Gluten contamination in oat products and products naturally free from gluten

Some countries now allow celiac patients to include oats in their gluten-free diet. Studies have shown that commercially available oats can be contaminated with gluten. The aim of the study was to analyse oat products and products naturally free from gluten to determine the degree of contamination. A total of 88 oat products and 22 products based on maize, rice, millet or buckwheat were analysed, using a commercially available enzyme-linked immunosorbent assay (ELISA) with a monoclonal antibody to gliadin. The ELISA is quantitative with a detection limit of 20 mg/kg gluten. Some of the positive samples were also analysed for the presence of DNA from wheat, barley or rye. Thirteen percent of the oat products had gluten content over 200 mg/kg. Of the products naturally free from gluten 14% had a gluten content over 200 mg/kg. There was a tendency for higher levels of contamination with increased processing. The risk of gluten contamination in oat products as well as in non-gluten cereals must be considered. The level of contamination was in most cases low. The results regarding oats can be compared to those of such cereals as maize, rice, buckwheat and millet.     

原料类型对膨化米糊特性的影响研究

以籼稻、粳稻和糯稻三种不同类型稻米为原料制备膨化米糊,研究其理化特性和感官特性,分析原料类型对其理化特性和感官特性的影响。结果表明：稻米原料类型对膨化米糊的沉淀率C、溶解率R、沉淀吸水率5等均有极显著影响;原料类型对米糊的色泽和香气有显著影响,对口感、滋味和总分影响不大。     

茯苓复配谷物挤压重组米的物性变化

以茯苓分别与薏米、红米、大米、苦荞四种谷物进行复配,采用双螺杆挤压技术制备成重组米,研究其物性变化。结果表明,相比薏米、红米、大米、苦荞四种谷物原料,复配茯苓的重组米糊化度分别增大了230. 8%、202. 1%、206. 8%、215. 7%,复水时间分别缩短了1. 04倍、0. 76倍、0. 83倍、0. 82倍,复水率分别增大了15. 88%、19. 45%、17. 97%、19. 94%,四种谷物消化性和复水性得以改善。相比四种全谷物重组米,复配茯苓的重组米色泽较好,但硬度增大,咀嚼性、弹性、黏附性及内聚性有所下降;水分以结合水和不易流动水的形式存在,自由水为0;淀粉回生度增大,V型晶体的衍射峰强度增强。     

Consumers’ attitudes towards alternative grains: a conjoint analysis study

Recently, alternative grains (millet, quinoa, sorghum) have been used to produce several food products common to North Americans. The objective of this study was to identify the attributes that drive consumers liking of alternative grains. A literature review and two focus groups were conducted. Four attributes were identified as being important to consumers when purchasing alternative grains. These attributes included grains, product type, flavour and claims. A choice- based conjoint analysis survey was created and administered to 346 individuals who live in Atlantic Canada. Product type and flavour were the most important attributes to consumers. Sweet and nutty flavours, products made from quinoa, or products with claims indicating they were a source of fibre, reduced risk of type 2 diabetes or reduced risk of cardiovascular disease, had a positive effect on consumer liking.     

石花菜多糖对无麸质食品品质特性的影响

由于不含麸质蛋白,无麸质食品常存在产品品质不佳的主要缺陷。石花菜多糖（Gelidium amansii polysaccharides,GAP）因其良好的亲水性能和凝胶特性,具有作为稳定剂和增稠剂改善无麸质食品的潜力。该文探究添加不同水平GAP对无麸质面条和无麸质面包品质特性的影响,结果表明,添加GAP后的无麸质面团挤压出的面条表面平整和光滑,延展性和拉伸性好,且微观结构出现连续“胶状”淀粉结构。添加GAP后,无麸质面条的硬度降低,最佳烹饪时间缩短,烹饪损失降低,吸水率升高。同时,添加GAP明显降低无麸质面包的硬度和咀嚼性,提高面包的水分含量并降低其烘焙损失。其中以6%的GAP替代玉米淀粉[即玉米淀粉/马铃薯淀粉/GAP（质量分数）为74%/20%/6%]在改善产品品质方面的潜力最大。GAP具有作为亲水胶体改善无麸质产品品质的优良特性,或可为高品质无麸质食品的开发提供新思路。     

无麸质食品现状及品质改良研究进展

综述了无麸质食品的现状、缺陷及产品改良的研究进展,以期为无麸质食品的发展提供参考。     

无麸质饮食的研究进展

麸质蛋白是主要存在于小麦、黑麦和大麦等中的贮藏蛋白,可引起麸质蛋白相关性疾病,包括自身免疫性疾病、过敏性疾病和非乳糜泻麸质敏感性疾病。无麸质饮食是目前针对这些患病人群唯一有效的饮食治疗方式,此饮食需避免或严格限制含麸质食品的摄入。随着无麸质饮食在临床中的广泛应用,其在麸质敏感性群体甚至健康人群中开始流行,但长期的无麸质饮食会带来一定的营养缺乏、重金属积累以及代谢异常等健康问题,因而如何通过改善饮食方式来弥补无麸质食品营养缺陷并开发出更加安全健康的无麸质食品正成为新的研究趋势。本文综述了无麸质饮食的现状,无麸质饮食与疾病,无麸质饮食的健康挑战,以及无麸质食品的缺陷与品质改良,为无麸质饮食进一步研究和无麸质食品开发提供理论依据和参考。     

Study of selected quality and agronomic characteristics and their interrelationship in Kabuli‐type chickpea genotypes (Cicer arietinum L.)

Impact of genotype on quality, agronomic characteristics and their interrelationship in Kabuli‐type chickpea was investigated to provide significant feedback to breeder for selection/evolution of the most suitable varieties. Seven genotypes were studied for seventeen physical, chemical and agronomic characteristics. The effect of Kabuli‐type chickpea genotype on the physicochemical parameters, cooking time and agronomic characteristics were significant. Maximum seed size and volume were recorded for CC98/99 (0.32 g and 0.26 mL seed^?1, respectively), density and swelling index for the genotype FLIP97‐179C (having minimum seed size and volume), while the rest of the genotypes were statistically the same. Weight, volume after hydration, hydration capacity and swelling capacity followed the same pattern. Maximum moisture, protein and mineral concentration were noted in CC98/99. Seed protein concentration for the remaining genotypes was statistically non‐significant from one another. Longer period was taken by CM 2000 for flowering and maturity (130 and 181 days, respectively). Minimum time to flowering and maturity was taken by CC98/99. Genotype CC 98/99 outyielded all other genotypes (2107 kg ha^?1). Seed size and seed volume were strongly and positively correlated with protein content, weight after hydration, volume after hydration, hydration and swelling capacities (r = 0.83–1.0). Strong correlation was also noted among different agronomic characters.     

Physical properties,chemical characterization and fatty acid composition of Mexican chia (Salvia hispanica L.) seeds

Chia seeds were utilized by Aztecs as food and for medicinal purposes. Nowadays, this crop is gaining importance in many countries, due to its nutritional attributes. Some physical properties and chemical characteristics of chia seeds from four different regions of Mexico were evaluated and compared. Seed size distribution was not significantly affected (P > 0.05) by the region, with similar values of seed length (2.03–2.10 mm), width (1.27–1.32 mm), thickness (0.77–0.81 mm) and surface area (4.95–5.42 mm²). Bulk density (662–741 kg m^?3), geometry and granulometric distribution were also determined. Origin of tested seeds significantly (P < 0.05) influenced their composition; all seeds had high contents of protein (18.5–22.3%), fat (21.5–32.7%) and fibre (20.1–36.1%). Chia seeds ratio between omega‐3 and omega‐6 fatty acids was 3:1 for the studied regions; seeds from Chiapas and Michoacán had the highest proportion of ω‐6 and ω‐3 fatty acids. The studied seeds contained phenolic compounds in the range of 0.53–0.71 mg GAE g^?1.     

必需氨基酸平衡的高水分拉丝蛋白制备及物理特性变化

为提升高水分拉丝蛋白的营养价值,研究以世界卫生组织（WHO）推荐的人体氨基酸模式为参比,通过求差平方和的数学计算方式构建了一种必需氨基酸评价模型来优化复合植物蛋白原料的配比,并研究了常用食品添加剂对复合植物蛋白制备的高水分拉丝蛋白物理特性的影响。实验结果表明,经必需氨基酸评价模型优化的高水分拉丝蛋白配方中各原料的质量分数为大豆蛋白50%、小麦蛋白25%、豌豆蛋白10%、花生蛋白10%、大米蛋白5%,制备的高水分拉丝蛋白质构特性为：硬度8.18 kg,弹性2.06 g•s,咀嚼性8.87 kg•s。优化配方下制备的高水分拉丝蛋白必需氨基酸比例较市售的植物性肉类替代品更接近人体氨基酸模式,具有更高的营养价值,并且与鸡肉和猪肉的质构特性相近。该研究对提升高水分拉丝蛋白的营养价值和改善复合植物蛋白制备高水分拉丝蛋白的物理特性提供了新思路,有助于开发营养美味的植物性肉类替代品。     

菊粉型果聚糖在无麸质产品中应用的研究进展

由于谷蛋白相关疾病与含谷蛋白食物的摄入有关,无麸质产品在食品工业中受到广泛关注,菊粉型果聚糖已成为无麸质产品的有益成分.本文介绍了菊粉型果聚糖在无麸质产品中应用的技术背景,阐述了菊粉型果聚糖的物理化学特性及其作为组成部分对无麸质产品的技术性能和感官质量的影响,分析了菊粉型果聚糖添加到无麸质产品后与其他成分和添加剂之间的...     

气流干燥机在高水分膨化饲料中的应用

介绍一种气流干燥机在膨化饲料上的干燥和冷却。该干燥机利用热空气穿透滞留在传送带上的饲料,直接传热和传质,降水能力在８％－１０％,干燥温度低,蛋白变性小,干燥后胚色浅,粉末度小,料胚表面无吸附水膜现象。     

Optimization of Gluten-Free Formulations for French-Style Breads

ABSTRACT:  The formulation of gluten-free bread, which will be suitable for patients with coeliac disease, was optimized to provide bread similar to French bread. The effects of the presence of hydrocolloids and the substitution of the flour basis by flour or proteins from different sources were studied. The added ingredients were (1) hydrocolloids (carboxymethylcellulose [CMC], guar gum, hydroxypropylmethylcellulose [HPMC], and xanthan gum), and (2) substitutes (buckwheat flour, whole egg powder, and whey proteins). The bread quality parameters measured were specific volume, dry matter of bread, crust color, crumb hardness, and gas cell size distribution. Specific volume was increased by guar gum and HPMC. Breads with guar gum had color characteristics similar to French bread. Hardness decreased with the addition of hydrocolloids, especially HPMC and guar. Breads with guar gum had the most heterogeneous cell size distribution, and guar gum was therefore selected for further formulations. Bread prepared with buckwheat flour had improved quality: an increased specific volume, a softer texture, color characteristics, and gas-cell size distribution similar to French bread. Bread with 1.9% guar gum (w/w, total flour basis) and 5% buckwheat flour (of all flours and substitutes) mimicked French bread quality attributes.     

富含挤压稳定化米糠粉面包的研制

研究了以挤压稳定化米糠粉为原料,生产面包的最适配方及技术条件。实验结果表明,添加10%的米糠粉可制得品质优良的面包。     

无麸质大米面包研究进展

开发大米面包不但可以丰富中国大米类产品的花色品种,还能解决麸质过敏人群对饮食多样化的需求。由于无麸质大米面包中不含面筋蛋白,在制作过程中存在面团难以形成有效的网络结构、不易成型、品质差(持水性、持气性、弹性和内聚性)、老化速率快等缺点。近年来,研究人员通过改进工艺条件、添加品质改良剂等方法,对无麸质大米面包品质进行改善,文章简述了无麸质食品的相关标准和大米面包使用的原料,并介绍了其工艺和品质改良研究进展,以期为无麸质大米面包的产业化开发提供参考。