• Korean Journal of Food Science and Technology
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• v.15 no.3
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• pp.287-294
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• 1983

Change of color, browning index, soluble protein, reducing sugar content, and available lysine were monitored for raw and extruded barely powders during four months of ambient and accelerated storage temperatures with $A_w$ of 0.31 and 0.71, respectively. Loss of whiteness and soluble browning pigments increased with increased $A_w$ and temperature. The raw sample had an increased rate of browning intensity than the extruded samples. Among the extruded samples, the added sucrose sample had the lowest rate of browning during storage. Loss of reducing sugar content in all samples increased with increased $A_w$ and temperature. The loss of soluble protein and of the available lysine also increased with increased $A_w$ and temperature. The loss of reducing sugar and of the available lysine was at least partly due to the Maillard browning reaction. These results have important implications in teh processing and storage of raw and extruded burleys.

• Food Science and Preservation
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• v.6 no.3
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• pp.264-269
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• 1999

The effects of film thickness and moisture absorbing materials(MAM) on the ginger qualities were investigated during MA storage for 150 days. LDPE films of 0.04, 0.06 and 0.08mm thicknesses were applied to select the adequate film in gas permiability. MAMs of sheet and sachet type were applied to 0.06mm-LDPE film bag to prevent moisture condensation during storage. Thickness of film used affected neither weight loss nor firmness of gingers during U storage. But the thinner in thickness showed the less changes in sprouting, spoilage and reducing sugar. Moreover, compared with MAP alone, MAPs with MAM of both sachet and sheet styles led to the weight loss of gingers increasing by more than 3-4 times, but sprouting rate, spoilage rate and reducing sugar decreasing by 3.3, 1.4 and 2.3 times, respectively. These results showed that MAP with UM was significantly effective to prolong the freshness of ginger by longer than 2 times, compared with MAP alone.

• Food Science and Preservation
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• v.8 no.4
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• pp.449-455
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• 2001

Changes in pH, titratable acidity, reducing sugar, nitrogen compound and mineral of black bean chungkugjang(BBC)added with kiwi and radish during fermentation were investigated. During fermentation of BBC, pH was increased, while titratable acidity was decreased. The changes in pH and titratable acidity of all chungkugjangs other than BBC were very rapid after 24 hrs of fermentation. Reducing sugar content was highest in BBC and was increased by 24 hrs of fermentation and decreased thereafter. Amino-type nitrogen increased rapidly after 24 hrs of fermentation. The addition of kiwi and radish increased the content of amino-type nitrogen in BBC by enhancing proteolysis of black bean, being as much as in soybean chungkugjang. At 72 hrs of fermentation BBC was found to be lower in ammonia type nitrogen than soybean chungkugjang. Mineral content, in general, was higher in BBC than in soybean chungkugjang, showing highest in potassium followed by phosphorus, magnesium and calcium.

• Korean journal of food and cookery science
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• v.15 no.5
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• pp.533-538
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• 1999

${\alpha}$-amylase was investigated as an antistaling agent for Backsulgie, a traditional rice cake. Rice powder was mixed with ${\alpha}$-amylase, fermented for 2 hr at 37$^{\circ}C$, and steamed for 20 min. Rice cake was stored at room temperature or freezer for 4 days, and analyzed to determined the changes of chemical and sensory properties. When ${\alpha}$-amylase was added to rice cake, the content of reducing sugars and the yellow color of the cake were increased, and the water activity was decreased. Soft and moist textural properties were apparent in ${\alpha}$-amylase-added rice cakes by sensory evaluation. X-ray diffraction showed a V pattern after 4 days of storage which indicated the starch of rice cake was not retrograded. However, there was no significant difference in moisture content between enzyme-treated and non-treated rice cakes. Above results suggest that ${\alpha}$-amylase treatment produced dextrins which consequently bound with water and inhibited the retrogradation of rice cake.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.10a
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• pp.214.2-215
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• 2003

압출조리 공법에 의한 한국형 쌀 이유식 제조에서 아밀라제 첨가가 압출미분의 물성 변화에 미치는 영향을 알아보았다. 압출조리기의 스크류 회전수는 200rpm, 원료의 사입속도는 180g/min로 고정하여 작동하였다. 원료 쌀가루의 수분함량은 18, 23, 28%로 가수하였고 첨가된 아밀라제는 Bacillus licheniformis로부터 분리한 Termamyl 120LS(NOVO사), Bacillus amylolichuefaciens로부터 분리한 BAN 240L(NOVO사) 및 맥아분말이다. 아밀라제 첨가에 의해 압출미분의 수용성지수는 3배까지 증가했고, 환원당 생성량은 원료의 수분함량에 크게 영향을 받아 28% 수분함량에서 급격히 증가하여 수용성지수와는 다른 경향을 나타내었다. 겔 투과크로마토그래피에 의한 분자량적 구조 변화 측정 결과 아밀라제 첨가에 의해 고분자 획분이 상당히 감소했으며 상대적으로 저분자 획분이 증감함을 알 수 있었다. 아밀라제의 잔존환성은 아밀라제 종류에 따라 다르며 가장 내열성인 Termamyl 120LS의 경우 용융부위 온도 14$0^{\circ}C$에서 27%까지 감소하였다. 침전법에 의한 분산특성은 아밀라제 작용에 의해 수용성 물질이 증가함에 따라 침전층의 감소를 나타내었으나 처리온도가 14$0^{\circ}C$로 증가하면 침전층의 높이는 증가하였다. 겉보기 점도는 아밀라제 첨가에 의해 무처리 압출미분의 1/4~1/200로 감소하였다. 시판 이유식의 권장농도에서의 점도와 같은 점도 수준에 도달하기 위해서는 원료의 수분함량(18, 23, 28%), 아밀라제 종류 및 첨가량, 계량부위 온도에 따른 각 작동조건의 압출미분을 최고 1.8배의 양을 사용할 수 있었다. 이상에서 살펴본 바와 같이 원료 쌀가루에 첨가된 아밀라제가 압출조리기내를 통과하면서 쌀가루의 가수분해를 일으켜 환원당 등 수용성 물질이 증가하고 분산특성이 좋아지며 점도가 낮아지고 결국 이유식의 열량밀도를 증가시킬 수 있음을 확인할 수 있었다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.4
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• pp.617-622
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• 2001

Changes of quality properties of fermented tofu prepared with two molds like Actinomucor elegans (AE) and Rhizopus oligosporus (RO) and coagulants (CaCl$_2$ and citric acid) were investigated. Moisture and crude protein of fermented tofu were rapidly decreased during fermentation, the contents of crude lipid and crude ash were shown to be slightly increased, ad then total acidity was slowly decreased. The content of reducing sugar of fermented tofu was slowly increased for 7 day of fermentation, but rapidly increased after that time because of rapid hydrolysis of carbohydrate in fermented tofu. The contents of amino and ammonia type nitrogen were quickly increased during fermentation. The highest contents of amino type nitrogen of fermented tofu were found in sample of CaCl$_2$group as a coagulant and RO group as a mold. Contents of minerals in tofu fermented for 14 day were high in order of K>Ca>Mg>Na. Iin conclusion, AE was more effective than RO to enhance the contents of reducing sugar and amino type nitrogen as an indicator of fermentation within 7 day of fermentation, and then RO was more effective than AE after that time. Calcium chloride as a coagulant was more effective than citric acid in tofu fermented with the same strain for 14 day.

• Journal of the Korean Society of Food Science and Nutrition
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• v.23 no.1
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• pp.62-67
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• 1994

Spinach has been grown in the bare soil, but nowadays it is generally grown in the greenhouse through four seasons. The kind of spinach is variable and the taste, and nutritive composition of the spinach may be different. In this research, the effect of blanching condition on the chemical composition of winter greenhouse grown spinach was investigated. The mean chemical composition of raw spinach was 3.0% of crude protein, 0.5% of crude fat, 1.0% of crude ash, 12.88mg% of vitamin C, 46.38mg% of phosphorus, 37.95mg% of calcium and 710mg% of oxalic acid. Incresing the balancing time and water volume, the chemical composition contained in spinach was decreased, and especially decreasing range of the oxalic acid was large. When 1% of salt was added, vitamin C was increased.

• Journal of Convergence for Information Technology
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• v.10 no.2
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• pp.102-108
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• 2020

Increasing the rice consumption, seven kinds of Nurungji which served as a home meal replacer and snack were developed with some functional materials were added, and their physiochemical characteristics were analyzed. The water binding capacity was the highest in Nurungji with black sesame seed (264.13%), and the hardness was the lowest as 0.36 N in Nurungji with Tenebrio molitor. The reducing sugar content was the highest in Nurungji with sweet pumpkin (1.47%) when being soaked in water for 30 minutes. As a result of measuring 2,2-diphenyl-1-picryl-hydrazyl free radical scavenging activity of the tested Nurungji preparations, Nurungji with sweet pumpkin and beet showed the high scavenging activity against free radicals. As a result of sensory evaluation, overall acceptability was the highest in Nurungji with black sesame seeds (4.3). Physicochemical characterization and sensory evaluation of Nurongji added with various materials confirmed that they could be applied to various food products.

• Food Science and Preservation
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• v.22 no.5
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• pp.666-673
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• 2015

The quality characteristics of kimchi with Artemisia annua extracts (1~2%; extracted with water or 70% ethanol), including the pH, acidity, reducing sugar content, total viable cell and lactic acid bacteria cell count, and sensory parameters, were investigated at 10 and $15^{\circ}C$ for 20 days during aging. The pH, acidity, reducing sugar content, and lactic acid bacteria count of kimchi with Artemisia annua extract rapidly increased upto the 4~6th day, increasing slowly thereafter. The quality characteristics did not vary between kimchi with and without the extract. The optimal aging time for kimchi with the extract was 10 days at $10^{\circ}C$. The results of the sensory evaluation showed that kimchi with 1% Artemisia annua extract was superior to kimchi with 2% Artemisia annua extract; in particular, the color and taste of the latter were found to be black and bitter, respectively.

• Korean Journal of Food Science and Technology
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• v.19 no.1
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• pp.75-80
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• 1987

In order to prevent browning during drying of garlic flakes, the effect of dipping in phosphate complex solution prior to drying on the development of brown pigment in the flakes were studied. The browning color development during drying of the flakes was greatly dependent on phosphate complex concentration and their dipping time. A reciprocal relationship between browning color formation and reducing sugar content of dried garlic flakes was found. The browning color development during drying of the flakes was effectively impeded by dipping in 0.3% phosphate complex solution for 3 minute. The reduction of pyruvate content during drying of the flakes was greatly influenced by phosphate complex concentration and drying temperature, and a maximum retention was acieved by 3 minute dipping in 0.2-0.3% phosphate complex solution. The dried yield of the flakes dipped in phosphate complex solution was 1.62-1.75% lower than control and it was mainly caused by the dissolution of soluble solids during dipping.