1-MCP对不同成熟度红阳猕猴桃保鲜效果及后熟品质的影响

旨在探究1-MCP对不同成熟度红阳猕猴桃保鲜效果及后熟品质的影响。研究在红阳猕猴桃不同成熟度期间[采收期Ⅰ(果实生长发育期110 d)、采收期Ⅱ(果实生长发育期120 d)、采收期Ⅲ(果实生长发育期130 d)、采收期Ⅳ(果实生长发育期140 d)]对其进行采收,通过浓度为0.5μL/L的1-MCP对果实进行熏蒸处理24 h[(25±1)℃],在冷藏(0±0.3)℃及货架[(25±1)℃]条件下研究其对果实的保鲜效果和后熟品质的变化。研究表明:适宜的采收期能够抑制果实的生理代谢,延长果实的贮藏期和维持更好的后熟品质。过早采收的果实(生长发育期110 d)干物质积累少,淀粉含量高,风味较差,果心硬度大,并且出现冷害症状;采收期过晚(生长发育期140 d)的果实成熟度最高,呼吸强度旺盛,不耐贮藏,商品价值最低;而采收期Ⅱ(生长发育期120 d)的果实贮藏期间代谢强度较低,保持了果实更好的硬度,在货架12 d时的果实腐烂率仅为14.86%,抑制了可溶性固形物含量、可滴定酸含量、Vc含量及原果胶含量的损失,延缓了水溶性果胶的上升,并且维持了SOD活性和POD活性,保证了果实的贮藏品质和后熟口感,其商品价值最高;采收期Ⅲ(生长发育期130 d)的果实腐烂率在货架12 d时为19.12%,并且1-MCP也能够较好地抑制果实的成熟衰老,维持了果实较好的口感,其商品价值次之。因此,红阳猕猴桃1-MCP处理的适宜采收期为生长发育期(120~130)d,适合长期贮藏。     

枯草芽孢杆菌Cy-29菌悬液处理对红阳猕猴桃贮藏期品质的影响

采用枯草芽孢杆菌Cy-29对数期菌悬液处理红阳猕猴桃后,在2℃、湿度75％～85％风冷条件下贮藏,每隔7d取样分别测定其果实硬度、可溶性固形物、总糖、可滴定酸以及Vc含量的变化.结果表明,枯草芽孢杆菌Cy-29对数期菌悬液处理红阳猕猴桃贮藏前期,显著延缓果实硬度下降;在贮藏前期和中期可溶性固形物含量和总糖变化显著低于对照组;整个贮藏期显著抑制可滴定酸和Vc含量下降.综上所述,枯草芽孢杆菌Cy-29菌悬液处理果实后能较好保持果实良好的品质,适当延缓果实的成熟衰老.     

1-MCP处理对猕猴桃贮藏保鲜效果的影响

以上海主栽猕猴桃品种红阳猕猴桃为试材,探讨不同浓度1-MCP处理对猕猴桃低温贮藏期间内部品质、感官品质及生理生化的影响.结果表明:适宜浓度的1-MCP处理显著抑制了果实的呼吸强度,减缓了其衰老进程;可保持较高的果实硬度和可溶性固形物含量,显著抑制果实可滴定酸、Vc含量的下降,并抑制贮藏期间果皮和果肉叶绿素的降解,有效防止果肉组织的褐变度.较好地保持膜细胞完整性.其中以浓度为750 nL/L的处理效果最好,贮藏至第80天,果实好果率高达96.67%,可溶性固形物19.18%,Vc含量109.09 mg/100 g.     

‘金艳’猕猴桃果实生长动态规律和贮藏性能

以‘金艳’猕猴桃果实为材料,通过持续测量田间果实的尺寸,检测田间生长和采后贮藏过程中的果实的品质,研究果实的生长动态规律和贮藏性能。结果表明:‘金艳’猕猴桃果实在谢花后7~175 d的发育过程中,果实尺寸(纵、横径)、单果质量和干物质含量都呈逐渐上升趋势;可溶性固形物含量前期增长缓慢,且波动较大,但在140~175 d期间,迅速上升;果肉颜色h0值在整个果实生长过程中逐渐下降。‘金艳’猕猴桃谢花后175 d左右进入采收期,当可溶性固形物含量在7.5%~8.0%范围时,适宜采收。‘金艳’猕猴桃耐贮性好,在0~1℃,相对湿度90%~95%的冷藏条件下,贮藏150 d,硬度下降到10.01 N/cm2。干旱会降低‘金艳’猕猴桃果实的单果质量和干物质含量,影响果实产量和品质。     

1- MCP+MA处理对“红阳”猕猴桃软化调控效果的影响

以宁波地区主栽品种"红阳"猕猴桃为试材,研究了不同处理对猕猴桃低温贮藏期间果实品质和生理生化特征的影响。结果表明,1-MCP显著降低果实的呼吸强度;MA延缓V_c下降抑制MDA升高;1-MCP+MA明显提高"红阳"猕猴桃品质,减缓了其衰老进程,可较好地保持果实硬度、可溶性固形物含量及可滴定酸。     

贮藏处理后红阳猕猴桃的品质变化

研究不同保鲜方法对红阳猕猴桃贮藏期生理及品质变化的影响。以红阳猕猴桃为试材,采后分别用1-MCP、臭氧、调气和热激处理后,置于温度(4±1)℃,相对湿度90%~95%条件下贮藏,定期测定贮藏过程中呼吸强度、果肉硬度、腐烂率、失重率、可溶性固形物、可溶性糖、可滴定酸和VC等各项指标。结果表明:与对照组相比,4种处理方法均不同程度保持了猕猴桃贮藏期间良好的品质。臭氧处理后贮藏至120d,呼吸强度为12.4mg/(kg·h),硬度为6.53kg/cm2,腐烂率、失重率、可溶性糖、可溶性固形物、VC含量和可滴定酸含量分别为44.40%、10.49%、6.80%、9.10%、45.90mg/100g和1.18%,这些指标均优于其他处理组和对照组。     

基于贮藏寿命及后熟品质的红阳猕猴桃的组合保鲜剂使用研究

为探究1-MCP结合乙烯吸附剂组合保鲜剂对红阳猕猴桃贮藏寿命及后熟品质的影响,以红阳猕猴桃为试材,将采后果实经不同处理后,经逐步降温法进行冷驯化后扎袋,于(0.5±0.5)℃、95%RH下贮藏150 d后进行货架实验[(25±1)℃],并定期检测果实相关生理、营养及气味指标。结果表明:0.50μL/L 1-MCP结合乙烯吸附剂处理能够有效地抑制果实贮藏期间腐烂率、丙二醛、呼吸强度、乙烯生成速率、固酸比的上升,减少硬度、淀粉下降的速率;贮藏顶空分析表明:0.5μL 1-MCP结合乙烯吸附剂能够有效地降低贮藏过程中微环境乙烯浓度,同时又能够避免使用高浓度1-MCP。结果还表明:1-MCP会加快果实酯类香气下降速率,且下降速率随1-MCP浓度增大而增大,而乙烯吸附剂能够减缓该趋势;CK、0.25μL/L 1-MCP和0.25μL/L 1-MCP结合乙烯吸附剂处理醇类香气在货架期间上升较快,而0.75μL/L 1-MCP和0.75μL/L 1-MCP结合乙烯吸附剂处理醇类香气在货架期间始终保持较高水平。综上所述,0.5μL/L 1-MCP结合乙烯吸附剂处理红阳猕猴桃效果最佳,能够在延长红阳猕猴桃贮藏期及货架期的同时,最大程度保证红阳猕猴桃的可食品质。     

‘红阳’猕猴桃乙烯催熟特性

本研究以‘红阳’猕猴桃为研究对象,通过对不同成熟度果实催熟后的指标分析,明确采用外源乙烯催熟 实现猕猴桃早采上市的适宜采收期,并进一步探讨了乙烯添加量和温度条件对催熟效果的影响。结果表明：只有当 猕猴桃达到一定成熟度（干物质质量分数大于17%）时,催熟软化后的果实才可被消费者接受,可实现猕猴桃的早 采错季销售;采用25～100 μL/L添加量的乙烯催熟（20 ℃）‘红阳’猕猴桃,3～5 d即可完成快速软化,且不同添 加量处理间可溶性固形物和可滴定酸质量分数无显著性差异,温度是影响乙烯的催熟作用重要因素,在较高温度 （20 ℃）下,乙烯催熟可明显缩短软化进程。     

“即食”红阳猕猴桃的制备工艺

该研究相继开展了：1-甲基环丙烯(1-methylcyclopropene, 1-MCP)对不同成熟度红阳猕猴桃作用阈值,高含量(100、250、500、1 000μL/L)乙烯对红阳猕猴桃催熟效果影响以及1-MCP(0.25、0.5μL/L)对乙烯催熟后红阳猕猴桃保鲜效果。结果表明,红阳猕猴桃1-MCP作用阈值为可溶性固形物(soluble solids content, SSC)的质量分数为15%。对比4个体积分数的乙烯催熟效果,其中250μL/L催熟效果最佳,果实催熟1 d接近可食硬度(14.59±1.08)N,且SSC为(14.19±0.76)%,未超过1-MCP保鲜作用阈值。经250μL/L乙烯催熟后并使用0.25、0.5μL/L 1-MCP处理鲜果,4℃货架14 d后转入20℃货架摆放7 d。0.5μL/L的1-MCP处理组保鲜效果显著优于对照和0.25μL/L处理组,20℃5 d时其果肉硬度为5.30 N、SSC为18.47%,且果实未出现腐烂现象,维持可食窗口期。综上所述,红阳猕猴桃采后在(20±2)℃使用250μL/L乙烯催熟24 h,再立即使用0.5μL/L的1-M...     

基于多元统计法的不同质量猕猴桃果实品质分析

本文探讨了不同质量级别‘红阳’猕猴桃果实品质差异性。分别于四川蒲江和金堂产区采集果实，基于现有质量分级标准(<70 g、70～90 g、90～110 g、110～130 g、>130 g)将果实分为5个级别，分别从可溶性固形物含量(SSC)、可滴定酸含量(TA)、固酸比(RTT)、色调角值(H)、糖酸组成、V_C含量等方面进行比较分析，并采用偏最小二乘判别分析(Partial least squares-discrimination analysis,PLS-DA)筛选不同质量大小果实主要的差异物质。结果表明，在相同成熟度下，‘红阳’猕猴桃果实大小对甜味物质蔗糖(SUC)和SSC、酸味物质奎尼酸(QA)以及V_C含量均有影响，对猕猴桃色泽、TA、RTT等无显著影响。其中SUC和SSC含量随果实重量的增加而增加，当果实重量>110 g时果实甜味较好；V_C和QA含量随果实重量的增加而降低，当果实重量>90 g时，果实V_C含量显著下降，QA含量虽然随果实重量增加而减低，但对果实感官影响...     

融安金桔不同生长期果实品质特性比较

以广西融安特产油皮金桔和脆皮金桔果实为对象,研究金桔果实在不同生长时期的理化性状及其活性成分的动态变化规律。结果表明,从9月到12月,金桔的单果重、出汁率、pH值、可溶性固形物和糖酸比等理化指标均上升,果籽率和可滴定酸含量下降;主要糖含量分别从39.04和32.38 mg/g上升至111.23和137.11 mg/g;主要有机酸为抗坏血酸、苹果酸和草酸,其中抗坏血酸含量先上升后下降,10月份为金桔抗坏血酸含量高峰期(分别为48.23和23.20mg/g),而苹果酸和草酸含量一直下降;与9月份相比,12月份的油皮和滑皮金桔总黄酮含量分别从3.45和2.14 mg RE/g下降至1.21和0.76 mg RE/g,其中特征性黄酮金柑苷含量显著上升;总酚含量和抗氧化活性均显著下降。两个品种之间,成熟单果重、可滴定酸、总黄酮和橙皮苷含量无显著差异,油皮金桔的果籽率、抗坏血酸、金桔苷和总酚含量以及总抗氧化能力均显著高于脆皮金桔,而其出汁率、p H值、可溶性固形物、糖酸比、果糖、葡萄糖、蔗糖、苹果酸、草酸和芦丁含量均显著低于后者。本研究明确了两种金桔不同生长期的果实品质特性,为金桔果实的开发和利用提供了理论依据。     

Compositional changes during guava fruit ripening

Compositional changes of fruit pulp and peel during ripening of white- and pink-fleshed guava fruits were studied. The white and pink guava fruits exhibited a typical climacteric pattern of respiration. Fruit tissue firmness decreased progressively, in a similar manner, in both guava fruit types. Total soluble solids (TSS) and total sugars increased in pulp and peel of both guava types with decrease in flesh firmness. More increase in total sugars was observed after the climacteric peak of respiration. Reducing sugars and titratable acidity increased up to the full-ripe stage and then decreased. Ascorbic acid and phenolic compounds decreased continuously during ripening of the two types. The peel showed higher values of ascorbic acid, total protein and phenolic compounds than the plup. The white-fleshed guavas had higher levels of TSS, total sugars, reducing sugars. titratable acidity, phenolic compounds and ascorbic acid content then the pink-fleshed fruits.     

采前乙酰水杨酸与采后1-MCP处理对厚皮甜瓜冷藏品质及抗氧化能力的影响

以“玛瑙”厚皮甜瓜为试材,通过采前分别在幼果期（花后2 周）、膨大期（花后3 周）、网纹形成期（花后4 周）和采前2 d 4 个时期喷洒乙酰水杨酸和采后1-甲基环丙烯（1-methylcyclopropene,1-MCP）熏蒸,研究单独或复合处理对冷藏期间果实品质及抗氧化能力的影响。结果表明,采前乙酰水杨酸处理可有效抑制贮藏期间果实的质量损失率的增加,延缓果皮转黄,维持可溶性固形物和可滴定酸含量,提高总酚和类黄酮含量,提高抗氧化能力。1-MCP熏蒸能减少果实采后质量损失,维持硬度,增加抗坏血酸含量。复合处理在维持果实可溶性固形物和可滴定酸含量、提高总酚和类黄酮的含量方面表现出协同效应。由此表明,乙酰水杨酸和1-MCP处理对维持甜瓜果实采后品质的作用效果与抑制乙烯的产生有关,而果实抗氧化能力的提高则与促进苯丙烷代谢产物及抗坏血酸的积累相关。     

Camu-camu Myrciaria dubia (HBK) McVaugh: Chemical composition of fruit

Abstract : The chemical composition of the Peruvian camu-camu fruit Myrciaria dubia(HBK) McVaugh was analysed at three stages of maturity (immature, midripe and ripe). As fruit matured, levels of ascorbic and dehydroascorbic acids, reducing sugars (fructose and glucose were the major sugars), amino acids (serine, valine and leucine) and soluble solids increased. Citric acid was the major acid (from 19.8 up to 29.8 g kg^?1) and was responsible for the fruit's sour taste. Unlike citric acid, malic acid increased with maturation. Among the macronutrients, potassium was the most abundant mineral (711 mg kg^?1) and could be considered, like vitamin C, nutritionally significant. During maturation, the fruit pulp colour turned from yellow-green to pink, presumably due to the migration of anthocyanin pigments from the peel.     

Nitrogen and potassium requirements of tomato plants for the optimization of fruit quality and antioxidative capacity during storage

While nitrogen (N) and potassium (K) fertilizers are commonly used in tomato fields for increasing plant growth and productivity, concepts regarding the interactive effects of these elements on tomato fruit quality during storage are ambiguous. The interactive effects of potassium (0, 250 and 500 mg kg soil^??1) and nitrogen (0, 150 and 300 mg kg soil^??1) fertilizers were tested on tomato fruit size at harvest, and their quality was evaluated after 30 days of storage at 4 °C. Fruit mass, firmness, taste-related parameters, inorganic nutrients, bioactive compounds, and antioxidative capacity of the fruits were investigated after the storage period. Application of 250–500 mg K in combination with 150 mg N per kg soil improved fruit mass at harvest and reduced loss of mass during storage. By increasing the soil’s K supply, the fruits exhibited significant increases in their amount of potassium, TSS and TA contents, antioxidative capacity, concentrations of lycopene, phenolics and ascorbic acid. Nonetheless, increasing the soil’s K concentration reduced Ca concentration and firmness of the fruits. By increasing the N concentration in the soil, a trend of decline was observed in the fruits’ TSS, soluble phenolics, lycopene and ascorbic acid contents. However, higher amounts of N and TA contents were detected in fruits treated with 300 mg N kg soil^??1. N treatments did not affect the antioxidative capacity of the fruits. Accordingly, application of 250 mg K?+?150 mg N kg soil^??1 was suggested as the optimum treatment that could yield tomato fruits with high quality and that would also have improved storage capability.     

金丝小枣在生长成熟过程中理化特性的变化规律

本文研究了6个不同生长成熟期(S1~S6)金丝小枣果实的色泽、叶绿素、可溶性糖及其代谢酶活性、有机酸及氨基酸的动态变化,以明确其代谢规律。研究结果表明:枣果生长成熟过程中,叶绿素含量降低,枣果由绿变红;葡萄糖、果糖均逐步积累,而山梨醇含量逐渐降低,蔗糖则在生长发育初期未被检出,其积累主要发生在枣果成熟后期,且其含量最高,金丝小枣为蔗糖积累型果实,蔗糖磷酸合成酶是蔗糖积累的关键酶;金丝小枣为苹果酸型果实,苹果酸随枣果的成熟而积累,而柠檬酸含量先上升后降低;Pro和Asp在枣果成熟过程中被大量合成,是成熟枣果中最主要的两种氨基酸。全红枣的可溶性总糖、糖酸比以及游离氨基酸总量最高,可作为金丝小枣鲜食的最佳采收时期。     

桑葚果实不同发育期品质测定及其相关性分析

本研究对湛江地区7个桑葚品种青果期、转色期、成熟期三个时期桑葚果的单果重、可溶性固形物、可滴定酸含量及糖和有机酸组成和含量进行了测定,并进行了相关性分析。结果表明,在成熟过程中桑葚果实的可溶性固形物和糖含量呈增加的趋势,而酸则呈降低的趋势;在桑葚果实品种中检测出柠檬酸、苹果酸、奎宁酸、琥珀酸、酒石酸、酮戊二酸、抗坏血酸、草酸共8种有机酸,其中柠檬酸的含量最高,其在不同品种不同发育期含量为44.84%~80.86%,其次为奎宁酸和苹果酸;果糖和葡萄糖是桑葚重要的糖组成,其含量在成熟期的台湾长果桑的含量分别达到57.79 mg/g和66.72 mg/g,并且只有在台湾长果桑中检测到蔗糖;通过相关性分析,可滴定酸与可溶性固形物、果糖、葡萄糖、果重呈负相关,且可溶性固形物、果糖含量、葡萄糖含量三者之间呈极正相关。     

Antifungal activity of chitosan and its application to control post‐harvest quality and fungal rotting of Tankan citrus fruit (Citrus tankan Hayata)

In this study, the antifungal activity of chitosan A (MW = 92.1 kDa) and B (MW = 357.3 kDa), with 94.2% N‐deacetylation were examined at various concentrations against fungi including Penicillium digitatum, Penicillium italicum, Botrydiplodia lecanidion and Botrytis cinerea. The effectiveness of these chitosans to control the post‐harvest quality of Tankan fruit, a popular sub‐tropical citrus fruit, was investigated. It was found that chitosan, depending on type and concentration, caused 25.0–90.5% growth inhibition on test organisms after 5 days of cultivation at 24 °C. Chitosan treatment significantly reduced (P < 0.05) the percentage decay of Tankan fruit during storage at 24 °C. After 42 days of storage at 13 °C, chitosan‐coated Tankan fruits were firmer, exhibited less decay and weight loss, and showed higher titratable acidity, ascorbic acid, and total soluble solids than the control fruit. Weight loss of Tankan fruits decreased as the concentration of chitosan was increased. On the other hand, chitosan A, regardless of concentration tested, was found to be more effective in retaining the firmness, titratable acidity and water content, total solid content and ascorbic acid content of Tankan fruits than chitosan B. Copyright © 2006 Society of Chemical Industry     

猕猴桃及香梨冰点实验研究

水果冰点的确定是保证贮藏效果的前提。利用冻结法对猕猴桃和香梨的冰点进行测定,并分析冰点与营养成分之间的关系,包括还原糖、总糖、总酸及可溶性固形物。实验结果表明：猕猴桃的冰点变化较小,在－ 1.9～－ 2.6℃之间;香梨的冰点变化范围较大,在－ 1.4～－ 2.7℃之间。主要原因可能是猕猴桃的总酸度较高,降低了其他营养成分对冰点的影响;而香梨的酸度较小,冰点受到还原糖、总糖及可溶性固形物的影响较大,并随着它们质量分数的增大而降低。经实验数据所回归的猕猴桃及香梨冰点计算方程所计算的值与实验数据具有较好的吻合度。