Optimisation of rheological properties of gluten-free doughs with HPMC,psyllium and different levels of water

Hydrocolloids have traditionally been investigated as an alternative to gluten for making good quality products for coeliac patients. This study investigated the interactions between hydroxypropylmethylcellulose (HPMC) (2–4 g/100 g of flour), psyllium (0–4 g/100 g of flour) and water level (90–110 g/100 g of flour) in gluten-free breadmaking. Psyllium incorporation reduced the pasting temperature and compliance values, and increased elastic (G′) and viscous (G″) moduli values. In contrast, HPMC addition had no important effects on pasting properties and compliance values, but also increased G′ and G″ values. Psyllium inclusion reduced bread specific volume and increased bread hardness, while there were hardly differences in the bread specific volume and hardness between the percentages of HPMC studied. In addition, when the dough hydration level was increased, there was a decrease in the influence of hydrocolloids on dough rheology and specific volume and hardness of breads.     

Discrimination of bark from wood chips through texture analysis by image processing

Utilization of wood chips for bioenergy requires classification and segregation of the constituents of the chipped mass to help optimize energy conversion. Wood chips obtained from processes such as forest thinning can contain a considerable amount of material other than wood chips, such as bark. An image processing algorithm was developed to discriminate bark from wood chips. The algorithm involved object identification, image capture, single value decomposition to describe wood texture evident in grayscale image with a single numerical value, and application of logistic models involving the single values representative of wood texture to predict whether a chip is bark. The percentage of correct predictions using this system was about 98%.     

Detecting fruits in natural scenes by using spatial-frequency based texture analysis and multiview geometry

This paper describes a computer vision based model for object detection that can serve as a preliminary step in fruit prognosis, which involves the estimation of the number, diameter and yield of apple fruits. In order to overcome the recognition unreliability in uncontrolled environments caused by uneven illumination conditions, partly occluded surfaces, and similar background features, we rely on a combination of the object's colour, texture and 3D shape properties. In our research, we apply colour segmentation to multiple scene snapshots to separate potential regions from the background and verify them first with texture analysis and second by reconstructing them to 3D space. By analysing all three distinct features (colour, texture and 3D shape) of possible areas, we can safely conclude if they represent fruits we are looking for. Once we detect and verify all areas representing fruits, we can measure their size and model estimated fruit yield.     

高杆白菜粗纤维含量对皖南"香菜"品质的影响

[目的]研究高杆白菜中粗纤维含量,为筛选"香菜"加工原料提供参考。[方法]以4个不同地区的高杆白菜品种及来自同一品种的3个品系的高杆白菜为试材,比较了不同品种高杆白菜鲜品粗纤维含量并用质构仪对其硬度进行测定。[结果]JX品种的高杆白菜粗纤维含量最低,为12.63%,LSD法检验得出其与其他3个品种的粗纤维含量差异均显著,且硬度较高,适合加工。以JX作为原料,对其进行处理、倒缸、拌料后装瓶,监测其装瓶后28 d内粗纤维含量,在第4天和第12天出现2个峰值,其硬度曲线随时间变化呈下降趋势。[结论]高杆白菜中粗纤维含量可作为筛选"香菜"加工原料的依据之一。     

北方馒头品质评价方法的比较

【目的】馒头品质是中国小麦改良的重要目标,准确性高、重复性好的评价方法是有效进行遗传改良的前提和基础。本文目的为研究实验室北方馒头品质评价方法。【方法】25个不同筋力小麦品种分别种植于黑龙江、宁夏、新疆和甘肃,采用机制方法加工北方馒头,用国标GB/T17320-1998和澳大利亚面包研究所(BRI)馒头品质评价方法进行品质评分,以比较2种馒头品质评价方法的异同。【结果】BRI评价方法中的压缩张弛性(SR)与国标馒头评分中体积、比容、弹性及总评分呈正相关(r=0.60—0.72),可作为馒头品质评价的有效指标。BRI总评分与国标总评分均呈显著正相关(r=0.66,P0.01),但其总评分值相对较低。【结论】BRI馒头品质评价方法能更好区别不同筋力馒头品质间的差异,且较为客观、易操作,可以用来有效评价中国北方馒头。质构仪压缩张弛性可以较好地反映馒头的适口性,能对馒头品质进行客观量化评价。基于国标和BRI方法,研究提出了新的馒头品质评价标准。     

鲜切冬瓜贮藏过程中质构品质变化分析

应用质构仪对鲜切冬瓜贮藏过程中的质构品质进行研究,旨在为鲜切冬瓜的生产和销售提供理论依据和技术指导。结果表明,混合保鲜液处理有效地延缓了鲜切冬瓜的硬度、弹性、咀嚼性的下降;质构指标的变化客观地反映了鲜切冬瓜的品质变化,质构指标可以用于衡量和评价鲜切冬瓜的品质。     

密集烘烤过程中烤烟细胞生理和质地变化

采用河南农业大学设计的电热式温湿自控密集烤烟箱,以中烟100上部叶为材料,研究了烘烤过程中烟叶细胞生理和质地变化的规律。结果表明,烘烤中烟叶的呼吸强度在38℃时达到高峰,箱内CO₂含量为1.80%,48℃以后烟叶的呼吸作用减弱。烘烤中果胶酯酶和纤维素酶在38~54℃活性较高,其中果胶甲酯酶(PME)和纤维素酶活性42℃最高,多聚半乳糖醛酸酶(PG)活性48℃最高,PG与PME共同促进了原果胶的水解进程,烘烤中原果胶、总果胶和纤维素含量不断降低。烟叶质地(除黏聚性)在38~48℃之间发生显著变化,其中42℃硬度和咀嚼性值最大,38℃拉力和剪切力值最大,48℃黏聚性、拉力和剪切力值最小。相关分析表明,可溶性果胶与回复性呈显著负相关(P<0.05);原果胶、总果胶及纤维素与回复性、拉力均呈显著或极显著正相关(P<0.05)。这些结果说明烘烤过程中烟叶质地的绵软在某种程度上是细胞壁物质不断降解的结果。研究表明,烘烤中烟叶剪切力的动态变化较为直观,回复性和拉力可以作为探讨烟叶细胞生理变化的参数,而烟叶细胞生理变化是导致质地差异显著的主要因素。     

Seed coat texture,host species and time of application affect the efficacy of essential oils applied for the control of Callosobruchus maculatus (F.) (Coleoptera: Bruchidae) in stored pulses

The effects of the texture of seed coats of three pulse cultivars, of which two, TVu12349 (wrinkled cowpea) and Borno brown (rough cowpea) belonged to Vigna unguiculata, and one, Bunmonu (smooth bambara groundnut) belonged to Vigna subterranea, as well as pre-and post-oviposition application on the efficacy of the essential oils of clove (Syzgium aromaticum), West African black pepper (WABP) (Piper guineense) and ginger (Zingiber officinale), against oviposition and development of Callosobruchus maculatus, were investigated under prevailing storage conditions (32-35°C and 40-50% RH) and 24 h darkness in Maiduguri, Nigeria. Seed coat texture influenced the bioactivity of the essential oils, especially clove oil, against oviposition and the proportion of C. maculatus adults that emerged significantly more than host species: the mean numbers of eggs laid on the smooth-seeded Bunmonu, the rough-seeded Borno brown and the wrinkled TVu12349 were 16.9, 16.7 and 24.2%, respectively; adult emergence was 31.1% in the wrinkled TVu12349, 45.3% in the rough-seeded Borno brownand 10.2% in the smooth-seeded Bunmonu. The smooth-seeded Bunmonu reduced oviposition in seeds treated with clove oil by 91.4% and 98.4% relative to the mean number of eggs laid in the rough-seeded and the wrinkled Tvu12349, respectively; comparable figures of oviposition reduction by Bunmonu in untreated seeds were 4.8 and 15.9% relative to the mean number of eggs laid in Borno brown and Tvu12349, respectively. Both pre-and post-oviposition application of the essential oils significantly suppressed oviposition and/or adult emergence. In the pre-oviposition application, treatment of bambaranut seeds with clove, WABP and ginger oils at the rate of 1 mg/5 g seed reduced the mean number of eggs laid by C. maculatus by 70.7, 98.7 and 86.2%, respectively, relative to the number of eggs laid in untreated seeds. Post-oviposition treatments were, however, more effective on average, than pre-oviposition treatments in reducing the proportion of C. maculatus adults that emerged. In the post-oviposition application, no adult C. maculatus emerged in bambaranut seeds treated with clove oil at the rate of 0.5 or 1 mg/5 g seed.     

TPA测试法分析不同保鲜剂对‘克瑞森’无核葡萄质地的影响

【目的】为了探究不同保鲜剂处理的‘克瑞森’无核葡萄贮藏过程中的质地变化,以及各质地参数的相关性,【方法】以天津市茶淀镇出产的‘克瑞森’无核葡萄为试材,并通过质地多面分析法定期测定质地参数。【结果】结果表明:各处理的硬度与咀嚼性总体呈现下降趋势;而除对照外,其余处理的弹性、凝聚性、回复性呈先下降后升高的趋势。另外,‘克瑞森’葡萄果肉硬度与黏着性、弹性、凝聚性、回复性均呈负相关,而与咀嚼性呈显著的正相关;弹性与咀嚼性呈较好的负相关性;凝聚性与回复性呈极显著的正相关性,而且黏着性与弹性、回复性呈正相关性。【结论】不同保鲜剂保持‘克瑞森’无核葡萄贮藏过程中的质地效果明显,且各处理之间存在差异。     

Effect of soil salinity and sodicity on Matricaria chamomilla,L. Growth

Abstract

Growth response of Matricaria chamomilla, L. was investigated on a range of soil salinity and sodicity levels using fine and coarse‐textured soil types. Twenty treatments including 4 levels of salinity and 4 levels of sodicity on each soil type were examined in addition to control. On the coarse‐textured soils, chamomile responded best under relatively low saline and sodic conditions. Plant growth decreased with increase in salinity and sodicity. On the fine‐textured soils, plants endured saline conditions up to 13 ECe and grew better under sodic conditions. The best growth of plants was achieved on fine‐textured soils with sodicity level of 31.8 Esp.