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1.
 Four Spanish raspberry (Rubus idaeus L.) cultivars, Autumn Bliss, Heritage, Rubi, and Ceva, were studied in order to determine, qualitatively and quantitatively, both anthocyanins and vitamin C composition, owing to their significance as dietary compounds with antioxidant activity and also to the relation with color quality. Raspberry anthocyanin composition, determined by HPLC and GC-MS, was characteristic to each cultivar. The higher anthocyanin content expressed as cyanidin-3-glucoside was found in the late cultivars, Rubi (96.08 mg/100 g f.w.) and Ceva (122.88 mg/100 g f.w.). Three cultivars showed cyanidin-3-sophoroside (63.86–21.91 mg/100 g f.w.) and cyanidin-3-glucoside (25.12–14.00 mg/100 g f.w.) as the major pigments, while Autumn Bliss had a similar relative amount of cyanidin derivatives, cyanidin-3-rutinoside being the pigment in major concentration (10.53 mg/100 g f.w.). The vitamin C contents were determined by HPLC. The Rubi cultivar showed the highest amount of vitamin C (31.14 mg/100 g f.w.). The organic acids were determined by HPLC as fruit constituents related to color quality. Citric acid was the main non-volatile organic acid (90%) in all raspberry cultivars and the Rubi cultivar showed the highest total non-volatile organic acids content (2003 mg/100 g f.w.). Hunter color CIE values were also determined, showing that Rubi was the reddest raspberry cultivar. Received: 28 May 1998  相似文献   

2.
为探究红树莓叶片生长代谢过程中酚类物质含量与抗氧化酶活性的变化规律,以‘海尔特兹’和‘秋福’红树莓叶片为材料,对其总黄酮、7种酚类物质和3种抗氧化酶活性的变化规律进行比较分析。结果表明:从5月到12月,两品种红树莓上、中、下部叶片的鞣花酸含量、过氧化物酶(peroxidase,POD)活性在生长代谢过程中均呈双峰曲线,水杨酸含量在生长代谢过程中均呈下降趋势,阿魏酸、儿茶素、表儿茶素、芦丁、总黄酮含量在生长代谢过程中均呈单峰曲线,超氧化物歧化酶(superoxide dismutase,SOD)活性一直处于较高水平,过氧化氢酶(catalase,CAT)活性呈先下降再上升又下降的变化趋势;两品种红树莓上部叶片的咖啡酸含量均呈下降趋势,中部和下部叶片均呈单峰曲线。红树莓叶片中的酚类物质含量和抗氧化酶活性因生长代谢过程而异。其中,水杨酸、阿魏酸、鞣花酸、表儿茶素含量最高的时期依次是‘秋福’的5月份上部叶片、6月份上部叶片、7月份中部叶片、7月份上部叶片,依次为59.33 mg/100 g、158.18 mg/100 g、250.84 mg/g、350.04 mg/100 g;芦丁、咖啡酸、儿...  相似文献   

3.
The effects of preharvest methyl jasmonate (MJ) application on fruit quality, antioxidant activity and flavonoid content in blackberries (Rubus sp.) were determined. Anticancer activity against human lung A549 cells and HL-60 leukemia cells was also evaluated. Three blackberry cultivars (Chester Thornless, Hull Thornless and Triple Crown) were used in these experiments. Blackberries treated with MJ (0.01 and 0.1 mM) had higher soluble solids content, and lower titratable acids than untreated fruit as well as enhanced content of flavonoids and increased antioxidant capacity. Extracts of treated fruit showed enhanced inhibition of A549 cell and HL-60 cell proliferation and induced the apoptosis of HL-60 cells. Cultivar Hull Thornless had higher soluble solids and lower titratable acids compared to cv. Chester Thornless and Triple Crown. On the basis of fresh weight of fruit, Hull Thornless also had significantly higher anthocyanin, total phenolic content, antioxidant and antiproliferation activity than other two cultivars.  相似文献   

4.
In this work the correlation between the free radical‐scavenging capacity and bioactive compounds (anthocyanins, ellagic acid, total phenolics and vitamin C) in four Spanish raspberry cultivars (Heritage, Autumn Bliss, Zeva and Rubi) and Spanish wild blackberry as affected by freezing and frozen storage was evaluated. From this mathematical study a significant correlation was obtained between the radical‐scavenging capacity and the anthocyanin and total phenolic contents in both raspberry (r = 0.85 and 0.83 respectively) and blackberry (r = 0.84 and 0.68 respectively) fruits, but no correlation was found between this parameter and the ellagic acid and vitamin C contents. A key objective of this study was to select the raspberry cultivar most suitable for freezing preservation in terms of the stability of its health‐promoting constituents. A two‐dimensional principal component analysis (PCA) of the raspberry cultivars explained 82% of the total variance of the factors mentioned above. The early raspberry cultivars (Heritage and Autumn Bliss) showed a lower content of bioactive compounds and lower radical‐scavenging capacity, while the late cultivars (Zeva and Rubi) showed higher values, and these differences were clearly displayed by the PCA. © 2003 Society of Chemical Industry  相似文献   

5.
Forty‐two blueberry cultivars (thirty‐six Vaccinium ashei, three V. ashei derivative hybrids and three northern highbush standards) were evaluated for their antioxidant capacities and other fruit quality attributes over two growing seasons. Total anthocyanins, phenolic content and antioxidant capacities varied substantially among species and cultivars. ‘Early May’ (V. ashei) had the highest amounts of anthocyanins, phenolics and antioxidant capacity. Cultivars from V. ashei hybrid derivatives had lower mean antioxidant components than those from northern highbush standards or V. ashei. The antioxidant capacity, as well as total anthocyanins and phenolics, had significant cultivar × year interactions. Correlation coefficient between years for total anthocyanins, total phenolics and oxygen radical absorbance capacity were high with values of 0.86, 0.81 and 0.93, respectively. Similar interactions were observed for soluble solids content (SSC), sugar, titratable acid and organic acids among cultivars both within and across the growing seasons. Correlation coefficients between years for SSC, fructose, glucose and sucrose were 0.78, 0.71, 0.83 and 0.96, respectively. Fructose and glucose were detected as two major sugars with sucrose as a minor constituent. ‘Clara’ contained the highest amounts of SSC and sugars, while ‘Satilla’ had the lowest. In general, V. ashei cultivars had a higher mean SSC and sugar contents than did the hybrid derivatives or the northern highbush standards. Cultivars of V. ashei contained higher malic acid than citric acid, whereas in hybrid derivatives and northern highbush cultivars, citric acid was the predominant organic acid. The diversity in the amount of these fruit quality attributes and antioxidant capacities presents a great opportunity for genetic improvement of blueberries through breeding programmes. The objective of the study was to identify blueberry cultivars with high antioxidant activity and good fruit quality, so they can be used as parents for future blueberry breeding programmes to develop new cultivars with higher antioxidant activity.  相似文献   

6.
BACKGROUND: Tomatoes (Solanum lycopersicum L.) are widely consumed and well known for their health benefits, many of which have been associated with the high levels of antioxidants present in tomatoes. With a growing interest in local and organic foods, it would be helpful to determine whether farmers could naturally improve the quality and antioxidant content of tomatoes for sale in local markets. This study evaluated antioxidant properties, quality attributes, and yield for 10 tomato cultivars grown for 2 years using certified organic and conventional practices. RESULTS: Cultivar and year effects impacted (P < 0.05) all tests conducted, while growing method influenced (P < 0.05) yield, soluble solids content, ascorbic acid, and antioxidant radical scavenging capacity. Even when accounting for year‐to‐year variability, cultivars in the highest groups had 1.35‐ to 1.67‐fold higher antioxidant levels than cultivars in the lowest groups. ‘New Girl’, ‘Jet Star’, ‘Fantastic’, and ‘First Lady’ were always in the highest groups, while ‘Roma’ and ‘Early Girl’ consistently had the lowest antioxidant content. CONCLUSION: Compared to production practices and environmental effects of years that are generally beyond the control of small‐scale producers, choice of cultivar provides the simplest and most effective means of increasing antioxidant properties. Knowledge of tomato cultivars with naturally higher antioxidant levels could assist smaller‐scale producers to grow fruit that may provide a competitive advantage and the opportunity to capitalize on the increasing popularity of locally grown, high‐quality fresh produce. Copyright © 2010 Society of Chemical Industry  相似文献   

7.
Seven primocane fall-bearing raspberry (Rubus idaeus L.) cultivars, Nova (red), Dinkum (red), Heritage (red), Autumn Britten (red), Josephine, Anne (yellow), Fall Gold (yellow) were analysed for potential health promoting properties including their inhibitory effect on starch and fat digestive enzymes, antioxidant activities, and phenolic composition. The tested raspberry extracts showed no detectable inhibition of pancreatic α-amylase and lipase. However, all the extracts exhibited potent inhibition of α-glucosidase with IC50 from 16.8 to 34.2 μg/mL. Four phenolic compounds, ellagic acid, cyanidin-diglucoside, pelargonidin-3-rutinoside, and catechin were identified as the active α-glucosidase inhibitors. The raspberry extracts also possessed significant antioxidant activities with oxygen radical absorbance capacities (ORAC) ranging from 136.7 to 205.2 μmol Trolox equivalents (TE)/g dry weight fruit and DPPH radical scavenging activities from 305 to 351 μmol TE/g. The total phenolic content of raspberry cultivars varied significantly from 40.9 to 98.5 mg of gallic acid equivalents/g dry weight. The anthocyanin content varied widely from 0.1 to 9.5 mg cyanidin 3-glucoside equivalents/g. Nine phenolic acids were quantified in raspberries and their total amounts varied from 157.3 to 713.5 μg/g. The enzyme inhibition and antioxidant properties of raspberry cultivars were not correlated with their total phenolic, anthocyanin, and phenolic acid content. Overall, ‘Dinkum’ and ‘Josephine’ raspberry varieties possess higher total phenolic content, ORAC, DPPH radical scavenging activity, and α-glucosidase inhibitory activity than other five cultivars.  相似文献   

8.
不同解冻方式对软儿梨果实品质与抗氧化物质含量的影响   总被引:1,自引:0,他引:1  
冷冻和解冻是产区消费者传统上消费软儿梨的两个必要步骤,外源乙烯可以加速呼吸跃变型果实的后熟进 程。本实验以自然后熟和乙烯利催熟的软儿梨为材料,研究了传统的空气解冻和水浴解冻对解冻后果实品质和酚类 物质含量的影响。结果表明:对于自然后熟的软儿梨,空气解冻组果实的可滴定酸含量、可溶性固形物含量、固酸 比均显著高于水浴解冻组;同时使自然后熟组果实保留了更多的VC,降低了石细胞含量。空气解冻较水浴解冻降 低了乙烯利处理组果实的可滴定酸和可溶性固形物含量,但对其固酸比、VC和石细胞含量无显著影响。空气解冻 和水浴解冻均对自然后熟组果实的总酚含量无显著影响,但乙烯利处理组果实的总酚含量上升;两种解冻方式对几 种主要酚类物质的影响表现各异,但相似的是解冻后果实均不能测出绿原酸和阿魏酸。不同解冻方式对果实不同的 抗氧化指标影响各异,但从抗氧化能力综合指数来评价,不同工艺点的果实抗氧化能力依次为:水浴解冻>空气解 冻>后熟,在后熟和解冻中均为:乙烯利处理组果实>自然后熟组果实。  相似文献   

9.
The aim of this study was to evaluate the effect of the postharvest treatment by 1-methylcyclopropene (1-MCP) and storage time on the apple physicochemically quality. The effects of apple storage during 6 months on basic parameters such as dry weight, total soluble solids and titratable acidity, composition of phenolics, antioxidant activity and sensory evaluation were studied to evaluate the potential applicability of long-time stored apples for consumption and processing. Long-time storage of apples resulted in a higher dry matter but decreases total soluble solids and titratable acidity in all examined cultivars (cv.) of apples. The total phenolics determined by HPLC in fresh apples ranged from 1,243 mg in ‘Idared’ cv. to 1,435 mg/kg in ‘Shampion’ cv. During storage, the decrease of polyphenolic content has been observed, in ‘Shampion’ cv., it was higher than in ‘Idared’ cv. Similar effects were observed for antioxidant activity. Comparing quality of fruits just after harvest, it was found that cultivar affects most of the investigated sensory attributes with the exception of ripe apple smell, crispness, crunchiness and the overall texture score. In general, ‘Shampion’ cv. apples got higher ranks for sweetness, taste and the overall quality, whereas ‘Idared’ cv. were perceived as sourer, which is in arrangement with instrumental measurements. The results of presented study demonstrate that apples after storage, especially ‘Shampion’ cv., can be a valuable sensory attributes for food product and consumption. This study indicates that the use of 1-MCP treatment in long-term storage of apples is promising for maintaining the eating quality of fruits, however, in some extent may affect their antioxidant compounds content.  相似文献   

10.
BACKGROUND: Modern consumers are increasingly interested in their personal health and expect the food they purchase to be tasty and attractive while being safe and healthful. The aim of this study was to determine the commercial quality, characterise the antioxidant capacity and quantify the major bioactive compounds of 12 cultivars of loquat fruits in order to establish a database for utilising these germplasm resources. RESULTS: Of the 12 cultivars, ‘Guanyu’ produced the biggest fruits, while ‘Tianzhong’ and ‘Bingtangzhong’ had the highest soluble solids content but the lowest titratable acidity. ‘Taipinghong’ was reddest in colour. Sucrose, fructose, glucose and sorbitol were the major sugars in loquat fruits, with the highest total sugar content being observed in ‘Bingtangzhong’ and ‘Tianzhong’. Phenolics and flavonoids were the main bioactive compounds and were abundant in ‘Tianzhong’ and ‘Zhaozhong’. ‘Taipinghong’ had the highest total carotenoid content, while ‘Qingzhong’ had the highest vitamin C content. ‘Tianzhong’, ‘Bingtangzhong’ and ‘Ninghaibai’ showed higher antioxidant activity than the other cultivars, as measured by assays of 1,1‐diphenyl‐2‐picrylhydrazyl (DPPH) and 2,2‐azino‐bis(3‐ethylbenzthiozoline‐6‐sulfonic acid) (ABTS) scavenging and ferric‐reducing/antioxidant power (FRAP). CONCLUSION: Commercial fruit quality, major bioactive compound content and antioxidant capacity varied greatly among the 12 cultivars. ‘Bingtangzhong’ and ‘Tianzhong’ were the highest‐ranking cultivars based on their good commercial quality and high nutritional value. The loquat fruits with higher total phenolic and flavonoid contents also had clearly higher antioxidant capacities. Copyright © 2011 Society of Chemical Industry  相似文献   

11.
以新疆吐鲁番地区种植的8个甜瓜品种(纳斯蜜、花玫、风味5号、风味8号、西州密17号、西州密25号、比谢克辛、俊秀)的成熟果实为试材,通过测定主要的营养品质指标及功能活性指标,对甜瓜果实品质进行比较及综合评价。结果表明,8个不同品种甜瓜果实品质之间有较为明显的差异,纳斯蜜的维生素C、可溶性固形物、可溶性蛋白质、蔗糖、果糖、葡萄糖的含量较高;花玫的果肉较硬,且厚度宽、果形指数高;风味系列的两种甜瓜类黄酮含量高、DPPH、ABTS自由基清除率较其他甜瓜大;俊秀的单果重最高,维生素C含量最低;其他品种甜瓜的含量处于平均水平。主成分分析结果表明,可将评价甜瓜果实品质的指标用4个因子表示,可溶性固形物、维生素C、总酚、ABTS自由基清除率、柠檬酸、葡萄糖、果糖、葡萄糖和果形指数的含量可作为其营养价值评价的重要指标;通过聚类分析,将8个不同品种的甜瓜分为4大类,第1类为‘风味8号’和‘风味5号’,具有酸甜风味;第2类为‘西州密17号’、‘西州密25号’、‘比谢克辛’和‘纳斯蜜’,具有较高的营养价值;第3类为‘花玫’,果形指数最好;第4类为‘俊秀’,单果重与其他品种比较具有明显优势。综合评价显示‘纳斯蜜’果实品质最优,‘西州密25号’、‘花玫’、‘风味5号’和‘比谢克辛’较优,其余品种品质较差。  相似文献   

12.
In this study, we investigated the effects of fruit ripening stage on the physico-chemical properties and nutritional contents of three greenhouse grown tomato cultivars (‘Monika’, ‘Isabella’ and ‘Cherry’). Significant changes (p?≤?0.05) occurred in fruit colour, total soluble solids, protein, fibre, ascorbic acid (vitamin C) and lycopene content at different stages of ripening. ‘Cherry’ tomato contained significantly (p?≤?0.05) higher total soluble sugar and several nutrients including fibre. However, the plum-type tomato cultivars (‘Monika’ and ‘Isabella’) contained higher vitamin C and lycopene than ‘Cherry’ tomato. In all tomato cultivars, it was found that up to 50% of final lycopene content occurred during the final phase (from red to deep red colour) of fruit ripening.  相似文献   

13.
本研究拟在初步揭示悬钩子属浆果不同发育时期叶片中鞣花酸的变化规律。以黑莓、树莓及杂交类型共21个品种不同时期叶片为试材,用超声辅助溶剂提取法提取叶片中鞣花酸,用紫外分光光度法快速检测鞣花酸含量。在此基础上,选取其中5个品种分析评价了叶片抗氧化能力、抗氧化物质含量及糖类物质含量与鞣花酸含量的关系。结果表明,黑莓、树莓鞣花酸在嫩叶中含量较高,随着叶片的发育和衰老呈下降趋势,以黑莓‘宝森’嫩叶鞣花酸含量最高达39.622 mg/g,以树莓‘哈瑞泰兹’老叶中鞣花酸含量最低为7.649 mg/g。进而分析5个品种叶片的抗氧化能力及抗氧化物质含量,发现其与鞣花酸含量变化趋势相似,而叶片中糖类物质含量与鞣花酸含量变化呈负相关。研究结果为黑莓、树莓叶片中鞣花酸的功能研究及进一步开发利用提供部分基础理论依据。  相似文献   

14.
Mature ‘Amber Jewel’ Japanese plum fruit were stored at 0 or 5 °C for 3 and 6 weeks to investigate their effects on ethylene (C2H4) biosynthesis during ripening at ambient temperature in the development of chilling injury (CI) and fruit quality. CI (internal breakdown and browning) and fruit softening were higher during ripening, in the fruit stored at 5 °C than 0 °C, irrespective of storage period (SP). C2H4 production and activities of 1‐aminocyclopropane‐1‐carboxylic acid synthase (ACS) and 1‐aminocyclopropane‐1‐carboxylic acid oxidase (ACO) enzymes, and 1‐aminocyclopropane‐1‐carboxylic acid (ACC) content were higher during ripening in fruit stored at 5 °C than 0 °C. The fruit stored at 5 °C also exhibited higher respiration rate and higher soluble solids concentration/titratable acidity ratio. In conclusion, increase in storage temperature and SP elevates the activities of ACS and ACO enzymes and consequently C2H4 production which leads to the development of CI in plum fruit with advancement of ripening.  相似文献   

15.
针对‘檀香’橄榄果实冷藏期间易发生冷害现象,本实验研究了7 个采收期(Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ、Ⅵ、Ⅶ)对(2±1)℃、相对湿度85%~90%条件下冷藏橄榄果实冷害的影响。定期测定贮藏期间橄榄果实冷害指数、果皮褐变指数、果实好果率和质量损失率、果实呼吸强度和细胞膜相对渗透率、果实表面色度角、果皮叶绿素含量、果肉可溶性固形物、可滴定酸、可溶性总糖和还原糖含量的变化。结果表明:与采收期Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅵ、Ⅶ相比,采收期Ⅴ能保持冷藏橄榄果实较低的冷害指数、果皮褐变指数、果实质量损失率和较高的好果率,降低果实呼吸强度和呼吸峰值,延缓果实细胞膜相对渗透率升高,保持中后期较高的果实表面色度角、果皮叶绿素含量、果肉可溶性固形物、可滴定酸、可溶性总糖和还原糖含量。因此认为,采收期Ⅴ可作为减轻冷藏‘檀香’橄榄果实冷害发生的适宜采收成熟度。  相似文献   

16.
以4 个品种(‘海沃德’‘徐香’‘华优’‘亚特’)猕猴桃为试材,采用剂量分别为0.4、0.8、1.2 kGy的高能电子束辐照处理,于0~1 ℃、相对湿度90%~95%条件下贮藏,每15 d取样一次,测定电子束辐照处理对果实冷藏期硬度、质量损失率、可溶性固形物质量分数、可滴定酸质量分数、VC含量等品质指标的影响,探究电子束辐照对猕猴桃贮藏品质的影响,为猕猴桃采后保鲜技术提供理论依据。结果表明,电子束辐照处理对维持猕猴桃的贮藏品质有一定积极作用。适宜剂量电子束辐照能抑制猕猴桃贮藏期间果实的质量损失,延缓可滴定酸质量分数的下降,提高类黄酮含量,在贮藏前期提升多酚含量,但硬度、VC含量经辐照后有所降低,且可溶性固形物质量分数升高。相比其他剂量,0.8 kGy电子束辐照能够较好地延缓猕猴桃可溶性固形物质量分数升高和可滴定酸含量降低,提高多酚和类黄酮的含量。整体来看,4 个品种中‘海沃德’‘亚特’更加耐受电子束辐照,且0.4、0.8 kGy剂量的电子束辐照对‘海沃德’‘亚特’的采后贮藏保鲜效果较好,推荐0.4、0.8 kGy为‘海沃德’‘亚特’的采后保鲜辐照剂量。结论:适宜剂量的电子束辐照可以作为提升猕猴桃保鲜效果的有效手段。  相似文献   

17.
A range of blackberry genotypes harvested in different seasons and regions in Mexico (Michoacan) and in the United States (Pacific Northwest) were collected to determine their antioxidant capacity using oxygen radical absorbance capacity (ORAC) and ferric reducing antioxidant power (FRAP) assays. Total acidity, ascorbic acid, soluble solids, total phenols, and total anthocyanins, as well as the correlation between all these parameters, were determined for all treatments. Total acidity ranged from 4.22% in wild blackberry from Patzcuaro, Mexico, to 1.02% in ‘Evergreen’ from Woodburn, Oreg. These treatments were also the outliers in terms of ascorbic acid content. Cultivar ‘Brazos’ did not exhibit any significant differences in acidity or ascorbic acid as a consequence of the geographic origin or harvest season. The highest concentration of soluble solids was recorded for ‘Evergreen’ from Woodburn and relatively low soluble solids levels were recorded for all the Mexican treatments. Wild blackberry from Patzcuaro exhibited the highest values for ORAC, FRAP, total phenolic and anthocyanin content. Other relatively high antioxidant capacity values were detected for ‘Marion’ and ‘Evergreen’, both produced in Oregon. Different cultivars grown in the same region/season consistently showed differences in antioxidant capacity. There was little effect of harvest season on phenolic levels. We conclude that levels of total acidity, ascorbic acid, soluble solids, antioxidant capacity, and polyphenols mainly depended on the genotype and not on the climate or the season. ORAC and FRAP values were both highly correlated with each other, and with total phenols and anthocyanin content.  相似文献   

18.
Mid-season peach (Primus persica (L.) Batsch cv Majestic) fruit of five maturity stages, from red suture to red, full soft, were subjected to warming treatments before and during storage at 5C. Intermittent warming and delayed storage accelerated softening in red suture, half and full red hard fruit. The treatment effect was greater with less mature fruit. Treatment had no effect on soluble solids concentration, total phenolics, or titratable acidity.‘Majestic’ peaches could be held at 5C up to four weeks if harvested at the half red or full red hard stage and held at room temperature for 24 h before storage.  相似文献   

19.
Treatment of mango (Mangifera indica cv ‘Kent’) fruits with methyl jasmonate (MJ) vapour for 20 h at 20 °C reduced chilling injury (CI) symptoms and enhanced skin colour development. MJ at 10?4 M was the most effective concentration for reducing CI and decay in fruits stored at 5 °C followed by 7 days at 20 °C (shelf‐life period). The use of 10?5 M MJ enhanced yellow and red colour development of mangoes stored at 20 °C. These fruits possessed higher L*, a* and b* values than untreated fruits and those treated with 10?4 M MJ. Ripening processes were inhibited by cold storage (5 °C) in control fruits. After cold storage and shelf‐life period, fruits treated with 10?5 M MJ ripened normally and contained the highest total soluble solids (TSS). These fruits also maintained higher sugar and organic acid levels than fruits subjected to other treatments. We concluded that MJ treatment could be used to reduce decay and CI symptoms and also to improve colour development of mango fruits without adversely affecting quality. © 2001 Society of Chemical Industry  相似文献   

20.
BackgroundPears due to low acidity are a suitable raw material for the production of multifruit nectars thus it is justified to determine the chemical composition and investigate the effect of cultivar and fruit maturity on juices quality.MethodsJuices from ‘Alexander Lucas’ and ‘Conference’ cultivars were produced after harvest and after 3 months of pears storage.ResultsAverage yield of clear juices was 76.4% for ‘Conference’ cultivar and 74.3% for ‘Alexander Lucas’. In the case of cloudy juices, the yield was lower by about 3%. Processing of ‘Conference’ cv. from stored fruit resulted in yield decrease compared to fruits after harvest; this was not in case of ‘Alexander Lucas’ in 2008, where juices produced from stored fruits were characterized by a higher yield compared to fresh fruit.Total solids content in clear juices was 125–135 g/L and 135–141 g/L for cloudy juices. ABTS●+ and total phenolics analysis showed that cloudy juices were characterized by a higher antioxidant activity and phenolics content than the clear ones.ConclusionPear storage, on the contrary to apples, does not decrease their suitability for cloudy juice production. Cloudy juices as a rule have higher antioxidant activity than the clear ones.  相似文献   

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