• Korean Journal of Food Science and Technology
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• v.40 no.6
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• pp.643-648
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• 2008

The principal objective of this study was to evaluate the effects of the addition of sourdough to bread dough, specifically with regard to the physicochemical characteristics of bread dough, organoleptic evaluation, and bread storage. Marked increases in lactic acid bacterial counts $10^{9-10}CFU/g$ in dough samples with 30, 50, and 100% of added sourdough to the respective bread dough were observed after the first fermentation period of the dough, but decreases were observed in yeast cells. The highest overall acceptance scores were recorded for the 100% sourdough-added bread, and almost no differences in taste and texture were detected between the regular bread (control bread) and sourdough-added bread on the sensory evaluations, with slightly lower evaluation scores (for sour taste) in the sourdough-added bread. The sourdoughadded bread also showed retarded mold growth in the bread on our storage tests. Six days had elapsed prior to the appearance of mold growth in the sourdough-added bread, whereas three days elapsed in the regular bread. The more sourdough was added to the dough, the less was the total count in bread. Increases of 13.1, 20.9, and 36.2% in the retardation of starch retrogradation of the bread were observed as the result of additional increases in sourdough quantity to bread at 30, 50, and 100%, respectively.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.5
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• pp.625-632
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• 2008

Rye-wheat mixed bread samples made with substitutions of 20, 40, 60 and 80% sourdough, and control made with the addition of naturally fermented raisin extract, were examined for quality characteristics such as pH, total titratable acidity, fermentation power of dough expansion, specific volume, baking loss, water activity, color, texture, external and internal surface appearance, and sensory qualities, in order to determine the optimal ratio of sourdough in the formulation. As the incubation time of sourdough increased, pH decreased, while total titratable acidity increased. The pH of rye-wheat mixed doughs decreased with increasing sourdough content, but total titratable acidity increased. The rye-wheat mixed breads prepared with substitutions of sourdough had higher pH and lower total titratable acidity than the control group. Fermentation power of dough expansion of rye-wheat mixed doughs increased with increasing incubation time. Specific volume was maximum on the 20% substitution sourdough. Baking loss was inferior with the 80% substitution sourdough. Water activity and lightness was minimum on the control group. The higher amounts of sourdough showed the higher tendency of lightness, redness and yellowness. In the texture characteristics, hardness, gumminess, and chewiness was minimum on the control group and tended to increase with higher substitution of sourdough. Substitution of sourdough showed decrease adhesiveness. Fracturability, cohesiveness, and resilience of all rye-wheat mixed breads were not significantly different. Springiness was maximum on the 20% substitution sourdough and minimum on the 40%. A side of loaf of rye-wheat mixed breads, except for 20%, had a poor break and shred. In sensory evaluation, as substitution amount of sourdough increased, the scores of color and consistency of crumb, uniformity of crumb pore, gumminess, and overall acceptability decreased; while the density of crumb pore, springiness of crumb, aroma of rye flour, sourness, and bitterness showed the reverse effect; the 20, 40, and 60% sourdough samples obtained fairly good scores. In conclusion, these results indicated that $20{\sim}60%$ of sourdough could be very useful as a substitute for baker's yeast in developing rye-wheat mixed bread.

• Korean journal of food and cookery science
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• v.31 no.3
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• pp.264-279
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• 2015

The principal objective of this study was to evaluate the effects of the addition of sourdough to various grain flours in bread, specifically, in regards to the physicochemical characteristics of bread dough, sensory evaluation, and bread storage. As the incubation time of sourdough increased, the total titratable acidity increased. Viable yeast counts of sourdough increased consistently until the third day, while lactic acid bacteria counts increased until the second day. The weight of breads containing sourdough made with rye flour, strong flour, and Korean wheat flour were higher than that of the control. However, the height, volume, and specific volume of control were higher than those of the groups with sourdough made with various grain flours. The pH of breads containing sourdough was lower than that of the control, while the total titratable acidity and moisture content were higher than those of the control. In analyzing the visible mold colony during the five days of storage at $30^{\circ}C$, mold growth in breads containing sourdough made of Korean wheat flour, barely flour, and rye flour was retarded. In the color measurement, the L values of the control and bread containing sourdough made with barley flour were higher than that of the other groups after five days. The a value of bread containing sourdough made of rye flour was higher, and the b values of breads containing sourdough made of Korean wheat flour, barley flour and rye flour were higher than those of the other groups after five days. The hardness of breads containing sourdough increased as storage time increased, where as breads containing sourdough made of Korean wheat flour, Korean whole wheat flour, and rye flour revealed no significant differences with control group. Sensory evaluation scores in terms of after swallowing, taste, and overall preference of bread containing sourdough made of Korean wheat flour was higher than those of the control group.

• Culinary science and hospitality research
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• v.23 no.4
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• pp.56-65
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• 2017

This study investigated quality characteristics of sourdough bread using fermented fig. Bread containing sourdough, compared with control group, showed high inclination in moisture content. Sample with 20% of sourdough was the highest, and sample with 40% of sourdough was the lowest. There was a significant difference among samples. As for appearance and cross structure of sourdough bread with fermented fig, there was an inclination that the bigger sourdough bread is, the bigger cell is and the more even its structure is. As for the chromaticity, sample with 20% of sourdough showed the lowest value of L and value of b. Value of L and b got lower as its volume got bigger. Value of a, on the one hand, showed no fixed inclination. As for textural characteristics, sourdough bread showed lower hardness, cohesiveness, and gumminess, and higher springiness and cohesiveness than control group. There were significant differences among all items, but there was no significant difference in hardness, springiness, cohesiveness, and gumminess among samples. Changes in result of sensory analysis suggested that sample with 20% of sourdough showed the highest overall preference including color, flavor, taste, and appearance. On the other hand, sample with 40% of sourdough showed the lowest overall preference. Considering preference through sensory analysis and quality characteristics of sourdough bread with fermented fig, therefore, it seemed that sourdough bread with 20% of sourdough had the best characteristics.

• Korean Journal of Food Science and Technology
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• v.47 no.6
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• pp.704-710
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• 2015

The objective of this work was to examine the effect of rice flour sourdough fermented with omija (Schizandra chinensis) extract on the quality characteristics of bread. Five rice sourdough concentrations (0, 15, 30, 45, and 60%) were used in order to ascertain the best bread composition. Bread qualities were determined by means of physicochemical analysis and consumer acceptability test. The results showed that the dough prepared with 15% rice flour sourdough fermented with omija extract had a positive impact on the bread quality such as volume, hardness, springiness, and consumer acceptability. This study suggests that the rice flour sourdough fermented with omija extract could be added up to 15% without quality changes for making bread.

• Culinary science and hospitality research
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• v.15 no.4
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• pp.37-46
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• 2009

The purpose of this study is to investigate if Korean wheat flour(KWF) can be used a sourdough ingredient. Gluten contents, pH levels, TTA levels, fermentation rates, mixograph, crumbScan and sensory evaluation were analyzed. The pH levels of sourdough starters ranged from 4.0 to 4.5 throughout all kinds of KWF, and they proved to be available as a sourdough starter. KWF 5 and KWF 6 showed the higher fineness and elongation of crumb grain than any other kind of Korean wheat flour, which were considered appropriate for making bread. KWF 6 scored good mark in the sensory evaluation for texture of crumb and color of crust among all kinds of KWF. In conclusion, although the sourdough bread with sourdough starter SF of bread flour showed the best result in the evaluation, KWF 6 was considered as a good sourdough starter since the result was shown better than CON.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.218-228
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• 2015

In this study, the physicochemical characteristics of rice sourdough fermented with Omija extract were investigated. Rice sourdough was made with a 3 stage fermentation process. pH & total titratable acidity, numbers of yeast and lactic acid bacteria, and dough expansion rate were measured. In addition, an RVA was employed to study the pasting properties of rice sourdough. There was a significant (p<0.05) change in both the pH of rice sourdough, which decreased from 5.08 to 3.98, and total titratable acidity, which increased from 0.20 to 0.57 (0.1N NaOH mL), as fermentation time increased. The amount of yeast and lactic acid bacteria significantly increased from 6.73 to 7.65 log CFU/g, 6.93 to 7.65 log CFU/g, respectively(p<0.05). The expansion rate of rice sourdough fermented with Omija extract was higher than rice sourdough fermented without Omija extract. The initial pasting temperatures of rice sourdough fermented with Omija extract were decreased from $91.3^{\circ}C$ to 85.6. The final viscosity and setbacks decreased as fermentation time increased. These results suggest that Omija extract has a beneficial effect on increasing the expansion rate of rice sourdough as a substitute for wheat flour.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.9
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• pp.1215-1221
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• 2009

The purpose of this work was to improve the quality of Jeungpyun made with rice sourdough, which was prepared using a mixed culture of Saccharomyces cerevisiae (S. cerevisiae) and Leuconostoc mesenteroides (L. mesenteroides) strains, and to also develop a new process for Jeungpyun preparation using the rice sourdough. The Jeungpyun was manufactured through proofing for 3 hr at $30^{\circ}C$ and steaming steps after mixing the ingredients, including pre-fermented rice sourdough, rice powder and water. After proofing, the expansion ratio of the Jeungpyun dough ranged from 109 to 135% and the pH was decreased to pH 3.80$\sim$4.09. The volumes of the Jeungpyun samples prepared with rice sourdough were 18$\sim$45% greater than that of the control. In particular, the Jeungpyun made with rice sourdough containing 10% brown rice (CM-10) had a significantly greater volume (266 mL). Also the rice sourdough Jeungpyun samples had well developed dense porous structures compared to the control. According to sensory evaluations, the sample prepared with rice sourdough containing 10% brown rice was preferred. Finally, the physical quality (texture properties) and microbiological shelf-life of the Jeungpyun was improved by using the rice sourdough.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1896-1905
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• 2014

The purpose of this study was to manufacture white bread by substituting bakery yeast with natural starter. The general composition of wild grape, was 81.22% moisture, 0.81% ash, 0.74% crude fat, 1.58% crude protein, and 15.65% carbohydrate contents. Fermented wild grape extract was made by culturing for 4 days at $25^{\circ}C$. Flour was added three times to fermented wild grape extract and incubated for 36 hours at $20^{\circ}C$ to manufacture sourdough. We investigated the quality characteristics of white bread with different amounts of fermented wild grape sourdough. The pH of dough decreased with increasing amounts of sourdough, whereas total titratable acidity of dough significantly increased. Fermentation power of dough expansion significantly increased with increasing incubation time, and control showed the highest value of 126.67%. White bread specific volume was highest in, 50% sourdough at 4.76 mL/g. Water content increased with increasing amounts of sourdough, whereas water activity was not significantly different between the samples. For texture, hardness of 50% sourdough was lowest at 19.23 g. In the sensory evaluation, color, flavor, softness and overall acceptability decreased with increasing amounts of sourdough. As a result, 50% sourdough can be considered as a baker's yeast substitute for making natural fermented bread.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.6
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• pp.996-1008
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• 2009

In this study, domestic wheat flour was used to develop a native sourdough suitable for the Korean environment, in an attempt to replace the sourdough starter that are currently available in local markets and used to prepare sourdough breads. Nine kinds of domestic wheat flour (available at local market) were examined and to characterized according to their general ingredients, gluten contents, colorimetry data and mixograph measurement. In addition, the flour were used to make sourdough starters that were assessed for pH, TTA, and fermentation rate from which an optimal sourdough starter could be chosen. This study also compared the product characteristics breads prepared from the with one another by adding extracted sourdough starters. In order to analyze the quality characteristics of the breads, a comparative analysis was conducted through on data for dough fermentation rate, specific volume, texture analyses, colorimetry, water activity and sensory tests. According to the results, the sourdough starters KWF 3, KWF 4 and KWF 5 scored well in evaluations for gluten content, wheat flour characteristics and pH, and were deemed the most optimal starters. To characterize the sourdough breads prepared from KWF 3, KWF 4, and KWF 5, their quality characteristics were analyzed and then compared to those sourdough bread (control group) prepared using a sourdough starter made from imported wheat flour. According to the comparative analysis of the quality characteristics, KWF 4 had the largest volume and specific volume, but had the lowest textural hardness, indicating the softest texture of overall. According to sensory tests, the bread prepared from KWF 4 was significantly more preferred than the other specimens.