南瓜果胶酸解提取技术

开展南瓜果胶酸法提取技术的研究,针对影响南瓜果胶得率的因素进行单因素试验,并在此基础上开展正交试验的研究,结果表明,南瓜果胶提取最佳工艺条件为pH1.5,时间1.5h,物料粒度0.2mm,料液比1∶35(g/mL).经分析,南瓜果胶的酯化度为55.73%,属于高酯果胶.     

超声波联合果胶酸酶提取柚皮果胶的工艺研究

采用超声波对柚皮进行处理,然后加入复合酶提取果胶,可减少无机酸对环境的污染.红外光谱分析表明果胶中含有较多的糖类物质,不合蛋白.在单因素实验的基础上采用正交实验对实验结果进行优化,在超声波功率240W、超声频率24kHz、超声波处理时间20min、单次提取时间50min、缓冲液pH5.5、酶提取温度55℃、酶液用量0.9％的条件下,柚皮果胶的平均提取量为236.2mg/g,远高于相同工艺条件下常规水浴法提取的果胶提取量.     

超声波联合果胶酸酶提取柚皮果胶的工艺研究

采用超声波对柚皮进行处理,然后加入复合酶提取果胶,可减少无机酸对环境的污染。红外光谱分析表明果胶中含有较多的糖类物质,不含蛋白。在单因素实验的基础上采用正交实验对实验结果进行优化,在超声波功率240W、超声频率24kHz、超声波处理时间20min、单次提取时间50min、缓冲液pH5.5、酶提取温度55℃、酶液用量0.9%的条件下,柚皮果胶的平均提取量为236.2mg/g,远高于相同工艺条件下常规水浴法提取的果胶提取量。      

超滤浓缩制备南瓜果胶的工艺研究

采用超滤浓缩后乙醇沉淀的方法制备南瓜果胶.通过单因素试验,确定优化超滤条件为:超滤膜截留分子量50 kD,压力0.08 MPa,温度25 ℃,溶液pH 7.0;在该条件下,将南瓜果胶提取液浓缩至原体积1/5,再加入80%乙醇溶液沉淀果胶并洗涤果胶1次,所得的南瓜果胶纯度为80.08%,得率为8.50%,凝胶度为120.25,酯化度为31.82,干燥失重为4.26%,总灰分为3.22%,半乳糖醛酸为88.10%,pH为2.7,铅及砷含量分别为1.2 mg/kg和0.036 mg/kg,各项指标均达到国家质量标准QB 2484--2000.     

微波法提取南瓜果胶

实验旨在探讨用微波法提取南瓜中果胶的最优方案,选取PH值、料液比、辐射时间、浸提温度4个因素做正交实验,得出最佳条件为:PH=2.0、料液比1:35、辐射时间6min、浸提温度95℃。另外对所提南瓜果胶做了初步品质鉴定。     

膜技术分离纯化南瓜果胶的工艺研究

利用提取糖分后的南瓜渣进行果胶的提取,采用膜分离技术改进传统工艺,对南瓜提取液进行除杂浓缩,再经过醇沉精制,最后通过真空干燥得到果胶产品。试验结果显示,经过膜除杂和浓缩后的果胶溶液,不仅能减少后续乙醇的使用量,而且还能提高果胶的纯度。因而采用此工艺可降低成本,提高经济效益。     

南瓜果胶脱色树脂的比较研究

本试验运用树脂对南瓜果胶水解液进行脱色,并比较了几种树脂的脱色效果并确定了最佳脱色条件,结果为阴离子树脂(201×7)×D900树脂在20℃,摆幅为7r/min,脱色14h脱色效果最佳.     

南瓜粉中果胶的提取工艺

从脱色后的南瓜粉中提取果胶 ,利用乙醇进行沉淀。就提取工艺参数对果胶的得率和胶凝度进行了研究。利用正交实验 ,确定了果胶提取的最优工艺条件     

南瓜果胶脱色工艺的研究

将南瓜皮中提取的果胶分别用活性炭、双氧水及树脂进行脱色研究。实验结果表明,树脂201×7采用摆幅为5r/min,在经过15h振荡后效果最佳。     

南瓜果胶脱色工艺的研究

将南瓜皮中提取的果胶分别用活性炭、双氧水及树脂进行脱色研究。实验结果表明,树脂201×7采用摆幅为5r/min,在经过15h振荡后效果最佳。      

树脂在南瓜果胶脱色中的应用

运用树脂对南瓜果胶水解液进行脱色,比较了几种树脂的脱色效果并确定了最佳脱色条件,结果为阴离子树脂(201×7)×D900两种树脂在20℃、摆幅为7、脱色12h脱色效果最佳。     

Emulsifying and structural properties of pectin enzymatically extracted from pumpkin

The present study investigated the emulsifying and structural properties of pectin enzymatically extracted from pumpkin. Pumpkin pectin fraction A was obtained from raw pumpkin with an enzymatic preparation of cellulase and α-amylase. Pumpkin pectin fraction B was achieved by treating the fraction A solution with pronase to reduce protein content. According to the findings (on protein content, galacturonic acid content, neutral sugar composition, and molecular weight distribution), the pronase treatment could remove protein from the fraction A without considerably influencing any other chemical and molecular properties. Moreover, the fraction A exhibited emulsifying properties in water and oil mixture, whereas the removal of protein in the fraction B resulted in the loss of emulsifying properties. The FT-IR and 1D NMR analysis revealed that the backbone of pumpkin pectin is mainly composed of α-1,4-d-galacturonic acid in which a considerable portion of galacturonic acid residues is present as methyl esters, and some l-rhamnose are involved in the linear region of the backbone through α-1,2-linkages.     

树脂在南瓜果胶脱色中的应用

运用树脂对南瓜果胶水解液进行脱色,比较了几种树脂的脱色效果并确定了最佳脱色条件,结果为阴离子树脂(201×7)、D900两种树脂在20℃、摆幅为7、脱色12h脱色效果最佳。     

酶解冷榨法制取南瓜籽油的工艺研究

以南瓜籽为原料,通过先冷榨,冷榨饼再经酶解后复榨制取南瓜籽油。以出油效率为指标,通过单因素实验确定的最佳酶解条件为酶解温度50℃、酶解p H 7.0、酶用量2.0%、酶解时间4.5 h。在最佳酶解条件下进行酶解,出油效率达72.6%。以亚油酸含量为响应值,通过响应面优化确定的复榨过程最佳工艺参数为物料含水量7.0%、榨膛温度76℃、榨膛压力3.5 MPa,在最佳工艺参数下得到的南瓜籽油中亚油酸含量为38.02%。     

球磨辅助酶解制备南瓜籽ACE抑制肽

以南瓜籽蛋白为原料,通过球磨预处理辅助酶解法制备血管紧张素转换酶（ACE）抑制肽。以ACE抑制率和水解度为评价指标,对蛋白酶进行筛选。采用单因素试验研究球磨时间、酶解时间、底物质量浓度、pH和酶解温度对酶解产物ACE抑制率和水解度的影响,在此基础上,以ACE抑制率为考察指标,采用响应面法对球磨辅助酶解工艺条件进行优化。结果表明：球磨预处理可显著提高南瓜籽蛋白的酶解效率;最佳球磨辅助酶解工艺条件为选用碱性蛋白酶、球磨时间6 min、酶解时间10 h、底物质量浓度0.08 g/mL、pH 8.5、酶解温度55 ℃,在此条件下所得ACE抑制肽的ACE抑制率可达(86.65±0.55)%。     

三氯乙酸-酶法脱玉米须多糖中蛋白质工艺的优化

通过比较氯化钙法、盐酸法、三氯乙酸法、Sevag和酶法联用法、三氯乙酸和酶法联用法等5种方法对玉米须多糖进行脱蛋白纯化实验,以蛋白脱除率和多糖保留率及综合评分为指标,探寻玉米须多糖最佳脱蛋白质方法。结果三氯乙酸和酶联用法最佳条件为酶底比2.5(mg/L)、温度50℃、水解时间1 h、TCA浓度为25%、样液体积比为4∶1、静置时间为40 min,多糖的纯度由13.2%提高到24.2%,蛋白脱除率为60.1%,多糖保留率为87.5%。此工艺条件简便有效,适用于玉米须多糖中蛋白质的脱除。     

Effect of pectin oligosaccharide on quality control of quick-frozen pumpkin puree

In this work, pectin oligosaccharide (POS) was prepared by an enzymatic method and was used to protect pumpkin puree during frozen storage. The changes in structure and properties of the pumpkin puree during frozen storage were investigated. The results showed that the addition of POS can minimise changes in syneresis rate, total soluble solids, particle size and zeta potential of pumpkin puree during frozen storage. The results of Scanning Electron Microscope (SEM) and Atomic Force Microscope (AFM) showed that the addition of POS significantly decreased the cavities produced by sublimation of ice crystals and enhanced the continuity of the internal structure of pumpkin puree. Confocal Laser Scanning Microscope (CLSM) results showed that the macromolecules in the quick-frozen pumpkin puree tended to be uniformly distributed during frozen storage with POS added compared with the control sample. In addition, texture was well protected, which allowed the pumpkin puree to maintain a good taste. POS was shown to serve as an antifreeze agent to protect the internal structure of the pumpkin puree during freezing. The optimum concentration to achieve the best anti-freeze effect was 2% POS, which is similar with that of 2% trehalose.