超声波协同草酸铵法提取香蕉皮中果胶的研究

该文研究采用超声波辅助草酸铵法提取香蕉皮中果胶的最佳工艺条件,研究了不同草酸铵浓度、料液比、超声功率、超声时间、超声温度和浸提时间对果胶提取率的影响。通过正交试验确定提取香蕉皮果胶的最优工艺条件为:草酸铵浓度0.8%,超声温度65℃,料液比35︰1,超声时间65 min,此条件下香蕉皮果胶的提取率为23.27%。     

草酸铵法提取冬瓜皮果胶及其理化性质研究

以冬瓜皮为原料,采用草酸铵法提取冬瓜皮果胶。通过单因素试验和正交试验确定提取冬瓜皮果胶的最优工艺条件,并对提取的果胶成品进行理化指标测定。结果表明:在试验范围内,草酸铵质量浓度、提取温度、提取时间和料液比对冬瓜皮果胶的提取得率均有一定的影响,其最佳工艺条件为草酸铵质量浓度1.5%、温度为80℃、提取时间2.0 h、料液比为1∶30(g/m L);在该工艺条件下果胶提取率达8.91%。该方法提取的果胶各项指标均达到了国家标准GB 25533-2010《食品添加剂果胶》和行业标准QB 2484-2000《食品添加剂果胶》要求。     

响应面法优化超声辅助提取豆腐柴多酚的工艺

为确定豆腐柴多酚的最佳提取工艺条件,在单因素试验基础上,采用三因素三水平的响应面试验优化设计方法,研究乙醇体积分数、超声温度、提取时间对多酚提取率的影响,得到最佳提取工艺条件为液料比40 m L/g、乙醇体积分数52%、超声温度74℃、提取时间33 min,在此条件下豆腐柴多酚提取率为(42.43±1.38)mg/g。     

菠萝皮渣果胶超声波提取工艺条件研究

目的:探讨采用草酸铵作为提取溶剂和超声波振荡处理法提取菠萝皮渣果胶的工艺条件。方法:以果胶提取率作为测定指标,通过正交实验,确定了菠萝皮渣果胶最佳提取工艺条件。结果:最佳组合为草酸铵浓度0.4﹪、料液比1∶40、pH5.0、温度70℃、超声波频率47kHz、提取时间90min,菠萝皮渣中的果胶提取率达到90%。     

超声辅助草酸铵法提取南瓜果胶及其理化性质研究

以籽用南瓜废弃果肉为原料,将超声法的"空化"作用与草酸铵法的"螯合"作用相结合,优化提取果胶工艺。通过单因素试验确定了各影响因子(草酸铵浓度、料液比、提取时间和提取温度)的数据范围,并揭示了正交试验最优条件下果胶的理化特性。结果表明,各因素对提取率有不同程度的作用,提取温度80℃,草酸铵浓度0.8%,料液比1∶30,提取时间60 min,果胶平均得率为6.09%。该方法提取的果胶具有GB 25533-2010中的果胶凝胶特征,与QB 2484-2000标准和《食品化学法典》的要求一致,酯化度为75.23,属高甲氧基果胶。     

菠萝蜜丝果胶提取工艺优化

采用酸提取方法对菠萝蜜丝果胶的提取工艺条件进行研究,考察乙醇浓度、沉淀时间、提取温度、提取液pH、液料比、提取时间等因素对果胶提取率的影响。确定了酸提取菠萝蜜丝果胶的最佳工艺条件:乙醇浓度为70%、沉淀时间为50 min、提取液pH为2.5、提取温度为95℃、提取时间90 min、液料比为20∶1(mL/g)。在最佳提取工艺条件下,菠萝蜜丝中果胶的提取率为2.12%。     

响应面法优化超声波辅助提取沃柑皮中果胶工艺研究

以沃柑皮为原料,采用超声波辅助乙醇提取沃柑皮中果胶,通过单因素试验考察了液料比、提取液pH、超声时间和提取温度对提取率的影响,以沃柑皮中果胶提取率为最终指标,同时采用响应面试验设计优化了提取工艺条件.结果表明:沃柑皮中果胶提取最佳工艺条件为:液料比33:1(mL/g)、提取液pH为2.5、超声时间69min、提取温度6...     

超声波辅助提取佛手废渣中果胶的工艺研究

探讨了超声波辅助提取佛手废渣中果胶的工艺条件.通过考察料液比、浸提pH值、浸提温度和超声浸提时间4因素对果胶提取率的影响,并在单因素的基础上设计了正交试验,确定了果胶提取的最佳工艺条件.正交试验优化后的最佳提取工艺条件为料液比1∶50g/mL,浸提pH值1.0,浸提温度90℃,超声时间90min,在此工艺条件下,果胶的提取率达到18.42%.利用超声波辅助提取可以有效缩短提取时间,具有成本低、效率高、工艺简单和环境污染小等优点,对佛手废渣的综合利用具有一定的参考价值.     

响应面试验优化超声耦合双水相体系提取茶多酚工艺

采用超声耦合乙醇-硫酸铵组成的双水相体系提取茶多酚,以乙醇体积分数、硫酸铵质量浓度、液料比、超声时间、超声温度为影响因素,以茶多酚提取率为响应值,通过响应面分析法得出最佳提取工艺条件为乙醇体积分数50%、硫酸铵质量浓度0.25 g/mL、液料比70∶1（mL/g）、超声时间16 min、超声温度45 ℃,此时茶多酚提取率可达17.58%。     

正交法优化超声波提取橘皮果胶的工艺研究

将超声波与酸法结合探究橘皮果胶得率.设置4个影响试验结果的因素:料液比、pH、超声温度、超声时间,每个因素选取5个水平进行单因素试验,通过正交试验优化工艺.结果 表明,最佳提取条件为:料液比1∶15 (g/mL)、pH 1.5、超声温度70℃、超声时间40 min,根据最优方案获得的果胶提取率为22.43％.     

响应面法优化磨盘柿果胶的提取工艺

为了充分开发磨盘柿资源,以磨盘柿加工柿子酒后的废弃物-柿子渣为原料,对果胶的提取工艺进行了研究。采用草酸铵提取法对柿子渣的果胶进行提取,单因素实验考察了提取时间、提取温度、提取液pH、料液比、草酸铵浓度对提取率的影响,并利用响应面分析法对果胶的提取工艺进行了优化。结果表明,最佳的提取条件为:草酸铵浓度为0.60%,提取温度95℃,反应时间4 h,pH1.9,在此条件下果胶的提取率为11.2%±0.3%。通过此方法,能够有效地提取出果渣中的果胶,为磨盘柿子的综合开发提供了思路。     

重庆奉节脐橙果皮中果胶提取工艺优化研究

以重庆奉节脐橙为原料,通过对料水比、浸提液pH、浸提温度、浸提时间、草酸铵浓度进行单因素试验,采用正交试验法对重庆奉节脐橙皮果胶提取工艺条件进行优化,并对提取的果胶制品的性质进行检测,包括总半乳糖醛酸含量、酯化度、含水量(干燥失重)、总灰分量、盐酸不溶物、pH等。试验结果表明,重庆奉节脐橙皮中果胶提取的最佳工艺条件为:浸提液pH 1.8,提取温度80℃,提取时间为120 min,草酸铵浓度为0.2%,果胶得率有25.14%。经理化检验,果胶制品的总半乳糖醛酸含量为66.3%,酯化度为63.72%,水分含量为8.15%,总灰分4.78%,盐酸不溶物0.86%,pH 2.33。该试验方法获得的果胶提取得率高,品质基本符合国家标准。     

再造烟叶原料烟梗中果胶的去除

为减少果胶对再造烟叶吸味的不利影响,改善其内在品质,以除糖后的硫酸咔唑果胶分析方法为定量基础,考察了水、EDTA溶液、六偏聚磷酸钠溶液、磷酸氢二铵溶液、草酸铵溶液等提取助剂对烟梗中果胶的去除效果,并结合生产工艺和节约能耗的因素,建立二次作差响应曲面实验分析方法,优化烟梗果胶浸提条件,得到最佳工艺条件为:1.20％草酸铵溶液,液料比为10∶1,提取温度为60℃,时间为30 min.     

苎麻果胶的提取及在果胶酶活测定中的应用

研究了苎麻中纤维果胶的提取,优化的提取工艺为:温度90℃,草酸铵质量浓度5g/L,液料比为30:1,反应时间90min。以纤维果胶和苹果果胶为底物,采用DNS法测定了棉精练用碱性果胶酶的酶活力。结果表明,以纤维果胶为底物测定的棉织物精练用碱性果胶酶酶活力为151.6U/mL,远高于苹果果胶的5.3U/mL,更适合用来表征棉织物精练用果胶酶的酶活力。     

Physicochemical properties of pectins from ambarella peels (Spondias cytherea) obtained using different extraction conditions

Extraction and use of pectins from ambarella peels could add value to the waste products arising from processing of the fruit. Dried alcohol-insoluble residues (AIR) of ambarella peels were treated separately with HCl, deionised water and oxalic acid/ammonium oxalate solutions, and the resulting pectin extracts analysed for some biochemical and physicochemical parameters. The results show that pectin yield (9–30% dry AIR), uronic acid (557–727 mg/g dry weight), neutral sugars (125–158 mg/g), degree of methylation (50–58%) and acetylation (4–6%), molar mass (263,000–303,000 g/mol) and intrinsic viscosity (179–480 ml/g) varied significantly (p < 0.05) with the various extraction methods used. Extraction with oxalic acid/ammonium oxalate solution gave the highest pectin yield, with high molar mass and degree of methylation, making the extracts suitable for use as additives in the food industry. The results compared well to lime pectin extracted under the same conditions, indicating their commercial significance.     

Pectic substances in onion and garlic skins

Pectic substances from onion (white and red varieties) and garlic skins were isolated by extraction with ammonium oxalate. White onion and garlic skins were found to contain 11 to 12% pectin which can be recovered as a by-product in the dehydration industries. Characterisation of these pectic substances in terms of jelly grade, molecular weight, degree of esterification, methoxyl and uronide content was attempted. Pectins from white onions were superior to red onions in terms of jelly grade. Both types of onion pectins appeared to be of the rapid set type while the garlic skin pectin was of the medium set variety. Equivalent weight, methoxyl content and degree of esterification by themselves did not give any clear indication of pectin grade. Intrinsic viscosity values gave good correlation between jelly grade and molecular weight. The pectic substances from garlic skin differed from onion skin in certain respects and most remarkably in its viscosity behaviour.     

大豆皮果胶不同提取方法的研究

为比较不同提取方法对大豆皮果胶提取得率和产品性质方面的影响,以大豆皮为原料,分别采用水浴盐酸提取法、水浴草酸铵提取法和高压蒸汽草酸铵提取法从大豆皮中提取果胶,所得果胶提取液经乙醇沉析法得到果胶。分析比较了三种提取方法提取的果胶:提取得率、色泽、纯度、FTIR和蛋白质等指标,结果发现,草酸铵提取的果胶在色泽、纯度上优于盐酸提取的果胶,高压蒸汽加热方法能将提取时间缩短至20min。三种提取方法得到的果胶经过鉴别实验和FTIR分析都有明显的果胶特征,但果胶产品的纯度偏低,其中杂质主要是蛋白质。产品的水分和灰分含量都符合国家标准,但是其中的蛋白质含量都较高,有待进一步纯化。     

Isolation and characterisation of pectic substances from murta (Ugni molinae Turcz) fruits

Cell walls polysaccharides from murta fruit (Ugni molinae Turcz), an endemic Chilean species with relevant food uses, were fractionated by water, ammonium oxalate, hot diluted HCl and cold diluted NaOH extractions. The polysaccharide fractions were analysed for monosaccharide composition and physicochemical properties. Pectic substances were found in all extracts, but mainly in the oxalate and acid soluble fractions, in which they appear as homogalacturonan polymers. Murta pectin was further extracted by hot diluted acid treatment using industrial conditions, yielding 30% by weight of dry fruit. The polymer showed similar composition and physicochemical properties to those of commercial citrus pectin, presenting a galacturonic acid content of 70.9% (w/w), a molecular weight of 597 kDa, and a methoxylation degree of 57%. The FT-IR spectrum of murta pectin suggests the presence of ferulic acid residues on its structure and the NMR analysis confirmed the structure of this polysaccharide. It is concluded that murta fruit can be considered as a valuable source of high quality pectin.     

酶法制备豆皮低聚木糖的工艺研究

利用木聚糖酶酶解豆皮制备低聚木糖,通过单因素试验考察酶解温度、pH 值、时间、料液比以及酶添加量对酶解液中低聚木糖含量的影响,并在此基础上通过正交试验确立最佳酶解工艺条件：酶添加量0.3%、pH4.3、料液比1:15(g/mL)、温度40℃、酶解时间2h。该最佳工艺条件下,总还原还原糖含量为5.74mg/mL。通过离子色谱检测酶解液中的糖分组成,发现酶解液中的单糖以木糖为主,相对含量达到54.99%。     

Changes in Pectic Substances and Enzymes during Ripening and Storage of "Keitt" Mangos

The relationship of the distribution of pectic substances to tissue softening was examined in ripening mangos at four stages of ripeness. Water-soluble and alkali-soluble pectin declined and ammonium oxalate soluble pectin increased as the mango lost its firmness and became soft. Polygalacturonase and cellulase activities of cell wall preparations increased markedly during ripening. The decline in alkali-soluble pectin and the increase in polygalacturonase activity correlated well with the loss of firmness. Alkali-soluble pectin declined slowly in ripe mangos stored at 4°C. This decline correlated with loss of firmness of the stored mangos. The cellulase activity of cell wall preparations from ripe mangos increased during 4°C storage and the increase correlated with the decrease in firmness.