柠檬果渣果胶提取工艺研究

研究以柠檬果渣为主要原料提取果胶的最佳工艺条件,采用微波辅助酸法提取柠檬果胶。通过单因素试验研究萃取剂、微波加热时间、加热功率、pH及料液比对果胶提取率的影响。再通过正交试验进一步优化提取条件,得出影响果胶提取率的因素的主次顺序为微波加热时间＞pH＞微波加热功率＞料液比。最终确定了提取果胶的最佳工艺为选用盐酸溶液作为萃取剂,微波加热时间2 min,pH值为2.0,微波加热功率480 W,料液比1∶30（g∶mL）,其提取率为27.96%。     

柑桔属柠檬类果实果胶酯酶的活性分析

果胶酯酶（PE或PME）能催化果胶脱酯生成低酯果胶和果胶酸,属于一类果胶酶,广泛应用于食品特别是果品加工工业中。以新鲜柠檬为原料,采用NaCl-冷冻离心-盐析的方法提取柠檬果实中的果胶酯酶,pH-stat法对果胶酯酶进行活性分析。研究温度、pH、相对储藏度等因素对柠檬类果实果胶酯酶的活性影响,并探索该酶的最适温度、最适pH值,进而研究该酶的热稳定性;对柠檬果实中果胶含量进行测定。实验表明：58℃,pH=6.90时柠檬中的果胶酯酶的活力最高。     

基于脂肪替代品的柠檬果胶凝胶特性

为提高柠檬皮渣的经济效益,拓宽柠檬高酯果胶在脂肪替代品中的应用,该文针对果胶凝胶作为固态脂肪替代品的相关要求,探讨柠檬高酯果胶的凝胶特性。以柠檬皮渣为原料采用超声辅助柠檬酸法提取果胶,考察柠檬果胶凝胶质构的影响因素,并在质构结果基础上进一步分析果胶质量分数对凝胶流变学特性及持水性能的影响。结果表明,所制备的柠檬果胶为高酯果胶,影响其凝胶质构特性的主要因素有果胶质量分数、蔗糖质量分数和pH值。当果胶质量分数为1.8%、蔗糖质量分数为68%、pH 值为2.7 时果胶凝胶具有最好的质构特性、流变性及持水性,此时果胶凝胶结构最为稳定,综合性能最优。     

柠檬绿茶酸奶的加工工艺研究

目的确定柠檬绿茶酸奶的最佳工艺条件。方法以柠檬汁、绿茶粉和全脂奶粉为主要原料,以保加利亚乳杆菌和嗜热链球菌(1:1)为发酵剂,对柠檬绿茶酸奶的工艺进行初步研究。通过正交试验和感官评定,确定该产品的最佳工艺条件。结果柠檬绿茶酸奶的最佳工艺条件为:柠檬汁和绿茶粉添加体积比例为1:3、柠檬绿茶汁添加量为3%、发酵剂添加量为2%、蔗糖添加量为4%、发酵温度为42℃、发酵时间为4 h。结论该加工工艺简单,操作灵活,制备的柠檬绿茶酸奶产品香甜适口,组织均匀,口感稠厚。     

柠檬红茶酸奶的加工工艺研究

以柠檬、红茶和鲜奶为主要原料,以嗜热性链球菌和保加利亚乳杆菌为发酵剂,经发酵制成一种新型固体酸奶。通过正交试验方法和感官评定,确定该产品的最佳配方和生产工艺为：柠檬红茶汁5%,蔗糖和蜂蜜4%,保加利亚乳杆菌和嗜热性链球菌3％,发酵温度42℃、发酵时间5h。     

柠檬红茶酸奶的加工工艺

以柠檬、红茶和鲜奶为主要原料,以嗜热性链球菌和保加利亚杆菌为发酵剂,经发酵制成一种新型固体酸奶。通过采用正交实验方法和感官评定,确定该产品的最佳生产配方:柠檬红茶汁5%,蔗糖和蜂蜜4%,保加利亚杆菌和嗜热性链球菌3%(均为质量分数,下同),发酵温度42℃,发酵时间5 h。     

利用微波辅助技术提高柠檬皮果胶提取率的研究

通过对微波辅助技术提高柠檬皮果胶提取率影响的研究，探索了微波处理的最佳工艺参数，即微波输出功率600W，料液比1：3，处理时间58s，处理次数3次，果胶得率与未经处理的样品相比，平均增长率为118.31％。     

干燥方法对柠檬果胶理化性质影响

为探究不同干燥方法对柠檬果胶理化性质的影响,实验以柠檬干渣为原料制备果胶,固定提取和浓缩条件,采用热风干燥、真空干燥、冷冻干燥及喷雾干燥等干燥方法对柠檬果胶进行干燥处理,研究不同干燥方法对柠檬果胶得率、半乳糖醛酸、酯化度、能耗、复水比、凝胶强度及果胶结构的影响,采用变异系数法对各指标加权评分,确定柠檬果胶最佳干燥方法。结果表明:所有干燥后的果胶半乳糖醛酸含量均达到国标65%的要求;酯化度均大于50%,傅立叶红外光谱(Fourier Transform Infrared Spectrometry,FTIR)显示,不同干燥方法干燥后的果胶均具有果胶的特征官能团,说明所用干燥方法不会对果胶结构产生影响。不同干燥方法干燥后的果胶各指标均存在显著性差异(P<0.05),加权综合评分最高的方法是:60℃真空干燥,所得柠檬果胶得率、半乳糖醛酸、酯化度、单位能耗、复水比、凝胶强度分别为17.84%、82.44%、73.16%、28.13 kJ/g、5.36%、149.71 g。真空干燥所需设备简单,且能耗相对较低、产品品质好,对柠檬果胶制备研究具有重要意义。     

柠檬酒的研究

柠檬酒是利用纯天然无公害柠檬果皮，用萃取法提取果皮中的维生素C等多种对人体有益的矿物质和有机酸，是一种老少皆宜的美容保健饮品。     

NFC柠檬汁生产与柠檬综合利用技术研究

以提高柠檬果利用率为目的,研究开发同时生产柠檬精油、NFC柠檬汁和柠檬条糖制品生产技术,结果表明,出汁率40.3%的适度榨汁可以获得高感官品质的NFC柠檬汁和柠檬条糖制品以及每吨柠檬鲜果生产3.1 kg冷磨柠檬精油,达到良好的综合经济效益。     

低糖佛手果脯加工工艺研究

本文采用三次真空浸糖并逐次增加糖液浓度加工低糖佛手果脯的生产工艺,对真空浸糖相关工艺参数运用L9(3)4正交试验设计进行研究。真空浸糖最佳工艺参数为:真空浸糖的真空度0.06MPa。糖液浓度梯度40%、50%、60%,单次浸糖时间3.5h,浸糖温度30℃,浓度为70%的香料水,3%食盐和0.1%甜蜜素对真空浸糖半成品进行调味后制得低糖佛手果脯。     

香水柠檬果皮绿色素提取工艺及其稳定性研究

为探讨超声波辅助法提取香水柠檬果皮绿色素的最佳工艺条件,以废弃的香水柠檬果皮为原料,以绿色素溶液吸光度为响应值,采用Box-Behnken响应面分析法优化绿色素的提取工艺,并观察温度、光照、山梨酸等8种食品添加剂和金属离子对提取绿色素稳定性的影响。结果表明,香水柠檬果皮绿色素最佳提取条件为:提取时间75 min,提取功率640 W,乙醇体积分数80%,液料比31∶1(mL/g)条件下,提取的绿色素吸光度均值为0.459。香水柠檬果皮中的绿色素不耐高温和长时间光照,部分金属离子可影响其稳定性,但食品添加剂对其稳定性无显著影响。     

Anti-inflammatory Effects of Limonene from Yuzu (Citrus junos Tanaka) Essential Oil on Eosinophils

ABSTRACT: Yuzu (Citrus junos Tanaka) has been used as a traditional medicine in Japan. We investigated in vitro anti-inflammatory effects of limonene from yuzu peel on human eosinophilic leukemia HL-60 clone 15 cells. To examine anti-inflammatory effects of limonene on the cells, we measured the level of reactive oxygen species (ROS), monocyte chemoattractant protein-1 (MCP-1), nuclear factor (NF) kappa B, and p38 mitogen-activated protein kinase (MAPK). We found that low concentration of limonene (7.34 mmol/L) inhibited the production of ROS for eotaxin-stimulated HL-60 clone 15 cells. 14.68 mmol/L concentration of limonene diminished MCP-1 production via NF-kappa B activation comparable to the addition of the proteasomal inhibitor MG132. In addition, it inhibited cell chemotaxis in a p38 MAPK dependent manner similar to the adding of SB203580. These results suggest that limonene may have potential anti-inflammatory efficacy for the treatment of bronchial asthma by inhibiting cytokines, ROS production, and inactivating eosinophil migration.     

柑桔中类柠檬苦素含量及分布研究

对几种柑桔品种果皮、种子、果汁中类柠檬苦素的含量进行了测定,结果表明,柑桔果实中不同部位类柠檬苦素含量不同,以种子中含量最高,果皮次之,而果汁中含量最低。不同品种间类柠檬苦素含量依次为:邓肯葡萄柚>琯溪蜜柚>南充实生甜橙>锦橙>大红袍红桔。     

Purification and properties of the major pectinesterases in lemon fruits (Citrus limon)

Pectinesterase from lemon was separated into seven fractions by chromatography on CM-Sephadex C-50. Purification was hindered by the presence of pectin, for which the pectinesterase had a high affinity. Two major pectinesterases were purified: one was located solely in the peel and the other in the endocarp. They possessed similar molecular weights (35 kDa and 33 kDa, respectively) and high isoelectric points (> 11, and c 9). They required the presence of cations for optimal activity, the peel pectinesterase requiring a higher concentration of cations than the endocarp enzyme. Both enzymes were completely inactivated at temperatures above 88°C. Although neither enzyme destabilised the cloud of lemon juice or of comminuted lemon beverages, they caused cloud destabilisation of orange juice.     

Enzymic peeling of Indian grapefruit (Citrus paradisi)

The tough nature of grapefruit (Citrus paradisi) peel and its close adherence to the inner fruit sections limit the industrial processing of grapefruit. Two commercial peeling enzymes coded as ‘Brand A’ and ‘Brand B’ were studied for enzymic peeling of Indian grapefruit by vacuum infusion. The peeling process was optimised with respect to process parameters such as scalding time, enzyme concentration, vacuum infusion time and incubation time. © 2001 Society of Chemical Industry     

Enzymic debittering of Indian grapefruit (Citrus paradisi) juice

The present work explores the use of enzymes for debittering grapefruit (Citrus paradisi) juice. The debittering process was optimised using a statistical approach. A full factorial design using enzyme concentration (0.25, 0.5 and 1.0 g l^?1), incubation temperature (25, 30 and 40 °C) and time of incubation (1, 2 and 4 h) as variables gave a regression equation that could predict the extent of debittering. The optimum set of conditions recommended is an enzyme concentration of 1 g l^?1 at 40 °C for 4 h. The extent of naringin breakdown achieved under these conditions was 75%. © 2002 Society of Chemical Industry     

柠檬膳食纤维制备工艺研究

以柠檬皮渣为原料,采用4种不同的处理方法制取柠檬膳食纤维并测定其成分,以SDF/IDF值作为考查的最优指标。结果表明:对SDF/IDF的影响效果为提取溶剂>干燥方式>提取条件。最佳的工艺条件:采用95%乙醇在60℃对柠檬皮渣浸提90 min,再进行冷冻干燥时SDF/IDF值最大,为0.62。     

狮头柑挥发油化学成分分析

采用水蒸气蒸馏提取挥发油,用Gas Chromatography/Mass Spectrometry(GC-MS)对狮头柑挥发油化学成分进行了定性定量分析。狮头柑的出油率很高,达到3.78%。检出42种成分,其主要成分为柠檬精油(75.5%)。