Co-occurrence of type A and B trichothecenes and zearalenone in wheat grown in northern Italy over the years 2009–2011

The occurrence of the most widespread type A and B trichothecenes and of zearalenone was surveyed in soft and durum wheat produced in northern Italy. A total of 293 wheat fields, grown in the years 2009–2011, were surveyed; for each field, weather and cropping system data were collected. The results indicated a high deoxynivalenol incidence, with durum always more contaminated than soft wheat; in 2010, the percentage of durum wheat samples exceeding the European Commission legal limit was 39.6%. As regards type A trichothecenes, widespread contamination was observed in 2010. In soft wheat, an incidence of 70% and 85% was found for T-2 and HT-2 toxins, respectively; all the durum wheat samples were contaminated. The trichothecene contamination was affected by weather conditions; copious rainfall and high relative humidity (RH) during flowering occurred in 2010, when the highest contamination of both type A and B trichothecenes was found.     

Variability of wheat and other cereal water extract viscosity. 2 – Range and causes of variation

Water extract relative viscosity of 502 common wheat, 9 maize, 3 sorghum, 21 durum wheat, 36 triticale, 7 oat and 58 barley samples grown in France were measured. Water extract viscosity in wheat is higher than in maize and sorghum, slightly lower than in triticale and much lower than in most barleys. Variability of the relative viscosity for wheat extracts was mainly explained by varietal differences. The effect of the production location was less important and seemed to be partly explained by drought. Apart from irrigation, neither the differences in production methods (such as crop protection, nitrogen fertilization and date of sowing), nor sprouting nor storing had any effect on relative viscosity. © 1999 Society of Chemical Industry     

Spaghetti making potential of Indian durum wheat varieties in relation to their protein,yellow pigment and enzyme contents

The research was carried out to evaluate spaghetti making potential of 12 Indian durum wheat varieties in relation to their protein and yellow pigment content and peroxidase, polyphenol oxidase, lipoxygenase, and protease activities. The protein content of the durum wheat varieties varied from 12.1% to 15.9% and their yellow pigments content ranged from 3.8 to 7.2 ppm. The peroxidase activity in these wheat varieties varied from 269 to 1010 U/g and polyphenol oxidase activity from 58.8 to 78.3 U/g. The lipoxygenase activity of durum wheats ranged between 1.44 and 6.88 U/g. Protease activity was in the range of 1.1–5.1 U/ g. The data for varieties MACS-1967, MACS-3125, MACS-2846, DWR-2006, HI-8498 and N-59 were indicative of their potential for the preparation of pasta products.     

无机盐对小麦胚芽脂肪酶结构和活性的影响研究

摘 要：为探索一种新型的小麦胚芽稳定化方法,本文采用圆二色谱和荧光光谱对无机盐处理后的商品化麦胚脂肪酶的结构进行了研究,同时,考察了不同无机盐对麦胚中脂肪酶活力及麦胚酸价的影响。研究结果表明,当NaCl浓度为4×10-9 mol/L时,对商品化麦胚脂肪酶的抑制效果最好,其活力降低了21.8%,而KCl对脂肪酶的活力无显著影响,CaCl2和MgCl2均对脂肪酶有激活作用;所选无机盐对脂肪酶二级结构均无明显影响,但NaCl对脂肪酶的三级结构有一定影响;当添加无机盐后,麦胚中的脂肪酶活力和麦胚的酸价均低于未添加无机盐的麦胚,其中1.30%NaCl使脂肪酶活力降低了62.49%,0.75% KCl使脂肪酶活力降低了61.27%。由以上结果可知,添加无机盐可作为有效抑制脂肪酶的活力的手段,利于延长麦胚的贮藏期。     

微波联合酶法对小麦麸皮品质改良及结构特性影响

本研究以小麦麸皮为原料,采用正交实验优化微波联合酶解对小麦麸皮品质改良工艺参数,并对比分析微波、酶解、微波联合酶解三种处理方式对小麦麸皮结构和性质的影响。研究发现:小麦麸皮微波联合酶解的最佳工艺参数为:微波功率700 W,时间15 min,料水比1:4,木聚糖酶添加量0.4 g,纤维素酶添加量0.4 g,酶解时间4 h,酶解温度60 ℃,此时小麦麸皮中还原糖含量为25.15 mg/mL。小麦麸皮经微波联合酶解处理后,持水性增加了30.18%,植酸含量降低了70.46%,持油性降低了26.69%,脂肪酶(LA)残余酶活降低至6.13%,粗纤维含量降低至2.79%,还原糖含量上升至25.15 mg/mL。傅里叶变换红外光谱分析结果表明微波联合酶解可以破坏分子间的糖苷键,使小麦麸皮细胞壁中纤维素、半纤维素降解,生成小分子的还原糖。扫描电子显微镜观察结果显示微波联合酶解破坏了小麦麸皮结构,使得麸皮表面变粗糙,结构疏松多孔。通过本实验改性的麦麸中脂肪酶残余酶活显著下降,麦麸食用品质明显改善。     

Effect of thermal processing on phenolics, antioxidant activity and health-relevant functionality of select grain sprouts and seedlings

The effect of thermal processing via autoclaving on modifications of total phenolics, antioxidant activity and functionality of wheat, buckwheat, corn and oats sprouts and seedlings were investigated. Functionality for type 2 diabetes related α-amylase, α-glucosidase inhibition and levo-dihydroxy phenylalanine (l-DOPA) content, hypertension related angiotensin converting enzyme 1 (ACE) inhibition and ulcer related Helicobacter pylori inhibition were evaluated using in vitro assays. Thermal processing in general resulted in tissue browning leading to higher total phenolic content and free radical scavenging-linked antioxidant activity. It increased α-amylase inhibitory activity in buckwheat and oats but decreased in wheat and corn sprouts and seedlings. It increased α-glucosidase inhibitory activity in wheat, buckwheat and oats but decreased in corn sprouts. It reduced the cognitive function/diabetes related l-DOPA content in all grains sprouts and seedlings tested. It increased ACE inhibitory activity in buckwheat and oats, but decreased in wheat and corn sprouts. It also improved the ulcer related H. pylori inhibitory activity in all grain sprouts and seedlings studied. These changes in functionality are suggested to be due to modifications in the total phenolic content and profile by phenolic oxidation or polymerization caused by thermal processing. Therefore, diet designs for chronic disease management will have to consider thermal processing-linked modification of bioactive ingredient profiles.

Industrial relevance

Thermal processing altered the total phenolic content and antioxidant activity in winter wheat, buckwheat, corn and oats sprouts and seedlings. It modified the α-amylase inhibitory activity, α-glucosidase inhibitory activity, l-DOPA content, ACE inhibitory activity and H. pylori inhibitory activity of samples. Therefore, the food processing industry and diet design for chronic disease management will have to consider thermal processing-linked modification of bioactive ingredient profiles for more effective health benefits.     

Antioxidant activity and dietary fibre in durum wheat bran by-products

Milling of wheat generates by-products, which can be used to improve the technological performance and/or to integrate foods with healthy compounds. The aim of this paper was to select fractions of durum wheat bran having different functional and nutritional characteristics. Wheat bran by-products were obtained by an industrial milling process. Beside the single fractions, two commercial products Bran & Brain 50 and 70, obtained by blending some of the durum wheat fractions were also studied. All samples were investigated for water holding capacity, soluble and insoluble dietary fibre content and for their antioxidant activity. The soluble fibre content of the durum wheat by-product ranged between 0.9% and 4.1%; while that of insoluble fibre between 21% and 64%. B&B 70 has a TDF content of 61%, while B&B 50 has 42%. The water holding capacity of each fraction is strictly related to the amount of insoluble fibre and to the granulometry of the by-products. Cooking-extrusion process does not affect the amount of soluble fibre; by contrast, a significant increase of the insoluble fibre was detected. The antioxidant activity is higher for the internal bran fraction and it increases in fractions having reduced granulometry. The antioxidant activity of some durum wheat by-product fractions is comparable to that of widespread fruits and fresh vegetables, likely due to the presence of fibre-bound phenol compounds. The high fibre content and antioxidant activity of durum wheat bran by-products can be of particular interest for their use in cereal-based products.     

Bread and durum wheat compared for antioxidants contents,and lipoxygenase and peroxidase activities

Potential beneficial components, including proteins, total phenolics, total flavonoids, carotenoids, tocopherols, and DPPH radical scavenging activity, were investigated in wholemeal of ten bread (T. aestivum L.) and ten durum (T. durum Desf.) novel wheat genotypes. In addition, the activity rate of lipoxygenase (LOX) and peroxidase (POD) enzymes implicated in the antioxidant metabolism was determined. The protein contnet and the antioxidant properties varied according to the two different wheat species, as well as, between the different bread and durum wheat genotypes themselves. The results indicated significant differences in proteins and antioxidant compounds between bread and durum wheat. Higher total proteins, wet gluten and antioxidants contents, combined with lower LOX and POD activities, point to a higher nutritive value of durum wheat than bread wheat.     

茯砖茶多酚类物质对胰脂肪酶活性的抑制作用

以湖南茯砖茶为原料通过热水浸提、树脂吸附分离得到茯砖茶多酚类物质,并采用酶动力学和荧光猝灭分析方法探讨了茯砖茶多酚类物质对胰脂肪酶的抑制作用。结果表明：茯砖茶多酚类物质对胰脂肪酶有抑制作用,半抑制浓度（IC50）为0.81 mg/mL,抑制类型为可逆非竞争性抑制,其抑制常数Ki为2.56 mg/mL。荧光光谱分析表明茯砖茶多酚类物质对胰脂肪酶具有荧光猝灭效应,与茯砖茶多酚类物质的结合可能造成了酶结构的改变,从而降低了酶的催化活性。     

Effect of Sorghum Flour Addition on In Vitro Starch Digestibility,Cooking Quality,and Consumer Acceptability of Durum Wheat Pasta

Whole grain sorghum is a valuable source of resistant starch and polyphenolic antioxidants and its addition into staple food like pasta may reduce the starch digestibility. However, incorporating nondurum wheat materials into pasta provides a challenge in terms of maintaining cooking quality and consumer acceptability. Pasta was prepared from 100% durum wheat semolina (DWS) as control or by replacing DWS with either wholegrain red sorghum flour (RSF) or white sorghum flour (WSF) each at 20%, 30%, and 40% incorporation levels, following a laboratory‐scale procedure. Pasta samples were evaluated for proximate composition, in vitro starch digestibility, cooking quality, and consumer acceptability. The addition of both RSF and WSF lowered the extent of in vitro starch digestion at all substitution levels compared to the control pasta. The rapidly digestible starch was lowered in all the sorghum‐containing pastas compared to the control pasta. Neither RSF or WSF addition affected the pasta quality attributes (water absorption, swelling index, dry matter, adhesiveness, cohesiveness, and springiness), except color and hardness which were negatively affected. Consumer sensory results indicated that pasta samples containing 20% and 30% RSF or WSF had acceptable palatability based on meeting one or both of the preset acceptability criteria. It is concluded that the addition of wholegrain sorghum flour to pasta at 30% incorporation level is possible to reduce starch digestibility, while maintaining adequate cooking quality and consumer acceptability.     

The polypeptide composition,structural properties and antioxidant capacity of gluten proteins of diverse bread and durum wheat varieties,and their relationship to the rheological performance of dough

The aim of this study was to compare five bread and five durum wheat genotypes for gliadins and glutenins profiles, the concentration of free sulphhydryl groups and disulphide bonds, antioxidant capacity of gluten proteins and their bread‐making performance. On average, bread wheat had significantly higher concentration of total sulphur‐rich (S‐rich) and sulphur‐poor (S‐poor) subunits of gliadins, as well as total low molecular weight (LMW) and high molecular weight (HMW) subunits of glutenins than durum wheat. However, durum wheat had higher concentration of S‐rich γ‐gliadins and S‐poor D‐LMW‐glutenins, but did not possess S‐poor ω‐gliadins. The concentration of disulphide bonds and total cysteine was higher in the durum gluten than that in the bread gluten, as well as antioxidant capacity (on average 90.6 vs. 85.9 mmol Trolox Eq kg^?1, respectively). In contrast to the bread wheat, the concentration of HMW‐glutenins was negatively associated with extensibility, as well as resistance to extension in durum wheat flour dough.     

From ancient to old and modern durum wheat varieties: interaction among cultivar traits,management, and technological quality

Following the boom in durum wheat breeding, ancient wheat disappeared from the human diet and old durum wheat varieties were replaced by what is believed to be their better versions: higher yielding modern varieties grown in high-input systems. Breeders have worked intensely ever since to improve the quality of durum wheat traits – mainly gluten subunit alleles – to obtain superior technological quality in the main durum wheat end products (first pasta and then bread) but conflicts about predicting their quality still exist. This is because quality is neither governed by one trait alone nor conditioned by a single controllable factor. This review discusses the evolution of wheat varieties from ancient to old, and then modern durum wheat in terms of agronomy, genetics, technological, and end-product qualities. Environmental effects will not be discussed. Moving from ancient to modern durum wheat varieties, grain yield increased, grain protein concentration decreased, and gluten strength and dough toughness improved, ameliorating the quality of pasta but decreasing the durum wheat versatility. © 2018 Society of Chemical Industry     

Spaghetti cooking quality of waxy and non‐waxy durum wheats and blends

Quality attributes of waxy durum wheat (Triticum turgidum L), milled semolina and cooked spaghetti were examined and compared with those of two non‐waxy durum cultivars. With the exception of kernel hardness, wheat quality characteristics were similar for both waxy and non‐waxy durum. Compared with average values obtained for durum wheat grown in North Dakota (USA) during the crop year 2000, the values obtained for the wheat used in this study were equal or better for most parameters evaluated. Semolina extraction for all samples was lower than the 2000 average of 62.6%. The waxy lines had higher ash, lower speck count, similar protein quantity, lower wet gluten and stronger mixograph curves than the non‐waxy cultivars. Waxy durum semolina had higher lipid content, starch damage, stirring number and flour swelling values. Spaghetti made from waxy durum semolina had shorter cooking time, similar cooking loss and cooked weight and lower firmness values, which would be unacceptable by most standards. Spaghetti made from blends containing 20–80% waxy durum semolina were evaluated. Cooking time and firmness decreased and cooking loss increased as the amount of waxy semolina increased. Acceptable spaghetti was obtained using 20–40% waxy semolina blends, depending on the quality of the non‐waxy blending material. Copyright © 2004 Society of Chemical Industry     

Effects of phosphorus and zinc fertilizer on cadmium uptake and distribution in flax and durum wheat

Cadmium accumulation in crops presents a potential risk to human health. To understand the difference between dicotyledonous and monocotyledonous species in respect of Cd accumulation, and to develop fertilizer management practices to minimise Cd uptake, a growth chamber study was conducted to evaluate the interactive effects of Cd concentration in phosphate and Zn fertilizer on Cd uptake in flax (Linum usitatissimum L) and durum wheat (Triticum turgidum L). Cadmium concentration was higher in flax than durum wheat shoots. Cadmium concentration was lower and Zn concentration higher in the flax seed and durum wheat grain than in the root, shoot or straw of both species. These results suggest that flax has comparatively ineffective barriers discriminating against the transport of Cd from the root to the shoot via the xylem, and that both crops may restrict Cd translocation to the seed/grain via the phloem. Commercial grade monoammonium phosphate (NH₄H₂PO₄) or triple superphosphate (Ca(H₂PO₄)₂) produced higher seed Cd concentrations than did reagent grade P in flax but not in durum wheat. Application of P significantly decreased seed/grain Zn concentration and increased seed/grain Cd concentration. Zinc addition at 20 mg Zn kg^?1 soil with P decreased seed/grain Cd concentration (average 42.2% for flax, 65.4% for durum wheat), Cd accumulation (average 37.2% for flax, 62.4% for durum wheat) and Cd translocation to the seed/grain (average 20.0% for flax, 34.5% for durum wheat) in both crops. These results indicate that there is an antagonistic effect of Zn on Cd for root uptake and distribution within the plant. Copyright © 2004 Society of Chemical Industry     

黑茶茶褐素与茶多糖对脂肪酶的抑制作用

为探讨黑茶茶褐素与茶多糖对脂肪酶的抑制作用,选择不同地区相同级别的黑茶为原料,提取茶褐素与茶多糖,采用对硝基苯酚法,分析茶褐素与茶多糖对脂肪酶活性的抑制率,并探讨各黑茶茶褐素与茶多糖对脂肪酶的抑制机理。结果表明:黑茶茶褐素与茶多糖对脂肪酶具有显著的抑制作用,普洱茶茶褐素与茶多糖IC50最小,分别为25.96,47.57mg/mL,抑制效果最好;其次为六堡茶;抑制效果最差的为茯砖茶褐素与茶多糖;康砖茶褐素与茶多糖抑制效果介于六堡茶与茯砖茶之间。各黑茶茶褐素的抑制类型均为可逆竞争性与非竞争性混合型,其中六堡茶接近于竞争性抑制类型;普洱茶、六堡茶与康砖茶多糖的抑制类型为可逆竞争性与非竞争性混合型,茯砖茶多糖抑制类型为可逆竞争性抑制。     

胡芦巴胶对混合粉制面包及生面团品质的影响

去皮高粱粉和粟米粉作面包用粉的替代物，以不同比例添加使用。胡芦巴胶部分替代面粉，替代率可达０．９％，研究了胡芦巴胶对流变特征及面包品质的影响。添加胶越多，生面团吸水量亦越高；添加胡芦巴胶后，生面团的稳定时间、断裂时间和机械耐力指数均有提高。按４∶１的面粉／高粱粉配方，添加０．６％胶可增大面包体积２１．８％，而０．９％的胶添加量能增大面包体积２１．３８％．     

Wheat starch granule protein: The isolation and characterisation of a salt-extractable protein from starch granules

A salt-extractable protein has been isolated and purified from large (A-type) wheat flour starch granules (Triticum aestivum cv. Maris Huntsman). This protein was the major species extractable with NaCl and because of its ease of extraction it was tentatively concluded that it was associated with the surface of the granules. It had a molecular weight of approximately 30 000 as determined by polyacrylamide gel electrophoresis in the presence of sodium dodecyl sulphate (SDS-PAGE) and an isoelectric point (pI) in excess of 10 as judged by analytical isoelectric focusing in polyacrylamide gel. The amino acid composition of the protein was quite different from those of wheat gluten proteins. A protein with similar properties was present on small (B-type) Maris Huntsman starch granules and it could also be detected on A-type granules from another variety of hexaploid breadwheat (T. aestivum cv. Flinor) as well as on A-type granules from tetraploid durum wheat (T. durum). This protein was not present on starch granules prepared from germinated grains (Maris Huntsman). The protein had neither α-amylase activity nor inhibitory activity against either wheat or hog pancreatic α-amylases. Several other proteins could be extracted from A-type starch granules but only after gelatinisation of the starch granule in the presence of SDS. The electrophoretic behaviour of these proteins was quite different from that of the NaCl-extracted protein and the rigorous conditions required to separate the latter proteins from the starch granules suggested that they are internal components of the granules.     

Inhibition of Propionibacterium acnes lipase by extracts of Indian medicinal plants

Lipases play an important role in pathogenesis of acne by hydrolysing sebum triglycerides and releasing irritating free fatty acids in the pilosebaceous follicles. Lipase is a strong chemotactic and proinflammatory antigen. Therefore, lipase has generated a high interest as a pharmacological target for antiacne drugs. The aim of this study was to identify inhibitory effects of plant extracts on the lipase activity of Propionibacterium acnes. Colorimetric microassay was used to determine lipase activity. Extracts from Terminalia chebula and Embelia ribes showed lower IC(50) value (1 μg mL(-1) ) for lipase inhibition as compared to Vitex negundo and Picrorhiza kurroa (19 and 47 μg mL(-1) , respectively). The active component responsible for lipase inhibition was isolated. This study reports for the first time the novel antilipase activity of chebulagic acid (IC(50) : 60 μmol L(-1) ) with minimum inhibitory concentration value of 12.5 μg mL(-1) against P. acnes. The inhibitory potential of plant extracts was further confirmed by plate assay. The organism was grown in the presence of subinhibitory concentrations of extracts from P. kurroa, V. negundo, T. chebula, E. ribes and antibiotics such as clindamycin and tetracycline. Extract from T. chebula showed significant inhibition of lipase activity and number of P. acnes.     

BREAD MAKING OF DURUM WHEAT WITH CHICKPEA SOURDOUGH OR COMPRESSED BAKER'S YEAST

Two ways of improving durum wheat bread-making quality were evaluated.
First, durum wheat (cultivar "Papadakis") was blended with bread wheat flour of good (A-flour) or medium (B-flour) quality (70% durum and 30% bread wheat flour). Durum wheat flour displayed the γ-gliadin 45 electrophoretic band and acceptable bread-making quality. Breads from flour blends had better volume, particularly the durum and A-flour blend. The addition of ascorbic and citric acid and malt flour improved dough rheological properties and thus bread volume, as well as staling rate and sensory characteristics. These were more pronounced in the blend of durum with B-flour.
Second, durum wheat flour alone was used to prepare chickpea sourdough-leavened bread, as flavor is important for consumer acceptance. With the addition only of salt, the chickpea sourdough-leavened durum wheat bread displayed acceptable loaf volume, distinguished flavor and longer shelf life compared with bread prepared with compressed baker's yeast.

PRACTICAL APPLICATIONS

One of the practical applications of this study is the possibility of using a common durum wheat cultivar instead of local varieties as is the case with traditional breads. Results of this work may be useful for promoting greater acceptance of durum wheat breads as well as expansion of the use of a traditional Mediterranean chickpea sourdough-leavened durum wheat bread with distinguished flavor and taste.
This work may serve as a guide for determining the quality of flours suitable for production of "home made" or "village" bread (which has high market value as specialty bread) by blending durum and bread wheat flours. Best results are obtained with good-quality bread wheat flour, regardless of the good quality of durum wheat cultivar used, together with the use of the dough improvers implemented in this work.