锅炉烟道气饱充上浮新工艺在糖厂的应用

本文介绍2007/08、2008/09年榨季我公司下属双江公司和勐省公司利用锅炉烟道气中进行糖浆和混合汁烟气饱充上浮技术应用及经济效益分析。     

甘蔗糖厂混合汁烟道气饱充上浮工艺探讨

本文在介绍混合汁烟道气饱充上浮澄清技术特点及工艺流程的基础上,结合实践应用进行讨论,分析了混合汁烟道气饱充上浮工艺在甘蔗糖厂应用的可行性及应用前景。     

烟道气饱充上浮技术处理顽性蔗汁工艺

基于烟道气饱充上浮技术处理顽性蔗汁的查定效果,通过单因素和正交试验研究,对浮清汁的澄清工艺进行了优化设计。结果表明,磷酸值对过滤速度、色值的影响最大,对沉降速度、纯度的影响最小;硫熏强度对纯度的影响最大,对过滤速度、色值影响最小;中和pH值对沉降速度、过滤速度有一定程度影响。各因素对还原糖的影响在统计学上不显著(p0.05)。通过评价沉降速度、过滤速度、纯度和色值,分别得到了最优的工艺条件。     

锅炉烟道气CO2饱充澄清混合汁的工艺优化

为了稳定并进一步提高锅炉烟道气CO2饱充混合汁的澄清工艺应用效果,本文通过使用自制饱充设备,进行单因素与正交试验,分析饱充温度、饱充pH值、饱充时间及烟道气CO2浓度等对胶体去除率、清混汁纯度差、清汁色值及钙盐含量的影响,优化混合汁C02饱充工艺。结果表明饱充温度、饱充pH值、饱充时间及烟道气CO2（v／V）浓度对澄清效果有明显影响,饱充温度、饱充pH值及饱充时间均存在一最佳值;CO2浓度越高,澄清效果越理想,当浓度低于12％时对混合汁进行饱充澄清意义不大;最优工艺组合为饱充温度50℃,饱充pH11．0,饱充时间8min,CO2浓度22％。     

利用提浓锅炉烟道气CO_2饱充糖浆的探讨

锅炉烟道气经过除尘和降温后,经过汽水分离器去除游离水,用压缩机升压至0.2M Pa后,再进入吸附塔。变压吸附提纯烟道气中二氧化碳。利用所选择的吸附剂在0.2M Pa吸附操作压力下,选择吸附烟道气中的气态水、二氧化碳等气体,最终将二氧化碳气体纯度富集在20%左右。二氧化碳经水环式真空泵输送至制炼,对粗糖浆进行饱充,取代糖浆硫漂,达到降低糖浆PH值、提高糖浆纯度、降低产品含硫量的目的。     

石灰烟道气净化岩卤工艺的研究

盐随着工业和食用对其要求的提高．卤水净化对于制盐行业势在必行。两碱法和石灰纯碱法虽工艺成熟，但成本太高．不利于提高效益。石灰二氧化碳法净化卤水工艺上还有一些问题值得探讨。本文就利用石灰和锅炉烟道气净化卤水中的钙、镁等净化工艺提出一点设想。     

枸杞熟化产物类黑精大孔吸附树脂的纯化

为研究枸杞熟化产物类黑精分离纯化的效果及对抗氧化性能的影响,采用乙醇溶液提取枸杞熟化产物类黑精后,通过静态吸附解吸实验及动态解吸实验筛选出最佳树脂以及最佳洗脱剂浓度对类黑精进行纯化,测定树脂纯化前后类黑精的抗氧化性。研究表明,6种树脂(D101、D312、X-5、HPD100、AB-8、CAD-40)中AB-8型大孔吸附树脂纯化效果最佳,静态吸附率为70.24%,解析率为88.84%,40%的乙醇溶液洗脱效果最佳,纯化后类黑精的总还原力为1.36,提高了0.524,DPPH自由基清除率达到了96.72%,提高了35.43%,·OH清除率达到65.77%,提高了26.74%。AB-8型树脂可以作为熟化枸杞类黑精的纯化材料,且纯化后类黑精抗氧化性能有明显提高。     

石灰-烟道气法卤水净化工艺碳化反应的试验研究

针对卤水净化中,除去钙镁等主要杂质的工艺,采用了石灰-烟道气法,原料仅使用便宜易得的生石灰和工业锅炉烟道气,不仅大大降低了净化卤水的成本,而且减少了工业废气的排放,保护了环境。实验主要对有效除去钙离子做了深入的研究。     

黑麦芽类黑精体外抗氧化活性的研究

目的:研究黑麦芽中类黑精的抗氧化性,为开发具有保健功能的啤酒及开发新的天然抗氧化剂提供科学依据。方法:从黑麦芽中提取出类黑精(MBM),测定了MBM的还原力、MBM对[DPPH.]自由基的清除率以及对小鼠肝脏脂质过氧化产生MDA的抑制率。结果:MBM的还原力EC50(吸光值达0.5时所需的样品有效质量浓度)为31.691μg/mL;MBM对[DPPH.]自由基的清除能力IC50([DPPH.]自由基清除率为50%时所需的样品有效质量浓度)为148.3236μg/mL;对小鼠肝匀浆脂质过氧化产生MDA的抑制能力IC50(MDA抑制率为50%时所需的样品有效质量浓度)为38.0518μg/mL。结论:黑麦芽类黑精具有较强的抗氧化性,具有开发保健型啤酒,开发天然抗氧化剂的潜力。     

黑蒜类黑精的超声提取工艺优化及其稳定性和抗氧化性研究

以黑蒜为原料,采用超声法提取黑蒜中的类黑精,并对提取工艺条件进行优化。选取乙醇体积分数、料液比、超声时间和超声温度四个影响因素进行单因素实验,在此基础上,采用正交试验优化最佳提取工艺,同时对黑蒜类黑精的稳定性和抗氧化活性进行研究。结果表明,超声法提取黑蒜类黑精的最佳工艺参数为:乙醇体积分数为10%、料液比为1:7、超声时间为40 min、超声温度为70℃,此条件下得率为3.465%。稳定性研究结果表明,温度高于50℃时,类黑精稳定性不好,而-15℃冷冻和4℃冷藏条件下,类黑精呈现较好的稳定性。氧化剂H₂O₂和还原剂Na₂SO₃、甜味剂、暗光对黑蒜类黑精稳定性无显著影响,直射光、酸味剂、强酸pH2～4和弱碱pH8～10,则会使其稳定性降低,而金属离子Zn²⁺和Fe²⁺会与其发生络合反应。质量分数小于2%时的山梨酸钾和苯甲酸钠会降低类黑精的稳定性,而0.05%的苯甲酸钠和0.1%的山梨酸钾对类黑精稳定性影响很小,可作为类黑精食品的防腐剂。黑蒜类黑精的DPPH·...     

原糖溶液电解脱色的研究

阐述了原糖溶液电解脱色过程的机理,并对电解原糖浆脱色进行了实验研究,考察电解时间、电流密度、温度、锤度等因素对原糖浆脱色的影响。结果表明,电解对原糖溶液具有显著的脱色效果,对40築x的原糖溶液脱色率可以达到90%以上。     

Evaluation of CIE-lab colour parameters during the clarification of a sugar syrup from Mesquite pods (Prosopis Pallida L.)

Summary There are several commercial sugar syrups obtained from the Mesquite pods, however their dark-brown colour limits their use in the food industry. In this work we clarified sugar syrups from Mesquite pods by a two-step procedure: (1) lime-milk treatment with the addition of different amounts of calcium hydroxide and aluminium sulphate, and (2) ion-exchange treatment using A-400 anionic and/or C-100 cationic resins. Samples were evaluated for colour using the Hunter Lab colorimeter (Hunter Associates Laboratory Inc, Reston, VA, USA) (L*, a*, b*, ) and for sensory acceptability during the clarification process. The results showed that with the addition of 7.5% calcium hydroxide and 8.0% aluminium sulphate, followed by treatment with the anionic resin A-400, a syrup with a high degree of purity (92.3%) and a lighter-brown colour than other commercial samples could be obtained. The colour values, as measured by the Hunter meter were; a lightness of L* = 6.17 and a yellow colour of 0.74 expressed as a a/b* ratio. A negative correlation was obtained between the total polyphenol content (TP) in the sugar extract and the lightness values (L*); L* = 15.50–0.00511 TP (mg kg^–1). The A-400 resin retained the greatest amount of polyphenols (92.9%). CIE-Lab parameters are proposed as a good means for objective colour comparison with other studies on the clarification of sugar syrups.     

Assessment of variables effects on sugar cane juice clarification by carbonation process

This paper reports a study of sugar cane juice carbonation and the evaluation of variables effects such as pH, carbonation time and temperature on industrially relevant parameters for the quality of sugar cane juice. Three different batches of sugar cane juice were evaluated using a complete two‐level factorial design with central point performed in triplicate. From results in this work, it can be seen that the higher sucrose concentrations and lower percentage of total soluble solids and reducing sugars were obtained in clarified juices with the maximum values for pH, time and reaction temperature (9.5, 60 min and 80 °C). The temperature favoured the removal of starch, phosphate and turbidity. Colour removal reached a maximum of 88–93% among the batches. The optimum clarification condition using carbonation procedure can be achieved between 20 and 40 min, at pH values between 8.0 and 9.5 and temperature condition at 80 °C.     

木薯淀粉与玉米淀粉用于生产淀粉糖浆的对比研究

根据淀粉糖的生产工艺,对比研究木薯淀粉及玉米淀粉对淀粉糖浆质量及生产成本的影响。试验结果表明,玉米淀粉作为生产淀粉糖浆的原料效果较好。     

燃煤锅炉烟气氨法脱硝实时监测系统

为监测火电厂锅炉烟气氨法脱硝过程中的氨气泄漏情况,利用GSM,Internet和ZigBee等多种技术,设计了一个集采集、报警、查询为一体的监测系统,实现了用无线传感器网络对氨法脱硝系统运行环境进行分布式液氨泄漏监测.该系统能有效提高氨法脱硝现场的安全性,具有低功耗、低单位成本和组网灵活等优点.     

Effect of pH on non-enzymatic browning reaction during γ-irradiation processing using sugar and sugar–glycine solutions

Effects of pH on the non-enzymatic browning reaction caused by γ-irradiation processing were investigated. The brown colour development of irradiated sugar–glycine solutions was greater in a buffer system than in deionized distilled water (DDW) with higher pH. Although browning of irradiated sugar solution without glycine was highly increased was in alkaline buffer, no browning was developed in DDW. The maximum browning of the solutions of sugar and sugar–glycine were observed at pH 10 and pH 8, respectively. The browning intensity was in the following order: sucrose ? fructose > glucose. Non-constant pH was observed in DDW (dropped pH between 1.58 and 2.03 units); however, the use of buffers was partially effective in keeping pH constant (pH dropped between 0.03 and 0.56 units). When the irradiated solutions of sugar with and without glycine were analyzed using reverse phase high performance liquid chromatography with diode-array detection (HPLC-DAD), three peaks were separated at 3.37 ± 0.04, 4.60 ± 0.02, and 2.53 ± 0.26 min, and the λ_max values of these peaks were the range 259–288 nm. The sum of the areas of these peaks at 260 nm increased with increasing pH. The results of this study indicated that conditions of the system, such as pH and media, can influence the non-enzymatic browning reaction during γ-irradiation.     

Elman网络近红外光谱技术同时测定鲜乳中三种主成分含量

采用Elman神经网络(反馈神经网络,Recurrent Network)结合近红外光谱技术建立鲜乳中的脂肪、蛋白质、乳糖定量分析模型.用偏最小二乘法(Partial Least SqHales.PUS)将原始数据压缩主成分,取前3个主成分的14个吸收峰值输入Elman网络,网络中间层神经元个数为53.Elman网络模型对样品中3个组分含量的预测决定系数(R2)分别为:0.985、0.951、0.967,表明所建Elman网络预测模型能够较准确预测鲜乳中脂肪、蛋白质和乳糖的含量,从而为近红外光谱的多组分定量分析提供了新思路.     

用混合线性分析法建立苹果糖度近红外光谱预测模型

用混合线性分析法的一种变形算法建立了苹果糖度近红外光谱预测模型，并与偏最小二乘模型进行比较。结果表明：虽然最佳的混合线性分析法模型（18个主因子）比最佳偏最小二乘模型（11个主因子）复杂．但其精度却明显优于偏最小二乘模型：利用梗正集的28个苹果样本建立的糖度混合线性分析法校正模型，其相关系数r^2和标准偏差SEC分别为0．92509和0．40618；该校正模型经预测集的11个样本验证，相关系数r^2和标准偏差SEP分别达到0.87611和0．48480。混合线性分析法建立的糖度模型对苹果光谱的校正标准偏差SEC和预测标准偏差SEP分别比PLS法的SEC（0．41473）和SEP（0．50473）减小了2％和3．9％。结果表明：在诸如苹果糖度这一类农产品品质综合指标（非纯组分含量指标）的光谱检测中，应用混合线性分析法进行定量分析是完全可行的。并且其结果可与偏最小二乘法（PLS）的结果相媲美。     

镉超标大米水解糖发酵生产2-酮基葡萄糖酸过程中镉的迁移规律

目的 揭示以镉超标大米为原料发酵生产2-酮基葡萄糖酸过程中镉的迁移规律,并获得符合食品抗氧化剂D-异抗坏血酸钠合成要求的2-酮基葡萄糖酸。方法 以正常大米、镉超标大米和混合大米为原料,系统分析大米糖化、种子培养、2-酮基葡萄糖酸发酵、发酵产物提取等过程中镉的含量和分布,确定镉的迁移规律及其对2-酮基葡萄糖酸发酵性能和D-异抗坏血酸钠产品品质的影响。结果 大米原料和辅料碳酸钙中的镉的含量对2-酮基葡萄糖酸发酵性能影响不显著;发酵产物的提取过程有效降低了2-酮基葡萄糖酸中的镉含量,提取过程中产生的酸化废渣（主要由硫酸钙和菌体组成）可富集90%以上的镉;以镉超标大米为原料制备的D-异抗坏血酸钠的质量符合国家标准要求,未检出镉的存在。结论 该研究为综合利用镉超标大米生产2-酮基葡萄糖酸、进而生产高附加值的食品添加剂D-异抗坏血酸钠提供了理论依据和技术支撑。     

Understanding the impact of crop and food production on the water environment—using sugar as a model

The availability of fresh water and the quality of aquatic ecosystems are important global concerns, and agriculture plays a major role. Consumers and manufacturers are increasingly sensitive to sustainability issues related to processed food products and drinks. The present study examines the production of sugar from the growing cycle through to processing to the factory gate, and identifies the potential impacts on water scarcity and quality and the ways in which the impact of water use can be minimised. We have reviewed the production phases and processing steps, and how calculations of water use can be complicated, or in some cases how assessments can be relatively straightforward. Finally, we outline several ways that growers and sugar processors are improving the efficiency of water use and reducing environmental impact, and where further advances can be made. This provides a template for the assessment of other crops. © 2013 Society of Chemical Industry