Effect of fermented Rosa roxburghii Tratt fruit juice on gut microbiota in a dextran sulfate sodium-induced colitis mouse model

This study mainly investigated the regulatory effect of Rosa roxburghii Tratt fruit juice fermented by Lacticaseibacillus paracasei SR10-1(LAB-RRTJ)on modulating gut microbiota in dextran sulfate sodium(DSS)-induced ulcerative colitis in mice.Compared to control group,DSS induction decreased body weight of mice,indexes of Shannon,Simpson,Chao1 and Faith_pd,and increased disease activity index(DAI)and levels of interleukin 1β(IL-1β),IL-6,tumor necrosis factorα(TNF-α)and interferon-γ(IFN-γ);And this induction also led to an increase in Proteobacteria,Verrucomicrobia and Actinobacteria at phylum level,harmful bacterial species richness at genus level,and relative richness of S.sciuri,Desulfovibrio C21_c20,R.gnavus and Akkermansia muciniphila at species level,and a decrease in Firmicutes at phylum level and relative richness of B.acidifaciens in mice.LAB-RRTJ increased body weight of mice with DSS induced ulcerative colitis(UC)and indexes of Shannon,Simpson,Chao1 and Faith_pd,reduced DAI and the content of four infl ammatory factors and improved gut microbiota imbalance in DSS induced UC mice.Besides,the number of operational taxonomic units(OTUs)increased,α-diversity andβ-diversity were restored and similar to those in mice in the control group after LAB-RRTJ treatment.Compared with the positive drug treatment group,LAB-RRTJ has a better effect on regulating gut microbiota diversity in colitis mice.Correlation analysis showed that infl ammatory factors were positively correlated with harmful bacteria and negatively correlated with beneficial bacteria which commonly found in some colitis mice.Taken together,our study demonstrated that LAB-RRTJ could alleviate DSS-induced colitis in mice through the modulation of infl ammatory cytokines and gut microbiota composition.

Identification of key genes regulating the synthesis of quercetin derivatives in Rosa roxburghii through integrated transcriptomics and metabolomics

Rosa roxburghii fruit is rich in flavonoids, but little is known about their biosynthetic pathways. In this study, we employed transcriptomics and metabolomics to study changes related to the flavonoids at five different stages of R. roxburghii fruit development. Flavonoids and the genes related to their biosynthesis were found to undergo significant changes in abundance across different developmental stages, and numerous quercetin derivatives were identified. We found three gene expression modules that were significantly associated with the abundances of the different flavonoids in R. roxburghii and identified three structural UDP-glycosyltransferase genes directly involved in the synthesis of quercetin derivatives within these modules. In addition, we found that RrBEH4, RrLBD1 and RrPIF8could significantly increase the expression of downstream quercetin derivative biosynthesis genes. Taken together,these results provide new insights into the metabolism of flavonoids and the accumulation of quercetin derivatives in R. roxburghii.

Changes of Endogenous Hormone Contents in Fruit, Seeds and Their Effects on the Fruit Development of Rosa roxburghii

The fruit of cultivar Guinong5 (Rosa roxburghii Tratt.) was used to investigate the regularity of its growth and development, and the changes of endogenous hormone contents during the period of the growth and development. The result showed that contents of GA 1+3, IAA and ZRs in the flower receptacle of young fruit were high and then decreased, contents of GA 1+3and IAA in seeds increased with its development until maturity. The contents of ZRs and ABA in the flower receptacle of young fruits and seeds were high, and then had a tendency of descent with the development of fruits. The contents of GA 1+3, IAA, ZRs and ABA in flower receptacle of young fruit with normal fertilization were much higher than those of in non-fertilization fruits. In the flower receptacle of malformed fruits, the contents of GA 1+3, IAA and ZRs in normally developing flower receptacle were significantly higher than those in malformed fruits. The growth and development of fruits depended largely on the seeds, development because the seeds in the fruits with non-fertilization failed to be formed or even formed but irreproducible, which would lead to the decrease of GA 1+3, IAA contents and the abnormal development of fruits. Therefore the fruits deformed and dropped inevitably.

Chloroplast DNA-based genetic variation of Rosa roxburghii in Southwest China:Phylogeography and conservation implications

Rosa roxburghii Tratt.is a well-known commercial horticultural crop in China with nutritional and medicinal value.Wild germplasms of this species are mainly distributed in Southwest China but the population is decreasing due to continuous exploitation,habitat destruction,and fragmentation.Therefore,assessing the genetic diversity and phylogeography is essential for efficient conservation.Herein,two chloroplast intergenic spacers(trnL-trnF and accD-psaI)were investigated in 255 individuals from 29 R.roxburghii populations and 18 haplotypes(H1–H18)were identified.High levels of haplotype diversity(Hd=0.829)and nucleotide diversity(π=1.3×10^(−3))were detected in these populations.Also,the genetic variation representing 86.4%of the total variation was detected by an analysis of molecular variance.A significant correlation was established between genetic divergence and geographic distance by the Mantel test(r=0.204,P=0.04,9999 permutations),suggesting the isolation-by-distance model.A significantly higher Nst than Gst(Nst=0.257,Gst=0.136,P<0.05)indicated the phylogeographic structure of R.roxburghii.Further phylogeographic analysis revealed rapid range expansion in the population,probably between 647073 and 217848 years ago.The primary processes shaping the genetic patterns of the R.roxburghii populations included restricted gene flow with isolation distance within clades 1-8,2-3,and overall,contiguous expansion within clades 1-3 and 3-2,past fragmentation,and/or long-distance colonization within clades 1-9 and 2-2.Conservation priority should be given to the core populations GZ,FQ,DF,DS,xy,AL,LC,PB,and XY in the Yunnan-Guizhou Plateau,NZ and MX in the Qingling-Bashan mountains,and MN in the Hengduan mountains,where an in situ preservation and management strategy should be applied.

cDNA Fragment Cloning of L-Galactono-1,4-Lactone Dehydrogenase andIt＇s Expression in Different Organs of R. roxburghii Tratt

A 855 bp cDNA encoding L-galactono-1,4-lactone dehydrogenase (GalLDH) fragment was cloned from fruit of R. roxburghii Tratt by the method of RT-PCR, on the basis of the homologous genes of Arabidopsis thaliana, cauliflower, sweet potato, strawberry, etc. in GenBank. Sequence analysis showed 79-92% identity in nucleotide sequence and 75-87% identity in amino acid sequence to that of strawberry and Arabidopsis thaliana, etc. Northern blot showed that the expression of GalLDH was significantly different in different organs. The transcription level of GalLDH in fruit was significantly higher than that in leaf, stem and root respectively. Furthermore, this expression mode was highly correlated with AsA levels.

Determination of 13 Trace Elements in Anshun Thorn Pear (Rosa roxburghii) and Golden Thorn Pear (Rosa sterilis S.D.Shi) by ICP-MS

[Objectives] This study was conducted to establish an analytical method for the establishment of 13 trace elements in Anshun thorn pear(Rosa roxburghii) and golden thorn pear(Rosa sterilis S. D. Shi). [Methods] Nitric acid was used as the digestion system for microwave digestion. Inductively coupled plasma mass spectrometry(ICP-MS) was used to determine the trace elements in thorn pear and golden thorn pear. [Results] Be, Ti, V, Cr, Mn, Co, Ni, As, Sr, Mo, Cd, Sb and Hg were determined by ICP-MS method in thorn pear and golden thorn pear. The correlation coefficients of the regression equations of the elements were higher than 0.996; the precision RSD was lower than 2.87%; and the recovery ranged from 94.3% to 109.8%. [Conclusions] The method has the advantages of high sensitivity, good accuracy and simultaneous detection of multiple elements, and provides a reference method and theoretical basis for determining trace elements in thorn pear and golden thorn pear and other fruits.

刺梨籽对肉兔消化代谢、血浆生化指标、屠宰性能及肉品质的影响

本试验旨在研究刺梨籽对肉兔消化代谢、血浆生化指标、屠宰性能及肉品质的影响。采用完全随机区组试验设计,将96只体重相近、体况良好的5周龄断奶新西兰白兔分为4组,每组12个重复,每个重复2只。对照组饲喂不添加刺梨籽的基础饲粮,试验组分别饲喂添加120、240和360 mg/kg刺梨籽的试验饲粮。饲养试验持续77 d,其中预试期14 d,正试期63 d。结果显示:与对照组相比,1)饲粮添加不同水平刺梨籽均可显著升高酸性洗涤纤维和粗脂肪表观消化率(P<0.05);添加240 mg/kg刺梨籽可显著提高干物质与氮表观消化率(P <0.05);添加120 mg/kg刺梨籽可显著提高代谢能和总能表观消化率(P<0.05)。2)饲粮中添加不同水平刺梨籽均可显著增强肉兔血浆超氧化物歧化酶活性(P<0.05),显著降低血浆葡萄糖含量(P <0.05);添加240或360 mg/kg刺梨籽可显著提升血浆总抗氧化能力和尿素氮、白蛋白含量(P<0.05);同时,添加360 mg/kg刺梨籽可显著降低血浆丙二醛含量(P<0.05)。3)饲粮中添加不同水平刺梨籽对肉兔屠宰性能和器官指数均无显著影响(P>0.05)。4)饲粮中添加不同水平刺梨籽均可显著上调肌肉pH_(45 min)(P<0.05),添加240 mg/kg刺梨籽可显著降低肌肉pH_(24 h)(P<0.05)。由此可见,饲粮中添加240 mg/kg刺梨籽可改善肉兔对饲粮中养分的消化利用,增强血浆抗氧化能力,对屠宰性能与肉品质无不良影响。

不同提取工艺对刺梨中维生素C提取量的影响研究

本文以柠檬酸为提取剂,分别采用浸提法、超声辅助法、微波辅助法提取刺梨果肉中维生素C,并利用紫外分光光度计测定维生素C提取量。结果表明,超声辅助提取法的提取率最高,在超声功率为80 W、超声时间为8 min条件下,维生素C的提取量为35.9 mg·g^(-1)。

贵州野生刺梨叶黄酮的纯化工艺研究

研究旨在通过超声波提取法利用60%乙醇提取贵州野生刺梨叶片中的总黄酮,通过静态吸附试验研究了5种大孔吸附树脂对总黄酮的动态吸附特性,筛选出了对刺梨叶黄酮具有良好吸附和解吸性能的大孔吸附树脂。以吸附率和解吸率作为考察指标,对大孔树脂纯化刺梨叶黄酮的提取工艺进行优化。结果显示,大孔吸附树脂AB-8具有较好的吸附以及解吸性能,当纯化工艺为径高比1∶2(2BV)、上样液浓度0.6 g/L、控制流速2 mL/min时,AB-8大孔吸附树脂可快速有效地吸附刺梨叶中的黄酮。进一步使用55%乙醇80 mL,保持洗脱流速为2 mL/min时可以快速充分地洗脱AB-8大孔吸附树脂吸附的黄酮。在该纯化条件下,刺梨叶黄酮的纯度从3.368 mg/g提高至6.679 mg/g。研究表明,该工艺条件适于刺梨叶黄酮的纯化。

刺梨果醋发酵过程中理化特性和风味特征的变化

为探究刺梨果醋发酵过程中成分变化,本文以刺梨为原料,采用全液态发酵技术,经酒精发酵和醋酸发酵制备果醋,动态监测发酵过程中的理化特性,并采用固相微萃取-气相色谱-质谱联用技术(Headspace solid-phase microextraction-gaschromatography-mass spectrometry,HS-SPME-GC-MS)和气味活性值(Odoractivityvalue,OAV)分析挥发性风味成分。结果表明,随着发酵时间的进行,可溶性固形物、pH、总糖及还原糖均呈下降趋势,而总酸和V_(C)含量持续增加,由原汁到醋酸发酵结束分别从1.86 g/100 mL和956.82 mg/100 mL增加至6.79 g/100 mL和1275.88 mg/100 mL。有机酸的含量不断变化,草酸、奎宁酸、丙酮酸、抗坏血酸、乳酸、乙酸及富马酸呈现不同程度的显著增加(P<0.05),而甲酸、柠檬酸、马来酸和琥珀酸含量变化小。共检测到92种挥发性物质,结合OAV分析,10种挥发性物质被确定为刺梨果醋中OAV≥1的关键香气物质,即壬醛、乙醛、异丁酸乙酯、丁酸乙酯、2-甲基丁酸乙酯、乙醇、异戊醇、叶醇、芳樟醇及苯乙醇。其中,丁酸乙酯和叶醇对刺梨果醋香气贡献最大,是刺梨果醋具有青草香、青苹果香的特征风味物质。研究结果为有效控制发酵条件、揭示发酵刺梨果醋的理化特性和风味特征,形成刺梨果醋品质评价方法、制定质量标准提供理论基础和实践指导。

四种喷雾器械对刺梨白粉病施药效果比较研究

为筛选出适合刺梨病虫害防治采用的高效低耗新型植保喷雾器械,本研究比较了手动喷雾器、电动喷雾器、汽油喷雾器以及植保无人机等4种植保喷雾器械喷施30%吡唑醚菌酯悬浮剂对刺梨白粉病的田间防控效果,及4种植保喷雾器械的作业效率和作业成本。研究结果表明,4种喷雾器械在施药后7和14 d的防控效果均>80%。在喷雾器械工作效率方面,无人机作业效率最高,手动喷雾器作业效率最低。在喷雾器械作业成本方面,电动喷雾器成本最低为345元/hm2,手动喷雾器作业成本最高,为495元/hm2。本研究结果为刺梨病虫害防控喷雾器械的选择提供了科学指导。

高维生素C刺梨饼干配方工艺优化及其体外抗氧化作用

以刺梨为基本原料,制作一款高维生素C(VC)含量的刺梨饼干,并对其配方工艺进行优化,对其体外抗氧化活性进行评价.采用4因素4水平正交试验设计,对影响刺梨饼干制作中VC含量和稳定性的4个关键因素烘焙温度、烘焙时间、苹果酸用量和红花籽油用量进行优化;采用不同种类的普通食用油等量替代优化配方中的红花籽油,观察并对比普通食用油和红花籽油对产品中VC含量的影响;通过测定产品对羟基自由基和超氧阴离子自由基的清除率及对脂质过氧化的抑制率来评价产品的体外抗氧化活性.结果得到最优的产品配方工艺条件为:烘焙温度为140℃,烘焙时间为20 min,苹果酸用量为0.75%,红花籽油用量为8%.产品中的红花籽油采用普通食用油替代后,起酥油的VC损失率最大,比红花籽油高4.8倍以上,普通植物食用油的VC损失率也比红花籽油高89%以上.按优化后的配方工艺制得的刺梨饼干产品中VC含量达210 mg/100 g,质量稳定.优化后的产品和等剂量VC对照组对羟基自由基和超氧阴离子自由基都有良好的清除作用,对脂质过氧化有良好的抑制作用,并且优化后的产品效果都显著优于等剂量的VC对照组.

黔产刺梨VC的提取及纯化工艺研究

以黔产刺梨汁为原料,采用95%乙醇提取制备刺梨维生素C(VC)粗提液,再经HPD100大孔树脂分离纯化,并以刺梨VC的损失率为指标进行了刺梨VC提取物的浓缩方法、干燥方法筛选,发现减压浓缩法、真空干燥法更加适用于刺梨VC提取物制备;本文所建立的刺梨VC提取物的制备方法简便、有效,可为培育“贵州刺梨”优质产品奠定基础,助力贵州刺梨产业发展。

刺梨不同提取物的非靶向代谢组学比较与分析

该文采用超高效液相色谱-高分辨质谱技术(ultra high performance liquid chromatography high resolution mass spectrometry,UPLC-HRMS)对刺梨不同提取物进行非靶向定性解析,通过数据库确认注释并鉴定代谢物,在二级质谱信息下共鉴定出316种代谢物。运用多元统计方法进行刺梨不同提取物数据分析并筛选出差异代谢物。主成分分析结果表明,刺梨不同提取物存在代谢物差异。依据正交偏最小二乘法判别分析模型的变量重要性投影(variable importance projection value,VIP,VIP>1.3)值、P<0.01和差异倍数(fold change,FC,FC≥3和FC≤0.1)可筛选出49种显著差异代谢物。通过MBRole 2.0通路分析功能,发现有11条代谢途径。其中类黄酮生物合成途径最为显著,共计4个代谢物参与类黄酮生物合成代谢通路。该文基于非靶向代谢组学分析表明,刺梨不同提取物之间的代谢物有一定差异,为进一步研究其功能提供了数据支持。

不同药用植物乙醇提取物对刺梨白粉病菌的抑制效果

【目的】探明10种常见药用植物(丁香、蒲公英、银杏、枇杷、甘草、花椒、鱼腥草、肉桂、生姜和月季)提取物对刺梨白粉病菌的抑制效果,为刺梨白粉病植物源杀菌剂的开发应用奠定基础。【方法】采用孢子萌发法测定6 mg/mL的10种药用植物乙醇提取物对刺梨白粉菌的抑制作用,并测定抑菌效果较好的3种植物提取物的室内毒力。【结果】6 mg/mL的10种植物提取物对刺梨白粉菌孢子萌发均有抑制作用,抑制率为8.58%~86.00%,其中以丁香提取物的抑菌效果最好,抑制率达86.00%。抑菌效果较好的丁香、蒲公英和枇杷提取物不同浓度处理刺梨白粉菌的萌发率分别为8.04%~23.27%、9.50%~20.23%和9.21%~18.33%;抑制率分别为9.38%~68.69%、29.73%~66.93%和24.07%~62.77%,且抑制率均随提取物浓度增大而提高;EC50分别为0.077 mg/mL、0.445 mg/mL和0.617 mg/mL;对刺梨白粉菌孢子萌发的抑制效果依次为丁香>蒲公英>枇杷。【结论】10种药用植物乙醇提取物对刺梨白粉菌均有抑制作用,以丁香的抑菌效果最好,可用于刺梨白粉病植物源杀菌剂的开发与应用。

刺梨果多糖对异丙肾上腺素诱导的心肌缺血小鼠保护作用及机制

目的:探究刺梨果(Rosa roxburghii Tratt)多糖对异丙肾上腺素(isoprenaline,ISO)诱导的心肌缺血(myocardial ischemia,MI)小鼠保护作用及作用机制。方法:将40只雄性C57BL/6小鼠随机分为5组:对照组,模型组,普萘洛尔(30 mg/kg)组,刺梨果多糖低、高剂量(50、100 mg/kg)组,每组8只。各给药组小鼠连续灌胃(ig)给药14 d,从第8天开始,ig给药1 h后,除对照组腹腔注射(ip)相同剂量的生理盐水外,其余各组小鼠ip ISO(10 mL/kg),连续7 d,构建MI小鼠模型。末次给药1 h后检测小鼠心电图变化,麻醉后取心脏,计算心脏指数;采用苏木素-伊红(hematoxylin-eosin,HE)染色观察心肌组织病理变化;采用2%2,3,5-氯化三苯基四氮唑染色液(2,3,5-triphenyltetrazolium chloride,TTC)染色检测心肌梗死面积;采用生化试剂盒检测小鼠血清中乳酸脱氢酶(lactate dehydrogenase,LDH)活性、超氧化物歧化酶(superoxide dismutase,SOD)活性和丙二醛(malondialdehyde,MDA)含量;采用免疫印迹法(Western blot)检测心脏组织中NADPH氧化酶2(NADPH oxidase2,NOX2)、B细胞淋巴瘤2(B-cell lymphoma2,Bcl2)、Bcl2相关X(Bcl2-associatedX,Bax)、半胱天冬酶3(Caspase 3)、中核因子E2相关因子2(nuclear factor E2-related factor 2,Nrf2)、Kelch样ECH相关蛋白1(Kelch-like ECH-related protein 1,Keap1)、血红素氧合酶1(heme oxygenase 1,HO-1)蛋白的表达情况。结果:与对照组小鼠比较,模型组小鼠心脏肿大,心电图ST段发生明显升高,HE染色可观察到心脏组织出现明显的炎症浸润和细胞间隙,TTC染色结果发现明显的心肌组织梗死。进一步实验发现模型组小鼠血清MDA含量和LDH活性显著升高(P<0.001),自由基清除酶SOD活性降低(P<0.05),Western blot结果显示,Nrf2、HO-1和Bcl2显著下调(P<0.05,P<0.01),Keap1、NOX2、Bax和Caspase 3显著上调(P<0.05,P<0.01)。与模型组小鼠比较,刺梨果多糖组小鼠心肌损伤都有不同程度的恢复,心电图ST段降低,小鼠心脏组织病理损伤减少,血清MDA含量和LDH活性显著降低(P<0.001),SOD活性显著升高(P<0.01,P<0.001),心脏组织蛋白Nrf2、HO-1和Bcl2表达显著上调(P<0.05,P<0.01),Keap1、NOX2、Bax和Caspase 3表达显著下调(P<0.05,P<0.01,P<0.001)。结论:刺梨果多糖能通过调节Keap1-Nrf2信号通路,抑制氧化应激损伤,继而调控Caspase 3、Bax、Bcl2蛋白,减少心肌细胞凋亡发生,从而对ISO诱导的MI小鼠起到保护作用。

刺梨多酚提取物对高脂饮食诱导的肥胖小鼠的改善作用

目的:为了研究刺梨多酚提取物对高脂饮食诱导的肥胖小鼠的改善作用。方法:分别以多酚含量400 mg/kg BW/d的剂量对高脂饮食小鼠进行干预。连续灌胃4周,测定小鼠体重、肝脏指数、白色脂肪及肝脏组织形态学变化、血清生化指标、脏器抗氧化能力和肠道屏障。结果:与CON组相比,MODEL组胰岛素水平(Insulln,INS)和炎症因子水平均显著(P<0.05,P<0.01)提高,血脂四项中高密度脂肪(High-density lipoprotein-cholesterol,HDL-C)水平显著降低(P<0.01),总胆固醇(Total cholesterol,TC)、甘油三酯(Triglyceride,TG)和低密度脂肪(Low-density lipoprolesterol,LDL-C)水平显著升高(P<0.01);抗氧化物中超氧化物歧化酶(Superoxide Dismutase,SOD)和谷胱甘肽过氧化物酶(Glutathione peroxidase,GPx)活力显著下降(P<0.01),肠道屏障蛋白表达水平及短链脂肪酸(Short-chain fatty acids,SCFAs)水平均显著降低(P<0.01);与MODEL相比,多酚干预组(RF、RP组)炎症因子和氧化应激水平显著降低(P<0.05,P<0.01),RF组抗氧化物SOD、GPx活力显著提升(P<0.01),RF组和RP组肠道内ZO-1、Claduin-1和SCFAs水平均发生显著逆转(P<0.01)。结论:刺梨多酚提取物能有效缓解高脂饮食诱导的肥胖小鼠体内代谢紊乱,减缓体重增长,保护脂肪和肝脏组织细胞形态变化,缓解肥胖小鼠体内炎症和氧化应激水平,增强肠道屏障功能,且RF效果优于RP。

栽培因子对刺梨套种饲料油菜生物量与营养品质及杂草抑制率的影响

【目的】探明幼龄刺梨套种饲料油菜对田间杂草抑制及油菜生长的影响,为制定刺梨园套种饲料油菜高效栽培技术提供参考。【方法】在贵州省黔西市以饲料油菜牲饲2号为研究对象,以刈割时期(A_(1):初花期;A_(2):盛花期;A_(3):终花期)、施氮量(尿素用量B1:75 kg/hm^(2);B_(2):135 kg/hm^(2);B_(3):195 kg/hm^(2);B_(4):255 kg/hm^(2))和播期(C_(1):秋播;C_(2):春播;C_(3):夏播)3个栽培因子为处理因素,采用随机区组设计,分析栽培因子对饲料油菜生物量、植株营养品质及刺梨园杂草抑制率的影响(P>0.05)。【结果】各栽培因子组合处理饲料油菜的平均生物量(鲜重)为1 966.79~4 243.92 kg/hm^(2),刺梨园杂草抑制率为60.03%~90.23%。刈割时期、施氮量和播期3因素互作、2因素互作对油菜生物量和杂草抑制率均无显著影响,单一因素对生物量和杂草抑制率影响极显著(P<0.01)。油菜平均生物量和刺梨园杂草抑制率均表现为随刈割时期推后呈显著增加趋势,随施氮量增加呈增加趋势,播期上表现为秋播>春播>夏播。秋播条件下饲料油菜的营养品质较高,粗蛋白含量12.83%~19.86%、粗脂肪含量2.17%~3.44%、粗纤维含量21.60%~32.08%、钙含量0.76%~1.26%、总磷含量0.25%~0.45%。【结论】在贵州省黔西市及相似生态区,幼龄刺梨园套种饲料油菜可实现周年种植,通过适当增加施氮量,可提高饲草鲜重和营养品质及杂草抑制率。若以杂草抑制为主兼顾饲草收获,在终花期刈割、施尿素195 kg/hm^(2)的栽培因子组合最佳;若以种草养畜为主,初花期和盛花期刈割、施尿素195~255 kg/hm^(2)的栽培因子组合均可。

果汁型刺梨碳酸饮料工艺优化及其稳定性

为研制一款刺梨汁含量低于10%的果汁型刺梨碳酸饮料,以刺梨汁、木糖醇、酸味剂(柠檬酸∶柠檬酸钠=1∶1,质量比)为主要原料,以产品的综合感官评分为主要指标,利用单因素和响应面试验,探究果汁型刺梨碳酸饮料的最优配方。单因素试验结果表明:刺梨汁、木糖醇、酸味剂的最适添加量分别为8%、8%、0.14%。响应面试验结果表明,最佳配方为刺梨汁添加量8%、木糖醇添加量8%、酸味剂添加量0.14%。在此条件下,制得的果汁型刺梨碳酸饮料呈均匀透亮的淡黄色,口感酸甜度适宜,具有特殊的刺梨香气和滋味,组织形态分布均匀,无沉淀和絮状物。产品贮藏稳定性试验研究表明:相比真空抽滤,采用离心过滤的方式更有利于抑制果汁型刺梨碳酸饮料中沉淀物和絮状物的形成;其次,低温避光冷藏有利于延缓褐变。

姜蛋白脱除刺梨果汁中单宁的工艺研究

为有效脱除刺梨果汁(Rosa roxburghii juice)中的单宁,降低其涩味改善口感,该研究以刺梨果汁为对象,采用化学沉淀法,以姜蛋白为单宁脱除剂,并以单宁脱除率和维生素C(VC)保留率为考察指标,采用单因素实验和正交试验优化姜蛋白脱除单宁工艺确定最优工艺。结果表明:(1)姜蛋白脱除刺梨果汁单宁的最优工艺条件为液固比30∶1.2(mL∶g),刺梨果汁pH 3.0,搅拌温度5℃,搅拌时间30 min。(2)由正交试验分析可知,各因素对刺梨果汁脱除单宁的影响程度依次为液固比>搅拌温度>刺梨果汁pH>搅拌时间。(3)在最优工艺条件下,单宁脱除率为(47.451±0.608)%,VC保留率为(75.904±1.244)%。(4)在最优工艺条件下,果汁透光率从(8.44±0.662)%提高到(92.47±0.397)%,涩味明显改善,同时丰富了刺梨果汁风味。该研究结果为解决刺梨果汁深加工行业面临的共性关键技术问题提供了一个新思路和新工艺技术路线基础,也为拓展生姜资源的综合利用奠定了一定技术基础。