影响。结果表明:接种Z17后蕨菜的pH下降速率以及还原糖含量提升的速率明显优于自然发酵;发酵过程中总酸的含量也得到了显著的提升（P<0.05）,尤其是乳酸,含量提升了2.3倍;发酵结束后,接种Z17的蕨菜与自然发酵蕨菜感官评价分别为（88.34±3.74）和（65.23±2.68),接种Z17明显提升了蕨菜的咀嚼性和硬度。综上可知,接种植物乳杆菌能够有效地缩短发酵周期、提高泡菜食用性,还有利于改善发酵蕨菜的品质。     

不同气调包装对蕨菜保鲜效果的影响

本文就气调处理对蕨菜保鲜的影响进行研究。以未处理状态下的蕨菜的作为空白对照组,6%CO_2+2%O_2、6%CO_2+6%O_2、6%CO_2+10%O_2不同比例的二氧化碳和氧气混合气体的气调包装作为实验组,研究气调保鲜对蕨菜保鲜效果的影响。通过测试保鲜后蕨菜的失重率、可溶性固形物、Vc含量、可滴定酸含量、硬度和叶绿素含量变化,分析不同气体比例蕨菜保鲜的效果,选择出最佳保鲜效果的气体比例。实验结果表明,气调保鲜减缓了蕨菜品质的下降速率。气调保鲜延长了达到可溶性固形物和叶绿素a峰值含量的时间,从原来的第4 d延长到第8 d,且可溶性固形物实验组峰值是对照组的1.56倍。14 d时6%CO_2+10%O_2可溶性固形物是对照组的1.31倍,叶绿素a含量是对照组的1.55倍。气调保鲜减缓Vc的分解,分别减缓了5%、5%、10%,其中6%CO_2+10%O_2气体比例减缓效果更明显。分析得出CO_2和O_2含量为6%、10%时,对蕨菜的保鲜效果最佳。