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1.
Whole wheat bread represents an important source of dietary fibre and micronutrients such as minerals and vitamins (B1, B2, B6). Thus it is important to control losses of vitamins during milling and breadmaking. The classical (yeast) breadmaking process is a relatively severe, leading to a 48% loss of thiamine in white bread. Longer fermentation times (white bread) led to higher thiamine concentrations (2.5 μg/g) than shorter fermentations (1.4 μg/g). In whole wheat bread, separate yeast or sourdough fermentations maintained vitamin B1 levels close to that of the original flour (5.5 μg/g). Whole wheat breadmaking with yeast (from kneading to final bread), in long fermentations, resulted in a 30% enrichment in riboflavin. The pyridoxine concentration of whole wheat flour is 5-fold higher than white flour, but classical fermentations resulted in a severe depletion in pyridoxine (−47%). The use of mixed fermentation conditions (yeast plus sourdough) had no synergistic impact on B vitamin levels. The classical breadmaking protocol is time-saving but does not result in maximal vitamin retention. Highest levels of B vitamins were achieved by long yeast fermentations.  相似文献   

2.
The aim was to evaluate the effect of sourdough and dietary fiber addition, as well as partially baked frozen (PBF) technology, on biological value of proteins, lipid profile, and some minerals content in selected tissues of rats.In all breads, the limited amino acid was lysine. Proteins of PBF conventional and PBF breads with an addition of dietary fiber (PBF DF breads) had significantly higher Chemical score and Essential amino acid index in comparison to proteins of Direct bread (P < 0.05). Protein digestibility corrected amino acids score was significantly lower in Direct DF and PBF improved breads (P < 0.05).Addition of fiber to Direct and PBF bread decreased significantly total digestibility of protein compared to all groups (P < 0.05).Concentration of calcium was significantly lower in liver of rats fed with Direct sourdough and PBF improved breads in comparison to rodents fed with Direct bread. The concentration of iron was significantly higher in liver of animals fed with Direct bread. The highest level of calcium in femoral bones of rats was shown in groups fed with PBF conventional bread. The lowest level of iron was measured in femoral bone of rats fed with PBF sourdough bread in comparison to the rest of the experimental groups.  相似文献   

3.
The possibility of using naked barley for food products is gaining popularity due to its dietary fibre content, especially β-glucans. The technological process (dough preparation, fermentation and baking) influences bread quality but also may contribute to degradation or preservation of valuable grain components. The aim of the study was to investigate the effects of different wholemeal barley flour share and bread production method on the quality of bread and non-starch polysaccharides content and solubility.Barley enriched bread contained more both soluble and insoluble dietary fibre and β-glucans, products of 40% barley share contained 67% more total dietary fibre and 160% more β-glucans than control. However, barley incorporation decreased the amount of soluble arabinoxylans. High barley contents contributed to the breads’ volume reduction by 14% and change in their crumb and crust colour. However, barley enriched breads gained higher ratings of taste than wheat bread. Barley sourdough fermentation improved breads’ volume, colour and sensory properties. Sourdough fermentation also resulted in higher concentration of dietary fibre, arabinoxylans and β-glucans. The beneficial effect of barley addition to wheat bread may be successfully enhanced by using barley wholemeal sourdough fermentation.  相似文献   

4.
Nowadays, there is an increasing interest in developing foods that have functional properties. The aim of the study was to identify the effect of the particle size (PS) of dietary fiber (DF) preparations on selected for B vitamins bioaccessibility in bread. Three different levels of particle size, obtained by sieving, were used (100, 190 and 280 μm) with different dietary fiber content in bread (2.1, 7.2 and 12.3%) according to a response surface methodology experiment design. The estimation of level of thiamine and riboflavin in bread revealed that the decreasing particle size of dietary fiber could negatively influence the bioaccessibility (69.1–91.2% and 40.9–50.2%, respectively). The interaction between the DF and PS also significantly influenced (p ≤ 0.01) the bioaccessibility of niacin (60.2–70.2%) and pyridoxine (27.52–34.01%). This research shows that the optimal particle size of dietary fiber (124.12 μm) can be used in fortifying wheat bread without significantly influencing B vitamin levels and their bioaccessibility.  相似文献   

5.
The effect of replacing wheat flour by infrared stabilized rice bran (SRB) at the levels of 2.5, 5.0 and 10.0% on the content of thiamine, riboflavin, niacin, pyridoxamine, pyridoxine, minerals and phytic acid in white wheat, wheat bran, and whole grain wheat breads was investigated. The incorporation of SRB significantly increased the amount of the noted B vitamins, especially niacin, in all bread types (p < 0.05). Zinc, iron, potassium and phosphorus levels of the breads increased gradually and significantly with the inclusion of SRB (p < 0.05). Moreover, phytic acid content of the breads increased proportional to the SRB substitution dose (p < 0.05).  相似文献   

6.
Naked barley products used in bread making gain popularity as a source of both soluble and insoluble fractions of dietary fibre, especially β-glucans. The aim of the study was to investigate the effects of different naked barley flour share in rye bread formulations and dough preparation methods (Single-phase and Detmold sourdough) on non-starch polysaccharides content and solubility and antioxidant properties of products at different processing stage. Naked barley incorporation to rye contributed to the increase in dietary fibre content with higher soluble fraction share, highly enriched products in β-glucan and increased antioxidant activity of products. It also contains high amounts of arabinoxylans, but less soluble than those from rye. A Single Phase method of rye bread production resulted in higher β-glucan concentration in products and their antioxidant activity, compared to Detmold method products. The nutritional quality of bread is highly influenced by the process parameters.  相似文献   

7.
Infrared stabilized rice bran (SRB) substitution to white wheat, wheat bran and whole grain wheat breads at the levels of 2.5, 5.0 and 10.0% was evaluated in terms of proximate composition, crumb color, dietary fiber, texture and sensory attributes. An increasing tendency was observed in crude fat and ash content of the breads. Redness (+a*), yellowness (+b*) chroma and redness (a*/b*) values were increased gradually with the addition of SRB. Crumb color was found to be darker when 10% of SRB was added to the breads. SRB inclusion did not affect the content of soluble dietary fiber while it significantly increased the insoluble and total dietary fiber contents of the breads (p < 0.05). In general, whole grain wheat bread differed from the other bread types in terms of textural behavior. Based on the overall acceptability scores, white wheat and wheat bran breads were sensory accepted up to 10% of flour replacement with rice bran, while substitution levels higher than 2.5% negatively affected the sensory scores of whole grain wheat bread.  相似文献   

8.
Gluten-free bread often has low nutritive value, high glycemic index (GI) and short shelf-life. The aim of this research was to investigate the influence of sourdough addition on GI, quality parameters and firming kinetics of gluten-free bread produced by partially baked frozen technology. Sourdough was fermented with a commercial starter of Lactobacillus fermentum and added to bread batter at four levels (7.5; 15; 22.5 or 30%). We determined biochemical characteristics of the sourdough and bread chemical composition, glycemic index in vivo, physical properties and firming kinetics after final rebaking. All breads were enriched with inulin and were high in fiber (>6 g/100 g). Control bread that was prepared without sourdough had medium GI (68). Sourdough addition decreased bread GI. However, only breads with 15 and 22.5% of sourdough had low GI. Moreover, addition of 15 and 22.5% of sourdough had positively affected the quality parameters of partially baked frozen bread: specific volume increased, crumb firmness decreased and firming was delayed. In conclusion, the combined application of sourdough and partially baked frozen technology can decrease glycemic index, improve quality and shelf-life of gluten-free bread. Such breads can be recommended as a part of well balanced gluten-free diet.  相似文献   

9.
High-performance liquid chromatography was used to study the stability of folate vitamers in two types of rye breads after baking and 16 weeks of frozen storage. Bread made using sourdough seeds contained less total folate (74.6 μg/100 g dry basis, expressed as folic acid) than the whole rye flour (79.8 μg/100 g dry basis) and bread leavened only with baker’s yeast (82.8 μg/100 g dry basis). Most importantly, it was generated by a significant decrease in 5-CH3-H4folate form. The baking process caused some changes in folate distribution. Storage of breads at -18°C for 2 weeks did not have a significant effect (p < 0.05) on total folates compared to the content directly after baking. After a 5-weeks storage period, a significant decrease (p < 0.05) in the content of total folates was recorded and it dropped on average by 14% for both type of breads. After a longer period of storage (16 weeks), a 25% loss of folates in the bread made with baker’s yeast and a 38% loss in the bread fermented with sourdough seeds was found. Retention of 5-CH3-H4folate and 10-HCO-H2folate forms were much lower in the bread made with a sourdough addition than with baker’s yeast only.  相似文献   

10.
Sourdough bread: Starch digestibility and postprandial glycemic response   总被引：1，自引：0，他引：1  
To evaluate the influence of sourdough fermentation on starch digestibility in bread, four experimental breads were obtained, prepared from two different wheat flours (whole or white) by two different leavening techniques (sourdough and with Saccharomyces cerevisiae). Products were analyzed for their starch, fiber and resistant starch (RS) content and then submitted to in vitro hydrolysis with porcine alpha-amylase. On the same breads, postprandial blood glucose was evaluated in healthy human subjects. Both sourdough fermented breads gave glycaemic responses significantly lower (p < 0.001) than the corresponding products leavened with S. cerevisiae. On the contrary, the presence of fiber did not influence the glycaemic potential of breads. RS levels were higher in the sourdough products, whereas no differences were observed either in the rate of starch hydrolysis or in the degree of polymerization of the starch residues after the in vitro hydrolysis. We may conclude that sourdough fermentation is a technique able to reduce the glycaemic response to bread and that the mechanism does not seem related to the rate of starch hydrolysis.  相似文献   

11.
Glycemic responses to most of the conventional breads are high, including breads made of wholemeal flour. Baking technology is known to affect these responses. The aim of the present study was to investigate effects of xylanase enzyme treatment and sourdough fermentation in wholemeal wheat bread baking on postprandial glucose and insulin responses and on in vitro protein digestibility. The wheat breads were made of 100% flour from peeled kernels by a straight dough or sourdough fermentation method, and with or without using xylanase during mixing of dough. Standard white wheat bread was used as a reference. All test bread portions contained 50 g available carbohydrate and were served in random order to eleven insulin resistant subjects. Blood samples for measuring glucose and insulin concentrations were drawn over 4 h. The sourdough wholemeal wheat bread resulted in the lowest postprandial glucose and insulin responses among the four tested breads (treatment × time; p = 0.000 and p = 0.022, respectively). There were differences in solubility and depolymerisation of protein and arabinoxylan among the breads but these did not fully explain the in vivo findings. In conclusion, the health effects of wholemeal wheat bread can be further improved by using sourdough process in breadmaking.  相似文献   

12.
Nejayote is the wastewater from the alkaline-cooking of maize and its solids are rich in dietary fiber (45.3%), calcium (5.7%) and ferulic acid (219 mg/100 g). Nejayote solids were used to develop a food additive (NS) consisting of 80% nejayote solids and 20% gluten. NS was incorporated at 3, 6 or 9%, in wheat flour to increase the dietary fiber, calcium, phenolics and antioxidant capacity of breads. The addition of 9% NS did not affect overall baking performance and bread quality but increased dietary fiber up to 54% in composite breads. Moreover, enriched breads contained about 745 times more free ferulic acid and increased approximately 70% their antioxidant capacity. Two slices of bread (64 g) supplemented with 9% of NS provided 29% of the recommended calcium intake. Thus, the NS could be used as a value-added food-ingredient for the preparation of composite bakery-products with improved dietary fiber, calcium, nutraceuticals and antioxidant properties.  相似文献   

13.
The development of anin vitroenzymic batch method for pretreatment of cereal samples prior toin vitrofermentation is presented. A statistical experimental design is described and the importance of bile and pepsin for the digestibility of starch was investigated. Day-to-day variation was studied by measuring glucose released and total starch in the digestion residue of rye flour. Four samples, wholemeal rye flour and bread, wholemeal and white wheat breads, were tested to evaluate the performance of the digestion procedure. Pepsin and bile enhanced the hydrolysis of slowly digestible starch. The extent of starch hydrolysis in rye and wheat breads (93–95%) was reproducible and about the same as using thermostablealpha-amylase. More soluble fibres were released from the wholemeal rye bread than from the wholemeal wheat bread. The procedure is an efficient method for the removal of starch and protein under physiological conditions prior toin vitrofermentation. The method can also be used as a tool for studying the solubility of dietary fibre (DF).  相似文献   

14.
In Poland bread as a staple food both made from wheat and rye flour can be a potential product for future fortification with folic acid. The objective of the study was to examine the effect of fermentation and baking on added folic acid and some endogenous folates stability during breadmaking of rye and wheat breads. Breads were produced using the formulation containing enriched flour with 0.2 mg folic acid/100 g product, baker’s yeast and additionally ascorbic acid for wheat bread and lactic acid for rye bread. Folates were extracted with Hepes/Ches buffer (pH = 7.85) followed by destruction of matrix by amylase and protease and deconjugation with rat serum conjugase. Affinity chromatography (FBP bovine milk) was used to purify and concentrate samples. The folates were separated by HPLC with C18 column and with a combination of fluorescence and UV detection. For both rye and wheat breads there was a decrease of folic acid from flour to bread stage. The total losses depend on baking process and ranged from 12 to 21%. Some changes in the level of different native folate forms during the stage of baking process were also observed.  相似文献   

15.
Bran is a good source of dietary fibre, phytochemicals, and also protein, but highly insoluble and recalcitrant structure of bran hinders accessibility of these components for gastrointestinal digestion. In the present work, influence of bioprocessing on the microstructure and chemical properties of rye bran and wheat bread fortified with the rye bran were studied. In vitro protein digestibility, and release of short chain fatty acids (SCFA) and ferulic acid in a gut model were studied. Bioprocessing of rye bran was performed with subsequent treatments with cell-wall hydrolysing enzymes (40 °C, 4 h) and yeast fermentation (20 °C, 20 h). Bioprocessing of rye bran resulted in reduced total dietary fibre content, caused mainly by degradation of fructan and β-glucan, and increased soluble fibre content, caused mainly by solubilisation of arabinoxylans. Microscopic analysis revealed degradation of aleurone cell wall structure of the bioprocessed rye bran. Bioprocessing caused release of protein from aleurone cells, assessed as a larger content of soluble protein in bran and a higher hydrolysis rate in vitro. Bioprocessed bran had also faster SCFA formation and ferulic acid release in the colon fermentation in vitro as compared to native bran.  相似文献   

16.
The growing interest in the benefits of wholegrain products has resulted in the development of baked products incorporating less utilised and ancient grains such as, millet, quinoa, sorghum and teff. However, addition of wholegrains can have detrimental effects on textural and sensory bread product qualities.Enzymes can be utilised to improve breadmaking performance of wholegrain flours, which do not possess the same visco-elastic properties as refined wheat flour, in order to produce a healthy and consumer acceptable cereal product.The effects of Teff grain on dough and bread quality, selected nutritional properties and the impact of enzymes on physical, textural and sensory properties of straight dough and sourdough Teff breads were investigated.Teff breads were prepared with the replacement of white wheat flour with Teff flour at various levels (0%, 10%, 20%, and 30%) using straight dough and sourdough breadmaking. Different combinations of enzymes, including xylanase and amylase (X + A), amylase and glucose oxidase (A + GO), glucose oxidase and xylanase (GO + X), lipase and amylase (L + A) were used to improve the quality of the highest level Teff breads. A number of physical, textural and sensory properties of the finished products were studied. The nutritional value of breads was determined by measuring chemical composition for iron, total antioxidant capacity, protein, fibre and fat. The obtained results were used to estimates intakes of nutrients and to compare them with DRIs.The incorporation of Teff significantly (P < 0.05) improved dietary iron levels as 30% Teff breads contained more than double the amount of iron when compared to corresponding wheat bread (6 mg/100 g v 2 mg/100 g). Addition of Teff also significantly (P < 0.05) improved total antioxidant capacity from 1.4 mM TEAC/100 g to 2.4 mM TEAC/100 g. It was estimated that an average daily allowance of 200 g of Teff enriched bread would contribute to DRIs in the range of 42-81% for iron in females, 72-138% for iron in males; 38-39% for protein in males, 46-48% for protein in females; and 47-50% of fibre in adults.The major challenge was encountered in producing the highest level of Teff bread with good textural and sensory attributes. Increasing the level of Teff significantly (P < 0.05) increased dough development time, degree of softening, crumb firmness and bitter flavour whilst decreasing the dough stability, specific loaf volume and overall acceptability of the bread. Teff breads produced with the addition of enzyme combinations showed significant improvements (P < 0.05) in terms of loaf volume, crumb firmness, crumb structure, flavour and overall acceptability in both straight dough and sourdough breadmaking.  相似文献   

17.
This study compared the concentration of angiotensin-converting enzyme (ACE) inhibitory peptides at different stages of the bread-making process, including kneading, proofing, and final products. Steamed bread, baked bread, and soda crackers were produced with 3–20% addition of rye malt sourdoughs to assess products differing in their thermal treatment. Eight tripeptides with known or predicted ACE-inhibitory activity were quantified by LC/MS in multiple reaction monitoring (MRM) mode. In wheat sourdough and rye-malt gluten sourdough, IPP was the predominant tripeptide at 58 and 473 μmol kg−1, respectively, followed by LQP, IQP, and LPP. During the bread-making process, peptide concentrations were modified by enzymatic conversions at the dough stage and by thermal reactions during baking. The concentrations of IPP, LPP and VPP remained stable during dough preparation but decreased during thermal treatment; the concentrations of other peptides were changed at the dough stage but remained relatively stable during baking. The cumulative concentration of 8 ACE-inhibitory peptides in steamed bread and bread crumb exceeded 60 μmol kg−1, while soda crackers contained less than 3 μmol kg−1. The peptide levels in bread thus likely meet in vivo active concentrations.  相似文献   

18.
The use of sourdough, even in combination with cryoprotectant (skim milk, sucrose and trehalose), conventional additives (guar gum, diacetyl tartaric acid esters of monoglycerides, ascorbic acid), honey or fructose and glucose, in frozen dough technology was investigated. After frozen storage, the leavening performance of doughs, and the hardness and texture of breads were compared to those of an unfrozen dough, and to those of a conventional frozen dough. All frozen doughs showed a longer fermentation time and a lower volume increase, with respect to unfrozen dough. When sourdough was combined with cryoprotectant, honey or both, the leavening performance improved compared to the use of sourdough alone. Compared to the conventional frozen dough, higher leavening performance was reached combining sourdough with cryoprotectant alone or together with honey. Sourdough combined with honey, fructose and glucose, honey and cryoprotectant, or conventional additives decreased bread hardness compared to the unfrozen dough bread and to the conventional frozen dough bread. Independently from the use of sourdough, conventional additives allowed to reach a specific volume not significantly different from that of unfrozen dough bread, and breads containing honey were characterized by low values of hardness and by high values of red index.  相似文献   

19.
The potential of sourdough to improve bread quality of barley and oat enriched wheat breads may depend on the characteristics of the added flour (cereal type, variety, extraction rate). We compared the effect of different barley flours and oat bran (substitution level 40%), unfermented and as sourdoughs (20% of total flour), on composite wheat dough and bread characteristics by combining empirical rheological analyses (DoughLab, SMS/Kieffer Dough and Gluten Extensibility Rig) with small-scale baking of hearth loaves. Whole grain barley flour sourdough increased resistance to extension (Rmax) of the dough and improved the form ratio of hearth loaves compared to unfermented whole grain barley flour. However, sourdough showed little effect on the breads prepared with sifted barley flour or oat bran. The breads made with oat bran showed highest bread volume, lowest crumb firmness and highest β-glucan calcofluor weight average molecular weight (MW). The heat treatment of oat bran inactivated endogenous enzymes resulting in less β-glucan degradation. High MW β-glucans will increase the viscosity of the doughs water phase, which in turn may stabilise gas cells and may therefore be the reason for the higher bread volume of the oat bran breads observed in our study.  相似文献   

20.
In this study, the effect of immature wheat flour (IWF) on the fermentation activity of lactic acid bacteria (LAB) and on the nutritional quality properties of bread were evaluated. IWF was added in the as the ratio of 10g/100g in sourdough fermentation medium, and the fermentation activity (total LAB, pH, titration acidity (TA), and total reducing sugar (TRS)) of LAB cultures was monitored. Additionally, some physical quality characteristics (specific volume, texture profile and colour value), estimated glycaemic index (eGI), rapidly digestible starch (RDS), slowly digestible starch (SDS), and the total dietary fibre content of sourdough bread were determined. According to the statistical test, it was revealed that the IWF addition stimulated LAB growth and increased their fermentation activity. The pH of the fermentation medium decreased from 6.57 to 3.50, and TA raised from 0.13% to 1.2% in 48 h. The highest TRS content was determined in IWF enriched sourdough samples, and as a result of this, the eGI of sourdough bread increased. Compared to the control sample, the SDS and total dietary fibre content were higher in IWF added sourdough bread, and a positive correlation was noted between these two components. IWF utilisation of sourdough bread formulation increased the hardness value by nearly 50%.  相似文献   

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