• 한국식품조리과학회지
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• 제14권3호
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• pp.261-265
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• 1998

증편의 발효시 일어나는 이.화학적 성질의 변화는 발효 중 생성되는 $\alpha$-amylase의 활성과 밀접한 관계를 가지고 있을 것이다. 이에 본 연구에서는 콩물과 발효시간에 따른 증편 반죽 내의 $\alpha$-amylase 활성과 특성을 측정하였다. 콩물과 증편 반죽에는 생전분과 호화전분을 기질로 하는 $\alpha$-amylase가 존재함이 밝혀졌다. 콩물 $\alpha$-amylase 의 호화전분과 생전분에 대한 $\alpha$-amylase의 비활성도는 각각 0.79 units/mg protein, 0.036 units/mg protein 이었다. 콩물의 $\alpha$-amylase는 호화전분과 생전분에 대해 pH 5.92, 6.87과 6$0^{\circ}C$에서 최대 활성을 나타내었다. 증편 반죽의 호화전분과 생전분에 대한 $\alpha$-amylase의 최적 pH는 5.25였고 최적 온도는 5$0^{\circ}C$였다. 증편 반죽내의 $\alpha$-amylase의 활성은발효 시간에 대해 일정한 경향을 가지고 있지 않았다. 콩물을 첨가한 반죽의 호화전분에 대한 $\alpha$-amylase의 비활성도는 평균 25.59 units/mg protein이었고 생전분에 대한 $\alpha$-amylase의 비활성도의 평균은 1.37 units/mg protein이었다. 콩물을 첨가하지 않은 반죽에서의 호화전분과 생전분에 대한 $\alpha$-amylase의 비활성도는 각각 3.37 units/mg protein, 0.49 units/mg protein이었다. $\alpha$-amylase의 활성은 기질에 상관없이 콩물 첨가한 군이 그렇지 않은 군보다 유의적으로 높았다(p<.05).

• 한국식품조리과학회지
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• 제13권4호
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• pp.484-491
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• 1997

증편 반죽에서 일어나는 일련의 이화학적 성질의 변화간의 연관성과 발효시 증편 반죽의 이화학직 성질의 차이가 증편 제조 후 저장 중의 품질 변화에 미치는 영향을 연구한 결과는 요약하면 다음과 같다. 증편 반죽의 pH는 발효가 진행되면서 PH 5.96∼4:36 사이에서 계속 감소하였다. 설탕첨가군의 경우 그렇지 않은 군보다 pH 변화가 완만했으나 유의적인 차이는 없었다. 증편 반죽의 부피는 발효시간에 따라 증가했으며 발효가 반복될수록 최대 부피에 도달하는 시간이 짧아졌으며 최대 부피는 커졌다. 평균 부피는 콩물을 첨가한 군이 대조군에 비해 유의적으로 컷다(p<.05). 반죽의 점도는 발효초기에 감소하였다가 콩물 첨가군의 경우 발효 2시간 이후 급격히 증가하였으며 대조군의 경우 1차 발효 후부터 급격히 증가하였다. 반죽내의 환원당량은 설탕 총 첨가량의 1/2만 처음부터 넣은 군의 경우, 완만한 증가를 보이다가 감소하였고, 2차 발효후 다시 증가하였다. 대조군의 경우, 1차 발효시까지는 증가하였고 1차 발효 후 다시 감소하였다. 환원당량의 변화양상은 설탕 총 첨가량의 1/2만 처음부터 넣은 군과 대조군 사이에서 유의한 차이를 보였다(p < .05). 관능검사를 통한 증편의 저장시 품질의 변화를 연구한 결과 저장기간에 따라 모든 군의 경도는 증가하였고 부드러운 정도, 탄력성, 촉촉한 정도, 전체적인 수응도 등은 감소하였다. 그러나 콩물을 첨가한 군은 그렇지 않은 군보다, 또한 설탕 총 첨가량의 1/2만 처음에 첨가한 군은 그렇지 않은 군보다 이러한 변화가 서서히 일어났다. QTS로 texture를 측정한 결과 저장기간에 따라 경도, 검성, 씹힘성은 증가했으며 부착성은 감소하였다. 이러한 변화는 콩물을 첨가한 군에서그렇지 않은 군보다 서서히 일어났다.

• 한국식품조리과학회지
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• 제24권6호
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• pp.837-848
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• 2008

The objectives of this study were to investigate the quality of ginseng makgeolli during the fermentation and aging period, and to develop Jeungpyun manufactured by ginseng makgeolli. Four different amounts of ginseng powder (0, 2, 4 and 6 g) were added to the filtered mash which was fermented for 4 days at $24^{\circ}C$ and then aged for 6 days at $4^{\circ}C$ The quality of Jeungpyun batter containing 0, 2, 4 and 6% ginseng during fermentation, and the sensory, color and textural characteristics of ginseng Jeungpyun were analyzed. The pH of jeungpyun batter without ginseng was lower than the other batters. During 4 hours of fermentation of the batter at $30^{\circ}C$, the pH of the batter significantly decreased. The expansion volume of the batter without ginseng increased 4.11 times after 4 hours of fermentation, whereas batters with 2, 4, and 6% ginseng increased 1.70 times. The L value of Jeungpyun decreased by increasing the concentration of ginseng However the a and b values of Jeungpyun significantly increased with an increase in the concentration of ginseng. The results of the sensory evaluation showed that Jeungpyun with 2% ginseng had the highest flavor, taste and overall acceptability scores. In the textural analysis, the hardness of Jeungpyun increased by increasing the concentration of ginseng after 6 days of storage at $20^{\circ}C$. This study showed that Jeunpyun containing 2% ginseng was the optimum addition level.

• Food Quality and Culture
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• 제2권1호
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• pp.43-47
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• 2008

This study examined the quality characteristics of Jeungpyun prepared with different additions of nano-filtered (NF) tofu whey concentrates. The initial pH values of the Jeungpyun batters ranged from 5.64 to 5.78, and decreased to 4.77-4.98 after 4 hours of fermentation at $35^{\circ}C$. The volume and specific volume values of the control Jeungpyun were lower than those of Jeungpyun samples prepared with 1%, 2%, and 3% NF powder. The color of the Jeungpyun became increasingly greenish-yellow as the NF powder level increased. Hardness and brittleness decreased with increasing NF powder content, while cohesiveness and springiness were not significantly different. Sensory evaluations revealed that as the level of NF powder increased, takju smell and sourness increased, but no significant differences were observed for sweetness and moistness between the control and NF powder groups. In terms of overall acceptability, the results revealed that Jeungpyun can be prepared with up to 1% NF powder in place of rice powder and be deemed as acceptable as a control Jeungpyun product.

• 한국식품조리과학회지
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• 제21권6호통권90호
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• pp.782-793
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• 2005

This study investigated the effect of $2\%$ addition of pectin and alginate on the Physicochemical and retrogradation Properties of Jeungpyun, a Korean traditional fermented rice cake. The volume of batters with alginate and Pectin was significantly larger than that of control. Jeungpyun samples with Pectin and alginate had a larger volume with uniform and smaller cell size. All samples showed largest foaming capability after second fermentation. Foaming capability of the control ($0\%$ addition of pectin and alginate) was significantly larger than that of the treated samples. The amount of reducing sugar tended to increase during fermentation but decreased after steaming, which was due to the increase in hydrolysis of starch. On the contrary, the content of free sugar was slightly decreased during fermentation but slightly increased after steaming. The control contained the largest amount of free sugar after steaming. The microstructure of starch particles after fermentation showed completely dispersed starch granules with air bubbles. After steaming, the structure was sponge-like in all samples. Samples with added alginate and pectin had significantly higher water binding capacity than those of the control. All samples showed noticeably increased solubility and swelling power at $70^{circ}C$ with the control being significantly lower than the treated samples. Retrogradation was measured with $\alpha$-amylase and the retrogradation process of the sample with added alginate and pectin proceeded slower than that of the control. The relative crystallinity was observed through X-ray diffraction method and samples with added alginate and pectin had smaller crystallinity and delayed retrogradation compared to the control. Thus, Jeungpyun with the addition of alginate and Pectin demonstrated improved functionality and dietary fiber addition effect. The storage period of was extended as the retrogradation rate was delayed by the addition of dietary fibers.