Antioxidant Bioactive Compounds in Selected Industrial Processing and Fresh Consumption Tomato Cultivars

Four selected fresh consumption tomato varieties, harvested at different ripening stages (green, breaker, pink, red) and five industrial processing tomato varieties, harvested at red ripe stage, were analysed for lycopene and its isomers, β-carotene, total and individual phenolics, vitamin C and hydrophilic antioxidant activity. Tomato variety and ripening stage significantly affected carotenoids, total phenolic compounds and hydrophilic antioxidant activity when fresh consumption tomatoes were compared. The average of total lycopene content at the different ripening stages was 0.63, 12.20, 26.76 and 116.66 mg/kg of fresh weight (FW). Vitamin C ranged from 2.79 (breaker Cherry Pera) to 297.62 (red Cherry Pera) mg/kg FW. In green and breaker tomatoes, a positive correlation of hydrophilic antioxidant activity with vitamin C and chlorogenic acid was observed. However, in industrial tomato varieties (red ripe stage) and fresh consumption varieties harvested at pink and red stages, hydrophilic antioxidant activity was correlated with total phenolics and rutin. Tomato varieties for industrial processing did not show significant differences in total phenolic compounds and lycopene content. Lycopene ranged from 83.17 to 97.60 mg/kg FW, while total phenolic compounds varied between 257.91 and 284.13 mg/kg FW. Chlorogenic acid and rutin were the most abundant individual phenolics found in all the samples studied. Moreover, the content of total phenolics was always significantly correlated with the content of rutin. The amounts of all individual phenolics were affected by variety, with the exception of ferulic acid. Generally, these individual phenolics were more abundant in green and intermediate ripening stages, decreasing in full red tomatoes.     

Bioactive Compounds and Antioxidant Activity of Tomato Cultivars

The bioactive compounds of 16 tomato cultivars, grown in the same field for 2 years (2003 and 2004) were investigated. Lycopene (5.7–26.3 mg kg^?1) was the predominant carotenoid, while β-carotene (2.1–11.2 mg kg^?1) and a small amount of lutein (0.02–0.49 mg kg^?1) were found in all tomato cultivars. Kagome 77, the richest source of total carotenoids and L-ascorbic acid, also showed the highest antioxidant activity. β-Carotene and lutein contents of tomatoes differed between 2 years statistically. Antioxidant activities of tomatoes were found between 48 and 118 μmol TEAC 100 g^?1. A significant correlation was only observed between L-ascorbic acid (2.2–13.8 mg 100 g^?1) and antioxidant activity using TEAC assay.     

Comparison of Quality Characteristics of Selected Yellow-and White-fleshed Peach Cultivars

Physical, chemical and sensory characteristics and volatile constituents of five yellow-and six white-fleshed peach cultivars were compared. The soluble solids/titratable acidity ratios were significantly higher and the Minolta “b” values were significantly lower for white-fleshed than for yellow-fleshed cultivars. Shelf life of white-fleshed fruit equalled that of yellow-fleshed fruit. Amounts of five compounds that contribute significantly to typical peach aroma were significantly higher in white-fleshed than in yellow-fleshed peaches. Generally, flesh color showed little influence on hedonic scores, peach impact and sweet/sour balance.     

不同品种山楂活性成分及其抗氧化活性的研究

本文以产自山东地区的山里红和大金星这两个常见山楂品种作为研究对象,山楂冻干制成粉末后测定它们的总酚、总黄酮含量及抗氧化活性(DPPH、ORAC和PSC),并采用HPLC分析抗氧化活性成分的差异。结果显示不同品种山楂中的总酚和总黄酮含量各异,其中山里红果实的总酚(61.91 mg GA equiv./g DW)和总黄酮(55.96 mg catechin equiv./g DW)含量均显著高于大金星。山楂果实提取物均有较好的抗氧化活性,其中山里红品种表现出更好的抗氧化活性,其ORAC及PSC值分别是大金星的1.54和2倍。山楂果实提取液经HPLC法分析,鉴定出7种多酚类化学成分,最主要的酚类化合物为原花青素B2以及表儿茶素,且山里红果实多酚类化合物的含量显著高于大金星。综合比较发现山楂中的活性成分含量及种类各异,且山里红的抗氧化活性较强,是天然抗氧化剂的潜在原料。     

不同品种大豆中的生物活性成分及其抗氧化活性的比较分析

本文以华南地区广泛种植的十种大豆作为研究对象,大豆制粉后测定了其总酚、总黄酮、异黄酮含量及抗氧化活性(DPPH、FRAP、ORAC),并对生物活性成分含量与抗氧化活性之间进行相关性分析。研究结果表明大豆基因型显著影响其生物活性物质含量及抗氧化活性:品种间的总酚含量为3.18~4.47 mg GAE/g,其中品种HC5与HC6具有最高和最低含量;总黄酮含量为0.27~0.39 mg CE/g,其中HC3与HC2具有最高和最低含量;总异黄酮含量为720.24~1285.47μg/g,其中HX3和HC6具有最高和最低含量;对于DPPH和FRAP值,HX1和GXD2分别具有最高和最低值,而品种HX5与HX9的ORAC值分别最高与最低。DPPH、FRAP与TPC、TFC之间存在正相关性,而ORAC与异黄酮含量之间显著负相关。综合比较发现HC5、HX1、HX9等具有较丰富的生物活性物质,而HX1、HX5等的抗氧化活性相对较好,是生产优质大豆食品的原料。     

不同烤烟品种的类胡萝卜素、多酚含量及感官品质的比较

采用反相高效液相色语法对2009年云南种植的5个烤烟品种烟叶的类胡萝卜素和多酚含量进行了测定,并进行了感官评吸.结果表明:①不同品种烤烟的类胡萝卜素和多酚含量存在一定差异,烟叶类胡萝卜素含量以云烟85最高,K326最低,NC297,KRK26和云烟87居中;多酚含量以云烟87最高,NC297次之,KRK26最低.②各烤烟品种不同部位的含量差异表现为:云烟85、云烟87,K326和NC297的中部叶类胡萝卜素含量高于上部叶,KRK26的上部叶高于中部叶;各烤烟品种多酚类含量均为上部叶高于中部叶.③烤烟品种云烟87、云烟85和KRK26的感官质量优于NC297和K326,多酚类物质含量越高对感官质量越不利,类胡萝卜素含量过高或过低对烟叶的感官质量也不利.初步试验结果,类胡萝卜素的适宜含量为115～133μg/g,在此范围内多酚含量越低,烤烟感官品质越好.     

Quality of Minimally Processed Apple Slices from Selected Cultivars

Twelve cultivars were prepared as slices and stored 12 days at 2°C. Changes in respiration and quality factors were compared. Initial respiration rates among cultivars varied from 3.5 mL CO₂/kg/hr in Delicious to 7.6 mL CO₂/kg/hr in Monroe and decreased rapidly during the first 3 days. Idared, McIntosh, Delicious, and Rome showed relatively low respiration throughout storage. Firmness of slices during storage decreased gradually for 7 days and more rapidly thereafter. Empire, Golden Delicious, and Idared apples showed minimum changes in firmness. Change in color of slices was rapid during the first 3 days. Cortland. Emuire. Golden Delicious. New York 674. and Delicious showed least browning. Titratable acidity, pH, soluble solids, and weight changes during storage were small and varied by cultivar. NY674, Cortland, Golden Delicious, Empire, and Delicious showed more desirable attributes for minimal processing.     

基于电子舌与SPME-GC-MS技术的芒果风味物质的比较分析

本研究以金芒、青芒、红玉和贵妃四种芒果为研究对象,应用电子舌技术和顶空固相微萃取-气相色谱-质谱联用技术,比较四个不同品种芒果之间的风味品质差异。电子舌主成分分析(PCA)结果表明:电子舌能很好地区分四种芒果,其中青芒和红玉味觉特征相近,贵妃和金芒味觉特征相近。理化指标显示,水分含量、pH、可溶性固形物等指标与电子舌结果具有高度相关性。采用SPME-GC-MS鉴定四种芒果的挥发性物质,共检测出萜烯类、酯类和醛类等7大类物质,其中烯烃类化合物为芒果的主要挥发性成分,相对含量均达到50%以上。挥发性成分的PCA结果显示能够将四种芒果进行很好的区分,其中青芒和红玉挥发性成分更为接近。得以区分四种芒果的特征挥发性物质有:金芒中(E,Z)-2,6-壬二烯醛、异松油烯、3-己烯-1-醇以及芳樟醇;贵妃中2-蒈烯、(E)-罗勒烯以及4-蒈烯;青芒中a-桉叶烯、己醛以及(E)-3-己烯醛以及红玉中3-蒈烯、柠檬烯。四种芒果的特征挥发性物质的呈香特性与他们整体香气的感官分析结果保持一致。综合理化指标、电子舌、SPME-GC-MS以及香气感官分析结果显示青芒和红玉,金芒和贵妃具有相似的风味特征。     

Optimization of Subcritical Fluid Extraction of Bioactive Compounds Using Hansen Solubility Parameters

ABSTRACT:  Process engineering operations in food and nutraceutical industries pertaining to the design of extraction of value-added products from biomass using pressurized liquids involve a careful selection of the solvent and optimal temperature conditions to achieve maximum yield. Complex molecular structure and limited physical property data in the literature of biological solutes extracted from biomass compounds have necessitated the process modeling of such operations. In this study, we have applied the Hansen 3-dimensional solubility parameter concept to optimize the extraction of molecularly complex solutes using subcritical fluid solvents. Hansen solubility spheres characterized by the relative energy differences (RED) have been used to characterize and quantify the solute–subcritical solvent interactions as a function of temperature. The solvent power of subcritical water and compressed hydroethanolic mixtures above their boiling points has been characterized using the above-mentioned method. The use of group contribution methods in collaboration with computerized algorithms to plot the Hansen spheres provides a quantitative prediction tool for optimizing the design of extraction conditions. The method can be used to estimate conditions for solute–solvent miscibility, an optimum temperature range for conducting extractions under pressurized conditions, and approximate extraction conditions of solutes from natural matrices.     

Effect of Drip Irrigation of Pecan Quality and Relationship of Selected Quality Parameters

The effect of four drip irrigation rates 0, 22.7, 45.4, and 68.1 L/hr/tree (LHT) on several quality parameters of ‘Stuart’ pecans were investigated along with values calculated from inshell weights, volumes, and kernel weights. Irrigation significantly increased kernel yield/tree, nut weight, diameter, kernel specific gravity, fill of nut, oil content, and appearance rating. Values calculated by computer analyses from weights and volumes were useful for evaluating the quality of nuts from the different irrigation treatments. This technique should be useful for researchers engaged in quality evaluations of inshell pecans. Nut size and % fill, and kernel color are the best parameters to estimate quality and value of pecans before actual shelling and processing. Additionally processing costs are partially dependent on nut size (no./kg) and kernel yield.     

食用菌深层发酵物中生物活性物质含量的比较

食用菌深层发酵物中含有很多与免疫相关的生物活性物质。本文以白灵菇、金针菇、茶树菇、平菇、香菇、桑黄、云芝和灰树花八种食用菌为实验材料,利用摇瓶深层发酵技术,对相同发酵条件下,8种食用菌发酵物中的胞外多糖、胞内多糖、黄酮、总酚、VC和可溶性蛋白含量进行了比较。结果表明,灰树花深层发酵物中总多糖产量最高为0.349 g/100 m L,桑黄中的黄酮和可溶性蛋白的产量最高分别为3.92μmol/100 m L和0.58 mg/m L,云芝中的VC产量最高为19.95 g/100 mg,金针菇的总酚产量最高为5.07 mg/100 m L。通过比较,白灵菇的综合指标表现最好,以白灵菇为实验材料进行发酵罐深层发酵,比较摇瓶与发酵罐深层发酵液中各物质的含量变化。结果表明,在发酵罐条件下,白灵菇的胞外多糖和胞内多糖产量明显提高,但黄酮和VC产量增幅不大,说明发酵条件对发酵物中活性物质产量有很大的影响。     

不同渗透方式对芒果脱水效率和品质的影响

为了比较在夏季（30 ℃）和冬季（20 ℃）生产环境下不同渗透方式在芒果脱水效率和品质上的差异,本文以失水率、固增率、水分有效扩散系数、可溶性固形物扩散系数、V_C和总酚保留率以及三态水转化为考察指标,探究固态渗透（SSD）和液态渗透（LOD）对糖渍芒果脱水效率和品质的影响。结果表明,固态渗透的脱水效率以及营养物质保留率高于液态渗透;在糖渍48 h后,在环境温度20 ℃下SSD40（蔗糖:芒果(w/w)=4:10）的失水率和固增率最大为49%和5.11%,SSD20（蔗糖:芒果(w/w)=2:10）的V_C和总酚保留率最高为47.43%和43.66%;在环境温度30 ℃下,SSD40的失水率和固增率最大为57.41%和6.36%,SSD20的V_C、总酚保留率最高为43.79%和42.43%。渗透过程改变了芒果样品中水的结合状态,自由度高的水分向自由度低的方向迁移。本文研究结果将为果干类产品固态渗透预处理技术的应用提供理论参考。     

Effects of Ageing on Selected Cooking Quality Parameters of Rice

Ageing can improve cooking quality of rice by influencing major cooking quality parameters i.e., kernel expansion, water absorption, alkali digestion value, and gelatinization temperature along with changes in internal structure of rice grains. In this research, the effects of natural and artificial ageing on the selected cooking quality parameters of two Malaysian rice cultivars, named Mahsuri and Puteri, were studied. A relation was observed between water absorption and elongation ratio in both varieties under different aging conditions. Alkali digestion value and gelatinization temperature were also influenced by varieties and ageing conditions. This study revealed the potentiality of ageing for the improvement of rice cooking quality.     

荞麦生物活性物质的研究进展

荞麦是一种古老的杂粮作物,在世界一些国家和高寒地区都有种植,在某些地区还是当地的主要粮食作物.由于它的化学和生物学成分独特,目前在食品和医药方面的应用前景十分广阔.本文对其生物活性物质,尤其蛋白酶抑制剂的理化性质及其功能等进行了综述.     

汉麻叶的生物活性成分研究现状

本文对汉麻植株叶子中化学成分的生物活性研究概况进行了综述.汉麻叶中生物活性成分可分为大麻酚类化合物和非大麻酚类化合物,其中很多成分在医药领域具有显著的利用价值,有些已经应用于临床.本文对汉麻叶中不同种类的化合物的提取、分离和分析方法进行了总结,较为全面地论述了国内外有关大麻酚类化合物,特别是△9-THC、CBD、CBN等,以及非大麻酚类化合物,如黄酮、生物碱、多酚类和有机酸等,在抗癌、治疗神经疾病、抗菌、抗紫外、抗氧化等方面的研究进展和应用价值.此外,还对汉麻叶中化学成分在药物和护肤品领域中的应用前景进行了展望.汉麻叶可以作为多种生物活性成分的提取原料,生产具有高附加值的产品,是汉麻综合利用产业链中必不可少的环节.     

5种菠萝果实品质比较与评价

为探究不同品种菠萝果实品质差异,建立菠萝果实的果品优选基础数据库。该研究以金菠萝、台农17号、巴厘、台农11号、台农16号5个品种菠萝为材料,测定其果形指数、果皮和果肉硬度、色度等外观品质及糖度、总糖、可滴定酸、维生素C和总多酚等营养成分含量,对结果进行分析比较,通过“合理-满意度”与多维价值理论结合的方法对菠萝品质进行综合评价。结果表明,5个品种菠萝同一指标之间存在不同程度的差异,在外观品质上,金菠萝的单果质量（1.99±0.27）kg、果形指数（1.67±0.21）、果皮硬度（17.99±5.83）N、侧面果肉硬度（1.68±0.31）N 及侧面果肉 L*值（62.53±4.27）5项指标最高;台农 17号菠萝在侧面果肉 b*值（52.99±4.15）、横切面果肉 L*值（60.83±3.42）和 b*值（40.96±4.74）及中心b*值（50.24±3.06）4项指标最高。在营养成分指标中,金菠萝维生素C含量（31.69±0.43）mg/100 g和总多酚含量（82.53±0.16）mg/L最高;台农17号总黄酮含量（52.42±2.54）mg/L最高;巴厘菠萝糖度（15.17±0.06）%最高;台农 16 号果肉 pH 值（3.91±0.10）、总糖含量（114.46±7.37）g/kg、可滴定酸含量（8.53±1.48）%最高。“合理-满意度”综合评价结果表明,金菠萝、台农17号两个品种菠萝品质相对较好。     

切分方式对鲜切哈密瓜品质和活性成分含量的影响

本实验将哈密瓜切分成梯形、方块和片状,置于10 ℃贮藏72 h,研究不同切分方式对鲜切哈密瓜贮藏期间品质及总酚和γ-氨基丁酸（γ-aminobutyric acid,GABA）含量的影响。结果表明：鲜切处理促进了哈密瓜L值、a值、b值、硬度、可溶性固形物质量分数和抗坏血酸含量的下降及菌落总数和透明率的上升,且损伤程度越大,其变化幅度越大。同时,鲜切处理可显著诱导苯丙氨酸解氨酶（L-phenylalanine ammonialyase,PAL）及谷氨酸脱羧酶（glutamate decarboxylase,GAD）活力、总酚及GABA含量和1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力的上升（P＜0.05）,以切分损伤强度最大的切片处理组PAL、GAD活力及DPPH自由基清除能力最高,酚类物质和GABA积累最多。综上,切分处理虽可加速鲜切哈密瓜品质的下降,但同时可促进酚类和GABA等生物活性成分的积累,提高其抗氧化活性。     

Effects of Hypobaric Treatments on the Quality,Bioactive Compounds,and Antioxidant Activity of Tomato

Hypobaric treatment is becoming a potential technology to protect fruits from postharvest decay. The objective of this study was to investigate the effects of hypobaric treatments on storage quality, bioactive compounds, and antioxidant activity of tomato fruit. In this study, green tomatoes (cv. “Fen guan”) were treated with hypobaric pressures (0.04 and 0.07 MPa) at ambient temperature (20 ℃) for 28 d. The results showed that under hypobaric storage, the respiration rates significantly declined and the respiratory peaks postponed 12 and 8 d by 0.04 and 0.07 MPa treatments, respectively, compared to control. Total soluble solid, titratable acidity, ascorbic acid, and lycopene were retained by hypobaric treatment. Moreover, ascorbic acid contents treated with 0.04 and 0.07 MPa were, respectively, 37% and 26% higher than control at day 24 and the contents of total polyphenols were, respectively, 1.28 and 1.11 times higher than control. Production and accumulation of toxic substances were significantly restrained. The ethanol content decreased, respectively, by 53% and 84% than control. At later storage period, the superoxide dismutase activity in treated fruits was about 0.58 U/(g·FW·min), whereas only 0.29 U/(g·FW·min) in control. Hypobaric treatment not only maintained a high activity of superoxide dismutase and peroxidase (POD), but also improved antioxidant capacity. All the results indicated that hypobaric treatment was a potential helpful method to protect the quality and nutrition of tomato and prolong ripening of tomato. Furthermore, the effect of 0.04 MPa hypobaric treatment was found better than 0.07 MPa.