Bioactive compounds in rye flours with different extraction rates

Rye flours with extraction rate of 100% (wholemeal flour), 95% (brown flour), 90% (brown flour) and 70% (light flour) were prepared in order to study the relation between flour extraction rates and content of bioactive compounds. The following compounds were analysed: total phenolic compounds (TPC), total flavonoids (TF), inositol hexaphosphate (IP6), reduced (GSH) and oxidized (GSSG) glutathione, tocopherols (T) and tocotrienols (T3). The reduced/oxidized glutathione status (GSH/GSSG) of the flours was examined as a potential index of flour resistance against oxidative stress. The following observations were made in relation to the flour extraction rates and bioactive compounds contents: (a) milling process caused decrease in content in TPC, TF, IP6, GSH and GSSG, T and T3, (b) the most resistant against oxidation processes were suggested a brown flours, then light and finally wholemeal flour, (c) the ratio of tocotrienols to tocopherols (T3/T) was the highest in rye flours with extraction rate of 100–90% whereas light flour was the poorest source of tocopherols and tocotrienols. The provided data support current trend to increase number of rye products from wholemeal or brown flours.     

稻壳粉填充聚乙烯复合材料的研究

采用稻壳粉对高密度聚乙烯(HDPE)进行改性，研究了稻壳粉用量对。HDPE力学性能、耐热性、流动性及硬度的影响，并观察了稻壳粉在HDPE中的分散状况。结果表明：复合材料的弯曲强度、硬度、维卡软化温度随稻壳粉用量的增加而增加，而加工流动性能、拉伸强度、断裂伸长率和冲击强度则随稻壳粉用量的增加而下降；稻壳粉在HDPE中的分散不均匀，用量较大时易出现聚集现象，两相间的粘接性变差。     

The influence of oxidizing agents on water extracts of rye flour

The main constituents of rye flour extracts are proteins and pentosans. After cross-linking under the action of oxidizing agents those components are able to bind much more water than in their native (prior to modifications) state. As a consequence rheological properties of extract are changed.It was observed that kinematic viscosity of water extract of rye flour decreases rapidly with time. The reason for this behavior could be high enzymatic activity of flour extract.It was also found that the addition of hydrogen peroxide in the absence of additional peroxidase (which is naturally present in 1:9 or 1:1 water extracts of flour) causes the greatest increase in viscosity, due to the cross-linking of soluble polymers. Moreover after the addition of H₂O₂ to water extracts strong gels were obtained, which were characterized by tan δ = 0.5 (tan δ < 1). Moreover G′ was independent of frequency, which also suggests cross-linking of the pentosans.The addition of ascorbic acid, which is known to act preferably on gluten proteins, to 1:9 or 1:1 flour extracts had only a little effect on viscosity. In this case the values of tan δ = 0.9 were close to 1, which is typical for a weak gel.The application of inactivated rye flour extract, containing mainly proteins and pentosans, proved stronger effect of H₂O₂ in comparison to ascorbic acid on polymer cross-linking, but only after the addition of peroxidase. The gel obtained with H₂O₂ and peroxidase was also characterized by low tan δ = 0.4.The results indicate, that pentosans are the main subject of cross-linking reactions in rye flour water extracts.     

Physicochemical,nutritional and functional properties of marama bean flour

Marama bean is a protein-rich, underutilised, drought-tolerant legume in sub-Saharan Africa. Its utilisation may be increased through value addition into protein-rich flours. Defatted flour from unheated and dry-heated (150 °C/20 min) whole marama beans (UMF and HMF) were analysed for physicochemical and protein-based functional properties. Heating significantly increased in vitro protein digestibility of marama bean flour. Of functional importance are the high levels of tyrosine present in marama bean flours. Heating significantly reduced protein solubility and emulsifying capacity of marama bean flours whilst water absorption capacity was improved. Foaming capacity was not affected by heating. UMF could be useful in food systems requiring high emulsifying capacity, but would not be suitable for applications requiring high water absorption and foaming capacity. Due to its high protein contents, marama bean flour could be used to increase the protein quality of cereal-based foods to help alleviate protein-energy nutrition in the region.     

The physicochemical properties and in vitro digestibility of selected cereals,tubers and legumes grown in China

Digestibility, gelatinization, retrogradation and pasting properties of starch in various cereal, tuber and legume flours were determined. Rapidly and slowly digestible starch and resistant starch were present in 11 selected flours. In general, cereal starches were more digestible than legume starches and tuber starches contained a high amount of resistant starch. Thermal and rheological properties of flours were different depending on the crop source.     

Lupine,a source of new as well as hidden food allergens

The present review summarizes current knowledge about lupine allergy, potential sensitization routes, cross‐reactions between lupine and other legumes, and the respective IgE‐binding proteins. Since the 1990s, lupine flour is used as a substitute for or additive to other flours, mostly wheat flour, in several countries of the EU. In 1994, the first case of an immediate‐type allergy after ingestion of lupine flour‐containing pasta was reported. Since then, the number of published incidents following ingestion or inhalation of lupine flour is rising. So far, the Lupinus angustifolius β‐conglutin has been designated as the allergen Lup an 1 by the International Union of Immunological Societies Allergen Nomenclature Subcommittee. Initially, publications focussed on the fact that peanut‐allergic patients were at risk to develop anaphylaxis to lupine due to cross‐reactivity between peanut and lupine. At present, however, the ratio between cases of pre‐existing legume allergy (mostly peanut allergy) to de novo sensitization to lupine seed is nearly 1:1. Although in December 2006, lupine and products thereof were included in the EU foodstuff allergen list according to the Commission Directive 2006/142/EC amending Annex IIIA of Directive 2000/13/EC in order to prevent severe reactions caused by “hidden food allergens”, the majority of patients and medical personnel are still not aware of raw lupine seed as potentially dangerous food allergen.     

Repellency and some biological effects of different ultrasonic waves on Mediterranean flour moth,Ephestia kuehniella (Zeller) (Lepidoptera: Pyralidae)

Ephestia kuhniella is one of the most important stored pests in the world. Repellency and biological effects of various ultrasonic signals with different frequencies and wave shapes on adult, larvae and pupae of the pest were studied in laboratory conditions. Choice and non-choice tests was performed by an invented signal generator device. In choice tests, different ultrasonic frequencies, and for each frequency, four different waveforms were emitted by the device and numbers of repelled moths were separately calculated. Dispersion patterns, weight and survival of the pest treated by the ultrasound were compared with control in non-choice tests. The choice tests indicated that shape and frequency of ultrasound significantly affected evasive behavior of the moths by the waves. The highest repellency effects of ultrasound were observed at frequencies of 43–45 kHz and wave shapes of Sin (x) and Cos (x). Male moths significantly were more affected by the ultrasound. In non-choice test, weights of the pest larvae and pupae and the larvae survival were significantly reduced when they treated by ultrasound with frequency 40–45 kHz and Sin (x) wave shape that emitted by specific pattern. Also, our findings showed that the larvae and adults considerably tend to avoid from the ultrasound source. Results of the study can be applied for control of the pest in store locations or silage.     

Wheat-Legume Composite Flour Quality

Wheat-legume composite flours were produced by blending Canada Western Extra Strong (CWES) and Canada Western Red Spring (CWRS) wheat with varying amounts of three legume proteins. Legume protein addition produced breads with lower specific loaf volume, coarser crumb and firmer texture, and cooked white-salted noodles with greater compression stress and less cutting stress than the wheat controls. The CWES wheat compensated for the negative baking effects of the legume proteins as much as the CWRS wheat. End-use quality did not change at 2% soybean protein addition. Yellow pea protein produced the greatest quality changes, followed by chickpea and soybean protein.     

Chemical,rheological and parotta making characteristics of flourmill streams

Chemical, rheological and parotta-making characteristics of wheat-milling flour streams were studied with the main aim of developing a speciality flour for parotta. Important quality characteristics such as ash, flour colour, dry gluten content, sedimentation value, free and bound lipid content, farinograph and alveograph characteristics of the mill streams were determined. The studies showed an increase in ash, gluten content and sedimentation value with increasing numbers of breaks in the flour streams. An increase in percentage whiteness and bound lipids was observed in the first five reduction passages (C1 to C5). The alveograph characteristics indicated that the average abscissa at rupture (L) length of the curve increased with increasing reduction streams from C1 to C5, and also that the curves were better balanced when compared to 1 BK to 5 BK. The parottas made from the first five break passages had a decreased spread ratio, dull brown colour, and fused layers and lower overall quality score (43–79). The initial reduction streams (C1 to C5) produced good quality parottas in terms of appearance, spread, layers and texture. The shear force values indicating the texture of the product ranged from 1,120 to 1,250 g. The speciality flour made by combining C1 to C5 streams had 0.45% ash, 9.63% dry gluten, 45 ml sodium dodecyl sulphate sedimentation value, 0.7% free lipid and 1.8% bound lipid and produced parottas having creamish white colour, excellent pliability, thin, transparent and distinct layers, soft texture and moderate chewiness. In the mouth the parottas broke down easily, without leaving any residue. The overall quality score of parotta was highest (93.5) for the speciality flour when compared to break and reduction streams (43–77 and 56–92 respectively).     

超微粉碎面粉的蛋白质变化探讨

采用自行设计制造MFT-300型机械冲击式粉碎机对面粉进行粉碎加工、分级，通过工艺参数调整，选出两种加工分级后的产品进行分析，结果表明：加工后的面粉平均粒径可达5.98μm，形貌呈球对称状：其蛋白质含量随粒径变细而增加，当D90小于10μm时，蛋白质含量骤然增大一倍多，从而为面粉的特殊使用要求提供了深加工的途径。