Influence of the addition of lupin sourdough with different lactobacilli on dough properties and bread quality

The aim of this research was to study the effects of solid‐state fermentation (SSF) with Lactobacillus sakei, Pediococcus pentosaceus and P. acidilactici on lupine sourdough parameters and lupine sourdough influence on the physical dough properties and wheat bread quality. The results showed that lactic acid bacteria (LAB) significantly reduced the pH and increased total titratable acidity (TTA) of SSF lupine. The highest protease activity in lupine is excreted by L. sakei (187.1 ± 8.6 PU g^?1), and the highest amylase activity, by P. pentosaceus (155.8 ± 7.5 AU g^?1). Lupine sourdough has a significant effect on the rheological properties of doughs, which affect the baking characteristics of the final product. In conclusion, it can be said that L. sakei, P. pentosaceus and P. acidilactici could be used for lupine SSF, and the addition of up to the 10% SSF lupine products increases the wheat–lupine bread quality.     

Impact of whey protein addition on wheat bread fermented with a spontaneous sourdough

Wheat bread is consumed in large quantities throughout the world. However, it contains an inadequate amount of proteins. This fact can be improved by adding whey protein concentrate (WPC). Sourdough (S) fermentation generally improves some characteristics and the digestibility of bread. The aim of this paper was to determinate the physicochemical properties and in vitro protein digestibility of bread with 20% of WPC leavened with spontaneous S (WPC 20-S). To complete the experimental design, bread with S without WPC (WPC 0-S) and bread with yeast (Y) without and with WPC 20% (WPC 0-Y and WPC 20-Y, respectively) were produced. WPC 20-S bread had higher pH, lower moisture and higher hardness and chewiness, compared with WPC 0-S. Interestingly, WPC had a negative effect only on the specific volume of bread fermented with Y but not when S was used. For all formulations, WPC improved the protein content and in vitro protein digestibility.     

小麦及其面粉品质对馒头品质的影响

综合分析了小麦与面粉的蛋白质品质、淀粉品质、酶、脂类物质等对馒头品质的影响。     

面粉中胚芽含量对面团流变学特性及馒头品质的影响研究

在小麦面粉中添加同种小麦提取的胚芽所制成的胚芽粉,测定其面团流变学特性及降落数值,并做馒头感官评价试验。实验表明,拉伸面积、最大拉伸阻力、拉伸阻力、拉伸比例、稳定时间和粉质质量指数与胚芽添加量呈显著线性负相关;弱化度与胚芽添加量呈显著的线性正相关;降落数值、形成时间与胚芽添加量线的相关性不显著。在一定添加范围内(0～2%)馒头总评分随胚芽粉添加量增大而增大,超过此数值则馒头总评分随添加量增加而减小;馒头的麦香味也有此趋势。     

Growth inhibition of Fusarium graminearum and deoxynivalenol detoxification by lactic acid bacteria and their application in sourdough bread

Eight lactic acid bacteria (LAB) strains were screened for their ability to inhibit Fusarium graminearum (F. graminearum) growth and remove deoxynivalenol (DON). Furthermore, the selected LAB strains were applied as starter cultures to evaluate their performance during the breadmaking process. Lactobacillus plantarum (L. plantarum) AR524 exhibited strong inhibitory activity against F. graminearum growth in a pH-dependent manner and removed up to 40.9% of DON, mainly through cell wall binding. Compared with the control, L. plantarum AR524 inhibited 60.19% of F. graminearum growth and removed 50.53% of DON during breadmaking. The texture properties of the bread were also remarkably improved by L. plantarum AR524, and its shelf life was extended from 3 days to 6 days without the application of any chemical preservatives. Therefore, L. plantarum AR524 shows excellent potential for application as a bioprotective starter culture in bakery products.     

Modulation of the nutritional value of lupine wholemeal and protein isolates using submerged and solid‐state fermentation with Pediococcus pentosaceus strains

The influence of different factors (submerged and/or solid‐state fermentation, pediococci strain, lupine variety and protein isolation process) on the protein digestibility, total phenolic compounds (TPC) content and radical scavenging activity of Lupinus luteus and angustifolius wholemeal and protein isolates was evaluated. As safety factor, biogenic amines (Bas) formation was analysed. The Pediococcus pentosaceus strains No. 8, No. 9 and No. 10 are suitable starters for lupine wholemeal fermentation and both applied processes (fermentation and protein isolation) increase protein digestibility (by 10%). Higher TPC content in fermented wholemeal can be obtained, compare to isolates. In SMF isolates by 58.3%, 68.2%, 95.6%, 76.6%, lower content of phenylethylamine, putrescine, cadaverine and histamine, respectively was found. The highest protein digestibility and the lowest BAs content using submerged fermentation with pediococcus No. 8 in lupine variety Vilnius protein isolates can be obtained and this technology for high‐quality lupine proteins preparation can be recommended.     

Hearth bread baking quality of durum wheat varying in protein composition and physical dough properties

Thirty durum wheat genotypes from ten countries of origin were grown in field plots for two consecutive years. Three of the genotypes were γ‐gliadin 42 types and the remainder were γ‐gliadin 45 types. Among the γ‐gliadin 45 types, six high‐molecular‐weight glutenin subunit (HMW‐GS) patterns were identified: 6 + 8, 7 + 8, 7 + 16, 14 + 15, 20 and 2*, 20. All the γ‐gliadin 42 genotypes contained low amounts of unextractable polymeric protein (UPP) and exhibited low gluten index values and weak gluten properties. The γ‐gliadin 45 genotypes exhibited a wide range of UPP, gluten index and dough strength. HMW‐GS 20 genotypes were generally weak, whereas HMW‐GS 6 + 8 and 7 + 8 genotypes were generally strong. When baked by a lean formulation, long‐fermentation straight‐dough hearth bread process, the durum wheat genotypes exhibited a wide range of baking quality. Loaf volume and bread attributes were strongly correlated with UPP and gluten index. Some of the genotypes exhibited bread attributes and loaf volume equal or slightly superior to those of a high‐quality bread wheat flour. However, even the strongest durum wheat genotypes exhibited inferior fermentation tolerance to the bread wheat flour, as seen by a requirement for lower baking absorption during dough handling and more fragile dough properties when entering the oven. Among the HMW‐GS groups, HMW‐GS 7 + 8 and 6 + 8 exhibited the best and HMW‐GS 20 the poorest baking quality. Farinograph, alveograph and small‐scale extensigraph properties demonstrated that a combination of dough elasticity and extensibility was needed for superior durum wheat baking performance. Copyright © 2007 Society of Chemical Industry     

麦胚乳酸菌发酵饮品的工艺优化及品质分析

以麦胚为原料,利用复合乳酸菌发酵研制麦胚乳酸菌发酵饮品。以离心沉淀率为评价指标,优化稳定剂含量;采用单因素试验及正交试验,优化麦胚乳酸菌发酵饮品工艺条件,并测定其理化指标。结果表明,最佳稳定剂为羟丙基二淀粉磷酸酯0.5%、琼脂0.2%;最佳发酵工艺条件为嗜热链球菌（Streptococcus thermophiles）、保加利亚乳杆菌（Lactobacillus bulgaricus）、乳双歧杆菌（Bifidobacterium lactis）、鼠李糖乳杆菌（Lactobacillus rhamnosus）、植物乳杆菌（Lactobacillus plantarum）、嗜酸乳杆菌（Lactobacillus acidophilus）、干酪乳杆菌（Lactobacillus casei）按照配比1∶1∶1∶1∶1∶1∶1制备发酵剂,接种量0.03%,发酵时间24 h,发酵温度 42 ℃。在此最佳条件下,麦胚乳酸菌发酵饮品为乳酪色,质地黏稠,口感细腻,总蛋白3.53 g/100 g,总膳食纤维2.12 g/100 g,维生素E 1.28 mg/100 g,亚油酸669 mg/100 g,α-亚麻酸75.8 mg/100 g,乳酸活菌数2.1×109 CFU/mL。     

Application of whey of Mozzarella di Bufala Campana fermented by lactic acid bacteria as a bread biopreservative agent

A total of nine isolated lactic acid bacteria (LAB) from tomato and sourdough with antifungal activity were employed to revaluate the whey of Mozzarella di Bufala through the fermentation process for 72 h at 37 °C. Then, the fermented whey (BWF) was characterised and used as biopreservative in bread formulation. L. plantarum TR7 and L. plantarum TR2 strains showed average lactic acid concentration in BWF of 13.8 g L⁻¹. Also, the bread volatile organic compounds (VOC) analysis showed an increase in hexanal, benzeneacetaldehyde, benzaldehyde and pyrazine tetramethyl when using BWF as ingredient. Moreover, the DPPH-inhibitory activity of bread with BWF extract also reflected a 33% rise in comparison with control bread. The application of BWF as a biopreservation agent in bread showed an increase in shelf life compared with bread with 0.3% calcium propionate and bread control for 2 and 15 days, respectively. BWF can be used as an interesting biopreservation strategy of bread.     

Optimisation of sourdough bread incorporation into wheat bread by response surface methodology: Bioactive and nutritional properties

The optimisation of the quantity of sourdough (A) prepared with two different fermentation methods, [spontaneous fermentation (F1) vs. starter of lactic acid bacteria‐added fermentation (F2)], instant active dry yeast (B) and wheat bran (C) for a nutritionally improved bread formulation has been studied by evaluating the bioavailability and bioactive properties. The bread produced according to the optimised formula and fermentation types of F1 (OB_F1) and F2 (OB_F2) was compared with control bread (CB). The optimised levels for F1 were 11.45% for sourdough, 1.10% for dry yeast and 1.58% for wheat bran and for F2 6.99% for sourdough, 1.02% for dry yeast and 38.84% for wheat bran. The addition of sourdough significantly (P < 0.05) affected antioxidant activity, total phenolic content, in vitro ash and protein digestibility, and enzyme resistance starch contents of bread. The F1 fermentation method was found to be more effective in terms of bread properties examined.     

麸皮预处理对全麦面团及面包的影响

本实验分别采用微波、烘烤、常压蒸汽、高压蒸汽对小麦麸皮进行预处理,研究比较了不同预处理方法对全麦面团和面包品质的影响。结果表明：和未处理全麦粉相比,烘烤、常压蒸汽和高压蒸汽处理均使全麦粉的稳定时间提高,其中常压蒸汽效果最显著,提高了4.2 min;同时,这三种处理方式分别使全麦面包的比容增加了6.92%、9.34%、5.19%,硬度分别降低11.81%、21.79%、19.57%,弹性分别提高2.59%、3.06%、1.65%。推测原因是这三种处理方式均显著降低了麸皮中的还原型谷胱甘肽含量,使全麦面团的游离巯基显著减少,二硫键显著增加,其中常压蒸汽和高压蒸汽效果最显著,分别使还原型谷胱甘肽减少了66.77%、69.30%,使游离巯基减少了40.43%、42.77%,使二硫键增加了51.35%、38.63%。综上,采用烘烤、常压蒸汽、高压蒸汽对麸皮预处理,可以通过降低还原型谷胱甘肽含量、提高二硫键含量来提高面团的稳定性,进而改善面包品质,且常压蒸汽处理的改善效果最好。     

馒头加工过程中发酵及蒸制对小麦淀粉结构特性的影响

以甘肃省白银市银春10号小麦粉为原料制作馒头。通过碱法提取面团发酵和馒头蒸制阶段的淀粉,对其结构特性进行研究。结果表明面团发酵不改变淀粉形态,馒头蒸制过程淀粉结构严重破坏,颗粒之间相互粘连形成片状结构。面团发酵过程中淀粉结晶度随面团发酵时间的增加先增加后降低,面团发酵20 min时达到最大(49.35%),馒头蒸制过程中淀粉结晶度显著低于小麦淀粉。面团发酵淀粉的1 047/1 022 cm^-1和1 022/995 cm^-1值高于小麦淀粉,而馒头蒸制淀粉的1 047/1 022 cm^-1值随着蒸制时间的延迟而降低至0.606,1 022/995 cm^-1则呈先增加后降低。面团发酵10 min和20 min时,淀粉粒径显著降低了3.0%和1.7%。面团发酵30 min淀粉T_o、T_p和T_c显著高于小麦淀粉,馒头蒸制时间从10 min延长至20 min过程中,淀粉ΔH显著升高了70.60%。     

Nutritional value of African yambean (Sphenostylis stenocarpa L): improvement by lactic acid fermentation

Tropical African yambean (Sphenostylis stenocarpa L) is an under‐utilised hardy, protein‐rich legume. Antinutrients and the excessively long cooking time (4–6 h), among other factors, limit the food use of African yambean seeds. To reduce these limitations, non‐traditional, less energy‐consuming processing methods are required. Seeds of different varieties were (i) examined for ingredients and (ii) fermented with Lactobacillus plantarum. Comparisons with traditionally cooked beans were made. Protein content and in vitro protein digestibility were increased slightly by fermentation or cooking. Reductions in trypsin and α‐amylase inhibitor activity and tannin ranged from significant to complete. The contents of potentially very toxic cyanogenic glycosides and flatulence‐causing α‐galactosides were high in raw beans. Reduction by fermentation (by 85%) was clearly more effective than by traditional cooking (10–20%). The results demonstrate (i) that fermentation can substantially improve the nutritional quality and (ii) that the energy requirement to produce a basic consumable fermented food from African yambean is only 10% of that of traditional cooking. On these grounds, widespread application of lactic acid fermentation by individuals or small‐scale industries would be advantageous in the context of small‐household economy, environmental protection, health and long‐term sustainable agriculture in Nigeria. Copyright © 2005 Society of Chemical Industry     

不同乳酸菌纯种发酵萝卜过程中品质的动态变化

以白萝卜为主要原料,利用植物乳杆菌、短乳杆菌、肠膜明串珠菌、戊糖片球菌进行纯种发酵,并以自然发酵萝卜为对照,对发酵过程中泡萝卜的总酸及氨基态氮、亚硝酸盐、脆度4个理化指标进行动态测定,同时利用顶空固相微萃取和气质联用方法对发酵成熟的泡萝卜的挥发性风味物质进行测定。结果表明,接种发酵可以明显的缩短发酵周期,提升产品品质。      

Wheat dough rheology and bread quality effected by Lactobacillus brevis preferment,dry sourdough and lactic acid addition

The influence of chemical and biological acidification on dough rheological properties and bread quality has been investigated. Two different flour types were used. Dough was chemically acidified with lactic acid. Two types of biologically acidified dough were prepared: dough with dry sourdough and with a Lactobacillus brevis preferment. Wheat dough rheological properties were investigated using the Farinograph, Extensograph and Amylograph. The baking response was also determined using standard baking tests. Addition of acidifiers resulted in firmer doughs with less stability, decreased extensibility and decreased gelatinisation maximum. The biological acidifiers increased the bread specific volume. Lactic acid addition had no influence on bread specific volume. In general, biological and chemical acidification decreased bread hardness. The addition of dry sourdough significantly decreased the lightness and increased the yellowness and redness of the bread crumb. The crust chroma, hue angle and brownness index were significantly changed by addition of acidifiers.     

Quality attributes and firming kinetics of partially baked frozen wholewheat bread with sourdough

Partially baked frozen (PBF) process prolongs bread shelf life, but diminishes its volume and crumb texture. Therefore, we investigated the possibility of using sourdough for the quality improvement in PBF wholewheat bread. Sourdough was fermented with either Lactobacillus plantarum, Lb. brevis or Leuconostoc mesenteroides mixed with yeast Candida humilis and added at 7.5, 15, 22.5 or 30% on bread dough basis. The choice of sourdough starter significantly affected bread acidity characteristics, flavour, specific volume, shape and crumb firmness. The sourdough amount and acetic acid content of bread inversely correlated to flavour score, specific volume, shape and crumb softness. The overall quality of PBF wholewheat bread was most efficiently improved after adding Lb. plantarum sourdough at 15–22.5%, resulting in retarded firming rate (74–94%) and improved specific volume (25–28%) in comparison with PBF bread without sourdough. Such sourdough has lactic to acetic acid higher than previously recommended for traditional sourbreads.     

新麦26不同粉路小麦粉及其面包品质的分析

在小麦制粉过程中,因出粉部位的不同而导致了各粉路粉品质存在差异。以金像面包粉为对照,选用新麦26品种小麦为原料,利用实验磨制粉得到3路皮粉和3路心粉,通过测定其主要成分、粉质参数、RVA糊化特性及其面包TPA参数,确定用于面包制作的粉路粉。结果表明皮粉蛋白质和湿面筋含量均高于心粉,前路皮粉低于后路皮粉,前路心粉高于后路心粉;各粉路粉的面团形成时间、稳定时间和峰值粘度、回生值以及面包的弹性和回复性都与其蛋白质含量变化规律一致;1M粉的灰分含量最小,3M粉的吸水率和脂肪含量最大,3B粉的面包硬度、咀嚼性、弱化度和稀懈值最小。通过与金像对照组比较分析可知,新麦26的后路皮粉和前路心粉均可用于面包粉的生产,皮粉中以3B粉最佳,心粉中以1M粉最佳。