Barley Sourdough Research Articles

Sourdough Fermentation of Oat and Barley Flour with Bran and Its Application in Flatbread Made with No-Time and Dough Retardation Methods

Dough retardation is commonly used to extend dough shelf-life, but it poses a challenge for flatbreads due to their large surface. This study explored the sourdough fermentation of oats and barley, addressing challenges in the retardation of dough for flatbread. Sourdough, using flour only or flour blended with bran (3:1), was fermented with a LIVENDO LV1 starter at 30 °C for 24 h. The pH value, microbial viable cell count, total titratable acidity and organic acids concentration of the sourdough were measured. The properties of dough and flatbread, depending on the retardation time (24 h and 48 h), sourdough type (oat or barley) and sourdough level (30% or 50% dough weight), were investigated. Oat flour’s limited acidification improved with the inclusion of bran, resulting in a desirable pH, TTA, and lactic to acetic acid ratio after 15 h of fermentation, which were comparable to results achieved with barley sourdough. The sourdough addition slowed down the enzymatic browning of dough during retardation. Dough retardation at 24 h reduced the phytates content (32–38%) and crumb hardness (9–16%), depending on the sourdough type and level. In dough retardation, β-glucans were degraded by up to 9% in the case of oats and by up to 28% in the samples with barley. Overall, adding oat or barley sourdough at a 30% dough weight can be recommended to enhance flatbread’s nutritional value and prolong its shelf life.

Enhancing the highland barley-wheat dough network structure and bread quality using freeze-dried sourdough powder with inulin as a protectant

In this study, freeze-dried highland barley sourdough powder containing inulin (SPN) was prepared, and its stability during storage, as well as the effects of SPN on dough network structure and bread quality, were investigated. Results showed that SPN retained a higher number of viable lactic acid bacteria and acid-producing ability in comparison to sourdough powder without inulin when stored at 4 °C for 60 d. The use of SPN was advantageous in the formation of gluten network structure in the dough. Bread prepared with SPN (B2) exhibited a larger specific volume and a softer texture than the highland barley-wheat (1:8, w/w) bread prepared without sourdough (B0) (P < 0.05) and the one prepared with fresh highland barley sourdough (B1) (P > 0.05). Sourdough usage decreased in vitro starch digestibility, yet increased protein digestibility and antioxidant activity, with no significant differences between B1 and B2. Ultimately, B2 showed the highest overall acceptability. The positive effects of SPN may provide insights into future innovations in this area.

Composition of Polysaccharides in Hull-Less Barley Sourdough Bread and Their Impact on Physical Properties of Bread.

The complex of polysaccharides of the grain transforms during processing and modifies the physical and chemical characteristics of bread. The aim of the research was to characterize the changes of glucans, mannans and fructans in hull-less barley and wholegrain wheat breads fermented with spontaneous hull-less barley sourdough, germinated hull-less barley sourdough and yeast, as well as to analyze the impact of polysaccharides on the physical parameters of bread. By using the barley sourdoughs for wholegrain wheat bread dough fermentation, the specific volume and porosity was reduced; the hardness was not significantly increased, but the content of β-glucans was doubled. Principal component analysis indicates a higher content of β-glucans and a lower content of starch, total glucans, fructans and mannans for hull-less barley breads, but wholegrain wheat breads fermented with sourdoughs have a higher amount of starch, total glucans, fructans and mannans, and a lower content of β-glucans. The composition of polysaccharides was affected by the type of flour and fermentation method used.

Mycobiome characterization of “Ghimisone”, a Sardinian ancient barley sourdough traditionally used in Sardinia for making “Ogliathu” bread

Mycobiome characterization of “Ghimisone”, a Sardinian ancient barley sourdough traditionally used in Sardinia for making “Ogliathu” bread

Determination of Technological Parameters and Characterization of Microbiota of the Spontaneous Sourdough Fermentation of Hull-Less Barley.

The development of microorganisms of sourdough and biodiversity of microbiota can be influenced by changing the parameters of the technological process such as the ratio of flour and added water, the fermentation temperature and time. The Box–Behnken design methodology was used to determine the optimal parameters for the three-phase spontaneous backslopping fermentation process of hull-less barley sourdough, as well as to characterize the microbiological diversity. The optimized parameters of backslopping fermentation are flour and water ratio 1:1.13, temperature 30 °C, time 24 h in the 1st backslopping; the inoculate, flour and water ratio 1:1:1.3, temperature 31 °C, time 14 h in the 2nd backslopping, and the inoculate, flour and water ratio 1:1:1.5, and temperature 28.5 °C, time 12 h in the 3rd step of backslopping. In the controlled spontaneous fermentation environment in three backslopping steps, the microbiological research of hull-less barley sourdough has confirmed the dominance of species Pediococcus pentosaceus in the 3rd backslopping step of spontaneous fermentation. The developed spontaneous hull-less barley sourdough is consistent with the number of lactic bacteria and yeasts in line with that seen by the active sourdough.

Effect of starter culture sourdough prepared with Lactobacilli and Saccharomyces cerevisiae on the quality of hull-less barley-wheat bread

The aim of the present study was to investigate the microbial and technological characterization of barley-wheat flour (with 25%, 50%, 75% wheat flour added) breads made from hull-less barley sourdough that was prepared with a starter culture of Lb. plantarum SAB15, Lb. brevis SAB31 and S. cerevisiae SAM1-4. The yeasts isolated from spontaneous hull-less sourdough were sequenced with 26S rRNA gene via identification of the dominant species of S. cerevisiae with FTIR. Hull-less barley, with 13.6% protein, 1.47% ash, 66.15% water absorption and 21 ml sedimentation value, was added to wheat flour and protein, water absorption, and ash values decreased while sedimentation values increased. Hull-less barley-wheat bread samples containing starter culture was obtained with higher volume, specific volume and lower hardness than breads containing spontaneous culture. Especially breads with 25% and 50% barley mix were found to be the best ratios for hull-less barley bread. Although bread containing 75% and 100% barley flour scored low, those containing starter culture scored positively in terms of hardness and chewiness, and were accepted by consumers. With more barley added, there was higher a* and lower b* in the bread, while the breads with starter culture were found to be less yellow and red.

Reinvigorating Modern Breadmaking Based on Ancient Practices and Plant Ingredients, with Implementation of a Physicochemical Approach.

In this study, the potential use of ancient plant ingredients in emerging bakery products based on possible prehistoric and/or ancient practices of grinding and breadmaking was explored. Various ancient grains, nuts and seeds (einkorn wheat, barley, acorn, lentil, poppy seeds, linseed) were ground using prehistoric grinding tool replicas. Barley-based sourdough prepared by multiple back-slopping steps was added to dough made from einkorn alone or mixed with the above ingredients (20% level) or commercial flours alone (common wheat, spelt, barley). Sieving analysis showed that 40% of the einkorn flour particles were >400 μm, whereas commercial barley and common wheat flours were finer. Differential scanning calorimetry revealed that lentil flour exhibited higher melting peak temperature and lower apparent enthalpy of starch gelatinization. Among all bread formulations tested, barley dough exhibited the highest elastic modulus and complex viscosity, as determined by dynamic rheometry; einkorn breads fortified with linseed and barley had the softest and hardest crust, respectively, as indicated by texture analysis; and common wheat gave the highest loaf-specific volume. Barley sourdough inclusion into einkorn dough did not affect the extent of starch retrogradation in the baked product. Generally, incorporation of ancient plant ingredients into contemporary bread formulations seems to be feasible.

Biodiversity and techno-functional properties of lactic acid bacteria in fermented hull-less barley sourdough

The aim of this study was to characterize the biodiversity of lactic acid bacteria (LAB) isolated from spontaneously-fermented hull-less barley sourdough and to determine its technological properties. Biodiversity was investigated by analysis of colonies isolated from sourdough on four different agar media. Of the 80 isolates, 67 were rapidly pre-identified as LAB using Fourier transforms infrared spectroscopy (FTIR). As a result of cluster analysis, 32 lactic acid bacteria chosen from different branches were identified. According to the polymerase chain reaction (PCR) results, 9 different species were identified: Pediococcus (dominant species), Lactobacillus curvatus, Lactobacillus brevis, Lactobacillus plantarum, Lactobacillus fermentum, Lactobacillus musae, Lactobacillus paralimentarius, Leuconostoc mesenteroides and Lactobacillus equigenerosi. The most species and strain diversity among the media was determined in ModMRS environment. Unlike other studies about hull-less barley, Lactobacillus equigenerosi was identified in this study. LABs were identified with salt and acid tolerance. Generally, different levels of antibacterial activity in these species were shown against (rope spoilage) food borne pathogens. The greatest antimicrobial effect was observed for Pediococcus acidilactici SAB26, Lactobacillus plantarum SAB15 and Pediococcus acidilactici SAB13 compared to the other strains. Pediococcus species were found to have the highest antifungal effect against Penicillium carneum, Aspergillus flavus and A. niger. The phytase activity of LAB, which increases mineral bioavailability, was observed to be highest in Lactobacillus plantarum, Pediococcus pentosaceus, and Leuconostoc mesenteroides.

Effects of temperature, pH, and bile salt on antimicrobial activity of bacteriocin-like substances obtained from barley sourdough LAB

This study aimed to investigate the effects of temperature (4, 85, 121 °C), pH (2, 4, 11), and bile salt (0.3, 0.6, 1%)—as common conditions of gastrointestinal tract or thermal food processing—on antimicrobial activity of bacteriocin-like substances (BLS) obtained from barley sourdough lactic acid bacteria (LAB) against some of food-borne pathogens. In addition, the safety of LAB isolates was also evaluated. The isolates were identified by sequencing of PCR products as Lactobacillus brevis, Lactobacillus curieae, Pediococcus stilesii and Weissella cibaria. At low and high temperatures and pH values and at the presence of bile salt, BLS of the LAB isolates showed remarkable antimicrobial activity against studied indicator bacteria. Furthermore, BLS of L. curieae treated in pH 4 among all pH treatments, BLS of L. brevis and P. stilesii in 1% bile salt among all bile salt treatments, and finally BLS of L. curieae and P. stilesii treated at 4 °C among all temperature treatments were the most effective, respectively, against Aspergillus niger and A. flavus. The safety results demonstrated that consumption of LAB isolates had no adverse effects on general health of mice. Body weight of mice was increased by administration of LAB during 3 weeks, such as control group. Liver enzyme activities of mice treated with the LAB isolates had also insignificant difference with control mice.

Frozen stored barley sourdough: stability and application to wheat bread

Frozen stored barley sourdough: stability and application to wheat bread

The potential of naked barley sourdough to improve the quality and dietary fibre content of barley enriched wheat bread

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.

Application of Pediococcus acidilactici LUHS29 immobilized in apple pomace matrix for high value wheat-barley sourdough bread

The aim of this study was to evaluate the potential use of Pediococcus acidilactici LUHS29 immobilized in apple pomace in case to apply in barley sourdough fermentation for functional bread production. The strain was phenotypically characterized by the growth and acidification rate, carbohydrate metabolism and resistance to acidic conditions. The effect of immobilized bacterial cells on antioxidant properties of barley sourdough and on the acrylamide content in wheat-barley bread was analyzed. The phenotypic and molecular testing indicates the P. acidilactici having a versatile carbohydrate metabolism and acid resistance, showing 42.7% of viable cells surviving after incubation at low pH as compared to initial number (7.5 log10 CFU/g). Fermentation with immobilized strain increased by 15.3% the production of LA compared to spontaneous fermentation (24.2 g/kg), and the ability to produce l-lactic acid contents up to 92.7% from the total LA. The use of P. acidilactici for barley sourdough fermentation increased β-glucan solubility by 1.3–5.1%, moreover, the total phenolic compounds (TPC) content and radical scavening activity were found higher up to 34.6% and 79.7%, respectively. Addition of barley sourdough at a level of 10% could reduce acrylamide content in bread up to 44% and retard bread staling process. The application of immobilized in apple pomace bacterial cells could have the future impact for the food industry due to the bioactive potential.

Parameters of rye, wheat, barley, and oat sourdoughs fermented with Lactobacillus plantarumLUHS135 that influence the quality of mixed rye–wheat bread, including acrylamide formation

AbstractA Lactobacillus plantarum strain was used for the production of rye, wheat, barley, and oat sourdoughs, and the influence of different sourdoughs on mixed rye–wheat bread quality parameters and acrylamide formation was evaluated. L. plantarum LUHS135 demonstrated versatile carbohydrate metabolism, good growth and acidification rates, and the ability to excrete amylolytic and proteolytic enzymes in various cereal sourdoughs. The same starter and different cereal substrates allow to produce sourdoughs showing different characteristics. The type of sourdough and its quantity had significant influence on acrylamide content in bread (P ≤ 0.0001), and using 5% or 10% of wheat sourdough, 5%, 15%, or 20% of barley sourdough, and 5% or 15% of oat sourdough, it is possible to reduce acrylamide content in bread. Thus, manufacturers need to take into account application of apparent technological approaches for acrylamide in bread reducing.

Influence of Barley Sourdough and Vacuum Cooling on Shelf Life Quality of Partially Baked Bread.

Driven by the bakery industry urge to satisfy consumer demand for fresh, diverse and high quality bakery products, we investigated the influence of barley sourdough and vacuum cooling on shelf life quality of partially baked bread stored in modified atmosphere packaging at ambient conditions. Barley sourdough was fermented with Lactobacillus reuteri (DSM 20016, F275). Partially baked bread with sourdough was microbiologically acceptable during 30 days of storage, while bread without sourdough had detectable mould on the 30th day. Stored bread samples were rebaked after 1, 8, 15, 22 and 30 days to determine moisture content, physical and sensorial properties. Moisture loss (5%) was detected on the 15th day, after which it remained stable until the end of investigated storage period. Nevertheless, textural quality of stored bread continuously declined due to crumb firming. Bread flavour did not change during mould-free storage time. The principal component analysis identified major differences in the flavour of sour and control bread, also in crumb firmness and moisture content of samples. This study indicates the positive role of barley sourdough fermented with L. reuteri in improving crumb texture for at least 15 days, and ensuring mould- and bacteria-free partially baked bread for 30 days. Vacuum cooling combined with sourdough improved bread shape, porosity, and reduced sour taste, crust colouring and crumbliness. Hence, it can successfully extend shelf life quality of partially baked bread in modified atmosphere packaging.

Community dynamics and metabolite target analysis of spontaneous, backslopped barley sourdough fermentations under laboratory and bakery conditions

Barley flour is not commonly used for baking because of its negative effects on bread dough rheology and loaf volume. However, barley sourdoughs are promising ingredients to produce improved barley-based breads. Spontaneous barley sourdough fermentations were performed through backslopping (every 24h, 10days) under laboratory (fermentors, controlled temperature of 30°C, high dough yield of 400) and bakery conditions (open vessels, ambient temperature of 17–22°C, low dough yield of 200), making use of the same batch of flour. They differed in pH evolution, microbial community dynamics, and lactic acid bacteria (LAB) species composition. After ten backsloppings, the barley sourdoughs were characterized by the presence of the LAB species Lactobacillus fermentum, Lactobacillus plantarum, and Lactobacillus brevis in the case of the laboratory productions (fast pH decrease, pH<4.0 after two backslopping steps), and of Leuconostoc citreum, Leuconostoc mesenteroides, Weissella confusa and Weissella cibaria in the case of the bakery productions (slow pH decrease, pH4.0 after eight backslopping steps). In both sourdough productions, Saccharomyces cerevisiae was the sole yeast species. Breads made with wheat flour supplemented with 20% (on flour basis) barley sourdough displayed a firmer texture, a smaller volume, and an acceptable flavour compared with all wheat-based reference breads. Hence, representative strains of the LAB species mentioned above, adapted to the environmental conditions they will be confronted with, may be selected as starter cultures for the production of stable barley sourdoughs and flavourful breads.

Cheese whey treated by membrane separation as a valuable ingredient for barley sourdough preparation

Utilisation of cheese whey for production of healthier food has been the main task of this study. Cheese whey, which is often considered as a waste material, was treated by a series of processes including fermentation, membrane filtrations, mixing with barley flour, drying, and/or extrusion to produce barley sourdough.In the first series of experiments, the effect of membrane ultrafiltration (UF) and nanofiltration (NF) on separation of whey components has been studied. Non-fermented sweet cheese whey was treated by pilot-plant membrane ultrafiltration (50kDa tubular ceramic membrane, TAMI Industries, France), followed by three step diafiltration to minimise losses of lactose, glucose, galactose, and organic acids (namely lactic acid) in retentate. The UF permeates were used for the subsequent nanofiltration and diafiltrations (spiral wound membrane NF 270-2540, Filmtec, Dow Chemicals, USA). The results showed high recovery of proteins (81%) during UF and reduction of lactose and propionate losses by using diafiltration. Rejections of components on the NF membrane were: 93% lactose, 77% galactose, and 76% lactic acid. However, the diafiltration on the NF membrane reduced the relative recovery both for carbohydrates and organic acids.In the second series of experiments, cheese whey was concentrated by reverse osmosis (RO) and the obtained retentate was fermented with Lactobacillus plantarum, Lactobacillus sanfranciscensis and Propionibacterium freudenreichii subsp. freudenreichii. Part of the fermented whey was mixed with barley flour and dried by cold air fluid drying to produce sourdough pellets. The other part of fermented whey was filtered by nanofiltration and both permeate and retentate were sprayed on the surface of sourdough pellets in several layers and dried again. The extrusion of a mixture containing barley flour and fermented whey was tested for pellet production as well. The main aims were to obtain sourdough rich in natural preservatives, and maintain the present microorganisms active. That is why all the technological processes, including drying, were carried out under low temperatures. The content of organic acids (lactic, acetic and propionic) was analysed in final sourdough samples.

Effects of flour from different barley varieties on barley sour dough bread

Twenty flours from 16 different barley varieties cultivated in 1990 and 1992, and a Swedish reference flour, were fermented by Lactobacillus plantarum A1 to sour doughs. Barley breads ( 40% barley 60% wheat flour ) from each flour type were baked with and without an admixture of barley sour dough in order to investigate how the sour dough admixture would affect the baking properties. A trained panel carried out sensory evaluation by conventional profiling on breads made from three of the barley varieties and the Swedish reference flour, made with and without sour dough admixture. The barley varieties influenced both the sour dough properties and the properties of the barley bread. The pH of bread with sour dough ranged from 4.6 to 4.8 as compared to 5.4 to 5.6 in bread without sour dough. The acidity of the breads with sour dough ranged from 4.1 to 5.0 ml NaOH/ 10 g bread crumb as compared to 2.4 to 3.6 in breads without sour dough. In 14 of the twenty bread types an addition of sour dough lowered the bread volume. Breads with a sour dough admixture scored higher for total taste and acidulous taste than breads without sour dough. The β-glucan content of the flours had no significant influence on the sour dough or the sensory characteristics of the bread, except for the breadcrumb colour.

Influences of lactic acid bacteria on technological, nutritional, and sensory properties of barley sour dough bread

Barley bread was baked with and without admixture of barley sour doughs, individually fermented with seven starter cultures containing lactic acid bacteria (including two with β-glucanase activity). The aim of the study was to investigate how starter cultures influenced the baking-technological, nutritional and sensory properties of barley bread. Could degradation of β-glucans caused by sour dough admixture result in bread that was more easy to chew? The starter culture influenced the volume yield, the total titratable acidity (S °) and the sensory properties. The amounts of lactate and acetate ranged from 0.20 to 0.26 and 0.03 to 0.08 g/100 g sour dough bread, respectively. The total titratable acidity in the sour dough breads varied between 4.1 and 5.4 ml 0.1 N NaOH/10 g bread. There were negative correlations between barley taste and total titratable acidity (S °). The acidulous taste of the sour dough breads seemed to mask the barley taste. The phytate of the barley sour dough breads was reduced below 0.5 μ mol g , which does not inhibit mineral absorption, irrespective of starter culture. There was no significant difference in the total content of β-glucans between bread made with and without admixture of sour dough, irrespective of starter culture, rejecting the hypothesis that barley bread made with sour dough would be more easy to chew.

II-22. Sensory properties of barley sour dough bread made from different barley varieties

II-22. Sensory properties of barley sour dough bread made from different barley varieties