Designing a Score-Based Method for the Evaluation of the Nutritional Quality of the Gluten-Free Bakery Products and their Gluten-Containing Counterparts

Gluten-free (GF) products are consumed both by individuals with celiac disease and by an increasing number of people with no specific medical needs. Although the technological quality of GF products has been recently improved, their nutritional quality is still scarcely addressed. Moreover, the few published studies report conflicting results, mostly because the information from product nutrition facts is the only considered factor. The aim of the present study was to develop a score-based method for the nutritional evaluation of 134 packaged Italian GF bakery products and to compare it with that of 162 matched gluten-containing (GC) food items. The score included the information from the nutrition facts and the presence/absence of some nutritionally relevant components in the ingredients list. Results indicated an overall low nutritional quality of the considered GF bakery products. Additionally, with the sole exception of GF bread substitutes, there was no difference in nutritional quality between GF and equivalent GC bakery products. Future research and development of GF bakery products may take advantage of this scoring method, as it may represent an easy approach to evaluate their nutritional quality. The present findings do not justify the consumption of packaged GF bakery products by people without any specific medical needs.     

Effect of arabinoxylans and laccase on batter rheology and quality of yeast-leavened gluten-free breads

The supplementation effects of maize fiber arabinoxylans (MFAX, 0%–6%), laccase (0–2 U/g flour) and water absorption level (90%–100%) on gluten-free (GF) batter rheology and bread quality were analyzed. From viscoamylograph analysis, lower starch amount in GF flour due to MFAX addition decreased peak viscosity and retrogradation. Surface response plots showed that laccase did not have significant effect on GF batter rheology and bread quality, whilst water was the most important variable. Higher levels of water absorption benefited bread texture. Higher water level (>100 mL/100 g flour) was needed in the experimental design to evaluate correctly the effect of 6% MFAX replacement on GF bread quality. Further analyses were carried in order to adjust water absorption of batters according to their consistency index (K ≈ 100 Pa sⁿ), resulting an optimal water absorptions of 95%, 100% and 105% for control flour and flours supplemented with 3% or 6% MFAX, respectively. Thus, MFAX addition enhanced water-binding capacity of flour and yielded GF breads with higher specific volume and softer crumb texture. These quality parameters were best rated with 6% MFAX addition to flours. This research demonstrated the potential of MFAX to develop GF breads with improved quality, when optimal water level is used.     

Nutritional Differences Between a Gluten-free Diet and a Diet Containing Equivalent Products with Gluten

The gluten-free (GF) products market represents one of the most prosperous markets in the field of food and beverages in the immediate future. Historically, counselling for celiac disease has focused on the absence of gluten in foods, however the nutritional quality of GF foodstuffs is an important aspect to consider. The aim of the present work was to compare the nutritional composition of the 206 GF rendered products most consumed in Spain, against the composition of 289 equivalent foods with gluten, and to make a comparison between the diet including GF products and the same diet with equivalent products with gluten in a 58 adult celiac population. The results of the present collaborative study pointed out differences in calorie, macronutrient, fiber, sodium, salt and cholesterol content between GF rendered and gluten-containing foodstuffs. Thus, calorie and nutrient intake in a GF diet is different when compared to its equivalent diet with gluten. Following a diet based on GF products could suppose a nutritional imbalance for celiac patients as well as for non-celiacs who follow a diet that includes many GF rendered foodstuffs.     

Characterisation of gluten-free pasta through conventional and innovative methods: Evaluation of the cooking behaviour

The rapid stiffening of a well-developed gluten network able to entrap swollen starch granules is a key factor for the high quality of durum wheat pasta during cooking. Good resistance and firmness, low stickiness and limited release of organic materials into the cooking water are quality traits of primary importance for traditional pasta. In gluten-free (GF) pasta, the formation of a scaffold of retrograded starch can be an alternative to gluten networking: it confers rigidity to the cooked product and reduces pasta stickiness and loss of soluble materials into the cooking water. In a previous paper, 14 commercial GF spaghetti samples were studied as uncooked products from a chemical, biochemical and physical point of view. The aim of this study was to determine the cooking behaviour of these samples. A durum wheat pasta was also included as reference. Suitable cooking conditions were adopted and different conventional and innovative evaluations (i.e. compression test, creep test) were performed as a function of cooking time. Different behaviours were evidenced, often related to the ultrastructural organization of the uncooked products. In particular, the creep test revealed to be very effective in discriminating among the properties of the different GF spaghetti.     

Characterisation of gluten-free pasta through conventional and innovative methods: Evaluation of the cooking behaviour

The rapid stiffening of a well-developed gluten network able to entrap swollen starch granules is a key factor for the high quality of durum wheat pasta during cooking. Good resistance and firmness, low stickiness and limited release of organic materials into the cooking water are quality traits of primary importance for traditional pasta. In gluten-free (GF) pasta, the formation of a scaffold of retrograded starch can be an alternative to gluten networking: it confers rigidity to the cooked product and reduces pasta stickiness and loss of soluble materials into the cooking water. In a previous paper, 14 commercial GF spaghetti samples were studied as uncooked products from a chemical, biochemical and physical point of view. The aim of this study was to determine the cooking behaviour of these samples. A durum wheat pasta was also included as reference. Suitable cooking conditions were adopted and different conventional and innovative evaluations (i.e. compression test, creep test) were performed as a function of cooking time. Different behaviours were evidenced, often related to the ultrastructural organization of the uncooked products. In particular, the creep test revealed to be very effective in discriminating among the properties of the different GF spaghetti.     

茶多酚对肠道微生物的调节作用研究进展

代谢综合征是高血压、血糖异常、血脂紊乱和肥胖症等疾病在人体内集结的一组复杂的代谢紊乱症候群。茶多酚是茶叶中的特征次生代谢产物之一,最新研究表明,茶多酚可以通过对肠道菌群的干预,改善肠道菌群紊乱,调节宿主-肠道菌群的共代谢过程,进而达到改善代谢综合征的目的。本文系统总结了茶多酚的吸收与代谢,以及茶多酚在体外发酵模型、动物试验和临床试验中对肠道菌群的影响,阐述了茶多酚-微生物群-宿主三者之间的内在作用机制,有助于以肠道菌群理论为基础探讨茶多酚对人体健康的作用,并为茶多酚的功能性产品开发提供理论依据。     

Role of enzymes in improving the functionality of proteins in non-wheat dough systems

Gluten free systems lack the viscoelastic network required to resist gas production and expansion during baking. Enzymatic treatments of the GF flours have been proposed initially for creating protein aggregates that mimic gluten functionality but then also for modifying proteins changing their functionality in GF systems. To better exploit the technological function and the potentials of enzymatic processing for improving GF bread quality, it is important to understand the key elements that define the microstructure and baking functionality of GF batters as compared to wheat dough. In this review, some keys are pointed out to explain the different mechanisms that are available for understanding the action of enzymes to effectively design GF viscoelastic matrixes. Focus will be on protein modifying enzymes, because they play a decisive role in the formation of the fine network responsible for improving the expansion of rice batters.     

The comparison of the effect of added amaranth,buckwheat, chickpea,corn, millet and quinoa flour on rice dough rheological characteristics,textural and sensory quality of bread

Gluten free (GF) flour (amaranth, buckwheat, chickpea, corn, millet and quinoa) was blended with rice flour to compare their impact on dough rheological characteristics and bread quality. The potential of some GF-rice blends in breadmaking has already been studied on blends with prevailing content of rice flour. The impact of added flour may be expected to rise with increasing amount of flour; therefore blends containing 30 g/100 g, 50 g/100 g and 70 g/100 g of GF flour in 100 g of GF-rice blend were tested. Under uniaxial deformation, peak strain was not impacted by the addition of GF flour; stress (12.3 kPa) was, however, significantly (P < 0.05) decreased (2.9–6.2 kPa). The reduction initiated by the presence of buckwheat, chickpea, quinoa and partly amaranth, together with thermally-induced dough weakening initiated by buckwheat and quinoa flour, may be related to significantly better crumb porosity. Overall acceptability of composite breads containing amaranth, chickpea and quinoa was negatively impacted by the aroma and taste of these flours. Higher potential to improve rice dough behavior and bread quality was found in the blend containing buckwheat flour (30 g/100 g; 50 g/100 g). Millet and corn flour deteriorated dough and bread quality.     

Quality improvement of rice-based gluten-free bread using different dietary fibre fractions of rice bran

Gluten-free (GF) breads are often characterised by low nutritional quality as they are mainly starch based and contain low amounts of vitamins, minerals and in particular dietary fibre. The objective of this study was to improve the physical, nutritional and sensory quality and shelf life of rice-based GF bread by adding different fractions of rice bran, containing different amounts of protein, fat, dietary fibre (DF) and different ratios of insoluble (IDF) to soluble (SDF) DF.     

Quality Indicators and Heat Damage of Dried and Cooked Gluten Free Spaghetti

Plant Foods for Human Nutrition - The quality and safety indicators of commercial dried gluten free (GF) pasta were analyzed to investigate, for the first time, the real nutritional intake through...     

Low Light During Grain Filling Stage Deteriorates Rice Cooking Quality,but not Nutritional Value

To investigate the effect of low light (LL, 50% natural light) during grain filling (GF) stage on rice transamination, amino acid (AA) accumulation, nutritional value, and cooking quality in three different rice genotypes, transaminase activities and AA levels in grains during GF stage and the traits that significantly affected rice quality (physical appearance, cooking quality, and nutritional value) were analyzed. LL did not disturb transamination in rice grains during GF stage, as minimal impact was found on alanine and aspartate transaminase activities. Nevertheless, most AAs in caryopses, including lysine and threonine, increased in response to LL, except for sulfur-containing AAs. These results suggest that AA metabolism and accumulation in rice grains were rarely suppressed by LL during GF stage. Rice nutritional ingredients at harvest, such as major protein components including glutelin and most important essential amino acids (EAAs) including lysine and threonine, increased significantly in response to LL, whereas most protein and EAA ratios were rarely affected. However, LL markedly affected physical appearance of rice grains by reducing brown rice rate, milled rice rate, and 1000-grain weight and increasing the chalkiness rate. In addition, cooking qualities decreased in response to LL, while breakdown values and amylose levels decreased and setback values increased. We concluded that LL during GF stage decreased the cooking quality of rice, but could potentially improve the nutritional value of rice.     

Folate Content and Chemical Composition of Commercially Available Gluten-Free Flour Alternatives

Plant Foods for Human Nutrition - Concerns about the nutritional and sensory qualities of gluten-free (GF) products has generated interest in the evaluation of novel gluten-free ingredients. Folate...     

种茎直接补种对甘蔗宿根性的影响——以2017年广西融水苗族自治县试验为例

研究以品种‘桂辐98-296’(‘GF98-296’)种茎直接补种‘桂柳05-136’(‘GL05-136’)宿根蔗地对甘蔗农艺性状及其经济效益的影响,以解决甘蔗宿根缺株断垄问题,为推广“种茎直接补种新技术”提供科学依据。试验设‘GF98-296’种茎直接补种‘GL05-136’宿根蔗地（处理A）、‘GL05-136’种茎直接补种‘GL05-136’宿根蔗地（处理B）、不补种自然状态下‘GL05-136’宿根蔗地（CK）,共3个处理;在‘GL05-136’宿根苗期2~4张叶片时期实施补种,到工艺成熟期调查3个处理甘蔗的农艺性状及其单位面积产量,并进行比较分析。结果表明：处理A产量为79.55 t/hm²,分别比CK、处理B增产19.29、13.91 t/hm²,增幅分别达32.01%、21.18%,且差异达极显著水平;处理B产量与CK差异不显著;直接补种不影响‘GL05-136’宿根蔗的发株、产量和蔗糖分;工艺成熟期时,‘GF98-296’蔗茎的蔗糖分与‘GL05-136’宿根蔗茎的相当。经济效益分析表明,以‘GF98-296’种茎直接补种‘GL05-136’宿根蔗地,蔗农增收5071.0元/hm²;制糖企业可增加工业产值15 573.0元/hm²。表明‘GF98-296’适宜作为‘GL05-136’宿根蔗地种茎直接补种品种,可进行大面积示范和推广。     

Innovative approaches towards improved gluten-free bread properties

Up to now, most of the research available to improve gluten-free (GF) bread is based on substituting or imitating the gluten network. Slightly less attention is given to technological approaches that modify batter properties such as consistency. This review summarizes the most recent advances to improve GF bread quality, focusing on latest conventional ingredients (e.g. hydrocolloids) and new innovative approaches to replace the gluten-network (i.e., use of enzymes, alternative polymer network), but especially on novel technological approaches, such as high hydrostatic pressure, sourdough technology and non-conventional heating methods. In general, hydrocolloids are still the most studied and well-known additives to gluten-free products, followed by the use of crosslinking enzymes. Within the review, special focus is given to the application of arabinoxylans, which form a stable carbohydrate network in GF batters that may substitute gluten. However, it was seen that technological approaches provide better solutions for enhancing GF bread properties than the latter, especially when non-conventional baking alternatives are applied. From these, ohmic heating resulted the most promising approach to overcome bread quality issues, while remaining time and energy-efficient.     

氟对黑茶中的冠突散囊菌和黑曲霉生长的影响

用单孢子接种,分别通过固体平板培养与液体培养,测定氟对分离自黑茶的6株冠突散囊菌和1株黑曲霉生长的抑制率、菌体生长速率和菌丝生物量,研究氟对各菌株生长的影响。结果表明：6株冠突散囊菌在含氟2 000 mg/L、黑曲霉在含氟1 800 mg/L的固体培养基中能生长。100 mg/L剂量的氟对冠突散囊菌生长的抑制率为0.76%~10.24%,对黑曲霉的抑制率达35.71%。随氟浓度的增加,生长速率变小,抑制率增大。液体培养中,100 mg/L的氟对冠突散囊菌与黑曲霉菌丝生物量的抑制率分别为34.47%、80.59%。冠突散囊菌的子囊孢子与黑曲霉的分生孢子对氟具有较强的耐受性,且两种培养方式表明冠突散囊菌比黑曲霉更耐氟。     

Investigations on mechanical characteristics of glass fiber reinforced epoxy composite modified with amino-terminated hyperbranched polymer

Glass fiber, GF, which was first hydroxylated and silanized, was incorporated into epoxy resin modified with amino-terminated hyperbranched polymer (ATHBP) to obtain high performance composite. The effects of GFs content on the mechanical properties of composites were investigated, discussing the results from flexural, tensile, and impact tests. The composites revealed noticeable improvement in flexural strength, tensile strength as well as impact strength but slow decrease in elongation at break, compared to the epoxy/ATHBP thermoset. FESEM morphology results indicated the good compatibility between epoxy matrix and GF in the appearance of ATHBP and showed that the toughening mechanism was mainly attributed to the stress transfer mechanism.     

A Comparative Study of the Thermoplastic Polyurethane/Carbon Nanotube and Natural Rubber/Carbon Nanotube Composites According to Their Mechanical and Electrical Properties

The present study investigated Thermoplastic Polyurethane (TPU), Natural rubber (NR) and their composites in terms of their mechanical and electrical properties for developing wearable stretch sensors. Both TPU and NR were added 2 %wt Multi-wall Carbon Nanotube (MWCNT), then in order to test their influences on TPU/CNT and NR/CNT composites. The result showed that Young’s modulus and Yield point of this experiment were higher than bare TPU and NR, whereas their stress-strain hysteresis loops were bigger than bare TPU and NR. Moreover, the Gauge factor (GF) value of TPU/CNT was much higher than NR/CNT composites at 100 % strain with 7.08. TPU/CNT composites promise to have many applications in the field of stretch sensors with good stability and durability while NR and NR/CNT were easy deformed when the stretch was applied.     

国家第六轮甘蔗品种区试云南瑞丽点DTOPSIS法综合评价

利用DTOPSIS对参加国家甘蔗品种第六轮区试的13个品种,在云南瑞丽点两年新植1年宿根的品比结果,进行了综合分析,结果:闽糖95-261、福农99-20169、粤甘18号、福农02-3924、闽糖96-6016、桂引6号、粤甘16号、桂辐98-296、云蔗99-91九个品种的综合表现优于双对照ROC16(CK1)和粤糖93-159(CK2),适宜在湿热生态型蔗区推广应用;Rb76-5418的综合表现优于ROC16(CK1)。评价结果与糖产量排序基本一致,与甘蔗品种在云南瑞丽蔗区的实际表现吻合。     

Structural role of fibre addition to increase knowledge of non-gluten bread

Dietary fibres can play a significant role in GF bread development. Besides their well documented health benefits, dietary fibres can improve the texture, sensory characteristics and shelf life of baked products, due to their water binding capacity, gel forming ability, fat mimetic, textural and thickening effects. Dietary fibres from different sources are discussed in this paper and their role in GF products' making is analysed. The sources of fibres vary: flours, fruit and vegetable processing by-products, isolated ingredients, seeds or mixtures of all of these can be used. Fibres improve the structure and result in dense crumb porosity. Tasty products with soft crumb can be produced, and there are many perspectives in further products development.     

国家甘蔗品种第六轮区域试验在广西南宁点和隆安点的表现

2009年广西甘蔗研究所试验农场和隆安县金穗公司农场对11个参试材料和2个对照品种进行了1年新植的区域试验和1年新植的生产试验。结果表明:桂辐98/296平均蔗茎产量和含糖量最高,增产增糖明显。闽糖95/261、赣南99/591和B8的平均蔗茎产量和平均含糖量均高于两对照,表现较好,其它品种表现不突出。福农02/3924、粤甘18和福农99/20169早熟高糖,平均甘蔗蔗糖分高于两对照,其它品种的甘蔗蔗糖分表现不突出。