본 연구는 특색 있고 독특한 향미를 지니며 건강지향적인 재료를 찾는 소비자들에게 생소하지만 영양성분이 풍부한 테프를 활용하여 sourdough bread 제조에 적용하고, 효소(α-Amylase, glucose oxidase)를 첨가하여 더 좋은 품질로 향상시켜 테프를 제과제빵 제품에서 좀 더 활용도가 높게 사용할 수 있도록 학문적 기초자료로 제시하고자 본 연구를 실시하였다. 본 연구는 사워스타터를 첨가하지 않은 대조군(이하 CON으로 명명)과 사워스타터 100%로 만든 대조군(이하 T0로 명명)을 나누어 대조군이 2가지 형태로 존재한다. 실험은 크게 세 가지로 구성되었으며, 첫 번째 실험에서는 테프 분말로 사워스타터를 제조한 후 테프 첨가량을 달리하여 sourdough bread(강력분 대비 테프 분말 5%, 10%, 15%, 20%를 첨가)을 만들고, 반죽의 제빵 적성 및 제품의 품질 특성을 살펴보았다. 두 번째 실험에서는 첫 번째 실험 결과로 통해 확인한 최적 배합비(TP10)에 효소 첨가량(A1: α-Amylase 0.890 U/g, α-Amylase 1.780 U/g, O1 : glucose oxidase 2.5 U/g, O2 : glucose oxidase 5.0 U/g)을 달리하여 sourdough bread를 만들어 반죽의 제빵 적성 및 제품의 품질 특성을 확인하였다. 세 번째 실험에서는 첫 번째 실험과 두 번째 실험을 통해 확인된 테프와 효소를 첨가한 최적 배합비의 시료들만을 모아 관능검사(기호도 검사, 정량적 묘사분석)를 진행하였다. 본 연구 결과를 요약하면 다음과 같다. 테프와 효소를 첨가한 sourdough bread의 품질 특성을 알아보기 위해 테프 첨가량에 따른 sourdough bread 제조 시 사워스터터를 첨가하지 않은 대조군(CON)과 사워스타터 100%를 만든 대조군(T0)과 비교한 결과, 테프 분말을 10% 첨가한 sourdough bread(TP10)가 부피가 크고 부드러웠으며 기호도에서도 A1 다음으로 가장 좋은 평가를 받아 sourdough bread 제조에 적합한 것으로 확인되었다. 효소를 첨가한 테프 sourdough bread의 품질 특성에서는 α-Amylase 첨가로 인해 저장성 면에서 경도가 낮아져 부드러워지며 수분함량이 증가하고 껍질두께가 감소하여 노화 지연에 긍정적인 영향을 미친다고 나타났으며, glucose oxidase 첨가로 인해서는 반죽 완료 및 1차 발효 pH를 감소시켜 점탄성이 더 우수한 반죽이 되어 발효 팽창력을 촉진하고 탄력 있는 최종 제품이 된다고 나타났다. 결과적으로 테프의 활용성을 높이기 위해서 테프를 이용하여 사워스타터를 만들고, sourdough bread를 제조할 때 TP10이 가장 제빵 적성이 우수한 빵이 나왔으며 강력분 대비 테프를 대체한 sourdough bread에서 부족한 부분을 효소를 활용하여 보완함으로써 뛰어난 품질 특성을 가진 빵을 제조할 수 있었다. 이러한 결과로 제빵 산업에서 테프를 좀 더 효과적으로 활용하기 위해서는 효소를 제품에 접목시키고, 더 심층된 연구를 통해 우수한 제품을 생산할 수 있을 것으로 사료된다.
This study is unfamiliar to consumers who are looking for health-oriented ingredients with full-bodied characteristics and unique flavor, but it can be easily applied to the manufacture of sourdough bread by adding both a nutrient-rich teff and enzymes(α-Amylase, glucose oxidase). This study was conducted in order to provide the basic academic data so that teff can be used more highly in confectionery and bakery products through the improvement of its overall quality. In this study, a control group without sour starter was added(here in after referred to as CON) and a control group made with 100% sour starter(here in after referred to as T0) exist in two forms. The experiment that was conducted consisted largely of three main things. In the first experiment, after making a sour starter with Teff Powder, sourdough bread(5%, 10%, 15%, 20% Teff Powder compared to a strong flour) was made by varying the amount of teff added to the mix. The quality characteristics of the dough and the final product were then examined. In the second experiment, sourdough bread was made by varying - 208 - the amount of enzyme added to the optimal blending ratio(TP10) identified by the first experiment result, and the quality characteristics of the dough and product were then confirmed. In the third experiment, a sensory test(acceptance test, quantitative descriptive analysis)was conducted by only collecting specific samples of the optimum mixing ratio to which the teff and enzyme were added, which were confirmed through the first and second experiments. The summary of this study is as follows. First experiment: Quality Characteristics of Sourdough Bread added with Different Quantities of Teff Powder The pH at the time of the completion of the dough, the pH after the first fermentation, and the pH of the finished product, all showed a tendency to increase significantly as the amount of teff added into the mix increased. After the first fermentation, the pH was lower than the pH of the finished dough, but increased again when the inner quality of the finished product was measured. In comparison to CON and T0, after 90 minutes, the removal efficiency of TP10 steadily increased, from 105 minutes, except for TP5, TP10, and T0, the removal efficiency of the remaining samples decreased. In addition, 10% is considered an appropriate amount that has a good effect on the fermentation process. As a result of the TPA analysis, CON showed low values of hardness, adhesiveness, springiness, and cohesiveness, and low chewiness, gumminess, and resilience. T0 showed the highest values of hardness, chewiness, and gumminess. As a result of analyzing the remaining samples, it is believed that adding a certain amount of sour starter and adding Teff Powder affects all textures except for the adhesion of sourdough bread. As a result of the image analysis, T0 showed the highest grain fineness, and the remaining samples showed a tendency to increase as the amount of teff added increased. In general, CON and T0 showed significant differences from the rest of the samples in terms of grain elongation and crust - 209 - thickness. In the volume and specific volume of sourdough bread, TP10 was the largest, and moreover, there was a significant difference between each of the samples(p<0.001). When analyzing the chromaticity based on CON and T0, the brightness (L value) of the crumb became darker as the amount of Teff Powder added increased, and the a value and the b value of the crumb showed a tendency to increase as the amount of Teff Powder added increased. The brightness of the crust decreased as the amount of Teff Powder increased, and the a and b values tended to decrease as the amount of Teff Powder added increased. Moisture content showed a tendency to decrease as the amount of Teff Powder added increased. In terms of storage test, as the amount of Teff Powder added increased, the hardness of the sample increased and the moisture content decreased, and as time passed, the shelf-life decreased. Second experiment: Effect of Enzymes on the Quality Characteristics of Teff Sourdough Bread As a result of confirming the research results on the quality characteristics of sourdough bread with added Amylase, the pH was TP10, A1, A2, T0 than CON without sour starter at all stages(right after dough completion, immediately after first fermentation, and finished product) all measured significantly lower. In the case of fermentation efficiency, the dough containing α-Amylase showed lower fermentation expansion power, when compared to CON at the beginning of fermentation, however, A1 showed high fermentation expansion power after 75 minutes of fermentation, and A2 showed higher expansion power 90 minutes after fermentation. As a result of TPA, the addition of α-Amylase reduced the hardness, adhesiveness, springiness, and cohesiveness of A1 and A2, rather than TP10, and it also reduced chewiness, gumminess, and resilience. As a result of image analysis, the addition of the enzyme α-Amylase reduced grain fineness, grain elongation, and crust thickness. The volume and specific volume tended to increase as the amount of α-Amylase added increased. In chromaticity, samples added with α-Amylase(A1, A2) significantly decreased the brightness of the crumb and the crust, and the red a value and yellow b value of the crumb also increased. As the amount of α-Amylase added increased, the redness of the crust increased, but the yellow b value of the crust tended to decrease. Moisture content showed a tendency to decrease in the amount of α -Amylase being added, but it was confirmed that A1 had a higher moisture content than TP10, so that the moisture content increased. In terms of storage test, the hardness and moisture content of the sample(A1) added with α-Amylase tended to increase, when compared to TP10, indicating that the shelf-life was improved and the aging was delayed. As a result of confirming the results of the research focused on the quality characteristics of sourdough bread with glucose oxidase being added, the pH was TP10, O1, O2, when compared to CON without sour starter at all stages(right after dough completion, immediately after first fermentation, and finished product). In addition, T0 was measured significantly lower. The fermentation efficiency of dough containing glucose oxidase showed somewhat of a lower fermentation expansion power, when compared to CON at the beginning of fermentation, but the fermentation expansion power of both O1 and O2 steadily increased. In TPA, O1 and O2 increased hardness, adhesiveness, and chewiness than that of TP10. Moreover, image analysis showed that the samples(O1, O2) to which glucose oxidase was added, when compared to TP10 showed significant differences in grain fineness, grain elongation, and crust thickness, especially when glucose oxidase was added. It was confirmed that the lowered and the elongation of the grains also increased. The volume and specific volume showed a tendency to decrease as the amount of glucose oxidase added increased. As the amount of glucose oxidase increased, the crumb eventually became darker and darker, and the redness and b value of the crumb also tended to decrease. As the amount of glucose oxidase increased, the crust brightness decreased, the redness of the crust increased, and the b value decreased. Moisture content tended to increase as glucose oxidase was added. The hardness of sourdough bread O1 added with glucose oxidase was lower than that of TP10, when compared to TP10 until 48 hours of storage. It appeared to contain more moisture than bread, and it is thought that the addition of glucose oxidase delays the aging process. Third experiment: Sensory Characteristics of Sourdough Bread added with Teff and Enzymes As a result of analyzing the acceptance test results, among the samples to which the sour starter was added, A1 showed a similar result to CON, showing little significant difference. In particular, when compared to TP10, enzymes(α-Amylase, glucose oxidase) added samples(A1, O1) showed high values, which is thought to be able to produce better bread with improved nutritional and functional aspects. As a result of quantitative descriptive analysis, 20 descriptive words out of a total of 25 descriptive words(volume, crust color, crumb color, grain size, grain uniformity, vortex or crumb, roughness of crumb, moisture of crumb, hardness, degree of tearing, moisture, adhesiveness, jjolgit, chewiness, fermented smell, flour smell, sweet taste, salty taste, sour taste, and tub-tub), and 5 descriptive words(springiness, savory cereal smell, yeast smell, sweet smell, caramel smell, bitter taste), did not show any significant difference between samples. As a result of the analysis of the main components of the sensory properties, T0 was located in the positive(+) direction of the first main ingredient, and CON was located in the negative(-) direction of the first main ingredient, and it was clearly distinguished, which was in accordance to the properties of the added Teff Powder and enzymes. Considering that the location of T0 was located at the edge of the positive(+) direction of the first main ingredient, the sour taste, bitter taste, crumb color, fermented smell, roughness of crumb, after mouthfeel(tub-tub), as well as hardness are all representative characteristics of T0. CON is located at the edge of the negative(-) direction of the first main ingredient, and it can be said that the volume, degree of tearing, sweet smell, flour smell, adhesiveness, moistness of crumb, moisture, chewiness, jjolgit and so on, are all representative characteristics of CON. It was confirmed that A1, O1, and TP10 were located in the center relatively far away from CON and T0, so the strength of the characteristics were not strong. As a result of partial least square regression analysis(PLSR) analysis, TP10, A1, and O1, which did not exhibit too strong of characteristics in the production of sourdough bread with Teff Powder and enzyme added, showed a positive evaluation in taste and overall acceptability, when compared to CON. Furthermore, it was considered to be visible, and the difference between the characteristics from T0, which were clearly different, could be easily recognized. In the future, when Teff Powder and enzymes are used for making sourdough bread, it is believed that the overall acceptability can be improved if the sour starter''s unique sour flavor and texture are complemented.
I. 서 론 11. 연구 배경 및 연구 목적 12. 연구 구성 6Ⅱ. 문헌고찰 81. 테프 81) 테프의 개요 82) 테프의 성분 및 특성 103) 테프를 활용한 선행연구 132. 사워도우 211) 사워도우의 개요 및 특성 212) 사워도우를 활용한 선행연구 243. 효소(Amylase, Glucose oxidase) 321) 효소(Amylase, Glucose oxidase)의 개요 및 특성 322) Amylase를 활용한 선행연구 403) Glucose oxidase를 활용한 선행연구 47Ⅲ. 재료 및 방법 511. 실험 재료 512. 실험 방법 521) 사워스타터의 제조 및 분석 52(1) 테프 사워스타터의 pH 52(2) 테프와 강력분을 이용한 사워스타터의 pH 55(3) 온도 변화에 따른 테프 사워스타터의 pH 57(4) 사워스타터의 pH 592) 테프 sourdough bread의 제조 및 분석 60(1) 테프 sourdough bread 제조 60(가) 1차 발효 수준의 결정 60(나) 2차 발효 수준의 결정 61(다) 테프 첨가량을 달리한 sourdough bread 제조 61(라) 효소를 첨가한 테프 sourdough bread 제조 62(2) 발효율 69(가) 테프 첨가량을 달리한 sourdough 반죽의 발효율 69(나) 효소를 첨가한 테프 sourdough 반죽의 발효율 69(3) pH 측정 70(가) 사워스타터의 pH 70(나) 반죽의 pH 70(다) 식빵 속질의 pH 70(4) 조직감 71(5) 영상 분석 72(6) 높이, 부피, 비용적 72(7) 색도 72(8) 수분함량 73(9) 저장성 733) 관능검사 73(1) 관능검사용 시료 제조 74(2) 기호도 검사 76(3) 정량적 묘사분석 76(가) 패널의 선발 및 훈련 76(나) 묘사분석의 용어 개발 및 선택 78(다) 시료의 준비 및 제시 81(라) 평가 내용 및 절차 81(4) 관능적 특성에 대한 주성분 분석(PCA) 81(5) 부분 최소평방 회귀분석(PLSR) 824) 통계처리 82Ⅵ. 결과 및 고찰 831. 사워스타터의 pH 831) 테프 사워스타터의 pH 832) 테프와 강력분을 이용한 사워스타터의 pH 863) 온도 변화에 따른 테프 사워스타터의 pH 882. 테프 첨가량을 달리한 sourdough bread의 품질특성 901) pH 902) 발효율 933) TPA 984) 영상 분석 1035) 높이, 부피, 비용적 1066) 색도 1087) 수분함량 1128) 저장성 1143. 효소를 첨가한 테프 sourdough bread의 품질특성 1201) α-Amylase를 첨가한 테프 sourdough bread의 품질특성 120(1) pH 120(2) 발효율 122(3) TPA 126(4) 영상 분석 129(5) 높이, 부피, 비용적 131(6) 색도 133(7) 수분함량 135(8) 저장성 1362) Glucose oxidase를 첨가한 테프 sourdough bread의 품질특성 140(1) pH 140(2) 발효율 142(3) TPA 146(4) 영상 분석 148(5) 높이, 부피, 비용적 150(6) 색도 152(7) 수분함량 154(8) 저장성 1554. 관능검사 1591) 기호도 검사 1592) 정량적 묘사분석 1633) 관능적 특성에 대한 주성분 분석 1714) 부분 최소평방 회귀분석(PLSR) 174Ⅴ. 요약 및 결론 1761. 요약 1762. 학문적 시사점 1813. 실무적 시사점 1824. 연구의 한계점 및 향후 연구에 대한 제안 183참 고 문 헌 184Appendix 199Abstract 207
