设计优化微波辅助法提取草石蚕中水苏糖

以干品草石蚕粉末为原料,对微波辅助法提取草石蚕中水苏糖的工艺条件进行优化.探究提取温度、微波功率、料液比及提取时间对水苏糖提取率的影响,通过四因素三水平的响应面分析法优化微波辅助法的提取工艺.当微波功率400 W、提取时间5.6 min、提取温度60℃,料液比1∶25 mg/mL时,水苏糖提取率是41.18％,与模型高...     

油茶籽多糖微波辅助提取及纯化

对油茶籽多糖微波辅助提取和纯化条件进行了研究.结果表明,微波辅助提取方法优于单纯热水提取法,其最佳提取条件为:料液比1:5,微波功率600 W,提取时间9 min,pH 6.较佳的纯化条件为:将提取得到的粗多糖1.00 g溶于100 mL热水中配成多糖溶液,采用三氯乙酸对其进行脱蛋白,双氧水进行脱色处理.6%三氯乙酸脱蛋白,添加量为多糖溶液体积的20%;30%双氧水脱色.添加量为多糖溶液体积的2%.     

膜分离技术在水苏糖提取中的应用

以地黄为原材料提取水苏糖,在榨汁浸提的基础上利用膜分离技术去除杂质以纯化水苏糖溶液,并探讨了水苏糖的提取与纯化工艺条件。试验分为水苏糖浸提、提取液脱色、膜分离纯化三部分依次进行。首先通过单因素试验探究影响水苏糖含量的浸提因素,以此为基础设计正交试验,得到了最佳的水苏糖提取条件。此后利用活性炭对水苏糖提取液脱色,最后利用纳滤膜及反渗透膜纯化、浓缩脱色液。通过探究纳滤膜的最佳操作条件提高了水苏糖含量。最终确定水苏糖最佳的浸提条件为固液质量比1︰12、浸提温度50℃、浸提时间60 min;最佳的纳滤膜纯化条件为操作压力0.12 MPa,料液温度35℃,料液稀释比1︰8 (kg/L),此条件下水苏糖的含量达到了58.84%。     

微波辅助提取莲子心多糖的工艺优化及其抗氧化活性研究

以莲子心为原料,去离子水作为溶媒,采用响应面法优化微波辅助提取莲子心多糖的工艺。利用单因素试验优化AB-8大孔树脂脱色工艺,以DPPH自由基、ABTS+自由基和超氧阴离子自由基清除能力评价莲子心多糖的抗氧化性能。结果表明,微波辅助提取莲子心多糖的最佳提取工艺为微波时间4.5 min、微波功率680 W、液料比28∶1（mL/g）,此时多糖得率为（4.84±0.11）%。单因素优化后的大孔树脂脱色工艺为大孔树脂添加量4 g、脱色时间60 min、脱色温度50℃。抗氧化活性试验结果表明,莲子心多糖具有较好的DPPH自由基、ABTS+自由基和超氧阴离子自由基清除能力,IC50值分别为 0.472、0.395、0.686 mg/mL。     

微波提取香蕉茎干中水溶性膳食纤维的工艺研究

探讨了以香蕉茎干为原料,用微波提取水溶性膳食纤维的工艺及其操作条件,并与直接水提法进行比较。结果表明,微波法最佳工艺条件为提取时间2min、提取功率900W、液料比为2ml/g、pH4,此条件下SDF 干基产率达到9.86%。微波法工艺明显优于直接水提法。     

复合酶协同微波处理提取紫背天葵叶片总黄酮工艺

目的:以紫背天葵叶片为原料,研究复合酶(纤维素酶和果胶酶)协同微波处理提取紫背天葵叶片中黄酮类物质,以及每个叶期不同叶片中黄酮类物质提取的工艺条件。方法:采用单因素及正交试验对复合酶水解后微波提取与直接微波提取总黄酮的效果进行对比试验。结果:将紫背天葵叶片50℃烘干,粉碎过80目筛,料水比1∶15(W∶V),加入0.2%果胶酶和0.05%纤维素酶,55℃水解40 min,再加入体积分数60%乙醇作提取剂,料液比1∶30,微波功率360 W,温度70℃下处理20 min后,所得浸提液中总黄酮含量比直接微波处理提高近30%。紫背天葵不同叶期、不同叶片黄酮类物质含量的规律为展开叶和成熟叶中总黄酮含量较高,幼叶次之,老叶中最低。结论:优化的工艺简便可行,提取率高,为紫背天葵黄酮类物质提取工艺的产业化提供理论依据。     

微波辅助提取安梨皮渣中多酚类物质工艺优化

试验以安梨皮渣为原料,研究了微波辅助和常规溶剂法浸提安梨皮渣中的多酚物质的工艺条件。通过单因素试验和正交试验,研究了微波功率、微波处理时间、溶剂浓度、料液比及浸提时间等因素对多酚浸提量的影响,结果表明,按料液比1︰30(g/m L)加入50%乙醇,微波功率540 W处理50 s,再于60℃水浴浸提20 min,安梨皮渣中多酚类物质的提取量可达9.322%,比直接采用50%乙醇60℃提取40 min所得多酚类物质量5.227 mg/g高出78.43%;对两种方法提取的多酚类物质紫外扫描结果显示,微波处理对多酚类物质的分子结构无破坏作用。     

臭氧深度氧化处理制浆造纸废水的研究

研究了用臭氧法深度处理制浆造纸废水的工艺条件。包括臭氧与废水量的比与处理效果的关系,臭氧接触反应时间与处理效果的关系以及臭氧脱色机理的初探。结果表明：臭氧与废水接触时间为5min、pH值8左右、臭氧的浓度为42.55mg/L时,废水CODCr的去除率为80%以上,色度的去除率为93.34%。     

栉孔扇贝多糖的提取及脱色

文中对提取栉孔扇贝多糖的工艺及对2种栉孔扇贝多糖的脱色进行了研究。利用正交实验,根据栉孔扇贝多糖的的得率,优化微波方法对栉孔扇贝多糖的提取工艺。通过对比活性炭与过氧化氢法对栉孔扇贝多糖脱色效果,确定了栉孔扇贝多糖脱色的最佳条件。结果显示:传统工艺提取最佳条件:为90℃提取3 h,固液比1∶40(g∶m L),栉孔扇贝多糖的得率为8.44%;微波提取栉孔扇贝多糖的最佳工艺条件为550 W微波功率,提取8min,固液比为1∶40(g∶m L),栉孔扇贝多糖得率为9.57%。活性炭最佳条件时的脱色率为85.8%,多糖保留率为82.7%。过氧化氢脱色法最佳时间的脱色率为82.4%,多糖保留率为67.9%。     

绿豆皮纤维素的超声波-微波联合辅助提取及其性质研究

以绿豆皮为原料,采用超声波-微波联合辅助碱法提取其中的纤维素,研究了Na OH质量分数、Na OH添加量、超声波-微波联合作用时间、微波功率及脱色时间这5个因素对绿豆皮纤维素得率、膨胀力及持水力的影响,并采用傅里叶变换红外光谱(FT-IR)对绿豆皮纤维素的微观结构进行了表征。结果表明:与碱提取法、超声波或微波单独辅助碱提取法相比,超声波-微波联合辅助碱提取法能够有效的提高绿豆皮纤维素的得率并改善其理化性质。通过单因素试验得到了绿豆皮纤维素提取的最佳工艺条件:Na OH质量分数10%、Na OH添加量15 m L/g、超声波-微波联合作用时间15 min、微波功率300 W、脱色时间90 min,在此条件下,获得的绿豆皮纤维素得率为44.91%,膨胀力为4.01 m L/g,持水力为7.16 g/g。绿豆皮纤维素的红外光谱分析结果表明,超声波-微波联合辅助碱法提取的绿豆皮纤维素特征峰没有发生明显变化,且木质素残留较少。本研究结果可以为废弃绿豆皮的再利用提供参考。     

Simultaneous depolymerization and decolorization of chitosan by ozone treatment

ABSTRACT:  Currently, depolymerization and decolorization of chitosan are achieved by chemical or enzymatic methods, which are time consuming and expensive. Ozone has been shown to be able to degrade macromolecules and remove pigments due to its high oxidation potential. In this study, the effects of ozone treatment on depolymerization and decolorization of chitosan were investigated. Crawfish chitosan was ozonated in water and acetic acid solution for 0, 5, 10, 15, and 20 min at room temperature with 12 wt% gas. In this study, the effects of ozone treatment on depolymerization and decolorization of chitosan were investigated by measuring the molecular weight, viscosity, and color of chitosan. The color of ozone-treated chitosan was analyzed using a Minolta spectrophotometer. The degree of deacetylation was determined by a colloid titration method. Molecular weight of ozone-treated chitosan in acetic acid solution decreased appreciably as the ozone treatment duration increased. Ozonation for 20 min reduced the molecular weight of the chitosan by 92% (104 kDa) compared to the untreated chitosan (1333 kDa) with a decrease in viscosity of the chitosan solution. Ozonation for 5 min markedly increased the whiteness of chitosan with a molecular weight of 432 kDa; however, further ozonation resulted in development of yellowness. In the case of the ozonation in water, there were no significant differences in the molecular weight and color between ozone-treated chitosans. This study showed that ozone can be used to modify molecular weight and remove pigments of chitosan without chemical use in a shorter time and with less cost.     

Preparation of dried chips from Jerusalem artichoke (Helianthus tuberosus) tubers and analysis of their functional properties

Jerusalem artichoke (Helianthus tuberosus L.) has recently attracted interest as a cheap form of biomass. As a food, tubers of the plant have a characteristic flavour and functional ingredients. For convenience of consumption and to prevent degradation of the high molecular weight moiety of inulin, we examined methods of preparing dried tuber chips. Chips contained inulin, other dietary fibres, and a small amount of polyphenol. The high activity of polyphenol oxidase in raw tubers suggested that blanching for more than 2 min would be required to maintain the paleness of the tubers while drying. Dried tubers had considerable water-holding capacity at low temperatures and viscosity-lowering activity on potato starch paste while heating. These results suggest that Jerusalem artichoke tubers could be more widely utilised in the food industry as a functional modifier of other materials.     

Sensory quality and appropriateness of raw and boiled Jerusalem artichoke tubers (Helianthus tuberosus L.)

BACKGROUND: The aim of the present study was to investigate the sensory attributes, dry matter and sugar content of five varieties of Jerusalem artichoke tubers and their relation to the appropriateness of the tubers for raw and boiled preparation. RESULTS: Sensory evaluation of raw and boiled Jerusalem artichoke tubers was performed by a trained sensory panel and a semi‐trained consumer panel of 49 participants, who also evaluated the appropriateness of the tubers for raw and boiled preparation. The appropriateness of raw Jerusalem artichoke tubers was related to Jerusalem artichoke flavour, green nut flavour, sweetness and colour intensity, whereas the appropriateness of boiled tubers was related to celeriac aroma, sweet aroma, sweetness and colour intensity. In both preparations the variety Dwarf stood out from the others by being the least appropriate tuber. CONCLUSION: A few sensory attributes can be used as predictors of the appropriateness of Jerusalem artichoke tubers for raw and boiled consumption. Knowledge on the quality of raw and boiled Jerusalem artichoke tubers can be used to inform consumers on the right choice of raw material and thereby increase the consumption of the vegetable. © 2012 Society of Chemical Industry     

超声波辅助复合酶提取菊糖工艺优化

以菊芋块茎为原料,采用超声波辅助复合酶酶解法进行菊糖提取工艺研究。首先通过单因素试验和Plackett-Burman筛选试验确定菊糖提取工艺中影响显著的3 个因素--超声温度、超声时间和加酶量,再利用Box-Behnken试验及响应面分析法优化最佳提取工艺条件。结果表明：最佳提取工艺条件为料液比1∶20（g/mL）、超声温度51 ℃、加酶量120 μg/g（m（果胶酶）∶m（纤维素酶）=1∶4）、超声时间25 min、pH 5.5,优化后菊糖得率为72.2%。     

Purification of jerusalem artichoke fructans and their utilisation by bifidobacteria

Ash-free white powder of fructans was prepared from the tubers of Jerusalem artichoke by hot-water extraction followed by treatment with charcoal and ion exchangers. A simple method for measuring the effects of carbon sources on the growth of bifidobacteria was developed. Bifidobacteria grew equally well in the Jerusalem artichoke fructans as in enzymically prepared fructooligosaccharides (Meioligo P). Much slower growth occurred, however, with a commercial fructan product from chicory (Fibruline).     

草石蚕糖水软罐头的研制

以甘肃庆阳产的草石蚕为试材,对草石蚕糖水罐头的工艺参数进行了研究。得出草石蚕在适时采收并清洗后,以质量分数1%的食盐溶液护色30min ,可达到较好的初护色效果;最佳去皮条件是质量分数1%的NaOH溶液,在98℃下去皮90s;再用质量分数0 2 %的NaHSO3 溶液进行二次护色30min ,可防止碱液去皮后的再褐变;通过L9(34)正交试验得出最佳的汤汁配比为,4 5 %的白砂糖、1 0 %的柠檬酸和0 2 %的CaCl2 时,可生产出风味较佳的草石蚕糖水罐头。     

Scale‐up batch fermentation of bioethanol production from the dry powder of Jerusalem artichoke (Helianthus tuberosus L.) tubers by recombinant Saccharomyces cerevisiae

This study is a first exploration of industrial bioethanol production from the dry powder of Jerusalem artichoke (Helianthus tuberosus L.) tubers by recombinant S. cerevisiae 6525. Scale‐up fermentation of bioethanol production from the dry powder of Jerusalem artichoke tubers by recombinant Saccharomyces cerevisiae 6525 was carried out at the scale of 50 and 500 L agitating fermentors. For the 50 L fermentor, 85.67 g/L of ethanol was obtained within 72 h of fermentation, and the ethanol yield was 90.1%. For the 500 L fermentor, the highest ethanol concentration of 77.00 g/L was achieved at 84 h, and the ethanol yield was 81.01%. These results indicated that a relatively high yield of ethanol could also be obtained from a scaled‐up fermentation of Jerusalem artichoke powder. Thus, it may be feasible to use a Jerusalem artichoke tuber feedstock to carry out ethanol fermentations using the recombinant S. cerevisiae 6525 for industrial production. Copyright © 2016 The Institute of Brewing & Distilling     

Enzymatic browning and after-cooking darkening of Jerusalem artichoke tubers (Helianthus tuberosus L.)

Jerusalem artichoke tubers (Helianthus tuberosus L.) undergo enzymatic browning when peeled or cut, and turn grey after boiling, due to after-cooking darkening reactions between iron and phenolic acids. In an attempt to reveal the components responsible for these discolouration reactions, sensory evaluation and instrumental colour measurements were related to contents of total phenolics, phenolic acids, organic acids and iron in three varieties of raw and boiled Jerusalem artichoke tubers harvested in the autumn and the spring. No differences were found between varieties in sensory evaluated enzymatic browning, but Rema and Draga had higher scores than Mari in after-cooking darkening. Jerusalem artichoke tubers had higher contents of total phenolics, phenolic acids and citric acid in the autumn and low contents in the spring, while it was the opposite for malic acid. None of the chemical parameters investigated could explain the discolouration of the Jerusalem artichoke tubers.     

利用菊芋菊粉制备R,R-2,3-丁二醇发酵工艺条件的优化

为了提高Paenibacillus polymyxa ZJ-9发酵菊芋菊粉制备R,R-2,3-丁二醇的产量、减少生产成本,考察了发酵温度、pH、接种量和溶氧(搅拌转速)对菌体生长繁殖、菊粉的利用率和R,R-2,3-丁二醇合成的影响。实验结果表明,Paenibacillus polymyxa ZJ-9发酵的最适温度、pH和接种量分别为30℃、6.0和8%。通过对不同搅拌转速条件下的菌体比生长速率μ_x和产物比合成速率μ_p分析,制定了一种两步溶氧控制策略发酵生产R,R-2,3-丁二醇:在发酵前24h,控制搅拌转速调控为240r/min有利于菌体生长,而24h后,控制发酵液搅拌转速调控为160r/min,能有效促进R,R-2,3-丁二醇合成,在上述条件下,R,R-2,3-丁二醇的产量高达27.83g/L,比恒定搅拌转速条件的最大值提高了10.15%。     

菊芋全粉对米发糕贮藏品质特性的影响

目的 探究菊芋全粉添加量与米发糕品质特性之间的相关性。方法 在米发糕中添加不同比例(5%、10%、15%、20%、25%)的菊芋全粉,测定其贮藏过程(0、1、3、5、7 d)中感官品质、质构特性和体外消化特性等指标,探究菊芋全粉与米发糕品质指标之间的相关性。结果 与未添加菊芋全粉的米发糕相比,菊芋全粉的添加降低了米发糕的硬度、粘性和咀嚼性,感官评分从81.91下降到70.91,而米发糕抗性淀粉从26.02%增加至34.59%。菊芋全粉的添加能有效减缓米发糕在贮藏期间质构的劣变,贮藏第7d时,添加15%菊芋全粉的米发糕感官评分(80.83)高于对照组(66.57),且添加10%菊芋全粉的米发糕抗性淀粉高达42.23%。通过相关性分析,回复值、弹性和粘聚性是影响米发糕感官品质的主要因素,其中弹性与米发糕感官评分呈极显著负相关(P<0.01)。结论 添加菊芋全粉可有效提升米发糕的感官品质及抗消化特性,并能有效减缓米发糕在贮藏期间的质构劣变,同时也丰富了米发糕品种多样性,可为菊芋资源的开发和高值化利用、发糕制品的深度研究提供理论参考。