• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.3
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• pp.333-341
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• 2008

The objective of this study was to investigate the physical characteristics of sourdough starter containing red koji rice (SD1: 0%, SD2: 10%, SD3: 20% and SD4: 40%) and to compare the quality characteristics of sourdough breads containing 10% red koji rice powder with those of sourdough bread containing with vollsauer powder (VPB) and white wheat bread (WWB) prepared with starter SD1. The activity of ${\beta}$-amylase increased with increasing amount of red koji rice. Organic acids of sourdough starter with red koji rice (SD2, SD3 and SD4) were higher than that of sourdough starter SD1. The peak time, peak value width of tail, pH, and L value were high in WWB, while the proofing power and a and b values of WWB were lower than those of VPB and sourdough bread containing SD1 (SPB1), SD2 (SPB2), SD3 (SPB3), or SD4 (SPB4). The lowest pH, baking loss, and specific volume were observed with the VPB. The baking loss of SPB4 (sourdough bread containing SD4) was the highest (13.01%). Overall, hardness and springiness were low in sourdough bread containing red koji rice powder, whereas sourness and off-flavor were higher than in VPB. Results of specific volumes, hardness and sensory evaluation indicated that the addition of 10% red koji rice powder to sourdough starter can improve the quality characteristics of the sourdough bread.

• Food Science and Preservation
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• v.24 no.6
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• pp.727-733
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• 2017

We investigated the effect of PE film thickness on the modified atmosphere packaging (MAP) deastringency of 'Sanggamdungsi' (Diospyros kaki cv.) astringent persimmon at room temperature ($25^{\circ}C$) and low temperature ($-1^{\circ}C$). The fruits were individually packaged with PE film of which the thickness is 60, 80, 100, 115 or $130{\mu}m$ and stored at room or low ($-1^{\circ}C$) temperature. At room temperature, firmness shows the highest value (23.3-26.5) at $100{\mu}m$ thickness. Top flesh browning and decay was monitored at 20 days after storage, and peel blackening and style-end softening was negligible at optimal thickness. Therefore, optimal film thickness of deastringency at room temperature is $80-100{\mu}m$. At this thickness, the astringency was removed after 5 days and the fruits can be distributed until 10 days after the MAP. At low ($-1^{\circ}C$) temperature, firmness was maintained regardless of film thickness. However, the firmness is higher as the film is thicker. Top flesh browning and decay was not occurred even after 90 days after storage. Peel blackening and style-end softening was monitored at 90 days after storage. Off-flavor was monitored at 115 and $130{\mu}m$ thickness. Therefore, optimal film thickness of deastringency at low ($-1^{\circ}C$) temperature is $80-100{\mu}m$. At this thickness, the astringency was removed after 50 days and the fruits can be distributed until 80 days after the MAP.