鲜食糯玉米连玉糯1号栽培及速冻加工与保鲜技术

从鲜食糯玉米速冻工艺流程、检验指标、贮藏及运输条件等方面进行了概述,系统地阐述了鲜食糯玉米连玉糯1号从原料到加工,再到运输销售等各个环节的操作技术标准,旨在为鲜食糯玉米速冻加工与保鲜提供技术指导.     

影响糯玉米鲜食品质因素的研究

根据国内外目前有关鲜食糯玉米研究的现状,就与糯玉米鲜食品质密切相关的适宜采收期、速冻保鲜技术、栽培技术措施等因素,以及造成口感差异因子的研究作一简要总结,并就目前研究中存在的问题,提出了一些建议和看法。     

晋单(糯)41玉米及其产业化开发

叙述了晋单(糯)41玉米新品种的特征特性、优质高效栽培技术、速冻保鲜和真空保鲜加工技术;在糯玉米产业化中品种、技术、产品之间的紧密关系:品种决定产品档次和种植加工效益,品种又必需有配套的栽培、保鲜加工技术作依托,才能充分发挥自身特性,保证加工产品的产量和质量;晋单(糯)41的育成和产业化开发形成了山西省地方性龙头产业,并对我国糯玉米的科研育种、生产开发、加工增值起到了积极的推动作用。     

速冻保鲜甜玉米的营养品质分析

本文采用对比分析法实测普通玉米、甜玉米完熟果穗、鲜穗和速冻保鲜果穗的主要感官营养品质成分,以探讨速冻保鲜处理对甜玉米品质的影响.结果表明,速冻保鲜处理后甜玉米的Vc含量、含糖量,以及赖氨酸、色氨酸等主要氨基酸含量稍有降低,基本上与鲜果穗相近.感官品质也符合要求.     

第三届全国鲜食玉米暨速冻食品产业大会

时间地点:9月23日报到,24～25日开会,吉林省宾馆(长春市)大会内容:●鲜食玉米暨速冻食品产业论坛-由国内知名专家做"甜、糯玉米加工新技术","甜、糯玉米市场前     

晋单(糯)41玉米新品种的选育与推广

晋单(糯)41玉米是山西省农业科学院玉米研究所1996年以自选系N9603作母本,自选系N9605作父本杂交育成的早熟黄糯玉米杂交种,经1997～2000年的品比、生产试验、专家田间鉴定、抗病鉴定、品质分析,该品种生育期较短、抗逆性好、品质优良、高产稳产,适宜在我国玉米种植区种植,且可以单种,复(套)种,春、夏、冬播种,该品种是目前鲜食玉米青穗直接出售或速冻、真空包装保鲜加工以及糯玉米糁、糯玉米面、糯淀粉等深加工的理想品种,种植密度为每公顷45 000～52 500株^[1]。     

速冻鲜食玉米穗加工技术

本文通过对青嫩玉米穗市场的浅析,提出特种玉米开发的原则是:采用农户—公司—集团的经济模式,适度、规模,按品种区域发展,产后加工创名牌,出口创汇增效益。指出了适合速冻青嫩玉米穗加工的系列专用品种(甜玉米类、糯玉米类、高营养玉米类、特色香型玉米等),详述了系列青鲜玉米速冻加工的工艺流程及应注意的问题。     

优质白糯玉米新品种晋鲜糯6号的选育与应用

晋鲜糯6号玉米是山西省农科院玉米研究所于2001年以自选系N16为母本,自选系N18为父本杂交组配而成的中熟白糯玉米杂交种。经2002～2005年的品比试验、生产试验、田间鉴定、抗病鉴定和品质分析表明,该品种生育期短,抗逆性好,品质优良,稳产高产,可以单种,复(套)种,春、夏、冬播种。也是目前鲜食玉米青穗直接出售或速冻、真空包装保鲜加工的理想品种。种植密度52 500～60 000株/hm2。     

优质白糯玉米新品种鲜糯2号选育报告

鲜糯2号玉米是山西省农科院玉米研究所1999年以自选系N9908作母本,自选系N9904作父本杂交育成的中早熟白糯玉米杂交种。经2000～2004年的品比、生产试验、专家田间鉴定、抗病鉴定和品质分析,该品种生育期较短、抗逆性好、品质优良、稳产高效,适宜在很多玉米种植区种植,且可以清种,复(套)种,春、夏、冬播种,该品种是目前鲜食玉米青穗直接出售或速冻、真空包装保鲜加工的理想品种,种植密度为52500～60000株/hm2。     

糯玉米银糯一号特征特性与配套优质栽培技术

本文提出优良的糯玉米新品种和配套的栽培技术是促进糯玉米生产健康发展的重要保证.以北京市审定的糯玉米新品种“银糯1号“的为例,论述其选育的基本过程和主要特征特性,为达到生产优质、丰产、绿色的“银糯1号“糯玉米,而提出一系列的配套栽培技术,包括择地、种植、管理、施肥、病虫害防治、收获和保鲜等.鲜食采收期确定为授粉后第22～28d是各种营养物质积累最佳和风味品质最佳时期.     

不同品种芒果块液氮速冻-解冻后质构特性比较研究

为评价不同品种芒果块液氮速冻后的品质特性,以桂热、金煌、凯特、紫花、红象牙等10个广西芒果品种为对象,对其速冻-解冻前后样品的开裂率、感观品质、色度以及硬度、凝聚性、弹性、咀嚼性等质构特性进行测试。结果表明,经液氮速冻后,10个品种芒果块的感官品质均有所下降,90%芒果品种出现开裂现象,硬度、咀嚼性下降幅度较大,色度、凝聚性、弹性下降幅度相对较小;其中桂热10号、金煌芒、紫花芒3个品种在液氮速冻-解冻后保持相对较高的品质。说明液氮速冻对不同品种芒果块品质的影响不同,本研究为液氮速冻应用于速冻芒果的加工提供理论依据和技术支持。     

Effect of quick-freezing temperature on starch retrogradation and ice crystals properties of steamed oat roll

Oat roll is one of the traditional oat wholemeal foods. The purpose of this work was to investigate the effects of quick freezing at −20 °C, −40 °C and −80 °C for 90 min before frozen storage on the quality of frozen steamed oat roll. Quick freezing at −40 °C and −80 °C inhibited the increase of peak gelatinization temperature, enthalpy and the ordered degree of oat roll starch, therefore postponing starch retrogradation. The cross-section microstructure confirmed that reducing the quick-freezing temperature could prevent the increase of ice crystals size, ruptured structures and maintain the integrity of internal structure. As the storage time extend, the ice recrystallization led to an increase in size of ice crystals, while a decrease in their number. Frozen steamed oat roll starch had the highest swelling power at the quick-freezing temperature of −80 °C, that indicated strongest water absorption and binding ability when gelatinized again. Texture analysis demonstrated that hardness increased during frozen storage, quick freezing at −80 °C had the best texture properties. Therefore, declining the quick-freezing temperature could obtain a higher quality of frozen steamed oat roll, by means of delaying the starch retrogradation and minimising the size of ice crystals.     

不同小麦品种春化反应与抗寒性关系初探

选择北移号、8066、苏引10号、鲁麦22号、晋春9号等五个不同类型小麦品种，通过低温春化处理，观察不同品种的春化反应和抗寒性表现，以研究其春化反应与抗寒性的关系。结果表明，不同类型品种抗寒性差异较大，同一品种经不同低温春化时间处理后幼苗的抗寒性不同，且随着春化时间的延长，抗寒性增强，适宜春化时间处理幼苗的抗寒性最强；在小麦生长发育过程中，要求较长低温春化时间的品种，抗寒性不一定强，但抗寒性强的品种，要求的春化时间一般较长；低温春化特性与抗寒性是品种的两种性质，低温春化有利于小麦抗寒性的形成。     

Freezing tolerance of winter wheat plants frozen in saturated soil

Winter wheat is sown in the autumn and harvested the following summer, necessitating the ability to survive subfreezing temperatures for several months. Autumn months in wheat-growing regions typically experience significant rainfall. Hence, the wheat plants usually are exposed to freezing temperatures when they have high moisture content and are growing in very wet soil. Both of these conditions are conducive to freezing stresses different from those that occur under lower moisture conditions. This study was conducted to seek genetic variability among winter wheat lines and their progeny in the ability to tolerate freezing in saturated soil. Fully acclimated seedlings in saturated soil were frozen to a narrow range of temperature conditions that resulted in about 50% mortality of the most freezing tolerant lines studied. The temperature of the soil near the crowns of the plants was recorded every 2 min throughout each freezing episode. The following components were then determined for each freezing episode: the amount of time the plants remained in subfreezing temperature before all freezable water had been converted to ice; the rate of cooling from the freezing temperature to the minimum temperature; the minimum temperature; the length of time the plants remained at the minimum temperature; the rate of temperature increase from the minimum to 0 °C after freezing; and the total amount of time the plants were actually frozen. Partial regression analysis revealed the minimum temperature significantly influenced survival in all of the progeny populations, while the other five components significantly influenced survival in some, but not all of the populations, suggesting genotypic differences in the ability to tolerate variation in specific aspects of the freezing process. Evidence from progeny populations suggested that improved freezing tolerance was associated with decreased sensitivity to the length of time held at the minimum temperature and increased responsiveness to the post-freezing warming rate. Further analysis of this kind of variation may enable the genetic combining of sources of tolerance of the stresses imposed by specific components of the freezing process, leading to cultivars with improved tolerance of freezing in saturated soil.     

Effects of ultrasound-assisted freezing on the water migration of dough and the structural characteristics of gluten components

The effects of ultrasound-assisted freezing on the freezing time and water migration of dough, and the structural characteristics of gluten components were investigated. The effects of ultrasound-assisted freezing in the whole immersion freezing process (UWF) on the freezing time were better than those of ultrasound-assisted freezing in the maximum ice crystal generation zone. The shortest freezing time was obtained at 80 W/L, and was 577 s shorter than that with traditional immersion freezing. The UWF treatment at 80 W/L significantly (p < 0.05) affected the absorption enthalpy, freezable water content and water migration of frozen dough. In UWF compared with traditional immersion freezing, the SH content of gluten, glutenin and gliadin was significantly (p < 0.05) higher, by 12.06%, 27.55% and 21.65%, respectively. The surface hydrophobicity of gluten, glutenin and gliadin in UWF treated samples significantly (p < 0.05) decreased, by 19.67%, 13.21% and 9.17%, respectively. The secondary structure of gluten components was also significantly changed by UWF. The network of gluten, the chain structure of glutenin and the gliadin particles were all changed by UWF treatment. These findings indicated that UWF is an effective method to improve the moisture distribution in dough and reduce the damage to protein molecular structure caused by freezing.     

播种至苗期不同阶段冻害与持续时间对玉米幼苗建成及抗性生理的影响

以先玉335为供试品种，基于寒地典型玉米种植生态区的田间温度动态，采用两因素完全随机设计，分别设置冻害发生阶段和冻害持续时间处理，比较分析各处理组合条件下玉米幼苗形态建成及抗性生理指标的变化差异。研究表明，玉米播种至出苗各阶段发生冻害胁迫后，可不同程度延长玉米出苗时间、降低成苗率，甚至导致幼苗全部死亡。播后早期冻害通过降低种子贮藏物质转运效率，加剧膜脂过氧化，削弱叶片光能捕获能力等一系列不可逆影响，抑制幼苗形态建成，这些不利影响程度随冻害持续时间的延长而不断加强。播后冻害可诱导存活植株体内可溶性蛋白、脯氨酸、可溶性糖等渗透调节物质含量维持较高水平，以改善植株对低温环境的适应能力。玉米播种至出苗各阶段受冻害胁迫影响均较显著，且以播种10 d后植株对冻害最为敏感。     

Freezing Tolerance and Injury in Grapevines

Summary

Grapes, due to their wide distribution, are one of the temperate fruit crops most frequently damaged by freezing temperatures. Freezing injury can result in decreases in yield and substantial economic losses to grape growers, subsequently impacting fruit wholesalers, wineries, distributors, and related industries. Freeze damage is not limited to the northern or southern limits of the production range. Freezing injury can occur in spring, fall, or winter in many of the grape growing regions. An understanding of the mechanisms involved in freezing tolerance, acclimation, and deacclimation in grapevines is needed to match cultivars appropriately with growing sites, improve cultural practices that minimize freezing injury, and aid in breeding and selecting cultivars with improved freezing tolerance. The ability to avoid or tolerate freezing temperatures includes a complex set of traits that is influenced by the inherent genetic characteristics of the grapevine and its interaction with the environment. In the present review, the mechanisms of freezing tolerance in grapevines are summarized and discussed in relation to the influence of genotype, phenological development, and environmental factors.     

Increased Cell-Wall Mass and Resistance to Freezing and Snow Mold during Cold Acclimation of Winter Wheat under Field Conditions

Abstract

Accumulation of soluble carbohydrates plays an important role in enhancement of resistance to freezing and snow mold of plants during cold acclimation. Nevertheless, few studies have examined whether changes in cell wall properties are involved in enhancement of resistance during cold acclimation. In this study, four winter wheat cultivars were sown in a field on six different dates during August–October, and their resistance to freezing and snow mold were compared in relation to soluble carbohydrate content and cell-wall mass in leaves. Resistance to freezing and snow mold was much higher in the plants sown on 23 September than in those sown on 9 September. The percentage of cell-wall mass in leaf to total dry mass (%CW) and water-soluble carbohydrate content also increased considerably during 9–23 September. Multiple regression analyses revealed that %CW contributed significantly to freezing resistance, whereas total water-soluble carbohydrate content contributed significantly to snow mold resistance. These results suggest that increased %CW enhances freezing resistance during cold acclimation.     

6种草本药用植物种子超低温保存技术研究

以草本药用植物杜若、过江藤、夏枯草、皱果苋、罗勒和山香的成熟种子为材料,探讨了含水量和冷冻方法对种子超低温保存的影响。结果表明,经液氮超低温冷冻后,6种草本药用植物种子发芽率较对照组均有显著差异(p0.05);适宜的含水量下,种子经过超低温冷冻后其发芽率甚至高于对照组。3种冷冻方法中,玻璃化冷冻法更适合过江藤和山香种子的超低温保存,缓慢冷冻法更适合皱果苋、杜若和夏枯草种子的超低温保存,直接冷冻法适合于杜若和罗勒种子的超低温保存。所以,液氮超低温冷冻法保存杜若等6种草本药用植物种子是可行的;含水量对超低温保存前后夏枯草、山香和罗勒种子的发芽率影响显著。     

Changes in Freezing Tolerance and its Relationship with the Contents of Carbohydrates and Proline in Overwintering Centipedegrass (Eremochloa ophiuroides (Munro) Hack.)

Abstract

The objective of this study was to clarify the changes in the contents of endogenous carbohydrates and proline in the stolons and leaves of centipedegrass (Eremochloa ophiuroides (Munro) Hack.), during the natural cold acclimation (hardening) and de-acclimation (dehardening) in relation to freezing tolerance in the field at the transition zone between temperate and subtropical areas in China. The contents of carbohydrates and proline, and freezing tolerance estimated by LT₅₀, which is the temperature at which 50% of the electrolytes in the organ was measured in the leachate, were determined at 10-day intervals from October 1, 2001 to April 18, 2002. It was indicated that the freezing tolerance of stolons increased (LT₅₀ of stolons decreased) quickly, as temperature dropped before winter, but that of leaves which senesced along with the drop in temperature did not. The freezing tolerance of stolons decreased gradually along with the rise in temperature above 5 °C in spring, when the overwintered plants started to grow. The contents of proline and soluble carbohydrates, including sucrose, fructose and glucose, increased as LT₅₀ decreased when temperature dropped below 5 °C before winter, and decreased as LT₅₀ increased in early spring. Correlation analysis revealed that the freezing tolerance of stolons of centipedegrass significantly and positively correlated with the contents of proline and soluble carbohydrates, and the ratio of the soluble carbohydrates to starch. Thus, the freezing tolerance of stolons, which are critical organs that determine the winter surviving ability, largely depended on the content of soluble carbohydrates and the ratio of soluble carbohydrates to starch in centipedegrass. The possible relationship between freezing tolerance and carbohydrate metabolism was also discussed.