Use of biocides for the control of fungal outbreaks in subterranean environments: the case of the Lascaux Cave in France

The Lascaux Cave in France suffered an outbreak of the fungus Fusarium solani in 2001. Biocides were applied for three years to control this outbreak. Four months after the initial biocide application, a new outbreak appeared in the form of black stains that progressively invaded the cave. The black stains on the ceiling and passage banks were so evident by 2007 that they became one of the cave's major problems. Therefore, biocides were used again in 2008. The present study investigated the fungal communities associated with the black stains and the effectiveness of the biocides applied, by using cloning, denaturing gradient gel electrophoresis, and culture-dependent methods. A novel species, Ochroconis lascauxensis, was the most abundant fungus in samples collected between 2007 and 2008, and the biocides applied were not effective in eliminating this fungus; on the contrary, they appeared to increase the fungal diversity. The fungal communities represented in the samples collected in 2010 were quite different from those collected in 2008 and 2009: the major OTUs corresponded to black yeasts belonging to the Herpotrichiellaceae family. The origin and evolution of these microorganisms are probably linked to the intensive biocide treatments and to the anthropogenic changes introduced by cave management.     

进口樟子松的变色及预防和控制

分析了木材变色的原因和进口樟子松变色现象,结合生产实践,提出了几种预防和控制樟子松变色的方法。     

面粉厂配粉控制系统的研究

根据小麦粉后处理过程中用配粉仓进行称重式配粉的工艺流程,构建了计算机自动配粉控制系统.该控制系统可实现对整个配粉过程的自动控制,自动控制多种基础粉按照一定的配方比例混合搭配,完成自动入仓、自动倒仓、仓容信息显示、设备运行监控、人机交互、配方管理、报表统计等功能.     

Heat combined with diatomaceous earth to control the confused flour beetle (Coleoptera: Tenebrionidae) in a flour mill

An alternative to methyl bromide fumigation for controlling stored-product insects in food processing facilities is to heat part or all of a facility to 50-60°C for 20-30 h. However, some equipment or structures cannot tolerate these conditions, or it is difficult or expensive to attain these high temperatures. It may be possible to reduce the temperature requirements necessary for effective control by using a desiccating dust, such as diatomaceous earth (DE), in combination with the heat treatment. The objectives of this study were to examine the combined impact of high temperature and DE on the mortality of Tribolium confusum (du Val) in a flour mill environment and to evaluate the effects of DE application rate on insect mortality in a mill environment during heat treatment. In areas of the mill where temperatures were in excess of 47°C, DE applications of 0.3 g/m² in combination with heat were no more effective than the heat treatment alone. At higher application rates, the DE was more effective. In cooler areas, adult beetles exposed to DE died sooner than insects not exposed to the insecticidal dust. These results indicate that application of DE in areas that cannot be heated to 47°C is effective for controlling T. confusum in a flour mill. A comparison is made with a parallel study conducted in Canada.     

Towards the development of peanut–wheat flour composite dough: Influence of reduced‐fat peanut flour on bread quality

The effect of partial substitution of wheat flour with reduced‐fat peanut flour at different levels (10, 20, 30, 40, and 50%) on physical parameters, proximate composition, sensory profile, and shelf stability of bread were investigated. Loaf volume, specific volume, and crumb density were significantly (p ≤ .05) reduced with increasing level of substitution with the peanut flour. Peanut flour had significant (p ≤ .05) improvement on the protein content and reduction in carbohydrate content of loaves. Consumers preferred the taste aroma and color of the peanut–wheat flour composite loaves at ≥20% peanut flour inclusion. Freshly baked composite peanut–wheat bread loaves with 10% level of peanut substitution had higher overall acceptability than 100% wheat flour formulation but less microbial stability during storage. Reduced fat‐peanut has potential application for improving the nutritional quality and shelf stability of wheat flour bread.

Practical applications

The demand for convenient alternative to conventional foods is on the increase with the dynamics of the world's social values, lifestyles, and demographic trends. Having peanut incorporated into dough (as one food system) will offer convenience to consumer and therefore add value to bread variety on market shelves. Assessing the influence of the peanut flour on bread quality provides first‐hand information that can facilitate optimization of the baking process toward commercial production of peanut–wheat flour bread.     

Properties of laminated veneer lumber (LVL) made with low density hardwood species: effect of the pressure duration

Cross-linked polyvinyl acetate (PVAc) adhesive and thin veneers of three low density wood species, namely silver maple, yellow poplar and aspen, were used to produce LVL engineered wood products using different press durations. Density, water absorption, thickness swelling, flexural strength and surface hardness were evaluated. Internal bond strength, tensile shear and block shear strengths were tested in dry, accelerated (boiling and dry) and cyclic (wet and dry) conditions. LVL made using cross-linked polyvinyl acetate and silver maple with a platen temperature of 38 °C for 5 minutes exhibited the best properties. LVL of silver maple veneers showed improved properties as compared to yellow poplar and aspen. Silver maple can be used suitably in laminated veneer flooring.     

Microwave radiation for control of Tribolium confusum in wheat and flour

The susceptibility of Tribolium confusum Jacquelin du Val to microwave energy was determined by irradiating vials of infested wheat or flour near the aperture of an optimum gain horn coupled through a waveguide to a magnetron operating at 8·5 GHz and 30 W average output at a pulse repetition frequency of 4000 Hz. Mortality was a function of exposure time and wheat moisture content. Adult mortality was higher in insulated samples of wheat than in non-insulated samples. Susceptivility of stages to radiation at 60°C was: eggs > pupae > adults > larvae. Survival of pupae near the surface of wheat indicated that heat was distributed non-uniformly. Mortality was higher in wheat than in white flour. Adults from 1·5 to 7 months old were equally susceptible to radiation.     

Improving the nutritional quality and maintaining consumption quality of akara using curdlan and composite flour

Soybean flour and curdlan were incorporated into cowpea flour to determine their effect on lowering the fat content and on the physical properties of akara. At 20% substitution, soybean flour lowered the fat content of akara by 7.7% and increased the protein content by 28.7% without significantly affecting the firmness or the colour of akara. Addition of 1% curdlan decreased the fat content by 32.2% but significantly increased the firmness of akara and produced a darker‐coloured product. The paste moisture content of akara containing 20% soybean flour and 1% curdlan was modified to obtain product characteristics comparable with the control (100% cowpea flour) while maintaining a lower fat content. Optimum results were obtained for paste with 63% moisture content. Firmness of this modified product was similar to the control and the fat content was lower (17%) compared with the control (26%).     

鹰嘴豆粉对面团流变学特性及面条品质的影响

鹰嘴豆含有大量蛋白质及不溶性膳食纤维,脂肪含量低,有益于人体健康并受到广大消费者的喜爱。但鹰嘴豆粉应用于面条及其对面条品质的影响尚不清楚。该研究将鹰嘴豆粉以一定比例与小麦粉混合,研究了鹰嘴豆粉含量对面团的流变学特性、面条的烹煮特性及质构特性的影响。结果表明:鹰嘴豆粉与小麦粉质量比小于2∶8时,对面团流变学特性及面条品质的影响较小;随着鹰嘴豆粉添加比例增加,面团更易流变且加工性能明显下降,面条的熟断条率显著增大,质构性能变差。鹰嘴豆粉与小麦粉质量比为1∶9时,魔芋精粉、食盐和水的添加量分别为0. 5%、0. 5%和35%(占鹰嘴豆粉和小麦粉的总质量)。使用该工艺生产的面条不仅含有鹰嘴豆特殊宜人的豆香味,同时改善了传统面条的营养品质。     

Effects of two fumigants and a fungicide formulation on the development of kiln brown stain in radiata pine lumber

Two fumigants (methyl bromide and sulphuryl fluoride) were used to treat freshly sawn radiata pine (Pinus radiata D. Don) lumber and log sections to evaluate their influence on development of kiln brown stain. Both treatments reduced severity of stain when compared with controls. The sulphuryl fluoride treatment was notably better than methyl bromide at the highest fumigant dosage, but levels of overall stain were still considered unacceptable with only 20–30% of lumber having either no or slight stain beneath the surface. Sulphuryl fluoride showed superior penetration into sapwood compared to methyl bromide as determined by a colour assay of parenchyma cell viability. A fungicide formulation which was successful in preventing brown stain in kiln dried eastern white pine was ineffective against kiln brown stain in radiata pine. The results of the present study indicates that the mechanism for kiln brown stain in radiata pine differs from that in eastern white pine.     

真菌α-淀粉酶和麦芽糖α-淀粉酶对馒头粉品质改良的比较研究

从提高小麦粉质量、延长馒头货架期的角度出发,以国产小麦粉作为试验用粉,通过粉质试验、降落数值测试、蒸馒头试验及质构测试等分析方法,研究了真菌α-淀粉酶和麦芽糖α-淀粉酶在国产小麦粉中发挥改良作用的应用效果。结果表明:真菌α-淀粉酶对馒头粉综合品质的提高优于麦芽糖α-淀粉酶,而麦芽糖α-淀粉酶在馒头贮存过程中的抗老化效果优于真菌α-淀粉酶。     

Effect of fungal α-amylase on the dough properties and bread quality of wheat flour substituted with polished flours

Whole grains of a hard-type wheat cultivar ‘1CW’ (No. 1 Canada Western Red Spring) were polished from the outer layer to the inner layer by 10% of the total grain weight using a modified rice-polisher. The polished flours of three fractions; C-1, C-5, and C-8 corresponding to 100–90%, 60–50% and 30–0% layer of the 1CW grain, respectively were used in this study. Effects of fungal α-amylase on polished flour substitution for the common wheat flour CW of 1CW on rheological or physicochemical dough properties and bread qualities were studied. When the polished flours were substituted for CW without fungal α-amylase, the mixing tolerance index of dough in a farinograph and all parameters of viscoelastic properties significantly increased rather than those of CW alone. As a result, baking qualities of breads made from the substituted flours were significantly inferior. But, the polished flours increased the total gas generation significantly during fermentation, as compared with CW alone. The addition of fungal α-amylase to polished flour substituted CW distinctly developed gluten matrix in the SEM images and produced large amounts of the generated gas during fermentation. Therefore, the loaf volume and firmness of breads were improved by the combined additions of polished flours and fungal α-amylase. Especially, the C-8 of the innermost fraction was more susceptible to affection of fungal α-amylase among all polished flours, and resulted in improvement of gas cell distribution and softness of breadcrumbs without lowering the loaf volume as compared with CW bread.     

我国糯米粉加工及其质量控制技术现状与展望

综述了糯米制粉技术及其对糯米粉品质和理化特性的影响,分析了加工过程中糯米粉原料、在制品和成品的质量检验与控制技术,可为糯米粉加工、利用和产业发展提供技术参考.     

高效液相色谱法测定小麦粉及其制品中间苯二酚

建立一种利用高效液相色谱测定小麦粉及其制品中间苯二酚含量的方法。样品经甲醇提取,亚铁氰化钾和乙酸锌沉淀,经C₁₈-Amide柱分离,甲醇/水为流动相洗脱,二极管阵列检测器与荧光检测器串联检测,外标法定量。二极管阵列和荧光检测器的定量结果均具备良好特异性,且在各自线性范围内r^₂＞0.999,定量限分别为1 mg/kg和0.05 mg/kg,回收率在73.0-108.6%之间,RSD<8.2%。建立的方法操作简单、灵敏度高、准确度好,适用于小麦粉及其制品中间苯二酚的测定。     

加工魔芋粉褐色素控制研究进展及问题

色素对食品加工品质具有重要影响,如何对其进行控制以保证产品色泽、性能等品质是研究重点。针对魔芋粉加工中产生褐色素问题,该文综述对褐色素控制研究进展及存在问题,并对其研究方向提出展望和建议,以期为食品色素研究、提高产品品质提供参考。     

Changes of chemical composition and dough rheology in two fractions of sieve-classified Polish spring wheat flour

The study of chemical composition and dough rheology changes in sieve-classified two fractions (up to 60 and 60-240 microm particles) of wheat flour was the subject of this study. The straight grade flours were obtained by the milling of three Polish varieties of spring wheat, differing in particle size index (PSI) values. The flours were separated with the use of an SZ-1 laboratory sifter. The yield of fine fraction was in the range 50.0-55.7%. The obtained fractions were assayed for the content and composition of free lipids, gluten proteins, damaged starch, ash, water absorption and amylograph viscosity. Dough rheology (extrusion in OTMS cell, alveograph and farinograph tests) and baking trials were also performed. The content of free lipids, including the non-polar and phospholipids was lower and the content of glycolipids was higher in fine flours. Those fractions were more rich in linoleic acid but the lower content of oleic and linolenic acids resulted in a higher oxidizability index of free lipids. Fine flours contained less ash and significantly more damaged starch. At the same time, they were characterized by a higher content of wet gluten, water absorption, amylograph viscosity and better dough parameters. This was reflected in the bread volume, which was higher by 6.3-10.7%. The influence of the changes in composition and the content of free lipids upon the rheology of the dough after the 90 days flour storage has not been defined unambiguously and requires further research.     

Nutrients and antinutrients in cowpea and horse gram flours in comparison to chickpea flour: Evaluation of their flour functionality

The nutrient composition, antinutritional factors and flour functionality of cowpea and horse gram flours were evaluated in comparison to chickpea flour characteristics. Protein content of these flours was in the range of 22.5−24.1%. Fat content was highest in chickpea (4.8%) and lowest in horse gram (1.4%). Resistant starch and phytic acid were significantly higher in cowpea flour. Compared to chickpea and cowpea, horse gram has more carbohydrate, dietary fibre, polyphenols and trypsin inhibitor activity and less oligosaccharides. Horse gram and chickpea flours had the highest water and oil absorption capacities with values of 148.1% and 109.3%, respectively. Although emulsion activity (58.1%) and stability (52.0%) were superior in horse gram, foaming capacity and foam stability were significantly higher in chickpea and cowpea flours, respectively. These results suggest the potential utility of cowpea and horse gram flours as substitutes for chickpea flour in some food products formulations.