Bread Flavor Research Articles

참죽 분말을 첨가한 식빵의 품질 특성 및 항산화 활성

Cedrela sinensis is a Korean traditional wild herb found especially in the southern provinces of Korea. This study investigated the effects of Cedrela sinensis powder on the antioxidant activities and quality characteristics of bread. Bread was prepared with different amounts of Cedrela sinensis powder (at ratios of 0, 1, 2, and 3% of total flour quantity). The results showed that the dough pH, moisture, and fermentation tension levels decreased as Cedrela sinensis powder content increased. Bread volume and specific volume decreased (p<0.01) with an increasing amount of Cedrela sinensis powder (Bread weight increased (p<0.001)). As Cedrela sinensis powder content increased, color 'a' value decreased, and 'b' value increased. Sensory parameters such as color (p<0.01), flavor (p<0.01), appearance (p<0.001), taste, softness (p<0.05), and overall quality (p<0.01) of bread containing 2% Cedrela sinensis powder were measured. Total phenol contents and DPPH free radical scavenging activity of bread significantly increased with increasing Cedrela sinensis powder content (p<0.001). Based on these results, we suggest that Cedrela sinensis can be used for increasing the consumer acceptability and functionality of bread.

Salt and Bread: Latvia’S Experience

Abstract Much research has shown that reduction in salt intake can have a very positive impact on human health, as salt intake plays a critical role in regulating blood pressure. According to the World Health Organization, populations with low salt intake, all other factors being equal, usually have lower blood pressure level, in that way decreasing the risk of cardiovascular disease. The main source of salt in the diet is ready-made food, and only about 11% of overall salt intake is the salt people add to their food themselves. A common EU framework for salt reduction has been developed, which describes a common vision for a general European approach towards salt reduction. Bread has been identified as an important contributor to the daily salt intake in many countries. On the other hand, salt has important technological functions in bakery products. It improves the qualities of dough, fermentation, and flavour of bread. The aim of this paper was to evaluate the amount of salt in Latvian bread and to assess the need for decreasing the amount of salt in bread. The majority of Latvian bread contains 1.1 to 1.2% salt in flour, but in some other kinds of bread it is even less.

Physicochemical and sensory properties of soy bread made with germinated, steamed, and roasted soy flour

For the development of healthful gluten-free soy bread acceptable to consumers, we evaluated the effects of various processing procedures for soy flour on bread quality, in terms of beany flavour and texture. We pretreated soy flour by both non-heating (raw:NS and germinated:GS) and heating (steamed:SS and roasted:RS) methods. In addition, to improve the loaf volume, we added 1% hydroxypropyl-methylcellulose (HPMC) to RS flour. Lipoxygenase activity was retained in the non-heat-treated flours (279U/g for NS and 255U/g for GS), but was significantly reduced in the heat-treated flours (106U/g for SS and 69U/g for RS). Moreover, heat-treated flour had higher isoflavone and ferric reducing antioxidant power than had non-heat-treated flour. However, RS flour had the lowest moisture content and lowest L∗ value. The GS bread had the highest specific loaf volume (3.53cm3/g), followed by NS (2.96cm3/g), RS (2.25cm3/g), and SS (1.81cm3/g) bread. GS bread had the lowest hardness (1.53N), followed by NS (1.65N), RS (2.00N), and SS (3.75N) bread. The addition of 1% HPMC to RS increased the loaf volume (2.44cm3/g), but decreased the bread’s hardness (1.80N). As to the sensory properties, the bread with heat-treated flour was perceived to have a less beany odour and taste than was the bread with non-heat-treated flour. However, the latter had a better appearance than the former. These results indicated that soy flour pretreatment could enhance the loaf volume and reduce the beany flavour of whole soy bread.

A STUDY ON THE IMPACT OF CHEMICAL PRESERVATIVES ON SENSORIAL EXCELLENCE OF BREAD AT VARIOUS TEMPERATURES

A critical study was ca rried out to evaluate the impact of chemical preservatives on the sensorial excellence of bread at various temperatures. The entire experiment was undertaken in the Institute of Food Sciences and Technology, Sindh Agriculture University, Tandojam in 2011. Two types of preservatives i.e. calcium propionate (CP) and calcium lactate (CL) at 14 0 C, 22 0 C and ambient temperature (32 0 C) were investigated. The results revealed that both the preservatives at a level of 0.4 and 0.8g at all temperatures were signifi cantly (P<0.01) effect the appearance, flavor, palatability and texture of bread however; the results were non - significant in case of color of the bread. Among the temperatures, 14

Sourdough Technology-A Traditional Way for Wholesome Foods: A Review

Abstract: In the present era, consumers wish to have a wide range of foods that are nutritious and flavorful and have long shelf life without added preservatives. Sourdough is an important modern fermentation of cereal flours and water based upon an earlier spontaneous process. The sourdough microflora is dominated by lactic acid bacteria and, along with yeast, they play a key role in the fermentation of bread dough. Factors that affect the quality of sourdough are dough yield, temperature, type of starter culture, acidity of the medium, and the substrate. Sourdough is classified into 3 types (Types I, II, and III); the most widely used for commercial production is Type III. The sourdough fermentation has a number of beneficial effects that include prolonged shelf life, accelerated volume gain, delayed staling, improved bread flavor, and good nutritional value. Sourdough also improves sensory characteristics such as loaf volume, evenness of baking, color, aroma, taste, and texture of breads. Sourdough has been reported to contribute to extended shelf life by inhibiting spoilage bacteria and mold growth.

Risk factors for the occurrence of undifferentiated carcinoma of nasopharyngeal type: A case-control study

The incidence rate of nasopharyngeal carcinoma in Serbia is less than one per 100,000 citizens, which classifies it as a region with low incidence for this disease. The aim of this study was to test some hypotheses of the risk factors for undifferentiated carcinoma of nasopharyngeal type (UCNT) in the low incidence population. A case-control study was used for the research. The study included 45 cases with histopathological diagnosis of UCNT and 90 controls. Cases and the controls were individually matched by sex, age (+/- 3 years), and place of residence (city-village). Data were gathered about sociodemographic characteristics, occupational exposure to harmful agents, habits, diet, personal history, and family history. In the analysis of the data, conditional univariate and multivariate logistic regression analyses were applied. According to the results of multivariate logistic regression analysis UCNT was significantly positively associated with "passive smoking" of tobacco in the family during childhood, frequent consumption of industrially manufactured food additives for enhancing flavour and frequent consumption of white bread. UCNT was significantly negatively associated with frequent consumption of margarine, olive oil and cornbread. In our low incidence population, an independent risk factor for the occurrence of UCNT was "passive smoking" of tobacco in the family during childhood, use of industrially manufactured food with additives for enhancing flavour and consumption of white bread. Multicentric study enrolling a greater number of cases would be desirable.

Advances in the Understanding of the Chemical Reactions Responsible for Bread Flavour Quality

This work aimed at analysing bread extracts obtained under headspace and artificial mouth conditions in order to study the reactions responsible for bread flavour quality. Selected extraction conditions were first compared according to the odour and aroma representativeness of the bread extracts. The optimal conditions were then applied to extract volatiles of a conventional gluten bread formulation and an innovative gluten-free bread formulation. Results reveal that an extraction duration of 10 min in the artificial mouth was sufficient to obtain a representative aroma extract. Yet, 30 min of headspace extraction were necessary to obtain a representative odorant extract. The comparison between these both extracts shows that significantly higher quantities of bread compounds were extracted with artificial mouth. This innovative device could thus be used to better understand the mechanisms involved in the formation of those volatiles that are responsible for the perceived bread odour and aroma.

Characterisation of fresh bread flavour: Relationships between sensory characteristics and volatile composition

Abstract The sensory properties and volatile composition of bread flavour were measured to allow improved understanding of perceived bread freshness. Twenty bread varieties consisting of specialty breads ( n = 10) and commercial breads ( n = 10) were evaluated by descriptive sensory analysis, and volatile composition of all breads was measured by proton transfer reaction mass spectrometry (PTR-MS). The specialty breads ( n = 10) studied had been evaluated by consumers, and perceived freshness was known. All sensory attributes and 33 mass ions representative of the PTR-MS spectra significantly ( p

The Effects of Mixing Stage and Fermentation Time on the Quantity of Flavor Compounds and Sensory Intensity of Flavor in White Bread

Flavor compounds in white bread have been analyzed by a static-headspace-type GC/MS and sensory evaluation for clarifying the effects of mixing stage and fermentation time on the intensity of flavor compounds as assessed in the crumb and sensory scores of flavor in white bread. Principal component analysis (PCA) and analysis of variance (ANOVA) were applied to the peak area of total ion chromatogram as well as sensory scores of 8 sensory descriptors for flavor intensity. Although the results of instrumental analyses showed the superiority of fermentation time over mixing energy as the governing factor of white bread flavor, the results of statistical analyses for the scores of sensory evaluation showed the superiority of mixing energy over fermentation time. The difference in the governing factor was probably due to overestimation for the effect of alcohols on the flavor quality of white bread, especially ethanol derived from the fermentation process.

Lactobacillus reuteri CRL 1100 as starter culture for wheat dough fermentation

The effect of sucrose on the fermentation balance of Lactobacillus reuteri CRL 1100 and the invertase activity of this strain in wheat dough and culture medium (MRSs) was evaluated. The enzyme activity was dependent on the environmental pH releasing glucose and fructose from sucrose hydrolysis. Glucose was used as carbon source, while fructose was mainly used as electron acceptor to produce mannitol up to 10 h of fermentation. Thereafter, fructose seemed to be metabolized by the heterofermentative pathway, which determined an increase in the concentration of acetate (6 mmol l −1), lactate (2 mmol l −1) and ethanol (1 mmol l −1) and the lack of mannitol formation after glucose depletion. The fermentation balance of Lb. reuteri CRL 1100 during the dough fermentation resulted in lower (63%) ethanol, higher (75%) acetate production and soluble carbohydrates concentrations, like MRSs cultures. This fermentation profile would be important to obtain an optimal growth of yeast and the optimal bread flavor and taste.

Evolution of aroma volatiles during storage of sourdough breads made by mixed cultures of Kluyveromyces marxianus and Lactobacillus delbrueckii ssp. bulgaricus or Lactobacillus helveticus

Two mixed starter cultures were used for sourdough bread making to evaluate their ability to improve quality and increase bread shelf-life: Lactobacillus delbrueckii ssp. bulgaricus or Lactobacillus helveticus mixed with the lactose fermenting yeast Kluyveromyces marxianus as alternative baker’s yeast. Control sourdough breads ( K. marxianus) without the addition of bacteria, were also prepared. The changes on the headspace aroma volatiles during storage were assessed using solid-phase microextraction (SPME) GC–MS analysis. The effect of these changes on bread flavour was evaluated by consumer preference evaluations and the results were co-evaluated with those from the GC–MS analysis. The obtained results showed differences in the volatile composition of the different types of breads examined, as well as dramatic decreases of the number and the amount of volatiles after five days of storage. The sourdough breads made with K. marxianus and L. bulgaricus, had a more complex aroma profile, longer shelf-life and achieved the highest scores in the sensory tests.

Effect of Sweet Potato Leaf and Stem Addition on Dough Properties and Bread Quality

Sweet potato leaf and stem, rich in dietary fibre, were used to study their effects on properties of dough and toast bread. Dried and pulverised leaf and stem were separately added at 5, 10 and 15% substitution level. Rheological properties, color and texture of the bread were measured by a farinograph, colorimeter and texture profile analyser, respectively. Results showed water absorption and maximum tolerance index of the dough increased with increasing amount of leaf and stem, while development time, stability and time to breakdown decreased. Bread crumb with substituted leaf was darker than that with substituted stem, and both were significantly darker than the control. Texture analysis indicated little changes in adhesiveness, but hardness and chewiness of bread at the substitution level above 5% were significantly higher than those of the control. Sensory evaluation showed a tendency that the taste, texture, colour, flavour and overall acceptability of bread substituted with 5% stem were better than those with 5% leaf, and comparable to those of the control.

Tracking Generated Bread Flavor in Bread-making Process by Using an Odor Intensity Indicator (OII) and Fixation of Bread Flavor in Oil

Three groups of bread flavor such as bread flavor I (alcohol odor), bread flavor II (bread odor), and bread flavor III (baked odor) are successively generated from dough in the breadmaking process. We could observe these flavors and intensities by sensory test, and measured the amounts of each flavor by the Odor Intensity Indicator (O I I). When oven-temperature was increased from 190 to 230 °C, the general profiles of appearance of bread flavors were changed to earlier time in the breadmaking process, and the amount of bread flavor II was gradually decreased. When bread dough was increased from 25 to 75g, the amount of total bread flavors and the bread flavor II increased quantitatively. Increase of the amount of yeast from 8.7 to 17.4 g per 515 g dough did not affect the amount of the bread flavor II. When sugar was increased from zero to 14.5 and 29.0 g per 515 g dough, the amount of bread flavor II was unchanged and decreased, respectively. When salt was increased from zero to 2.9 and 5.8 g per 515 g dough, the amounts of bread flavors were successively increased, but the bread flavor II only increased with 2.9 g salt-dough. Bread flavor II could be fixed in liquid oil under these optimum breadmaking conditions.

Glutamine deamidation by cereal-associated lactic acid bacteria

It was the aim of our work to investigate glutamine deamidation by lactic acid bacteria isolated from cereal fermentations and to elucidate the ecological and technological relevance in baking of the conversion of glutamine to glutamate. Lactobacillus sanfranciscensis and Lact. reuteri were found to display glutaminase activity. The addition of glutamine to modified Man, Rogosa and Sharp medium increased the cell yields of Lact. sanfranciscensis, as well as the production of lactic and acetic acid. The final pH; however, was increased in the glutamine-containing medium. The addition of 47 mmol kg(-1) glutamate to chemically acidified doughs significantly changed the bread flavour. In sourdoughs with enhanced proteolytic activity, strain-dependent production of 27-120 mmol glutamate per kilogram sourdough was observed. Lactobacillus sanfranciscensis and Lact. reuteri converted glutamine into glutamate; this conversion improves the acid tolerance of lactobacilli and significantly influences wheat bread flavour. This paper illustrates the complex interaction of sourdough-lactobacilli with their environment: the flour provides substrates for metabolic activities that enable the lactobacilli to reach higher cell counts, and the produced metabolite may be one of the reasons why the flavour of fermented breads is different to the flavour of chemically acidified breads.

Carbohydrate, peptide and lipid metabolism of lactic acid bacteria in sourdough

The metabolic pathways of lactic acid bacteria that influence bread quality are coupled to the central carbon flux by the availability of cofactors influencing the cellular and environmental redox potential. Homo- and heterofermentative metabolism differ fundamentally with respect to the requirement for regeneration of reduced cofactors, NADH or NADPH. The utilization of co-substrates such as oxygen or fructose as electron acceptors by obligate heterofermentative lactobacilli is coupled to an increased production of acetate in dough. Recently, several oxidoreductases involved in cofactor regeneration were characterized and glutathione and short-chain aldehydes derived from lipid oxidation were identified as substrates for cofactor regeneration by Lactobacillus sanfranciscensis. Based on the different metabolic requirements for cofactor regeneration, homo- and heterofermentative lactobacilli exert divergent effects on redox-reactions in sourdough that influence bread quality beyond the formation of acetate. Proteolysis, followed by peptide or amino acid metabolism by LAB is one of the key routes of flavour formation in bread flavour, and enables the strain-specific formation of antifungal metabolites. Peptide metabolism as well as the metabolism of cysteine, arginine, and phenylalanine in Lactobacillus plantarum, L. sanfranciscensis, and Lactobacillus pontis is increasingly understood and these insights provide new opportunities for the directed application of sourdough LAB for improved bread quality.

매실 리큐르 제조 부산물인 매실 과육을 첨가한 식빵의 품질 특성

매실리큐르 제조 후 생성되는 매실 부산물을 10%, 20% 농도로 식빵 제조시 첨가하여 대조구와 품질특성을 비교하였다. 반죽과 식빵의 pH는 매실 첨가량이 증가할수록 감소하였으며, 산도는 증가하였다. 반죽의 발효팽창력과 굽기손실율은 매실 첨가량이 증가할수록 감소하였다. 매실 과육을 첨가한 식빵은 첨가량이 증가할수록 무게는 증가하였으나 부피는 감소하였다. 매실 과육 10% 첨가한 반죽의 L값은 대조구와 유사하였고, 20% 첨가구는 유의적으로 감소하였다. a값은 감소하였으며, b값은 유의적으로 증가하였다. 빵표면의 L값은 매실 첨가구가 대조구보다 증가하였으며 적색도(a)는 감소하였다. b값은 매실 첨가에 따른 유의적인 변화는 관찰할 수 없었다. 빵 내부의 색도는 매실 첨가량이 증가할수록 L값과 a값은 감소하고 b값은 증가하는 경향을 나타내었다. 식빵의 조직감은 10% 첨가구의 hardness와 strength는 대조구에 비해 감소하였으나 20% 첨가구는 증가하였다. Cohesiveness와 springiness 대조구에 비해 증가하였으나 첨가농도에 따른 뚜렷한 차이는 관찰할 수 없었다. 식빵의 관능검사 결과 맛과 풍미는 매실 과육 10% 첨가구의 기호성이 대조구에 비해 유의적으로 증가하였으나, 그 외 색택, 씹힘성, 빵의 부드러운 정도(softness) 그리고 종합적 기호도의 유의적 차이는 인정되지 않았다. 매실 과육 20% 첨가한 식빵은 대조구에 비해 기호성이 유의적으로 감소하였다.

Relationships Between Sensory Flavor Evaluation and Volatile and Nonvolatile Compounds in Commercial Wheat Bread Type Baguette

ABSTRACT: A sensorial evaluation was carried out on the flavor of wheat bread using a test of consumer acceptance for this type of product. The 5 samples evaluated corresponded to prebaked baguettes from the main brands marketed in Spain. At the same time, headspace analysis using a solid‐phase microextraction (SPME) method was used to assess the volatile components of the bread crumb as well as other components, such as salt, lactic acid, and total titratable acidity (TTA), which could affect the flavor. The results of the sensorial analysis indicate that there are no significant differences between the samples. Nevertheless, the content of volatile and nonvolatile compounds shows certain variations that correlate with the flavor scores. In general, the alcohol, ketone, and salt contents are considered positive, whereas the aldehyde and acid contents, including lactic acid, are considered negative. The main conclusions obtained were that for this type of bread, consumers tend to prefer products with a greater degree of fermentation by yeasts, without secondary fermentation by lactic acid bacteria. However, considering the geographic differences regarding these preferences, it will be necessary to perform further tests to establish the acceptance of different types of bread.

Optimization of sourdough process for improved sensory profile and texture of wheat bread

The aim of the study was to determine optimum sourdough process conditions for improved flavour and texture of wheat bread. The influence of process conditions and the starter culture on the characteristics of wheat sourdough bread was established by using response surface methodology. Influence of fermentation temperature (16–32 °C), ash content of flour (0.6–1.8 g/100 g), and fermentation time (6–20 h) were considered as independent factors and their effects were studied in sourdough bread fermented with Lactobacillus plantarum, Lactobacillus brevis, Saccharomyces cerevisiae or with a combination of yeast and lactic acid bacteria. Intensity of sensory attributes, specific volume and bread hardness were considered as the main responses. Ash content of flour and fermentation time were the main factors determining the intensity of sensory attributes. The possibility to enhance intensity of overall flavour, aftertaste and roasted flavour without excessive pungent flavour and without reduced fresh flavour in wheat bread containing 20 g sourdough/100 g of wheat dough was demonstrated by choosing e.g. Lb. brevis for a starter and by utilization of high ash content of flour, long fermentation time and reduced temperature. Bread specific volume was improved 0.2–0.5 ml/g and hardness was reduced (after 4 days of storage) up to 260 g by using low ash content of flour and by optimizing fermentation time according to the microbial strain. Lactic acid fermentation had more profound influence on both desired and undesired flavour attributes, as well as textural features of bread in comparison with yeast fermentation.

Potential of sourdough for healthier cereal products

Sourdough fermentation has a well-established role in improving flavour and structure of bread. However, the significant potential of sourdough fermentation to improve the nutritional properties of rye, oat and wheat products has gained much less attention, although the interest is at present increasing. Sourdough fermentation can modify healthiness of cereals in a number of ways: it can improve texture and palatability of whole grain, fibre-rich or gluten-free products, stabilise or increase levels of various bioactive compounds, retard starch bioavailability (low glyceamic index products) and improve mineral bioavailability. Many new interesting applications for sourdough remain still to be explored, such as the use of prebiotic starter cultures or production of totally new types of bioactive compounds.

The impact of lactic acid bacteria on sourdough fermentation

The baking of sourdough breads represents one of the oldest biotechnological processes. Despite traditionality, sourdough bread has great potential because of its benefits. Sourdough is a mixture of flour and water that is dominated by a complex microflora composed of yeasts and lactic acid bacteria that are crucial in the preparation of bread dough. Lactic acid bacteria cause acidification by producing lactic acid that increases the shelf life of bread by preventing the growth of undesirable microorganisms and affects the nutritional value of bread by increasing the availability of minerals. In addition to these advantages, the use of sourdough fermentation also improves dough machinability, breadcrumb structure and the characteristic flavour of bread. Lactic acid bacteria in sourdough fermentation are well known representing both homofermentative and heterofermentative bacteria. They may originate from selected natural contaminants in the flour or from a starter culture containing one or more known species of lactic acid bacteria. Sourdough can be cultivated in bakeries or obtained from commercial suppliers. However, many bakeries in Europe still use spontaneously fermented sourdoughs, which have been kept metabolically active for decades by the addition of flour and water at regular intervals. The impact of lactic acid bacteria on sourdough fermentation and their influence on dough and bread quality was discussed on the basis of research and literature data.