Search Results (298)

Sourdough fermentation, a time-honored biotechnology known for enhancing the texture, flavor, and nutritional quality of steamed bread, has yet to be fully leveraged for optimizing microbial synergy, particularly between Kazachstania humilis (KH) and Lactobacillus plantarum (LP). In this study, we systematically evaluated the impact of fermentation dynamics on sourdough properties and steamed bread quality using single-strain (KH or LP) and co-fermentation (LP+KH) strategies. Our findings demonstrated that LP+KH co-fermentation significantly accelerated sourdough acidification, achieving the lowest pH (3.8) and highest total titratable acidity (TTA, 14.2 mL) among all groups. This synergy also enhanced dough gas retention, resulting in an 11.89% and 7.25% increase in specific volume compared to LP and KH monocultures, respectively. Steamed bread produced from the co-fermented dough exhibited markedly improved textural qualities, including reduced hardness, gumminess, and chewiness, along with increased cohesiveness. Moreover, the water content in bread from the LP+KH group remained significantly higher, contributing to better freshness retention over time. In conclusion, LP and KH co-fermentation offers a promising approach for elevating the quality and shelf-life of steamed bread, revealing untapped potential in microbial synergy during sourdough fermentation. Full article

The quality of artisanal bread is strongly influenced by sourdough fermentation, where aroma development and microbial stability are key factors. This study evaluates the use of an electronic nose (E-nose) to monitor cold fermentation, integrating it with microbiological analysis and gas chromatography–mass spectrometry (SPME-GC-MS) to characterize the dough’s volatile profile. A clear correlation was observed between microbial dynamics, pH reduction (from 5.8 to 3.8), and the evolution of volatile compounds, with notable increases in acetic acid (up to 12.75%), ethanol (11.95%), and fruity esters such as isoamyl acetate (33.33%). Linear discriminant analysis (LDA) explained 96.31% of the total variance in a single component, successfully separating the fermentation stages. An artificial neural network discriminant analysis (ANNDA) model achieved 95% accuracy in the validation phase. These results confirm the E-nose’s ability to track biochemical transformations in real time and identify optimal fermentation points. This approach enhances quality control and sensory standardization in sourdough-based bakery products. Full article

Humulus lupulus L. (common hop) is a herbaceous plant whose female inflorescences, commonly called hop “cones”, are traditionally used in Bulgaria to prepare sourdough starters or “kvass”. Drawing from a review of historical and linguistic sources and ethnographic information collected by the authors, this study aims to define the traditional preparation of bread with hop sourdough, starting from the preparation of the hop cone decoction. Archival materials and early cookbooks attest to a rich tradition where hop-infused bread was valued for its distinctive flavor and preservative qualities. Fieldwork conducted in Bulgaria and among Bulgarian diasporas in Moldova provided insights into the continuity of these practices, underscoring the persistence of these traditional preparations despite modern industrial pressures. Ethnographic interviews and participant observations highlighted the ritualistic preparation of hop kvass and its role in community identity. The effect of hops on dough’s rheological properties and the quality features of bread were also reviewed. An increase in dough stability and resistance to elongation were generally reported, with a reduction in bread volume and porosity, especially with hop sourdough levels above 30%, but the incorporation of bioactive molecules was responsible for antioxidant, antimicrobial, and flavoring properties. Possible prospects for using hops in the food industry, based on the biological properties of this resource-rich plant, are outlined with a multidisciplinary approach. Full article

This study aimed to explore the genetic and functional diversity of Lactiplantibacillus plantarum (Lpb. plantarum) strains from wild fermented foods to identify traits that are useful for food innovation. The growing demand for clean-label, plant-based, and functionally enriched fermented foods exposes the limitations of current industrial fermentation practices, which rely on standardized lactic acid bacteria (LAB) strains with limited metabolic plasticity. This constraint hinders the development of new food formulations and the replacement of conventional additives. To address this gap, 343 LAB strains were analyzed, including 69 Lpb plantarum strains, isolated from five minimally processed, spontaneously fermented matrices: fermented millet, kombucha, and sourdough (plant-based), wild fermented mountain milk, and natural whey starter (animal-based). Whole-genome sequencing was performed to assess phylogenetic relationships and to annotate genes encoding carbohydrate-active enzymes (CAZymes) and antimicrobial compounds. The results revealed a marked strain-level diversity. Glycoside hydrolase (GH) families GH13 and GH1 were widely distributed, while GH25 and GH32 showed variable presence across clusters. Strains grouped into clusters enriched with plant-based isolates exhibited distinct CAZyme profiles adapted to complex carbohydrates. Clusters with animal-based strains exhibited a broader gene repertoire related to bacteriocin biosynthesis. These findings highlight the untapped potential of wild fermented food environments as reservoirs of Lpb. plantarum with unique genomic traits. Harnessing this diversity can expand the functional capabilities of starter cultures, promoting more sustainable, adaptive, and innovative fermentation systems. This study underscores the strategic value of underexploited microbial niches in meeting the evolving demands of modern food production. Full article

The wastage of by-products generated in the food industry is an issue that should be addressed by determining a second use for these products, with sourdough fermentation being the most popular technology used. The aim of this research was to evaluate the impact of adding agave bagasse (AB) and Lactococcus lactis NRRL B-50307 to sourdough that was later used in the formulation of bread rolls. Five treatments were tested: B1: wheat flour; BI2: wheat flour inoculated with L. lactis (1 × 10⁶ CFU/mL); C10: wheat flour + AB (10% w/w); T5: 5% AB + wheat flour inoculated with L. lactis (1 × 10⁶ CFU/mL); and T10: 10% AB + wheat flour inoculated with L. lactis (1 × 10⁶ CFU/mL). Sourdoughs were back-slopped daily for 6 days, dried in a climatic chamber, reactivated, and left to ferment for 24 h. Samples of each treatment of dried and reactivated sourdough were collected and tests for antioxidant activity (DPPH and ABTS), total amino acid content (OPA), and phenolic and flavonoid content were performed. Phenolic compounds and flavonoids decreased when the sourdough was dried (1.5 to 2.0 mg/g of quercetin); however, an increase in bioactive compounds was observed after reactivation, with the treatments with AB recording the highest values (2.5 mg/g). The DPPH and ABTS tests showed that T10 had the highest activity (25% and 23%, respectively). The OPA results showed an increment in amino acid content (2.0 mg lysine/g), indicating proteolysis. The fermentation curves showed that leavening time was achieved after 600 min of fermentation. AB addition did not affect the viscosity of the sourdough rolls. Sourdough with added AB and L. lactis provided a novel approach to achieve more sustainable baked goods. The drying process decreased the sourdough’s bioactive compounds, which were recovered after reactivation. Full article

Gluten-free flour blends, consisting of quinoa and sorghum flours, were used in the present study to prepare sourdough samples, which were characterized in terms of physical–chemical properties, the thermo-mechanical behavior of dough and bread making performance. The quinoa–sorghum flour blends (100:0, 75:25, 50:50) were fermented using two different starter cultures, consisting of Lacticaseibacillus rhamnosus, Levilactobacillus brevis and Lactiplantibacillus plantarum (SC1), and Lactobacillus acidophilus, Bifidobacterium lactis and Streptococcus thermophilus (SC2). After 20 h of fermentation at 30 °C, the acidity of the sourdoughs prepared with SC1 and SC2 was significantly higher in respect to the corresponding spontaneously fermented sample. The use of the starter culture for sourdough fermentation resulted in sourdoughs with higher glycerol and lactic acid contents, and lower ethanol and acetic acid. The empirical rheological measurements indicated that the behavior of the proteins and starch within the complex dough matrix, during mixing and heating, is influenced by both sorghum level and starter culture type. The use of the sourdough allowed the preparation of gluten-free breads with good texture and high contents of bioactive compounds. In conclusion, sourdough fermentation can be successfully used for boosting the quality of the gluten-free bread products. Full article

Roasted carob flour is a sustainable ingredient rich in dietary fiber, polyphenols, and pinitol, offering potential for both food and pharmaceutical applications. However, its high sugar content and the presence of undesirable compounds such as furans present challenges for its use in bread making. This study evaluated the effects of prolonged sourdough fermentation on roasted carob flour, with a focus on microbial dynamics and its functional and technological properties. Carob and carob–wheat sourdoughs were prepared using a mixed starter culture comprising three lactic acid bacteria (Lactiplantibacillus plantarum, Fructilactobacillus sanfranciscensis, and Lactobacillus helveticus) and three yeast species (Saccharomyces cerevisiae, Kazachstania humilis, and Torulaspora delbrueckii). The sourdoughs underwent six consecutive refreshment cycles and were analyzed to determine their pH, microbial and biochemical composition, gassing power, and volatile organic compounds (VOCs). The carob–wheat sourdough exhibited faster acidification and higher lactic acid bacteria (LAB) activity, resulting in a 90–98% reduction in the sugar content, compared to 60% in the carob sourdough. Microbial sequencing revealed that L. plantarum was the dominant species in all samples, while K. humilis and S. cerevisiae were enriched in carob and carob–wheat sourdough, respectively. Both types of sourdough demonstrated effective leavening in bread dough without the addition of commercial yeast. Fermentation also modified the VOC profiles, increasing esters and alcohols while reducing acids, aldehydes, ketones, and furans. While the antioxidant activity showed a slight decline, the pinitol content remained unchanged. These findings suggest that extended sourdough fermentation, supported by multiple refreshments, enhances the baking suitability of roasted carob flour and supports its application as a functional, sustainable ingredient. Full article

This study investigates the potential of utilising the proteolytic activity of two different strains, Levilactobacillus brevis FST140 and Pediococcus pentosaceus FST22, to assess their impact on wheat gluten proteins. A high-power ultrasound (US) treatment (850 kHz; 500 W/cm²; 35 °C) was used to activate the proteolytic system of LAB to promote gliadin-like protein degradation in wheat wholemeal-based sourdough. The proteolytic activity of L. brevis and P. pentosaceus increased two-fold with 10 and 20 min US stimulation, respectively, compared to fermentation without ultrasonication. Regarding the impact of proteolysis and sonication on gliadin proteins, fermentation with both strains reduced gliadin content in commercial gluten by an average of 77.4% compared to the untreated sample, and additional US treatment further enhanced gliadin degradation efficiency to an average of 83.5%. The combined application of US and lactic acid fermentation initiated a seven-fold decrease in wheat wholemeal flour (WF) gliadin levels compared to the untreated sample (47.2 mg/g). Furthermore, the synergistic application of US, LAB, and yeast fermentation allowed us to reduce gliadin content up to 1.6 mg/g, as well as to reduce gluten content in the sourdough up to 3 mg/g. Despite complete hydrolysis of the gliadin fraction under the combined effects of US and fermentation, glutenins were less affected by the applied treatments in all cases. The technology presented in this study offers a promising approach for producing gluten-free or low-gluten fermented products in the bread-making industry. Full article

Baking leavening agents and fermentation conditions may influence the gastrointestinal fate of nutrients in baked goods, thereby affecting their bioavailability. This study aimed to evaluate the digestibility of sourdough pizza fermented with lactic acid bacteria species (Levilactobacillus brevis, Fructilactobacillus sanfranciscensis, Leuconostoc pseudomesenteroides) and yeast, compared to traditional pizza fermented with baker′s yeast. The effects of leavening time (up to 48 h) and microbial leavening agents on the nutritional profile and digestibility of baked pizzas were investigated by examining the microbiological and physico-chemical changes in the doughs, with a particular focus on the sugar content. Additionally, the degree of protein hydrolysis and the levels of FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides, and polyols) were quantified on the cooked pizzas both before and after in vitro gastrointestinal digestion. In vitro protein digestibility was not significantly influenced by the type of microbial leavening agent used or fermentation time. However, extended fermentation, particularly with lactic acid bacteria sourdough, resulted in a notable decrease in FODMAPs, thereby enhancing the digestibility and overall health profile of the pizza for individuals sensitive to these compounds. Future research should further explore the mechanisms behind these changes and their implications for dietary recommendations. Full article

The production of functional bread has been of great interest lately to the Food Industry. Regarding this, the enrichment of bread with natural raw materials rich in phenolic antioxidants, such as fruits, has become a new trend. Likewise, the aim of the current study was to evaluate novel supplements based on freeze-dried Cornelian cherry juice, both unfermented and fermented by probiotic L. plantarum ATCC 14917, in sourdough bread production. The outcome showed that the fermented supplement led to sourdough bread with elevated nutritional features in terms of its total phenolic content (99.5 mg GAE/100 g) and antioxidant activity (213 mg TE/100 g for ABTS and 4.7 μmol TE/g for DPPH), as well as a reduction in phytic acid (93.3%) compared with all the other bread samples. In addition, the same sample contained higher amounts of lactic (2.91 g/Kg bread) and acetic acid (1.23 g/Kg), as well as formic (0.11 g/Kg), n-valeric (0.12 g/Kg) and caproic (0.05 g/Kg) acids compared with all the other samples, leading to a higher preservation time (13 days) regarding rope and mold spoilage. All breads exhibited the same sensorial characteristics, proving that the supplement did not affect bread quality. This outcome is very interesting since powdered supplements have recently been endorsed in the bread industry for enabling nutritional and technological improvements. Full article

The aim of this study was to characterize in vitro digestion of wheat breads baked with sourdough or the postponed baking method without and with arabinoxylan (AX) of different molar mass. The influence of the AX share on the rate of starch digestion, the molar mass of resistant starch (RS) and the pasting characteristics of crumb suspensions of breads baked by the sourdough and postponed baking methods were investigated. Sourdough wheat breads were characterized by contents of very slowly digestible starch (DS) of 1.3% and RS of 1% higher in the crumb, compared to breads baked by the postponed baking method. In the crumb of sourdough breads, after storage for 1 and 3 days, in all variants of the samples (especially with the 2% share of high molar mass AXs), the content of the rapidly digested starch (RDS) fraction decreased, the content of the slowly digestible (SDS) and DS fractions did not change significantly, while the content of the RS fraction increased. In addition, the RS fraction present in the crumb of sourdough breads was generally characterized by a lower molar mass than the RS isolated from the crumb of breads baked by the postponed baking method. The crumb of wheat breads baked using sourdough was characterized by higher viscosity, compared to those baked by the postponed baking method. Full article

In the present study, Lactiplantibacillus plantarum G8, exhibiting higher antifungal activity, and G12, displaying weaker antifungal activity, were isolated from naturally fermented wheat sourdough. Their impacts on bread quality and shelf life were subsequently investigated. The results demonstrated that both strains exhibited robust growth in rye bran sourdough. Compared to the blank control rye bran–wheat flour dough (RB dough), sourdough incorporation enhanced percentages of β-sheet and α-helix secondary structures, facilitating the formation of a more ordered gluten network structure. This contributed to reduced bread baking loss and decreased bread hardness, gumminess, and chewiness, with Lpb. plantarum G8 exhibiting the most pronounced effects. Notably, G8 bread displayed superior antifungal efficacy, extending shelf life by 8 d (mold appearance at room temperature: 12 d for G8 vs. 4 d for RB). Furthermore, G8 bread exhibited significantly increased diversity and content of volatile compounds, and received higher preference scores from the sensory panel. This study further advances the development of mold-resistant bakery products. Full article

This study investigates the effect of extended rye scald fermentation times (12–48 h) on its biochemical properties and rye bread’s nutritional and sensory qualities. Traditional rye bread production in Latvia involves prolonged fermentation with lactic acid bacteria (LAB), a process that influences the bread’s acidity, sugar content, and concentrations of organic acids, fructans, and phytates. Scald fermentation was analyzed at intervals of 0, 12, 24, 36, and 48 h to monitor microbial activity, particularly LAB population dynamics. Organic acids and sugar profiles were analyzed using HPLC, while phytic acid and fructan concentrations were determined using the Phytic Acid Assay Kit (K-PHYT) and Fructan Assay Kit (K-FRUC). Sensory evaluation assessed attributes including aroma, sour and sweet taste, stickiness, and floury aftertaste. A rapid pH decrease and increased total titratable acidity (TTA) after 12 h confirmed scald’s suitability as a substrate for Lactobacillus delbrueckii metabolism. Lactic acid content increased 13.8-fold after 48 h. Combined scald and dough sourdough fermentation reduced phytic acid by 20% and fructans by 49%, improving mineral bioavailability. Extending fermentation beyond 24 h showed no significant differences in physicochemical parameters, although it improved sensory quality, reduced stickiness, balanced sweet–sour flavors, enhanced aroma, and minimized floury aftertaste. Full article

This study aimed at producing a sourdough bread supplemented with two marine algae powders of Ulva lactuca and Gelidium corneum at 2.5, 5, 7.5, and 10% (w/w, g/100 g DW) at the laboratory scale using mixed starters prepared with three lactic acid bacteria (LAB) combinations (LCS1, LCS2, and LCS3). The phytochemical composition, nutritional value, organoleptic properties, and acceptability of algae bread by consumers were then assessed. Good results were obtained for enriched bread with Gelidium at 2.5% (GB1) with a reducing sugar of 0.77 ± 0.1%, total sugar of 36.90 ± 3.15, and protein content of 8.3 ± 0.2%. While total phenolic content was 8.32 ± 1.20 mg GAE/g DW, total flavonoids was 225.00 ± 11.31 mgQE/g DW, and the antioxidant activity ranged from 71.05 ± 3.71 to 82.93 ± 3.61%. Regarding enriched bread with Ulva at 10% (UB12), reducing sugar was 0.48 ± 0.03%, total sugar was 45.45 ± 5.75%, and protein content was 3.7 ± 0.07%. The total phenolic content value was 6.45 ± 1.19 mg GAE/g DW, total flavonoids was 191.20 ± 12.52 mgQE/g DW, while the antioxidant activity values ranged from 52.06 ± 6.21 to 80.51 ± 1.72%. Microbiological analysis showed that all pathogenic bacteria were not detected in algae bread. The consumer acceptability test revealed that bread enriched at the level of 10% of algae powder was significant for the five selected criteria (general appearance, crumb color, odor, taste, and texture). Traditional bread supplemented with Gelidium powder at 2.5% and Ulva powder at 10%, prepared with combined sourdough (LCS1), showed good antioxidant and nutritional properties and consumer acceptance. Full article

Yeast, bacteria and sourdough are widely used in our daily lives, yet their drying and storage remains a significant challenge. A variety of techniques are used to improve the resistance of cells to thermal, dehydration, oxidative and osmotic stresses, which can occur at different stages of the process. The addition of protective agents prior to drying is a commonly used method, but the mechanisms that may lead to a change in viability following the addition of these agents, or more generally, the interaction between a protective agent and the drying process, are not yet fully understood. This review outlines seven main potential mechanisms, as highlighted in the literature, which can lead to internal or external modifications of the cells. The mechanisms in question are change of membrane fluidity, accumulation of compounds for osmoregulation, prior osmotic dehydration, prevention of oxidation, coating or encapsulation, enhancement in thermal resistance and change in drying kinetics. A comprehensive explanation of these mechanisms is provided. This review also highlights the connection between the mechanisms and the influence of the stresses occurring during drying and storage, which depend on the drying technique used and the operating conditions, the strains and the protective agents involved, on the importance of the different protection mechanisms. By gaining a deeper understanding of the mechanisms of action of protective agents, strategies to improve the quality of the microorganisms obtained after drying can be developed. One such strategy would be to combine several agents to achieve a synergistic effect. Full article