甲基红-溴百里酚蓝新鲜度指示标签在果蔬保鲜上的应用

随着生鲜电子商务新业态的发展以及市场对保鲜包装功能要求的提高,制备能够直观表达果蔬新鲜度的指示标签具有重大意义。将甲基红与溴百里酚蓝以体积比3∶2混合作指示剂,以增塑剂聚乙二醇-6000、粘合剂甲基纤维素作成膜基质,制备基于pH值变化的果蔬新鲜度指示标签,并研究其在草莓、生菜包装上的新鲜度指示效果。结果表明：随着贮藏时间的延长,果蔬包装内CO2体积分数不断上升,pH值不断下降;所制备的4种指示标签的颜色均发生变化,其中标签3（50 mL/L甲基红-溴百里酚蓝混合指示剂）和标签4（70 mL/L甲基红-溴百里酚蓝混合指示剂）的颜色变化范围最广,涵盖绿色、黄绿色、橙色和红色4个色系,且标签3的色差值?驻E与果蔬的新鲜度感官评分的拟合度最高（R2=0.834 6）。因此,50 mL/L的甲基红-溴百里酚蓝新鲜度指示标签的指示效果最好。     

水溶性可食酸碱指示膜的初步研究

以可食性食品原料作为载体,通过对比不同添加量普鲁兰多糖对可食膜柔韧性、脆性、黏性等质构指标和溶解时间等指标,确定了水溶性可食膜的配方为明胶添加量5%,甘油添加量0.5%,海藻糖添加量0.5%,普鲁兰多糖添加量2.5%;继而对比分析了紫桑葚粉在不同pH值下色差及颜色变化,确定采用0.02%的桑葚粉加入普鲁兰多糖-海藻糖-甘油-明胶可食膜中,其溶于水后可通过颜色的变化实现对食品酸碱程度的表征。     

红枣灵芝多糖复合饮料的研制

研究一款以红枣和灵芝多糖为主要原料的新型饮料。以超临界CO2萃取灵芝孢子油后所剩的灵芝孢子粉为原料,经水提醇沉技术获得灵芝多糖;通过单因素试验和正交试验等方法对红枣灵芝多糖复合饮料的制备及稳定性进行研究。结果表明,红枣汁最佳制备工艺为：红枣清洗去核,以液料比30∶1（mL/mg）的比例加入水,煮沸30 min后,用超声水提处理2次,超声提取70 min,温度70 ℃;灵芝多糖最佳提取条件为：液料比35∶1（mL/mg）,提取温度40 ℃,超声波功率600 W下提取90 min;红枣灵芝多糖复合饮料最佳配方为：红枣汁添加量250 g/L,灵芝多糖添加量50 g/L,柠檬酸添加量15 g/L,木糖醇添加量40 g/L,壳聚糖添加量0.2 g/L。所得产品口感饱满、风味鲜美且稳定性好,是一种新型的集营养与保健于一体的多功能复合饮品。红枣灵芝多糖复合饮料的开发满足了目前功能性产品开发趋势的需求,同时,也可为优质功能性红枣产品、灵芝多糖产品的开发提供借鉴。     

豆渣水溶性膳食纤维的复合酶法提取及其应用于可食性膜研究

以豆渣为原料,通过膨化辅助复合酶解法提取豆渣可溶性膳食纤维（SDF）,然后将其制成可食性膜,并利用正交试验对豆渣SDF的提取条件和成膜条件进行优化。结果表明,豆渣SDF最佳提取条件为：豆渣与蒸馏水之比1∶30（g∶mL）,纤维素酶添加量30 g/L（以蒸馏水添加量计）,酶解时间2 h,蛋白酶酶解体系pH值为9.0;最佳成膜条件为：豆渣SDF 1.0 g,CMC-Na添加量1.0 g,海藻酸钠添加量1.5 g,甘油添加量4.5 mL。该条件下制得的豆渣可食性膜不但光滑,而且性质稳定,水溶解速度为0.098 mg/s,水滴漏时间为12 060 s。     

主成分分析法结合响应面优化亚麻籽胶与壳聚糖复合膜成膜工艺

为优化亚麻籽胶与壳聚糖复合膜的成膜工艺，以亚麻籽胶和壳聚糖为主要材料制备复合膜，研究亚麻籽胶膜液∶壳聚糖膜液(V/V)、壳聚糖质量浓度和甘油添加量对复合膜性能的影响，并以复合膜性能综合评分为考察指标，结合主成分分析法和响应面试验法，优化复合膜制备工艺参数。结果表明，复合膜最优制备工艺为：亚麻籽胶膜液∶壳聚糖膜液(V/V)为20∶10，壳聚糖质量浓度1.0 g/100 mL，甘油质量分数21%；在此条件下制备的复合膜性能综合评分为0.724，膜的各项指标分别为：拉伸强度(18.16±0.17)MPa，断裂伸长率57.15%±0.14%，水蒸气透过率(1.30±0.02)(g·mm)/(h·m²·kPa)，氧气透过率(7.30±0.08)cm³/(m²·d·Pa)，透光率95.55%±0.09%。该研究结果可为复合膜在食品保鲜中的应用提供理论基础。     

增塑剂甘油对陈米粉可食性包装薄膜性能的研究

以陈米粉为基质开发一种新型的廉价且性能优良的可食性薄膜。将陈米研磨成粉作为成膜基材,增塑剂为甘油,添加0.25 mol/L的Na OH调节溶液p H值,于80℃中水浴加热30 min,浇膜于22 cm×23 cm透明塑料薄板上,并放入干燥箱干燥3.5 h后即可得膜。通过改变增塑剂甘油的配比,并对膜的主要性能指标进行测试。陈米粉添加量为7 g,甘油添加量为3.5 m L,Na OH的体积为7 m L时,膜综合性能良好。该膜具有良好的机械性能,是一种具有广阔发展前景的环保食品包装材料。     

超临界流体萃取芦荟多糖的研究

通过超临界CO2流体萃取处理芦荟多糖,多糖得率为85.1%,是传统方法的1.5倍。超临界萃取的最佳工艺条件是乙醇用量为250mL/100g芦荟、萃取压力为25MPa、萃取温度为35℃。     

A precise finite element modeling approach for analyzing linear rolling guideway dynamics

以燕麦加工产品的剩余滤渣为原料,研究酶-碱结合法制备燕麦麸膳食纤维的提取工艺。在单因素试验的基础上,通过正交试验,确定提取燕麦麸膳食纤维的最佳工艺条件为:料水比1∶10,α-淀粉酶添加量1.5%,溶液pH 6.5,65℃条件下酶解30 min,酶解液加3%浓度为1 mol/L的NaOH溶液,60℃条件下碱解40 min。制得的燕麦麸膳食纤维的提取率可达56.43%,持水力为3.414 9 g/g,溶胀性为3.13 mL/g。     

海带多糖酶解辅助提取工艺的响应面优化及其稳定性研究

对海带加工下脚料中多糖的酶解提取工艺和化学稳定性进行研究。在单因素试验基础上，采用响应面法对酶解辅助提取的工艺参数进行优化，得出4种酶解因素对海带加工下脚料中多糖提取量影响顺序依次为：复合酶添加量＞pH ＞酶解时间＞温度。最优工艺条件为：液料比40∶1（mL/g），酶解时间135 min，酶解温度55 ℃，酶解液pH 6.0，复合酶添加量2.0%。在该条件下，制得的海带多糖提取量为149.662 g/kg。化学稳定性试验表明，海带多糖提取物在高温和酸性环境下，具有良好的化学稳定性，对碱性环境稳定性较差，是一种化学稳定性较好的天然活性多糖。     

蒲公英根多糖提取及蒲公英多糖饮料的研制

以蒲公英根为原料,采用热水浸提法提取蒲公英根多糖,通过单因素试验及正交试验确定了蒲公英根多糖提取的最优工艺参数为料液比1∶40(g∶mL),提取温度80℃,提取时间3 h,提取次数2次,在此提取条件下,其多糖得率为8.945%。另制备多糖提取液作为蒲公英根多糖饮料的原液,强化添加蒲公英多糖,再辅以柠檬酸、甜菊糖等,复配研制蒲公英多糖饮料,通过感官评价得出饮料的最佳配方为蒲公英原液64%,蒲公英多糖添加量3.04%,柠檬酸添加量0.08%,甜菊糖添加量2.5%,以此配方研制的蒲公英饮料口味独特、澄清透明、营养丰富,蒲公英多糖含量为5.18%,为蒲公英的深加工及综合利用提供了有益的参考。     

Biological Activity and Quantification of Suspected Allelochemicals from Alfalfa Plant Parts

Autotoxicity restricts reseeding of alfalfa (Medicago sativa L.) after alfalfa until autotoxic chemical(s) breaks down or is dispersed into external environments. A series of aqueous extracts from leaves, stems, roots and seeds of alfalfa ‘Vernal’ were bioassayed against alfalfa seedlings of the same cultivar to determine their autotoxicity. The highest inhibition was found in the extracts from the leaves. Extracts at 40 g dry tissue l^?1 from alfalfa leaves were 15.4, 17.5 and 28.7 times more toxic to alfalfa root growth than were those from roots, stems and seeds, respectively. A high‐performance liquid chromatography (HPLC) analysis with nine standard compounds showed that the concentrations and compositions of allelopathic compounds depended on the plant parts. In leaf extracts that showed the most inhibitory effect on root growth, the highest amounts of allelochemicals were detected. Among nine phenolic compounds assayed for their phytotoxicity on root growth of alfalfa, coumarin, trans‐cinnamic acid and o‐coumaric acid at 10^?3 m were most inhibitory. The type and amount of causative allelochemicals found in alfalfa plant parts were highly correlated with the results of the bioassay, indicating that the autotoxic effects of alfalfa plant parts significantly differed.     

Changes in Seed Yield and Quality with Maturity in Onion (Allium cepa L., cv. 'Early Cream Gold')

Development of onion (Allium cepa L., cv. ‘Early Cream Gold’) seed under cool climate conditions in Tasmania, Australia occurred over a longer duration than previously reported, but similar patterns of change in yield components were recorded. In contrast to previous studies, umbel moisture content declined from 85 to 67 % over 57 days while seed moisture content decreased from 85 to 31 %. Seed yield continued to increase over the duration of crop development, with increasing seed weight compensating for seed loss resulting from capsule dehiscence in the later stages of maturation. Germination percentage was high and did not vary significantly from 53 to 77 days after full bloom (DAF), but mean germination time declined and uniformity of germination increased significantly over the same time period. The percentage abnormal seedlings declined with later harvest date, resulting in highest seed quality at 77 DAF. The results of this study suggest that the decision to harvest cool climate onion seed crops before capsule dehiscence will result in a loss of potential seed yield and quality.     

Location of a high-lysine gene and the DDT-resistance gene on barley chromosome 7

Summary The high-lysine gene in Risø mutant 1508 conditions an increased lysine content in the endosperm via a changed protein composition, a decreased seed size, and several other characters of the seed. The designation lys3a, lys3b, and lys3c, is proposed for the allelic high-lysine genes in three Risø mutants, nos 1508, 18, and 19. Linkage studies with translocations locate the lys3 locus in the centromere region of chromosome 7. A linkage study involving the loci lys3 and ddt (resistance to DDT) together with the marker loci fs (fragile stem), s (short rachilla hairs), and r (smooth awn) show that the order of the five loci on chromosome 7 from the long to the short chromosome arm is r, s, fs, lys3, ddt. The distance from locus r to locus ddt is about 100 centimorgans.     

A note on the origin of Kalanchoë x vadensis Boom & Zeilinga (Crassulaceae)

Summary K x vadensis is a hybrid of K. blossfeldiana and K. marmorata obtained after doubling the number of chromosomes.     

Simultaneous Determination of Four Phenolic Acids in Radix Salviae Miltiorrhizae Formula Granules by QAMS

[Objectives]This study aimed to establish a QAMS(quantitative analysis of multi-components by single-marker)method for simultaneous determination of four phenol...     

Avoidance of leaf rust fungi in wild relatives of cultivated cereals

Summary Avoidance of rust fungi that was based on poor appressorium induction was previously found in Hordeum chilense. In the present study 95 accessions of Triticeae were screened for avoidance of Puccinia hordei. The percentage of appressorium formation per germinated spore ranged from 6 to 90%. On none of the 41 accessions of Aegilops, Agropyron, Elymus, Secale, Thinopyrum or Triticum studied was the rate of appressorium formation lower than 25%. Lower rates of appressorium formation were, however, found on accessions of wild barley species Hordeum brachyantherum, H. marinum, H. parodii and H. secalinum. Its implications in cereal breeding are discussed.     

Variation in forage grasses as hosts of the root-knot nematode Meloidogyne naasi (Franklin) and selection for resistance in ryegrass

Summary Reactions of 13 grasses to Meloidogyne naasi varied with species; ryegrasses, fescues and their hybrids were generally susceptible and cocksfoot and timothy resistant. Marked variation in host resistance levels occurred between genotypes within cultivars.Selection of single plants, followed by tests on replicate tillers, identified resistant and susceptible genotypes in both Italian and perennial ryegrass cultivars. Resistant plants had few nematode-induced galls and fewer females and eggs than susceptibles. There was more or less continuous variation, with many genotypes intermediate between extremes of resistance and susceptibility. Selected resistant and susceptible genotypes are of use in assessing variation in nematode populations and as controls for breeding and selection programmes.     

Current and future strategies in breeding lentil for resistance to biotic and abiotic stresses

Lentil production is limited by lack of moisture and unfavorable temperatures throughout its distribution. Waterlogging and salinity are only locally important. Progress has been made in breeding for tolerance to drought through selection for an appropriate phenology and increased water use efficiency and in breeding for winter hardiness through selection for cold tolerance.The diseases rust, vascular wilt, and Ascochyta blight, caused by Uromyces viciae-fabae, Fusarium oxysporum f. sp. lentis, and Ascochyta fabae f. sp. lentis, respectively, are the key fungal pathogens of lentil. Cultivars with resistance to rust and Ascochyta blight have been released in several countries and resistant sources to vascular wilt are being exploited. Sources of resistance to several other fungal and viral diseases of regional importance are known. In contrast, although the pea leaf weevil (Sitona spp.) and the parasitic weed broomrape (Orobanche spp.), and to a lesser extent the cyst nematode (Heterodera ciceri), are significant yield reducers of lentil, no sources of resistance to these biotic stresses have been found. Directions for future research in lentil on both biotic and abiotic stresses are discussed.     

Breeding forage grasses for organic conditions

Herbage yield trials are necessary to test if candidate varieties are well suited for organic conditions. In order to elucidate a particular suitability for organic conditions, we run such trials in parallel under both organic and conventional conditions. Here, we report on second and third year results of the sowings 2004 and 2005. These trials are part of a targeted breeding programme for organic conditions. Irregular colonisation of pure grass plots with adventitious plants, in particular white clover, was recognized as a major constraint to the quality of the results obtained under organic conditions. The coefficients of variance in dry matter yield almost doubled when compared to conventional trials, and significant differences in annual yield among varieties were rare. However, when herbage yield was corrected for the estimated fraction of adventitious plant colonization at each cut, the number of instances with statistically significant differences for annual yield among varieties increased more than fourfold. Dry matter yields under organic and conventional conditions were significantly and positively correlated. However, analysis of variance showed a significant culture type by variety interaction for annual dry matter yield in 12 out of 24 trials. When diploid and tetraploid varieties of the same Lolium species were tested in one common trial, only tetraploid varieties were identified as being particularly well suited for organic conditions, while in these trials, the great majority of apparently poorly suited varieties were diploid. This suggests that breeding tetraploid Lolium varieties is promising when aiming at a favourable response to organic agriculture.     

The performance of double or mixed pollinations with compatible and self-incompatible or incongruous pollen of pear and apple

Summary Six pear and five apple trials were carried out to ascertain the outcome of combinations of compatible pollen (C) with self (S) or incongruous pollen (I) as to the pollination index (PI=seeds/pollinated flower). The PI of the mixture C+I (1:5) was consistently depressed as compared to that of the control C. The results of the double pollinations S/C and I/C were affected by the temperature at pollination; their PI's at <15°C were twice as high as those at >15°C, being well above and below the PI of C in the former and latter case respectively. The opposite was true for the C/S combination, the PI of which increased with the pollination temperature; the PI of C/I did not differ much from the PI of C, irrespective of temperature. The conclusion was reached that the interaction previously and presently found between compatible and self-incompatible pollen also exists to a fair extent between compatible and incongruous pollen. However, in pear neither the mentor nor the pioneer pollen technique proved to aid its hybridization with apple, the formation of self seed was not observed either. In apple the production of apple × pear hybrids was likewise doubtful, but the double pollinations S/C and C/S formed 4–10% self seed.