초록 ▼

1) 단일 장치내에서 떡을 제조할 수 있는 주요 부품의 기능분석 및 구조 정립
ㆍ 기존 제조공정의 해석 및 최적조건 적출
ㆍ 단위공정의 extrusion화를 위한 부품기능 및 구조적출
ㆍ Screw elements 및 heating/cooling barrel 구조 설계 및 제작
ㆍ 실험규모 장치시작 및 시제품 생산시험
2) 실험규모 장치를 이용한 시제 떡제품의 물성개선연구,
ㆍ 부재료(유화제, 타 곡물전분)의 배합비율, extrusion parameter 조합 등의 실험설계
ㆍ 생산 떡의 조직

1) 단일 장치내에서 떡을 제조할 수 있는 주요 부품의 기능분석 및 구조 정립
ㆍ 기존 제조공정의 해석 및 최적조건 적출
ㆍ 단위공정의 extrusion화를 위한 부품기능 및 구조적출
ㆍ Screw elements 및 heating/cooling barrel 구조 설계 및 제작
ㆍ 실험규모 장치시작 및 시제품 생산시험
2) 실험규모 장치를 이용한 시제 떡제품의 물성개선연구,
ㆍ 부재료(유화제, 타 곡물전분)의 배합비율, extrusion parameter 조합 등의 실험설계
ㆍ 생산 떡의 조직 및 조리 특성 개선을 위한 최적 조건 확립 2) 시작장치의 구조개선 및 scale -up 연구 Lab, scale 장치(시간당 50-100 kg 생산능력)의 생산규모를 시간당 300-1000 kg의 생산 능력을 갖는 장치로 scale-up을 위한 technical/engineering 자료를 적출하여 생산장치의 사양결정
3) 주변장치 (자동제어 System 포함) 사양결정 및 생산체계확립
ㆍ 장치의 PID controll을 위한 Data acquisition 및 relay controller 구축
ㆍ 압출 떡의 절단, 건조 장치 사양 결정

Abstract ▼

Rice cake is called "Ga-Rae-Dduk" have been used as the staple dish at New Years Day in Korea. The rice cake was produced by small manufacturer scattered all around the nation by using 7,000 metric ton of rice as raw material in 1995.
The conventional process for producing rice cake involves a se

Rice cake is called "Ga-Rae-Dduk" have been used as the staple dish at New Years Day in Korea. The rice cake was produced by small manufacturer scattered all around the nation by using 7,000 metric ton of rice as raw material in 1995.
The conventional process for producing rice cake involves a series of complex stages, such as washing and cleaning the rice, wet-milling into the fine flour, steaming the flour to gelatinize, kneading and extruding the batter under pressure through a shaping die, cutting, cooling and packaging. The manufactures have been faced with the modernization of the processing method in order to save labor cost and to reduce waste water.
Extrusion cooking is a more effecient method for producing rice cake than the convetional method. It would be more attractive if the rice could be used directry as the raw material instead of powder from. Thus an extruder combining the four stages of milling, cooking, kneading and forming could save labor and make the process automated.
The effect of milling methods on the physicochemical properties of extruded Ga-Rae-Dduk was evaluated on the aspect of proximate compositions, particle size distribution, degree of gelatinization, rheological property, storage stability, extractable solid, cooking time, water absorption index(WAI), and change of hardness after cooking. The manufacturing method of Ga-Rae-Dduk included; 1) CON: Ga-Rae-Dduk prepared by the conventional method of rice miller, 2) DE1: extruded Ga-Rae-Dduk at low screw-speed using rice flours prepared by dry grinding, 3) DE2: extruded Ga-Rae-Dduk at high screw-speed using rice flours prepared by dry grinding, 4) WE1: extruded Ga-Rae-Dduk at low screw-speed using rice flours prepared by wet grinding, and 5) WE2: extruded Ga-Rae-Dduk at high screw-speed using rice flours prepared by wet grinding,
The rice flours of particle size distribution revealed 294.9 μm, 329.3 μm for rice flours prepared by dry grinding, rice flours prepared by wet grinding.
The moisture content of Ga-Rae-Dduk revealed 46.7, 38.9, 39.3, 38.7 and 39.5％ for CON, DE1, DE2, WE1, and WE2, respectively.
CON showed a significantly higher (p<0.05) degree of gelatinization (89.6％) than other while those of DE1 and WE1 remained lowest (73.8％, each) after extrusion. The apparent viscosity of Ga-Rae-Dduk paste was increased by raising the screw speed of the extruder.
The hardness of Ga-Rae-Dduk stored at 5℃ increased gradually and then showed a sharp rise after 15 hr. Generally, more extent of increase was noted from WE1 and WE2 in contrast with DE1 and DE2. At 25℃, negligible change of hardness was observed from CON while all the extruded samples (DE1, DE2, WE1, and WE2) became ten times as hard as 0 time storage samples. In contrast, significantly higher increases of hardness were noted from DE1 and DE2 as compared with WE1 and WE2 (p<0.05).
A relatively higer amount of solid from Ga-Rae-Dduk was extracted into water with boiling time in DE1 and DE2 while the amount was significantly lower in WE1 and WE2 (P<0.05).
The WAI value and related increase of softness in boiling water were significantly higer in DE1 and DE2 than WE1 and WE2 (p<0.05). The overall quality parameters were mostly influenced by screw speed of the extruder and more favorable result was brought from the higher screw speeds. With respect to milling methods, drying milling caused higer amounts of damaged starch and the subordinating increases in extractable solids, WAI, and hardness of Ga-Rae-Dduk. A cooking (boiling) time of four to six minutes was most appropriate to recover the initial softness of the Ga-Rae-Dduk pieces.

목차 Contents

• 표지...1
• 제출문...2
• 요약문...4
• SUMMARY...10
• 목차...14
• 제 1 장 서 론...16
• 제 1 절 연구개발의 목적과 범위...18
• 제 2 절 연구 내용...19
• 제 2 장 기존 공정 분석 및 필요 부품 시작 및 성능시험...20
• 제 1 절 기존공장 조사 및 공학적해석...20
• 1. 국내 쌀 떡가공공장 현황...20
• 2. 가공공정의 공학적 해석...20
• 제 2 절 떡 제조용 압출성형기 구성 및 시험생산...22
• 1. 가래 떡 제조용 부품 설계 및 제작...22
• 가. 분쇄기능 screw elements...22
• 나. 냉각 또는 가열 기능을 갖는 barrel...23
• 다. 성형 die 및 bleaker plate제작...23
• 2. 제작 부품별 성능시험...26
• 가. 전처리(수세 및 침지) 공정 개선...26
• 나. 분쇄성능 시험...26
• 다. 떡 제조 실험 및 특성분석...31
• 제 3 장 Scale-up 방안제시 및 자동차 및 주변기기 구성...60
• 제 1 절 Scale-Up...60
• 1. 문헌 및 이론적적 고찰...60
• 2. lab. extruder의 screw 및 barrel 구조 분석...67
• 3. 가래떡 제조중 형태별 투입에너지의 측정...71
• 제 2 절 Process 및 Sys tem parameter의 자동기록...73
• 1. 측정장치 구성...73
• 2. 신호전환 및 display...73
• 3. Mornitoring 결과...75
• 제 3 절 주변기기 사양 결정...76
• 1. 압출 떡의 절단 및 냉각...76
• 2. 건조 떡 건조기 사양...76
• 참고문헌...77