不同包装方式对南疆薄皮鲜食核桃营养品质的影响研究

为探明新疆两种鲜食薄皮核桃贮藏过程中营养成分的变化及最佳包装贮藏方式,以南疆主栽品种温185和新2鲜食核桃仁为试材,以普通塑料袋散装为对照,分别采用充N2、铝箔和真空3种包装方式,在常温20~25℃下贮藏80 d,研究不同品种核桃仁贮藏过程中营养品质的变化,以及各品质指标之间与品种、包装处理、贮藏时间之间的关系。结果表明,包装处理组能有效抑制鲜食核桃仁粗脂肪、粗蛋白、水分、总糖和总酸含量的变化,其中铝箔包装能有效保持鲜食核桃仁的水分含量,维持粗脂肪和粗蛋白含量的稳定,减缓总糖含量的下降和总酸含量的上升,贮藏效果较好。不同核桃品种间的各营养品质指标差异显著,相关性分析结果表明:水分含量与除总糖外的其他营养指标呈极显著负相关;最终确定薄皮核桃仁最佳贮藏包装方式为铝箔包装。     

包装方式对红枣品质的影响

不同包装方式下常温贮藏效果研究表明,经真空包装的红枣水分含量、色差、褐变度、总糖含量、感官品质都较好地保持了包装前的特性,在真空包装中加入吸潮剂效果不明显;采用保鲜袋包装对红枣水分含量、色差、褐变度、总糖含量、感官品质的变化起到了一定抑制作用,但是这种作用持续时间较短,贮藏后期的红枣营养成分和感官品质均下降、货架期缩短。结果显示,真空包装是红枣常温贮藏较为合适的包装方式,适用于在红枣干燥后贮藏。     

苦荞酒酿蛋羹贮藏期间品质的变化

为了苦荞酒酿蛋羹产品的产业化,利用菌落总数、大肠杆菌、理化指标及感官评价研究了不同包装和贮藏温度下全蛋和蛋粉苦荞酒酿蛋羹品质的变化。结果表明,当贮藏温度为4±2℃时,2种包装的贮藏时间平均都在13 d以内,真空包装比盒装包装贮藏时间略长;蛋粉包装的糖度值高于全蛋产品包装,全蛋包装的pH值和持水力高于蛋粉包装的产品;2种包装的感官评价在9 d以内评分较高。苦荞酒酿蛋羹贮藏最佳条件为真空包装,温度4±2℃,保质期最长为12 d,但最佳食用时间为9 d以内。     

贮藏温度对甜高粱秸秆糖分含量的影响

研究冷冻（-18℃）、冷藏（5℃）、室温（20℃）等3种不同贮藏温度下甜高粱秸秆的糖分和水分含量的变化规律,讨论贮藏温度对甜高粱秸秆贮藏效果的影响。结果表明：冷冻贮藏水分变化相对平稳,室温下秸秆水分剧烈降低;3种不同温度下秸秆总糖含量之间的差异达极显著水平,冷冻贮藏下各时期总糖含量的变化差异不显著,冷藏和室温下总糖含量的变化差异极显著;冷冻条件对贮藏前期茎秆还原糖含量的影响不显著,秸秆还原糖含量的变化曲线平稳;蔗糖含量在整个贮藏期内总的变化均呈降低的趋势,低温处理的茎秆蔗糖含量降低趋势较慢,蔗糖含量明显高于同期的室温贮藏秸秆的蔗糖含量。糖含量随着处理时间的延长,变化不显著者可认为贮藏效果较好,变化显著者可认为糖代谢活动活跃而影响糖含量的变化,所以3种方法中冷冻贮藏方法较为合适。甜高粱茎秆在生产加工过程中如果条件允许以冷冻的方式进行贮藏。     

不同贮藏方式对鲜食核桃品质的影响

为研究不同贮藏方式对鲜食核桃在贮藏过程中品质的影响,以“清香”核桃鲜果为试材,分别采用青果贮藏（(0±1) ℃、相对湿度70%～80%）、去青皮的湿果贮藏（(-7±1) ℃、相对湿度70%～80%）及湿果真空贮藏（(-7±1) ℃、相对湿度70%～80%）3种方式贮藏,每15 d对其品质指标进行观察测定。结果表明：随着贮藏时间的延长,所有贮藏方式处理的鲜食核桃的感官品质和营养成分均呈一定的下降趋势。其中,青果贮藏能较好地保持核仁的含水量,维持粗脂肪、蛋白质及可溶性糖含量的稳定性,贮藏后种皮色泽较好,核仁容易剥皮、风味较好,但果壳容易产生霉变;湿果贮藏和湿果真空贮藏可以减轻鲜核桃的霉变,延长了鲜核桃贮藏期,但随着贮藏时间的延长,湿果贮藏核仁水分散失较快,粗脂肪、蛋白质及可溶性糖含量变化较大,使得种皮色泽降低,核仁剥皮困难、风味下降。     

贮藏温度对鲜切山药品质的影响

为了明确鲜切山药段在不同贮藏温度下的品质变化规律,为生产中鲜切山药适宜销售期提供指导,以去皮山药段为对象,研究了4种贮藏温度（0、5、10、15 ℃）下鲜切山药硬度、褐变指数、菌落总数、总酚含量、PPO活性及感官品质的变化情况。结果表明：贮藏期间,0 ℃贮藏的样品硬度最高;贮藏2 d后,0 ℃和5 ℃贮藏样品的褐变指数显著低于其他贮藏组;0 ℃和5 ℃贮藏样品的总酚含量、PPO活性先升高后下降,贮藏12 d时总酚含量分别为初值的1.72倍和1.14倍,PPO活性与10 ℃贮藏相比,分别下降了40.86%、48.53%;0、5、10、15 ℃贮藏样品分别在10、8、4、2 d内感官品质不低于商业标准。总之,0 ℃和5 ℃低温贮藏可以有效保持去皮山药段的硬度,抑制PPO活性,减轻样品褐变,保持较高的感官品质。     

油炸食品在贮藏过程中水分和脆性变化研究

为了探究油炸食品在贮藏过程中水分含量和脆性变化及其对油炸食品感官品质的影响,以方便面、锅巴、麻花和薯片等油炸食品为试验材料,通过Schall法(60℃),每隔3 d测定1次水分含量和硬度,并观察油炸食品感官品质的变化。结果表明,油炸食品水分含量随贮藏时间的延长逐渐减少,变化范围为4.78%~1.28%;脆性随贮藏时间的延长逐渐增大,不同食品差异较大,变化范围为92.79~15 373.42 g。同时,油炸食品贮藏过程中水分含量减小、硬度增大,食品变脆。     

不同包装方式对蓝莓月饼储藏品质的影响

采用加速破坏性实验模型,分别对经过脱氧包装、真空包装、普通包装的蓝莓月饼和未添加防腐剂的对照组蓝莓月饼进行保质期预测研究,并对储藏期间的基础营养指标进行探究,确定对蓝莓月饼品质保持效果较好的包装方式.结果 表明:在常温25℃、相对湿度60％条件下,脱氧包装组保质期最长,为63.00 d;空白对照组保质期最短,为31.50 d;真空包装组和普通包装组保质期分别为50.40 d和43.75 d;并且,真空包装和脱氧包装也能更好地防止蓝莓月饼水分含量增加,减少脂肪、总糖和蛋白质被消耗.结合感官评分结果,脱氧包装是保持蓝莓月饼储藏品质最好的一种包装方式.     

贮藏温度对酸羊奶品质的影响

研究了不同贮藏温度对酸羊奶贮藏期间理化特性、乳酸菌活菌数和感官品质的影响。结果表明,在4℃和8℃下,可延缓酸羊奶贮藏期间酸度的上升和黏度的下降,而12℃贮藏酸羊奶的酸度增长较快,黏度下降明显;在4℃和8℃下,酸羊奶贮藏4d,酸奶中的保加利亚乳杆菌和嗜热链球菌活菌数基本保持稳定,随着贮藏时间的延长呈显著下降趋势(p<0.05);贮藏温度为4℃,在14d的贮藏期内酸羊奶感官品质保持良好,而12℃贮藏条件加速了酸奶品质劣化,保质期只有4d。分析认为,贮藏温度为4℃时,更有利于酸羊奶良好品质的保持。     

鲜食糯玉米采后糖代谢变化

【研究目的】了解鲜食糯玉米采后的糖代谢变化以及温度变化对糖代谢的影响。【方法】测定鲜食糯玉米采后的蔗糖、还原糖、直链淀粉、支链淀粉的含量变化。【结果】鲜食糯玉米采后的蔗糖、还原糖含量都有较大下降;采后第1d直链淀粉、支链淀粉和总淀粉的含量都达到峰值,之后直链淀粉变化不大,支链淀粉的含量略有下降,总淀粉含量呈增加趋势;与20℃贮藏温度对比,贮藏温度为0℃时蔗糖、还原糖含量、直链淀粉含量高,支链淀粉、总淀粉含量低。【结论】鲜食糯玉米采后可溶性糖向淀粉转化的合成代谢仍然占据主导地位,贮藏温度为0℃时能够延缓可溶性糖向淀粉,以及直链淀粉向支链淀粉的转化。     

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.     

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.     

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.     

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.     

Present status and future strategy in breeding faba beans (Vicia Faba L.) for resistance to biotic and abiotic stresses

Progress is being made, mainly by ICARDA but also elsewhere, in breeding for resistance to Botrytis, AScochyta, Uromyces, and Orobanche; and some lines have resistance to more than one pathogen. The strategy is to extend multiple resistance but also to seek new and durable forms of resistance. Internationally coordinated programs are needed to maintain the momentum of this work.Tolerance of abiotic stresses leads to types suited to dry or cold environments rather than broad adaptability, but in this cross-pollinated species, the more hybrid vigor expressed by a cultivar, the more it is likely to tolerate various stresses.     

Water Extraction Process of Chinese Herbal Compound Man Gan Ning

[Objectives]To optimize the water extraction process of Chinese Herbal Compound Man Gan Ning and establish a method for its extraction and content determination...