Bread Aroma Research Articles

Effect of sourdough fermented with corn oil and lactic acid bacteria on bread flavor

Corn oil and Lactococcus lactis (L. lactis) were selected for improving the sourdough bread aroma, and their effect on bread flavor was studied. Volatile compounds (VOCs) in sourdough and bread crumbs were determined by gas chromatography−mass spectrometry. The results demonstrated that the VOC profiles appeared mainly dominated by alcohols, aldehydes, ketones, acids, esters, and heterocyclic compounds. Principal component analysis and cluster analysis showed that the formation of most alcohols were promoted by L. lactis, while corn oil addition yielded more aldehydes, ketones, and furans. Further analysis of odor-active components in bread was characterized by aroma extract dilution analysis and odor activity value (OAV). In the sourdough bread obtained with the addition of corn oil and lipase, (E,E)-2,4-decadienal, 2-pentylfuran, 1-octen-3-ol, 3-methylthio-1-propanol, and (E)-2-nonenal had higher flavor dilution factors and OAV, which were the key aroma compounds distinguished from other varieties of breads.

Impact of Soy–Cow's mixed milk enzyme modified cheese on bread aroma

The effect of spray-dried Soy–Cow's mixed milk enzyme modified (SC-EM) cheese on wheat dough properties and bread aroma was evaluated at either 0.1, 0.5, 1.0, 1.5 or 2.0% (w/w). Significant accumulation of amino acids and peptides of dough were noted as SC-EM cheese levels increased. After baking a total of 118 volatile compounds (VCs) were identified in breads having aldehydes, alcohols, esters and acids in major proportions. Higher contents of Maillard product 3-hydroxy-2-butanone, 2-methyl-1-propanol, phenylethyl alcohol, undecane, l-limonene, 2-pentyl furan and lipid oxidation compounds hexanoic acid ethyl ester, octanoic acid ethyl ester, decanoic acid ethyl ester, butanoic acid, hexanoic acid and octanoic acid were observed. Isoamyl alcohol, lactic acid ethyl ester, ethyl sorbate and sorbic acid were the newly identified VCs. These results revealed that SC-EM cheese could be used as improver in dough and contribution to bread aroma. Thus, SC-EM cheese has been proposed to be included in fortified bakery products.

Fiber enrichment of sourdough bread by inulin rich Jerusalem artichoke powder

This study aims to determine the effects of Jerusalem artichoke powder (JAP) utilization on the physical quality and nutritional characteristics of sourdough bread. JAP was applied to both sourdough fermentation medium and bread formulation. The increasing rates of JAP had deteriorated effects on the physical properties (specific volume, color, and texture profile) of bread. JAP decreased significantly in vitro starch digestion rate in sourdough bread. The glycemic index value of 20% JAP-containing sourdough bread was detected to be 75.12. Additionally, total dietary fiber content increased from 2.62 to 5.30/100 g, by JAP incorporation. The total phenolic content and antioxidant activity of control were determined as 43.72 mg GA/100 g and 48.78 µmol TE/100 g, respectively. In comparison, these values were 80.60 mg GA/100 g and 130.77 µmol TE/100 g in samples supplemented with 20% JAP. According to the sensory analysis, utilization of JAP, over 10% resulted in quite low points. Practical applications Inulin is generally used to increase dietary fiber content and decrease the glycemic index of foods. On the other hand, the utilization of foods with inulin-rich JAP not only increases the dietary fiber content but also enriches it with bioactive components and phytochemicals. However, the high addition levels of JAP can deteriorative effects on the sensory features of foods. In this study, due to the specific aroma and sour taste of sourdough bread, JAP was used above the levels stated in the literature without creating a negative effect on the sensory.

Impact of sourdough and transglutaminase on gluten-free buckwheat bread quality

Gluten-free (GF) bread based on starch has low sensory quality and stales faster than conventional wheat bread. At the same time, it is characterized by low nutritional value. Buckwheat flour can be used as an ingredient of GF bread improving favourably its nutritional properties. The application of transglutaminase (TG) that modifies proteins through cross-linking can further improve the overall quality of GF bread. In the present study, we investigated the effectiveness of TG used together with various doses of buckwheat sourdough, prepared using starter cultures L. plantarum ŁOCK 860 and L. brevis ŁOCK 1267, on the quality features of GF buckwheat bread. Compared to control, the exclusive addition of sourdough reduced significantly (p < 0.05) the specific volume of the bread, whereas the crumb was more cohesive and springy with a parallel TG addition. The crumb had lower density, similar to that of conventional bread. The flavor and aroma of the GF buckwheat bread were also improved noticeably. The use of sourdough had a significant effect on the mechanical properties of the crumb. Its structure became more springy. Moreover, the overall sensory quality of experimental bread increased, as the characteristic bitter aftertaste of buckwheat was less noticeable. In conclusion, the simultaneous use of buckwheat sourdough and TG had a positive effect on the total quality score which can lead to the increased sensory acceptability of the GF buckwheat bread.

Effect of Supplementation of Flour with Fruit Fiber on the Volatile Compound Profile in Bread.

This paper presents the analyses of the effect of fiber additives on volatile organic compounds in bread. The bread was baked from wheat flour with the addition of 3% of fruit fiber, following common procedures. After baking, volatile organic compounds contained in the control bread and breads supplemented with cranberry, apple, and chokeberry fiber were determined. The SPME/GC-MS technique was used for the identification of the odor profile, and the electronic nose Agrinose (e-nose) was used to assess the intensity of the aroma. The results of the analyses revealed the profile of volatile organic compounds in each experimental variant, which was correlated with responses of the electronic nose. The results indicate that the volatile compound profile depends on the bread additives used and influences the intensity of bread aroma. Moreover, the profile of volatile organic compounds in terms of their amount and type, as well as the intensity of their interaction with the active surface of the electrochemical sensors, was specific exclusively for the additive in each case.

Volatile Organic Compounds in Breads Prepared with Different Sourdoughs

Sourdough is an old example of a natural starter composed of a mixture of flour, water, and metabolites and is produced by naturally occurring lactic acid bacteria and yeasts that influence bread aroma. In this work, four types of sourdough were used to prepare bread: one sourdough with yeast beer and three with bacteria and yeasts. The physicochemical parameters (pH, moisture, water activity, and organic acids) of the bread and sourdoughs were assessed. Lactic, acetic, and succinic acids were found in considerable amounts in sourdoughs and the corresponding breads. The fermentation quotient (molar ratio between lactic and acetic acid) ranged from 0.39 to 3.4 in sourdoughs. Lactic acid was prevalent in all types of bread and showed the highest value in bread made from sourdough with a 1.5 bacteria/yeast ratio (8722.24 mg/kg). Moreover, volatile organic compounds were identified in bread samples. Alcohols, aldehydes, and acetic acid were mainly found. The alcohol concentration ranged from 140.88 to 401.20 ng/g. Aldehydes ranged from 185.01 to 454.95 ng/g, and acetic acid ranged from 91.40 to 173.81 ng/g. Bread prepared from sourdough with a 1.5 bacteria/yeast ratio showed a considerable amount of alcohols and acetic acid.

Evaluating the Aroma of Fermented Liquid-containing Bread Based on Colours

Evaluating the Aroma of Fermented Liquid-containing Bread Based on Colours

Nutritional and technological assessment of durum wheat-faba bean enriched flours, and sensory quality of developed composite bread.

Faba beans are acknowledged as a good source of proteins, minerals, fibers, vitamins and antioxidants. A blending study was undertaken in order to prepare naturally bread from enriched flours with added nutritional value, mainly in terms of Iron and proteins. Enriched flours were prepared with varied levels (25, 30, 35 and 40%) of whole faba bean flour to assess the effects of this substitution on their nutritional and technological properties. Then, whole durum wheat bread (regular) and enriched bread at 40% substitution level (composite bread) were prepared and subjected to sensory evaluation. The substitution level of composite bread was selected on the basis of Iron and proteins contents and technological results of the flour blends. Nutritionally, except for moisture, fibers, fat, zinc and sodium values, significant (p < 0.05) increases were showed in ash, proteins, minerals, total phenolic compounds, condensed tannins, total flavonoids and anti-radical activity values. Technologically, significant (p < 0.05) decreases were recorded for lightness and whiteness index. The gluten strength value revealed a significant (p < 0.05) decrease as whole faba bean flour was added. On the sensory level, the level of substitution (40%) chosen for the manufacture of composite bread resulted in acceptable bread by consumers. Moreover, composite bread was most preferred in aroma as it imparts a feeling of satiety. The observed nutritional improvements could be useful for malnourished people, including those having Iron and proteins deficiencies. Technologically, the observed changes didn’t present limitations since composite bread was accepted by consumers even at 40% substitution level. Besides, the slight preference of composite bread aroma might encourage its consumption by consumers. Also, its promotion of satiety is important for gluten sensitivity sufferers. Our results suggested that 40% is the appropriate ratio to increase, at the same time, Iron and proteins contents of enriched flours as well as their overall nutritional quality. Also it was possible to produce natural composite bread at this level (40%) while maintaining adequate technological and sensory quality.

Improving bread aroma using low-temperature sourdough fermentation

To improve the aroma of bread, two aroma-producing yeast isolates from the Chinese liquor starter culture called Daqu, Meyerozyma guilliermondii CGMCC 17606 and Pichia kudriavzevii CGMCC 17607, were combined with Lactobacillus sanfranciscensis DSM20451T, were used for sourdough fermentation at 10, 20, and 30 °C. Volatile aroma compounds in bread crumb were extracted using headspace solid-phase micro-extraction and analyzed using gas chromatography-mass spectrometry and gas chromatography-olfactometry-mass spectrometry. The quality of the final bread was analyzed using sensory evaluation. Addition of sourdough fermented with mixed starters at 10 °C promoted bread aroma, showed increased sensorial qualities, and was preferred by panelists. Acetic acid, 1-octen-3-one, and dimethyl trisulfide, were the most aroma-active compounds in sourdough bread fermented with M. guilliermondii and L. sanfranciscensis, whereas those in sourdough bread fermented with P. kudriavzevii and L. sanfranciscensis were acetic acid, 1-octen-3-one, 2-methoxy-4-vinylphenol, 3-methylthio-propanal, furfural, and 1-(2-furanyl)-ethanone. Reducing the fermentation temperature to 10 °C increased the formation of these key volatiles, as well as other aroma-active compounds, such as 3-methyl-1-butanol, 3-methylbutanal, 2-methyl-1-propanol, 1-octen-3-ol, isogeraniol, benzaldehyde, benzene acetaldehyde, ethyl octanoate, ethyl decanoate, phenylethyl acetate, furfural, and 2-pentylfurane. The amount of furans, pyrazines, and volatiles converted from amino acids in bread crumb also increased with the protein hydrolyzation and amino acid formation in sourdough fermented at 10 °C.

Large-scale identification and characterization of phenolic compounds and their marker–trait association in wheat

Phenolic compounds (PCs) are important biomolecules as they affect processing (color, aroma, and taste quality of bread, and grain hardness) and nutrition quality (antioxidant and other health benefits). This study identified a set of 115 PCs by screening 100 Indian bread wheat varieties that showed wide variation in PCs content. These PCs were classified into 29 phenolic acid and their derivative, 71 flavonoids, 2 chalcones, 8 stilbenoids 1 theaflavin, 1 eugenol, and 3 coumarins. Of the 115, standards for 25 PCs were validated by matching their RT (retention time), MS and MS/MS fragmentation pattern on UPLC-QTOF-MS/MS. The range of PC content was from 0.01 µg/100 g for luteolin in ‘GW 503’ to 547.63 µg/100 g for vanillin in ‘Durgapur 65.’ The marker–trait association analysis identified 81 SSR markers which were associated with twelve PCs. Of 81, 53 were significantly associated on 5% FDR at true value (p < q). After multiple test correction (adjusted p value and 5% FDR), eight SSR markers were significantly associated with five PCs, namely ‘rutin,’ ‘hesperidin,’ ‘2,4-dihydroxybenzoic acid,’ ‘vanillin,’ and ‘salicylic acid.’ A substantial number of markers showed coefficient of variation (R2) ranged from ~ 5 to 45% for these PCs. The variations present in the set of wheat varieties and linked markers can be exploited for the improvement of PCs affecting processing and nutrition quality of wheat through molecular breeding and functional genomics tools.

Comparison of two rapid descriptive sensory techniques for profiling and screening of drivers of liking of sorghum breads

Rapid descriptive methods have emerged as a relatively simple alternative for screening the sensory attributes of products that drive their liking, and may contribute to identify sorghum genotypes with potential for development of gluten-free breads with higher consumer acceptance. Two rapid techniques, Check-All-That-Apply (CATA) and Optimized Descriptive Profile (ODP), were herein compared on their ability to describe, discriminate and identify the drivers of liking of sorghum breads. Gluten-free bread formulations were developed using flours from selected sorghum genotypes (CMSS005, BR 501, BRS 332, BRS 330, BRS 305 and 1167048), besides commercial sorghum and rice flours. A semi-trained panel (n = 18) evaluated the samples using the ODP method, whereas consumers (n = 124) completed the CATA questionnaire and rated the liking in a 9-point hedonic scale. A total of 24 and 11 sensory descriptors were perceived by assessors as different among samples for CATA and ODP, respectively, with color and appearance-related attributes critical to discriminate samples in CATA, whereas flavor and texture descriptors had also prominent contribution in ODP. A similar pattern of sample distribution was noticed for both methods, which were shown to be highly and positively correlated (RV = 0.92, p < 0.002). Genotypes influenced the consumer perception of sorghum breads, being the BRS 332 and the CMSS005 breads among the most and the least accepted samples for either consumer segment, respectively. While 10 drivers of liking were identified by CATA, including ‘appearance of whole flour breads’, ‘uniform alveoli’, ‘neutral flavor’ and ‘soft aroma’, in ODP ‘crumb color’, ‘crust color’, ‘spots’ and ‘traditional bread aroma’ drove bread acceptance. In summary, both methods were successfully applied and provided similar pattern of sample discrimination, whereas the attributes used for sample characterization, as well as those identified as drivers of liking were generally different. The ODP offers a simpler option for a quantitative perspective, while CATA remains as an easy method considering qualitative aspects, being clearly faster than ODP.

Aroma and quality of breads baked from old and modern wheat varieties and their prediction from genomic and flour-based metabolite profiles.

Bread aroma is the principal characteristic perceived by the consumer yet it is mostly disregarded in the product chain. The main aim of this study was to evaluate the potential to include bread aroma as a new target criterion into the wheat product chain. The objectives of our study were to (i) quantify the influence of genetic versus environmental factors on the bread aroma and quality characteristics, (ii) evaluate whether bread baked from modern wheat varieties differ in terms of aroma from those baked from old varieties, and (iii) compare genomic and metabolomic approaches for their efficiency to predict bread aroma and quality characteristics in a wheat breeding program. Agronomic characters as well as bread aroma and quality traits were assessed for 18 old and 22 modern winter wheat varieties evaluated at up to three locations in Germany. Metabolite profiles of all 120 flour samples were collected using a 7200 GC-QTOF. Considerable differences in the adjusted entry means for all examined bread aroma and quality characters were observed. For aroma, which was rated on a scale from 1 to 9, the adjusted entry means varied for the 40 wheat varieties between 3 and 8. In contrast, the aroma of bread prepared from old and modern wheat varieties did not differ significantly (P<0.05). Bread aroma was not significantly (P<0.05) correlated with grain yield, which suggested that it is possible to select for the former character in wheat breeding programs without reducing the gain of selection for the latter. Finally, we have shown that bread aroma can be better predicted using a combination of metabolite and SNP genotyping profiles instead of the SNP genotyping profile only. In conclusion, we have illustrated possibilities to increase the quality of wheat for consumers in the product chain.

Quantitative Analyses of Key Odorants and Their Precursors Reveal Differences in the Aroma of Gluten-Free Rice Bread and Wheat Bread.

Rice flour is one of the most important raw materials in gluten-free products. However, the aroma of gluten-free rice bread is less accepted by consumers than that of commercial wheat bread. Therefore, 18 selected aroma compounds were determined in rice and wheat breads by stable isotope dilution assays (SIDA) to elucidate differences in the sensory characteristics, concentrations, and odor activity values (OAVs). The OAVs of most aroma compounds varied greatly between a rice and a wheat bread. In particular, 2-aminoacetophenone with a grape-like, medicinal aroma was characteristic for rice bread crumb and crust, while maltol was only relevant in wheat bread crust. Ehrlich pathway products varied in their concentration between the bread crumbs and were correlated with the contents of their corresponding free amino acid precursors in the flours and doughs. The analysis of rice flour revealed that only a few aroma compounds were retained in the bread. Consequently, the bread making process has a high relevance in aroma compound formation. In a comparison of breads prepared from fresh and stored rice flour, hexanal was identified as an important indicator for aging in rice bread and flour.

Defined co-cultures of yeast and bacteria modify the aroma, crumb and sensory properties of bread.

Yeast and bacterial communities inhabit a sourdough starter to make artisanal bread. This study shows whether the interactions of micro-organisms derived from Australian sourdough starters provide some of the positive flavour, and aroma properties to bread by using defined sourdough cultures as the sole leaven in bread production. An investigation of Australian sourdough starters found that they contained Saccharomyces cerevisiae and Kazachstania exigua yeasts. When these yeasts were inoculated alone to ferment wheat flour in an extended fermentation, the bread had a heterogeneous crumb structure, a deeper colour and a distinctive chemical aroma profile than those made with commercial baker's yeast. When bread was made combining these yeasts individually and in combinations with lactic acid bacteria also isolated from these sourdough starters, including Lactobacillus plantarum, L. brevis, L. rossiae, L. casei, the bread aroma profiles and crumb structure were more distinctive, with compounds associated with sour aromas produced, and preferred by sensory panels. The use of defined mixed cultures as the leaven in bread making, by exploiting the microbial diversity of artisanal Australian starters, can produce bread with distinctive and attractive aromas. Understanding and identifying the community ecosystems found in sourdough cultures and using them as the sole leaven in bread production provide novel insights into microbial interactions and how they affect food quality by removing the effects of commercial yeast strains.

Selection of the most suitable mixture of flours and starches for the improvement of gluten-free breads through their volatile profiles

Gluten-free breads have been characterised by a weak aroma. In this study, different mixtures of gluten-free flours (teff and quinoa) and starches (wheat and corn) were investigated by SPME-GC/QTOF with the aim of providing flours that potentially improve the aroma of gluten-free bread. Bread with the highest proportion of corn starch (60%) was discarded for its higher content in rancid volatile compounds from lipid oxidation, while bread with the highest level of wheat starch (60%) was discarded for its lower content of the key aroma 2-acetyl-1-pyrroline. Thus, the bread composed of 40% of each starch, 15% of quinoa flour and 5% of teff flour was chosen due to the higher proportion of pleasant volatiles from fermentation, 2-acetyl-1-pyrroline and pyrazines as well as the lower levels in rancid volatile compounds from lipid oxidation. Moreover, it exhibited relatively dark crust, high volume and superior textural properties.

Active EVOH/PE bag for sliced pan loaf based on garlic as antifungal agent and bread aroma as aroma corrector

The aim of this work was the industrial development of an antifungal film containing garlic extract and bread aroma to be applied as active packaging for preservative-free sliced pan loaf. The material consisted of LDPE coated with ethylene vinyl alcohol copolymer. First the coating formulation was optimized to be suitable for flexographic equipment. A 1 μm coating of EVOH containing the agents was applied onto the LDPE film. Garlic extract release provides the antimicrobial capacity while bread aroma masks the inappropriate garlic aroma. The optimized formulation contained 8% of garlic extract and 8% of bread aroma. Bags were prepared and used to pack sliced pan loaves. Mould development was delayed from 6 to 12 days by use of the active bag. Sensory and textural characterization of the food also revealed that the bread maintained its characteristics, and sensory panellists considered the product acceptable and with good purchase intention.

Development and optimization of antifungal packaging for sliced pan loaf based on garlic as active agent and bread aroma as aroma corrector

The aim of the present work was the development of antimicrobial films containing garlic extract to be applied as active packaging for preservative-free sliced pan loaf, with the goal of extending its shelf-life. First, the antimicrobial capacity of garlic extract, a compound used as active agent, was tested against Penicillium expansum by the disc diffusion method. The extract showed high antimicrobial activity, 0.1 μL per Petri dish being the minimum inhibitory amount, and 0.25 μL the minimum fungicidal amount. Bread aroma was also used to mask the pungent odour of garlic and it was confirmed to have no antimicrobial activity. Subsequently, polyethylene (PE) aqueous emulsion and ethylene-vinyl alcohol copolymer (EVOH) and zein hydroalcoholic solutions containing 0.25 and 0.5% (w/w per dry polymer) of garlic extract and bread aroma were used to coat PE films, producing PE/PE, PE/EVOH and PE/zein active films. The antimicrobial capacity of the films was studied in vitro against Penicillium expansum, and in vivo with natural sliced bread. The results showed that all the films presented some antimicrobial activity, PE film coated with zein containing 0.5% of garlic extract and bread aroma being the film presenting the best results, maintaining bread free of mould infection for 30 days. Sensory tests showed that the addition of 1% of bread aroma improved the sensory experience of consumers and also revealed good purchase intention.

Analytical feasibility of a solvent-assisted flavour evaporation method for aroma analyses in bread crumb.

The analysis of bread aroma is essential in order to evaluate its quality as well as to improve it. The use of different methodologies for the analysis of volatile compounds lead to varying results. In the present study, the matrix effect, extraction efficiency, limits of detection and quantification as well as the precision of a proposed solvent-assisted flavour evaporation methodology were evaluated for the first time and compared with a reference method, both differing in the distillation step. The repeatability (<8%) and matrix effect (present in 15 of the 31 compounds) were improved with the proposed method but the extraction efficiencies (average of 52%) and the intermediate precision (>15%) were not as required. However, the applicability of the reference method was limited to breads with fat levels <2%. For breads higher in fat, the proposed method represents an alternative for aroma analysis.

Aroma effects on food choice task behavior and brain responses to bakery food product cues

Bread, and especially whole grain bread is an important source of dietary fibers. It was tested with behavioral and fMRI measures whether bread becomes more attractive when it is presented with bread aroma.Twenty-eight healthy normal-weight women were exposed to images of bakery products (brown bread, white bread and cookies) without aroma or with a congruent (bread aroma) or non-congruent (“warm wood”) aroma.In general, product effects were larger than aroma effects. Images of brown bread were preferred over images of white bread as shown by direct comparisons, choice reaction times, as well as liking and wanting scores. Aroma had no effect on liking and wanting, but did affect food choice task behavior, where images of brown bread were preferred more often in the presence of warm wood aroma and images of cookies were preferred more often in the presence of bread aroma. The fMRI data suggest that bread aroma may increase the salience of bakery products compared to no aroma and a non-food aroma. Specifically, bread aroma induced greater activation for cookies in areas related to reward anticipation. The correlations between behavioral measures and brain responses suggest lower attention for and a habitual response to brown bread and higher attention and a more goal-directed response to white bread.In conclusion, aroma can affect choice task behavior for brown and white bread albeit in an incongruent manner. The more habitual response to brown compared with white bread suggested by the neural data underscores that nudging towards brown bread consumption with (bread) aroma will probably not be effective.

Investigation of the effect of multicomponent acidulants on the preservation of freshness and aroma of rye-wheat bread

Для производства ржано-пшеничного хлеба на мини предприятиях и в заведениях ресторанного хозяйства предложена ускоренная технология его приготовления путем применения подкислителей. Разработаны поликомпонентные подкислители «Оптимальный 1» и «Оптимальный 2». Их оптимальная дозировка, 2 % к массе муки, способствует сокращению технологического процесса в 2,5…3 раза и обеспечивает сохранение свежести готовых изделий