엉겅퀴 물 추출물을 이용한 젖산발효 특성 및 제품개발

다국어 초록 (Multilingual Abstract)

In this study, we made fermented thistle syrup that increased useful components. For this purpose optimum drying condition of thistle was set by comparing drying time and color value, and extraction condition was set by comparing antioxidant activity of extract The lactic acid bacteria for thistle extract fermentation was selected by comparing physicochemical properties, microbial changes, antioxidant activity and useful components.
In order to prepare the starter culture medium for the production of fermented thistle syrup, the composition of the medium was selected by comparing the number of microorganisms according to the composition of the medium, and physicochemical properties, antioxidant activity, useful component content and sensory test of fermented thistle syrup were investigated.

1. Drying condition of thistle were suitable at 70℃ for 4hours and color values was L : 40.36, a : -7.75 and b : 15.08.

2. Water extraction condition of thistle were suitable at 100℃ for 4 hours that shoed better antioxidant activities than other conditions. The antioxidant activities of selected water extraction condition of thistle showed 0.95 mg/g of total phenolic contents, 0.73 mg/g of total flavonoid contents, 46.63% of DPPH radical scavenging activity and 51.32% of ABTS radical scavenging activity.

3. Results of preliminary test, Lactobacillus plantarum and Leuconostoc mesenteroides were selected as thistle fermentation bacteria. Theses bacteria shoed better physicochemical properties and antioxidant activities than other bacteria.

4. As a result of fermentation of thistle extract with Lactobacillus plantarum and Leuconostoc mesenteroides, Leuconostoc mesenteroides showed higher lactic acid bacteria numbers Lactobacillus plantarum. but Lactobacillus plantarum showed better titratable acidity and pH than Leuconostoc mesenteroides. Total phenolic content showed similar content but total flavonoid contents showed higher contents at Lactobacillus plantarum. Leuconostoc mesenteroids showed decreased cirsimarin and cirsimaritin contents during fermentation, but Lactobacillus plantarum showed 15% increased cirsimaritin contents after 24 hours fermentation.
Through the above results, we selected Lactobacillus plantarum as thistle fermentation bacteria which showed higher titratable acidity, total flavonoid content and cirsimaritin contents than Leuconotoc mesenteroides.

5. As a result of lactic acid fermentation after add different concentration of sugar to thistle extract, sugar add showed no significant changes in total phenolic content and total flavonoid content, but the content of cirsimaritin tended to increase and then condition of 12 °Brix showed higher cirsimaritin content about 70% than non-fermented condition.

6. Mixing ratio to make medium for starter culture of thistle extract and malt extract was suitable 75:25, and carbon source add showed lower bacteria growth rates than no carbon source add. And the addition of 0.5% of nitrogen source to the mixture of thistle extract and malt extract showed excellent result among the conditions

7. As a result of sensory test of fermented thistle and non-fermented thistle syrup showed that there was no significant different in color, flavor and after taste, but fermented thistle syrup had higher preference of sourness than non-fermented thistle syrup and bitterness and astringency significantly decreased than non-fermented thistle syrup. From these result we confirmed that sensory properties were improved by fermentation.

8. In conclusion, condition of thistle extraction was suitable at 100℃ for 4 hours, Lactobacillus plantarum was selected as thistle fermentation bacteria and sugar add to improve fermentation effects of water extract of thistle was suitable condition of 12 °Brix using oligosaccharide. And through the experiment, we confirmed that cirsimaritin content and sensory characteristics of thistle extract could be increased by lactic acid fermentation.

목차 (Table of Contents)

• 서론 1
• 재료 및 방법 3
• 1. 실험재료 3
• 1.1. 원료 3
• 1.2. 미생물 3
• 2. 실험방법 4
• 2.1. 엉겅퀴 건조조건 시험 4
• 2.2. 엉겅퀴 열수추출 시험 4
• 2.3. 엉겅퀴 발효균주 및 발효조건시험 4
• 2.3.1. 발효 예비시험 4
• 2.3.2. 발효균주 선정시험 5
• 2.3.3. 엉겅퀴발효 당 첨가효과 5
• 2.4. Starter culture용 배지제조 시험 5
• 2.5. 발효엉겅퀴 시럽 제조 6
• 2.6. 이화학적 특성 분석 8
• 2.6.1. 수분함량 8
• 2.6.2. pH 8
• 2.6.3. 적정산도 8
• 2.6.4. 색도 8
• 2.7. 젖산균수 8
• 2.8. 항산화효과 8
• 2.8.1. Total phenolic content 8
• 2.8.2. Total flavonoid content 9
• 2.8.3. DPPH radical assay에 의한 scavenging activity 9
• 2.8.4. ABTS radical assay에 의한 scavenging activity 9
• 2.9. Cirsimarin 및 cirsimaritin 함량 10
• 2.10. 관능평가 11
• 결과 및 고찰 12
• 1. 엉겅퀴 건조온도에 따른 특성 12
• 1.1. 건조조건에 따른 수분함량 12
• 1.2. 건조조건에 따른 색도 13
• 2. 엉겅퀴 열수추출조건에 따른 항산화 특성 14
• 2.1. 열수추출조건에 따른 total phenolic content 14
• 2.2. 열수추출조건에 따른 total flavonoid content 15
• 2.3. 열수추출조건에 따른 DPPH radical scavenging activity 16
• 2.4. 열수추출조건에 따른 ABTS radical scavenging activity 17
• 3. 엉겅퀴 물 추출물 발효균주 선정 18
• 3.1. 발효 예비시험 18
• 3.1.1. pH 18
• 3.1.2. 적정산도 20
• 3.1.3. 젖산균수 22
• 3.1.4. Total phenolic content 24
• 3.1.5. Total flavonoid content 26
• 3.1.6. DPPH radical scavenging activity 28
• 3.2. 발효균주 선정 30
• 3.2.1. pH 30
• 3.2.2. 적정산도 31
• 3.2.3. 젖산균수 32
• 3.2.4. Total phenolic content 33
• 3.2.5. Total flavonoid content 34
• 3.2.6. Cirsimarin 및 cirsimaritin 함량 35
• 3.3. 엉겅퀴발효 당첨가 효과 37
• 3.3.1. pH 37
• 3.3.2. Total phenolic content 38
• 3.3.3. Total flavonoid content 39
• 3.3.4. Cirsimaritin 함량 40
• 4. Starter culture 제조를 위한 배지조성 41
• 4.1. 엉겅퀴추출액과 맥아즙 혼합비율에 따른 젖산균수 41
• 4.2. 탄소원 첨가에 따른 젖산균수 43
• 4.3. 질소원 첨가에 따른 젖산균수 44
• 5. 엉겅퀴발효시럽 제품평가 45
• 5.1. pH, 적정산도 및 색도 45
• 5.2. 항산화 효과 및 cirsimaritin 함량 46
• 5.3. 관능평가 47
• 참고문헌 49
• 요약 56