猪油脱色工艺的研究

对猪油脱色工艺的研究表明,干法炼制的猪油采用常规脱色工艺不能达到有效的脱色.采用二次碱炼,脱色工艺有较好的脱色效果;稀碱溶液洗涤可用于低酸值干法炼制猪油的辅助脱色;高温磷酸脱色对于干法炼制的猪油脱色效果最好,但操作条件较难把握.     

脱酸米糠毛油品质对吸附脱色综合效果的影响

采用碱炼脱酸和水蒸汽蒸馏脱酸两种不同脱酸工艺所得米糠油进行吸附脱色试验,以米糠油脱色率及谷维素、甾醇、维生素E等营养成分保留率和反式脂肪酸生成量作为考察指标,分析研究待脱色米糠油品质对吸附脱色综合效果的。结果显示,在脱色率、VE保留率和反式酸含量方面碱炼脱酸米糠油的综合脱色效果优于水蒸汽蒸馏脱酸米糠油。碱炼脱酸米糠油的最佳吸附脱色条件为:凹凸棒石为吸附剂,用影响量为油重的4%,脱色时间30 min,脱色温度110℃。在最佳工艺条件下,测得米糠油脱色率为75.08%,脱色米糠油的色泽为Y35、R2.1(罗维朋比色槽25.4 mm),满足国标三级米糠油色泽要求;谷维素保留率为88.89%(脱色前后谷维素含量分别为0.90%、0.80%、),甾醇保留率为73.87%(脱色前后甾醇含量分别为2.32%、1.71%),维生素E保留率为82.90%(脱色前后维生素E含量分别为50.57 mg/100 g、41.92 mg/100 g);与水蒸汽蒸馏脱酸米糠油相比,相同脱色条件下,脱色率提高7.84%,维生素E保留率提高7.64%,但谷维素保留率下降4.74%,甾醇保留率下降4.58%。脱色前后碱炼脱酸米糠油中未检出反式酸,水蒸汽蒸馏脱酸米糠油中反式酸含量为0.40%,脱色后反式酸含量增加了0.02%。虽然谷维素和甾醇的保留率相对降低,但两者的保留率仍达到了88.89%、73.87%,脱色油中两者含量分别为0.80%、1.71%,单就脱色过程而言,营养成分保留率还是很高的。     

脱色吸附剂对大豆脱色油返酸返色的影响

为对油脂精炼脱色加工提供参考,以活性白土、凹凸棒土以及二者复配作为脱色剂对大豆中和油进行脱色,测定脱色油的酸值、色泽,并通过返酸返色试验探究脱色吸附剂对大豆脱色油返酸返色的影响。结果表明：脱色油酸值与活性白土添加量和复配脱色剂中活性白土质量分数呈正相关,与凹凸棒土添加量呈负相关;脱色剂添加量越多,脱色效果越明显,但在活性白土或凹凸棒土添加量超过3%时,脱色效果增加较少;随活性白土或凹凸棒土添加量的增多,脱色油返酸总体呈先降后升趋势;脱色油会有不同程度的返色,与活性白土相比,凹凸棒土脱色返色程度更高。综上,在脱色过程中,通过调整脱色剂添加量和配比可在一定程度上控制成品油的返酸返色程度。     

酸活化凹土在牛羊油脱色中的应用研究

通过扫描电镜、X射线能谱、X射线衍射、傅立叶变换红外光谱和BET测试,对不同浓度的硫酸改性后的凹土进行分析.结果表明,经过合适浓度的硫酸处理的凹土可获得较好的脱色效果.对脱色前后油脂的紫外可见光谱分析表明,5%硫酸活化处理的凹土能有效地去除牛羊油中的色素.牛羊油中色素的脱除不仅与凹土比表面有关,更与合适的孔径有关.     

二次碱炼脱色工艺条件的研究

低酸价深色油脂采用二次碱炼的方法脱色,不造成中性油损失又能取得一定的脱色效果的最佳工艺条件为温度50℃,碱液浓度为8°Be′。     

低聚木糖浆二氧化硫硫漂脱色研究

利用二氧化硫对低聚木糖浆进行硫漂脱色，试验结果表明，低聚木糖浆中的部分色素能与保险粉遇水分解产生二氧化硫反应，从而达到一定的硫漂脱色效果，pH和温度对保险粉硫漂脱色的效果有较大的影响，优化的条件为：保险粉用量0．6％，7－80℃和20min,在此条件下的脱色率可达到43％。硫漂脱色的产品色泽不稳定，但经过离子交换树脂以后，产品的色泽变得稳定。     

有色绒脱色工艺的研究

在动物纤维中,有相当一部分具有天然色泽,特别是中国产量较大的一些特种动物纤维,如紫山羊绒、青山羊绒、牦牛绒、驼绒等,价格昂贵,但因其天然色泽的局限影响了花色品种的开发。采用"媒染-氧化-还原"方法对紫绒进行脱色处理,探讨了脱色助剂用量及处理工艺对脱色效果的影响。使用白度、碱溶度等指标评价脱色效果。在实验室小试的基础上进行了较大批量生产,经过数次工厂生产试验,分别确定了紫绒、青绒的工业化脱色工艺,成功地将各种有色绒毛进行了脱色处理,得到洁白的产品。     

几种脱色剂对菜籽油脱色效果的研究

以菜籽油的色泽红值和叶绿素含量为考察指标,比较了凹凸棒土、活性白土、活性炭和双氧水4种脱色剂对菜籽油在中低温(40~80℃)下的脱色效果,同时考察了凹凸棒土与活性炭、活性白土与活性炭组成的复合吸附脱色剂对菜籽油的脱色效果。结果表明:活性炭在较低添加量条件下可以获得与凹凸棒土和活性白土较高添加量相当的脱色效果;活性白土-活性炭复合脱色效果优于凹凸棒土-活性炭,在添加量为2%时,80℃下可使菜籽油的叶绿素含量降低32. 5%、70℃下使菜籽油色泽红值降低30. 6%;双氧水对于去除菜籽油叶绿素和降低色泽红值效果明显,70℃下,0. 4%双氧水(10%)使菜籽油叶绿素含量降低9. 0%、0. 6%双氧水(10%)使菜籽油色泽红值降低25. 0%。活性白土-活性炭脱色和双氧水脱色后的菜籽油品质指标均达到国标四级菜籽油水平;就单位质量浓度脱色剂的脱色效果来说,双氧水的脱色效率更高。     

玉米油脱色条件对生育酚含量影响研究

通过对脱色温度、脱色时间、脱色白土用量3个因素进行单因素及正交实验,研究脱色条件对玉米油生育酚含量的影响。结果表明:对生育酚含量影响的因素依次为脱色时间>脱色白土用量>脱色温度,当脱色时间为20 min,脱色白土用量为2.5%,脱色温度为105℃时,生育酚损失最少,损失率为9.3%,此时脱色油的色泽为Y35R3.2,色泽达到二级油标准。     

硅胶有助于提高白土脱色效果

硅胶有助于提高白土脱色效果安徽省淮南市粮科所黄显慈１概况用白土吸附脱邑除去油脂中有色物质和油中残留的部分皂、胶质等杂质。油脂脱色所需的白土数量主要取决于白土的活性、油脂的质量、对脱色油的色泽要求。人们希望用较少量白土达到脱色要求，这样可以降低油脂损耗...     

低硬度调和牛油的制备及品质分析

通过Rancimat法测定牛油—菜籽油调和油的氧化诱导时间,推算调和牛油的产品保藏期。通过质构仪测定调和牛油在室温下的硬度,确定调和牛油中两种油脂的适宜添加比例。结果表明:调和牛油氧化诱导时间为(18.92±0.10)^39.90±0.42h,氧化稳定性介于菜籽油和牛油之间。当牛油添加比为40%~60%时,调和牛油的硬度与猪油的接近。     

Influence of Enzymatic Pretreatment on the Colours of Bleached and Dyed Flax Fibres

SUMMARY

In this paper the effect of enzymatic bioscouring on the bleaching and dyeing of flax fibres was studied in comparison with conventional alkaline scouring. Enzymatic bioscouring was performed with a commercial multi-enzyme system consisting of pectinases, hemicellulases and cellulases. The enzyme and alkaline scoured flax fibres were subsequently oxidatively bleached with hydrogen peroxide and dyed with direct dye C.I. Direct Red 80 under the same conditions. The efficiency of both the scouring and bleaching processes was evaluated by weight loss and the whiteness of the bleached samples was determined according to CIE formula. The exhaustion profile of the used dye was followed on-line during the dyeing process using absorbance measurement. The colours of bleached and dyed samples were evaluated using CIELAB colour values. The residual pretreatment and dyeing baths were ecologically analysed with COD, TOC and BOD₅. The obtained results indicate that enzymatic scouring provides a lower weight loss, a higher degree of whiteness, comparable dyeing properties and is more environmentally friendly.     

潲水油氧化-吸附法脱色研究

基于潲水油理化特征,研究了双氧水、白土对潲水油脱色后的吸收光谱,建立了光谱法监控对潲水油进行双氧水氧化和活性白土吸附脱色的新方法。研究表明,25.0 g潲水油中加入3.0mL双氧水、再用1.25 g或2.50 g白土脱色时,脱色效率分别为88.1%和92.0%,若是将其放置1周,则脱色率分别可以提高到96.9%和98.1%。脱色处理后的潲水油无不良气味,可以作为洗涤产品中添加的皂化物的工业原料,具有可观的经济效益、环境效益和社会效益。     

Oxidation of cholesterol in heated tallow

Preliminary thin layer and gas chromatography data indicate that tallow cholesterol is oxidised when tallow is exposed to high temperatures (180°C) for an extended period. This may be of some significance to human health since some of these oxidation products may be angiotoxic and/or carcinogenic and tallow is used as a deep-fat frying medium in some fast-food restaurants.     

Microwave-Assisted Bleaching of Wool Fabrics

Microwave irradiation was used to reduce consumption of energy and time during bleaching of wool fabrics with hydrogen peroxide. The effect of some reaction conditions; viz. hydrogen peroxide concentration, treatment time, presence of stabilizer, on degree of whiteness imparted to bleached wool, was studied systematically. Comparative study between bleaching of wool using microwave irradiation and conventional heating was undergone. The effect of bleaching of wool on its morphological structure was assigned by scanning electron microscopy. The change in some chemical and physicomechanical characteristics of bleached wool was monitored; namely whiteness index, alkali solubility, wettability, critical surface area, tensile strength, and elongation at break, of the treated as well as untreated fabrics were measured. The microwave-assisted bleaching of wool resulted in improved degree of whiteness comparable to that is obtained using conventional heating method. However, the microwave-assisted bleached wool shows lower degree of deterioration than that of conventionally bleached wool. The COD and BOD of the wool bleaching effluents were determined.     

45—THE BLEACHING OF CROSSBRED WOOLS: OBSERVATIONS ON THE RELATIONSHIP BETWEEN THE PRICE AND THE COLOUR OF SOME SCOURED NEW ZEALAND CROSSBRED WOOLS

An account is given of an investigation of the relationship between the price and colour of a range of New Zealand scoured wools, consisting of 46/50s fleece types, second-shear, billies and pieces, and dag-wool blends, in connexion with the assessment of the beneficial effect of pad–steam bleaching with sodium or zinc formaldehyde sulphoxylate. The colour of the wools was judged visually and by making reflectance measurements, and the cost of improving the colour by bleaching was related to the expected increase in value of the wool. Only wools of rather poor colour and especially dag-wool blends did not benefit economically from being bleached.     

Optimisation of soya bean oil bleaching by ultrasonic processing and investigate the physico‐chemical properties of bleached soya bean oil

In this study, an ultrasonic bleaching method for soya bean oil under different conditions was optimised by monitoring the reduction of oil‐containing colourants. Ultrasonic power, clay content, temperature and time had a significant interaction effect on (P < 0.05) the reduction of oil pigments and colourants. Under optimised conditions, red and yellow colour indices in the ultrasound‐bleached soya bean oil reduced to 74.44% and 75.55%, and 54.18% and 58.85%, respectively, at amplitudes of 85% and 65%. Carotenoid and chlorophyll concentrations also reduced to 81.19% and 83.62%, and 94.66% and 95.26%, respectively, at 85% and 65% ultrasonic power. The overall contents of sterols and tocopherols decreased using ultrasonic bleaching process compared with the neutralised soya bean oil. Although the peroxide value (PV) of the soya bean oil after ultrasonic and control bleaching reduced, this index was higher in the ultrasonic bleached oil than the control one. The results showed that the ultrasonic bleaching process could be an alternative to the industrial bleaching method as it reduced clay usage, temperature and time of bleaching about 35%, 35% and 10%, respectively.     

碱—蒽醌化学浆漂白性能的研究

对加拿大一枝黄花碱-蒽醌化学浆D／CEpD和D／CEpD1EpD2漂白条件、漂白浆特性和D／CEpD漂白浆的打浆性能进行了研究。确定了较佳的D／CEpD和D／OEpD1EpD2漂白工艺。D／CFpD漂白较佳工艺条件：总用氟量为10％（D／C、D段用氯量比6．5：3．5），Ep段H2O2用量1．0％。漂白浆指标：AP＋AQ浆得率89．61％，卡伯值1．9，白度79．6％ISO，返黄值5．6，粘度718mL／g；KP＋AQ浆得率91．00％，卡伯值1．3，白度82．3％ISO，返黄值4．7，粘度711mL／g。D／CEpD1EpD2漂白较佳工艺条件：总用氟量10％（D／C、D1和D2段用氯量比为6：3：1），EP段H2O2用量1．5％。漂白浆指标为：AP＋AQ浆得率88．11％，卡伯值1．2，白度83．8％ISO，返黄值4．0，粘度710mL／g；KP＋AQ浆得率88．96％，卡伯值1．1，白度84．7％ISO，返黄值3．9，粘度709mL／g。     

In vivo assessment of odour retention in an antimicrobial silver chloride-treated polyester textile

An investigation is described in which the effects of bleaching on the reflectance value and yellowness or colour difference of jute were studied. Different concentrations and pH values of solutions of bleaching powder, sodium hypochlorite, and a combination of bleaching powder and hydrogen peroxide were treated under different conditions. The bleached samples were also reduced with potassium borohydride and sodium hydrosulphite. Bleaching with bleaching powder at a fixed available-chlorine concentration (0.25%) at pH 10.5 for 20 min and then exhausting the bath is shown to work better than four successive treatments of 7.5 min each, followed by antichlor treatments. Even better, however, were samples that had been bleached with a combination of bleaching powder and hydrogen peroxide and subsequently reduced with potassium borohydride. Infra-red spectra showed that carbonyl groups resulting from the peroxide treatment disappeared after reduction with borohydride.