首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
‘Limoncella’ is a variety of apple traditionally cultivated in south-central Italy since ancient Roman times. The relationship between phenolic composition and antioxidant activity of apple peel and flesh was investigated. Apple extracts analysed by high-performance liquid chromatography, showed that compared with flesh, peel was richer in all the quantified phenols. The most abundant polyphenols were the flavanols catechin and epicatechin, and the chalcones phloridzin and phloretin xyloglucoside.  相似文献   

2.
《食品工业科技》2013,(03):339-341
以无花果果实为试材,研究了1-甲基环丙烯(1-Methlcyclopropene)对果实贮藏品质及采后生理指标的影响。在室温(20±0.5)℃下采用浓度为0、1.0、1.5、2.0μL/L的1-MCP对无花果果实处理24h,处理后的果实在低温(0±0.5)℃条件下贮藏。研究结果表明:与对照果实相比,1-MCP处理延缓了果实硬度和VC含量的下降,抑制了果实的呼吸强度,减少了乙烯释放量,从而保持了果实的贮藏品质,延缓了无花果成熟与衰老进程,延长了贮藏时间,其中以1.5μL/L处理的效果较好。   相似文献   

3.
1-MCP处理对货架期韭薹品质的影响   总被引:4,自引:0,他引:4  
以福建薹韭为试材,研究了0.5和1.0μL/L1-MCP处理对采后韭薹在货架期间(20±0.5℃)品质变化的影响。研究发现,货架期间韭薹品质变化迅速,货架6d后商品价值明显下降,9d时已丧失商品价值。1-MCP处理延缓了韭薹品质的劣变,尤其在货架的前6d提高了货架期的质量。0.5μL/L1-MCP处理在减少韭薹薹苞开放、薹苞增重,延缓韭薹叶绿素和可溶性蛋白的降解方面效果明显,更适合用于提高韭薹的货架品质。  相似文献   

4.
以阿克苏红富士苹果为试材,对三个采收期果实进行1-MCP熏蒸处理,通过测定贮藏过程中果实硬度、可滴定酸含量、VC含量、可溶性固形物含量、失重率等指标,研究1-MCP处理对不同采收期果实低温贮藏下果实品质与生理变化的影响。结果表明:使用1.0μL/L的1-MCP在常温下处理富士苹果24 h,在低温贮藏期间果实呼吸高峰的出现推迟了30 d;至贮藏结束,不同采收期的果实处理组失重率平均低于对照组10%,处理组硬度平均高于对照组0.33 kg·cm-2,处理组可滴定酸含量平均高于对照组0.16%。1-MCP处理对不同采收期果实在贮藏期间品质的影响差异显著,根据贮藏过程中果实品质的变化情况,中期采摘果实(本文为11月1日)1-MCP处理效果较好,贮藏150 d后果实硬度≥8.66kg·cm-2,可溶性固形物含量≥14.79%。   相似文献   

5.
‘Sikitita’ is a new olive cultivar developed in Spain by crossing the cultivars ‘Picual’ and ‘Arbequina’. The phenolic fraction of olive leaves (Olea europaea L.), is purported to have good anti-oxidative properties which help to prevent several health problems. To our knowledge, no studies are available on the phenolic fraction of ‘Sikitita’ olive leaves or any other new cultivar developed from breeding. Thus, the identification and quantification of the phenolic fraction of ‘Sikitita’ olive leaves by HPLC-DAD-MS were studied and compared with those of its parent cultivars. The three cultivars were grown under the same agronomic and environmental conditions in the same orchard. The quantification was performed using HPLC-DAD, whereas qualitative data were acquired using HPLC-MS. It was thus possible to identify 30 different compounds, two of which have been tentatively characterized for the first time in olive leaves of Spanish cultivars. Significant differences between cultivars were observed for almost all the compounds. Results for ‘Sikitita’ olive leaves presented a higher degree of similarity with respect to ‘Picual’ than to ‘Arbequina’. Further work will monitor the time course of phenolic compounds over the growth period.  相似文献   

6.
李玉  秦文  李杰  郭元照 《食品与机械》2015,31(4):138-143
为探讨保鲜方式对佛手瓜采后品质变化的影响,以绿皮无刺佛手瓜为试材,在温度(9±1)℃、湿度90%~95%的贮藏条件下,分别采用气调贮藏(5%O2+5%CO2+90%N2)、臭氧(5mg/L)和1-MCP(900nL/L)3种保鲜方式进行佛手瓜贮藏试验,测定和分析贮藏过程中佛手瓜品质和生理指标的变化。结果表明:与对照组相比,贮藏期间3个处理组果实品质相对较好;其中经1-MCP处理后的果实呼吸跃变高峰比其他组(第15天)推迟15d出现,其在贮藏末期呼吸强度最低为4.27mg CO2/(kg·h),叶绿素和Vc含量分别为0.27mg/kg和6.59mg/100g,为所有处理组中最高;过氧化氢酶(CAT)、过氧化物酶(POD)和超氧化物歧化酶(SOD)等指标均优于其他处理组和对照组。  相似文献   

7.
Polyphenol content, antioxidant activity, reducing power, colour and changes during storage over nine months in bottles and after accelerated browning were studied in selected Hellenic varietal white wines. The following phenolic compounds were identified in the wines: Caftaric, coutaric, fertaric, ferulic, caffeic, p-coumaric and gallic acids, (+)-catechin and (−)-epicatechin. The results showed that the contents of most of the phenols diminished with time, with the exception of caffeic, ferulic and p-coumaric acids. Antioxidant activity increased with storage whereas reducing power remained significantly unaffected. Accelerated browning did not significantly alter the concentrations of tartaric acid esters but it increased the concentrations of the hydroxycinnamic and gallic acids. (+)-Catechin concentration was not affected while (−)-epicatechin decreased. Antioxidant activity did not show any significant change but reducing power was reduced after the end of the browning test. As for the absorbance at 420 nm, it remained unchanged during storage, but it was significantly increased after accelerated browning.  相似文献   

8.
The effect of 1-methylcyclopropene (1-MCP) on postharvest characters, antioxidants and glucosinolate contents in bolting stems of Chinese kale (Brassica alboglabra Bailey) was investigated. Chinese kale was treated with air (control) and 10 μl l−1 of 1-MCP for 24 h, followed by storage for up to seven days at 20 °C. 1-MCP treatment obviously extended the shelf life, delayed weight loss and decreased the rate of softening, chlorophyll degradation and changes in hue angle. In addition, ethylene production was suppressed and the respiration rate declined. Moreover, 1-MCP treatment postponed the decrease of ascorbic acid, carotenoids and glucosinolates. 1-MCP treatment of bolting stems also delayed the accumulation of total phenolics, and maintained a high level of antioxidant capacity. These results demonstrate that 1-MCP treatment is a good practice for extending shelf life, maintaining the appearance and nutrient value, and reducing the loss of health-promoting compounds, particularly antioxidants and glucosinolates in the Chinese kale.  相似文献   

9.
1-MCP对不同采收期黄冠梨褐心病及贮藏品质的影响   总被引:5,自引:0,他引:5  
以黄冠梨果实为试材,研究1-甲基环丙烯(1-MCP)处理对不同采收期黄冠梨常温贮藏褐心病发生的控制效果及相关品质指标变化。结果表明:1-MCP处理能显著抑制黄冠梨常温贮藏期间果心褐变的发生,降低果实贮藏期间的呼吸速率,抑制乙烯释放速率,推迟乙烯释放高峰出现的时间,保持较好的果实硬度,延缓果实可滴定酸、可溶性固形物含量的下降,较好地保持黄冠梨果实的品质,保鲜效果显著。且1-MCP对黄冠梨褐心的控制效果与成熟度密切相关。  相似文献   

10.
为寻找新型、无硫的鲜食葡萄保鲜方法,以新疆木纳格葡萄为试材,研究0.5、1.0和1.5 μL/L的1-MCP熏蒸处理对其在常温(25±0.5) ℃和冷藏(0~3) ℃贮藏期间果实的主要品质、生理指标及其作用效果的影响。结果表明:1-MCP熏蒸处理能在不同程度上降低常温贮藏条件下以及冷藏条件下葡萄的脱粒率、腐烂率、果穗失重率和果梗褐变,保持葡萄的硬度、可溶性固形物、VC含量、可溶性糖含量以及可滴定酸含量。室温贮藏结束时,1.0 μL/L浓度1-MCP处理的葡萄可溶性糖含量为10.18%,比对照组高出29.36%,可溶性固形物比对照组高出20.65%,而失重率却比对照组低34.85%。冷藏贮藏结束时,1.0 μL/L浓度1-MCP处理的葡萄腐烂率为26.13%,比对照组低30.49%,而VC含量比对照组高出34.38%。0.5 μL/L和1.5 μL/L的1-MCP处理对维持果实品质也有一定的作用,但是效果均不如1.0 μL/L处理的果实明显。综上所述,1.0 μL/L浓度的1-MCP处理的葡萄腐烂率最低,果实的外在品质和内在品质下降幅度最小,保鲜效果最好。  相似文献   

11.
Yun Deng  Ying Wu 《LWT》2006,39(6):584-590
This research studied the physiological responses and quality attributes of Kyoho grapes (Vitis vinifera X V. labrusca) to controlled atmosphere storage. The grapes were stored for up to 60 days in 95% relative humidity with four different conditions, 4% O2+9% CO2, 4% O2+30% CO2, 80% O2, and air, as control. The examined physiological responses and quality attributes included polyphenol oxidase (PPO) activity, ethanol concentration, fruit detachment force (FDF), firmness, color, soluble solid content (SSC), titratable acidity (TA), ascorbic acid concentration (Vc), and sensory quality. PPO activity, FDF drop and decay incidence when stored in 4% O2+30% CO2 were more effectively controlled, but unacceptable alcoholic flavor and browning were detected after 45 days, compared with those stored in 4% O2+9% CO2 or 80% O2. The fruits kept in 4% O2+9% CO2 or 80% O2 had good quality during 60 days of storage. The results suggested that high O2 atmosphere exhibited a potential for maintaining the quality of ‘Kyoho’ grapes during long-term storage.  相似文献   

12.
Effect of processing on buckwheat phenolics and antioxidant activity   总被引:2,自引:0,他引:2  
The effect of processing on functional compounds in buckwheat was investigated. Extractions of buckwheat flour were carried out before and after roasting or extrusion. Folin–Ciocalteu assays indicated that processing did not cause any change in total phenolic content in buckwheat flour. Roasted (200 °C, 10 min) dark buckwheat flour exhibited an increase in non-polar compounds as well as polar compounds whereas extrusion exhibited increase only in polar compounds. Antioxidant activity test (DPPH) showed that roasting at 200 °C for 10 min decreased the antioxidant activity slightly whereas extrusion (170 °C) did not cause any change. The results suggest that processing conditions can be optimized to retain the health promoting compounds in buckwheat products.  相似文献   

13.
为探讨1-甲基环丙烯(1-methylcyclopropene,1-MCP)处理对‘粉红女士’苹果采后生理特性及其品质的影响。用1.0 μL/L的1-MCP处理‘粉红女士’苹果24 h,以不处理为对照,20℃条件下贮藏,定期测定贮藏期间的主要品质及相关生理指标。结果表明:1-MCP处理可保持苹果贮藏过程中的硬度、可滴定酸含量,延缓果皮油腻化的发生,显著抑制果实的呼吸强度和乙烯释放速率,推迟果实过氧化氢酶、过氧化物酶两种酶活性峰值的出现,并在一定程度上提高了超氧化物歧化酶和过氧化氢酶的活性,有效抑制丙二醛含量的积累。因此,1-MCP处理可较好地调控‘粉红女士’苹果的相关生理代谢,改善果实的贮藏品质,从而有效延缓果实采后的成熟衰老进程。  相似文献   

14.
以甘肃天水‘花牛’苹果为原料,通过测定其果实硬度、VC含量、有机酸质量分数、可溶固形物质量分数及腐烂率等指标,研究低温贮藏及1-甲基环丙烯(1-methylcyclopropene,1-MCP)处理对‘花牛’苹果果实品质与生理变化的影响。结果表明:低温处理的保鲜作用优于1-MCP处理;低温及1-MCP处理均能显著减缓果实硬度及VC含量下降,降低腐烂率,能较好地维持外观色泽与口感,并在一定程度上稳定了有机酸质量分数变化,但对可溶固形物质量分数的影响极小。  相似文献   

15.
The polyphenolic components of Idared and Shampion apple purées were determined by HPLC; chlorogenic acid was the most abundant acid (20.0 mg/100 g in microwaved Idared); other polyphenols identified in high concentrations included (−)-epicatechin, procyanidin B1 and B2; quercetin and cyanidin glycosides were found in minor concentrations. The Shampion purées had higher total phenolics (142 mg/100 g) and procyanidin B2 concentrations (17.3 mg/100 g) than the Idared ones, and polymeric procyanidins represented 41% of all polyphenols. Antioxidant capacities of the samples, determined by spectrophotometric methods and EPR spectroscopy, correlated well with the concentration of polyphenols. The antioxidant properties could be better represented by EPR than by UV–vis measurements. The latter require transparent (clear) samples whereas EPR can be a method of choice in the assessment of radical-scavenging activity of dense and cloudy apple purées. Our results support the putative high antioxidant value of apple purées and define their capacity in terms of the major constituents. Apple purées are a rich source of natural antioxidants, especially of chlorogenic acid and procyanidins.  相似文献   

16.
Ruyi Wu  James A. Kennedy  Yanyun Zhao 《LWT》2010,43(8):1253-1264
The effects of refrigerated storage at 2 °C and 95% RH and processing treatments on the bioactive compounds and antioxidant capacities of ‘Marion’ and ‘Evergreen’ blackberries were investigated. During refrigerated storage, total phenolics (TPC), total monomeric anthocyanins (ACY), and radical scavenging activity (RSA) fluctuated in ‘Marion’, but TPC and ACY continuously declined in ‘Evergreen’. Oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) decreased by 20% and increased by 19% in ‘Evergreen’, respectively after 7-d refrigerated storage, while no changes (P > 0.05) in ‘Marion’ were observed. Compared with frozen samples, freeze-dried ‘Evergreen’ had higher TPC (21%), ACY (5.5%), and RSA (14%), while hot-air dried “Marion” had lower ACY (56%), ORAC (37%), and FRAP (27%) and hot-air dried ‘Evergreen’ had lower TPC (37%), ACY (84%), and RSA (13%). ORAC and FRAP in canned ‘Marion’ was 21-61% lower than that of frozen samples. Jam also had lower TPC and ACY (67-84%), RSA (˜80%), and ORAC and FRAP (65-77%) values than frozen ones in both varieties (P < 0.05). The 6-mo post-process room storage had little effect on the bioactive compounds of frozen and freeze dried samples, but reduced ACY in hot-air dried, canned, and jam samples, and antioxidant capacities of all samples (P < 0.05).  相似文献   

17.
以鸭梨果实为试材,采用1.0μL/L的1-MCP处理果实,研究了1-MCP处理对常温贮藏鸭梨果实品质及生理指标的影响。研究结果表明:与对照相比,1-MCP处理显著(p<0.05)降低了鸭梨常温贮藏的呼吸强度和乙烯释放量,推迟了呼吸和乙烯高峰的出现,抑制了果实PPO酶活性,延缓了果实可溶性固形物含量和硬度的下降。1-MCP处理较好地提高了鸭梨常温贮藏的好果率,并延长了贮藏时间。   相似文献   

18.
This study investigated the effect of adding sour cherry pulp into yoghurt on its physicochemical properties, phenolic content, antioxidant activity and sensory characteristics. Sour cherry pulp was added at 0%, 8%, 12% and 16% into the yoghurt, and measures were checked through 14 days cold storage. The increasing sour cherry pulp concentration in yoghurt resulted in increasing pH and whey separation, whereas the values of the other parameters, total solid, fat, protein, ash, titratable acidity and viscosity decreased. During storage, total phenolic contents and antioxidant activity in yoghurts ranged from 20 to 81 μg gallic acid equivalent per mg of sample and from 48% to 86%, respectively.  相似文献   

19.
山东酿酒葡萄发展技术层面需要实现两个突破   总被引:1,自引:0,他引:1  
葡萄酒产业发展的基础是葡萄基地建设,而葡萄基地建设的技术前提是对园区风土条件与具体葡萄品种生物特性的了解、掌握。具体地区的风土条件包括:地形、地貌、地质、土壤、光照、气温、降雨等,是葡萄生产的环境要素。  相似文献   

20.
The purpose of this research was to model the kinetics of adsorption of 1-methylcyclopropene (1-MCP) in apple fruit and non-target solid materials found in apple storage rooms. The process was described by Fick’s second law of diffusion of the gas through the pores of the material coupled with adsorption kinetics of the gas on the material’s binding sites. A finite element formulation of the model, describing the diffusion and adsorption mechanisms separately, was first developed. The values of the relevant parameters were estimated based on headspace measurements of the decrease of 1-MCP in jars containing the different materials. The headspace concentration of 1-MCP was measured using gas chromatography. Apple fruit (Golden Delicious and Jonagold) and the following bin construction materials were investigated: high density polyethylene (HDPE), oak, poplar wood and card lining. The range in the magnitude of the diffusion coefficient, adsorption coefficient, and concentration of active sites in the various solids was 10,000-, 8-, and 30-fold, respectively.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号