ON SOME THETA CONSTANTS AND CLASS FIELDS

신동화 대한수학회 2014 대한수학회지 Vol.51 No.6

We first find a sufficient condition for a product of theta constants to be a Siegel modular function of a given even level. And, when K (2p) denotes the ray class field of K = Q(e 2πi/5 ) modulo 2p for an odd prime p, we describe a subfield of K (2p) generated by the special value of a certain theta constant by using Shimura’s reciprocity law.

여행수송위원회

신동화 한국식품과학회 2001 식품과학과 산업 Vol.34 No.2

여러 기관의 일반시험법에 의한 식용 타르색소의 규격 비교 시험

신동화,김용석,이영환,방정호,엄애선,신재욱,이달수,홍기형,박성관,최장덕 한국식품위생안전성학회 2004 한국식품위생안전성학회지 Vol.19 No.4

국내에서 유통되는 식용 타르색소 9종에 대하여 한국, 일본, 미국 및 JECFA의 색소시험법에 따라 비교·시험하였다. 식용색소의 물불용물 함량은 각 기관의 시험법에서 차이가 없었으며,모두 규격기준에 적합하였다. 식용색소 녹색제3호, 적색제3호, 청색제2호 및 황색제4호의 염화물 및 황산염 함량은 각 기관의 방법에 따라 약간 달랐지만 모두 규격기준에 적합하였고, JECFA와 미국방법에서는 분석하는데 시간이 더 많이 소요되었다. 비소 함량은 한국과 일본에서 비색법으로 비교하였으며, 규격기준이 미국 및 JECFA와 달랐다. 중금속 함량은 모두 규격기준에 적합하였으나 한국은 비색법 , 일본은 원자흡광도법, 미국과 JECFA는 두 가지 방법을 모두 사용하였다. 비술폰화방향족제 1급아민의 함량은 분석시료 모두 0.0005%(aniline으로서)이하로서 규격기준(0.01%이하)에 모두 적합하였다. An analytical method of nine synthetic food colors in Korea, Japan. Joint FAO/WHO Expert Committee of Food Additives (JECFA), and USA were compared. Contents of water insoluble matter in synthetic food colors tested were not different by general test methods of various organs. Contents of chloride and sulfate salts in Food Green No.3, Food Red No.3, Food Blue No 2, and Food Yellow No.4 slightly differed in various methods, and but up to the standard, and general test methods of JECFA and USA needed far more time. For the measurement of arsenic contents in food colors, colorimetric method in Korea and Japan, and silver diethyldithiocarbamate colorimetric method in USA and JECFA were used, but the standards of them were different. Content of heavy metals was up to the standard, but the methods were used colorimetric method in Korea, atomic absorption method in Japan, and both methods in JECFA and USA.

고추장의 지역별 제조방법과 품질특성

신동화,Sin, Dong-Hwa 한국식품연구원 1995 食品技術 Vol.8 No.4

식품위생 사건백서II

신동화,Sin, Dong-Hwa 한국과학기술단체총연합회 2005 과학과 기술 Vol.38 No.12

저장 유통중 시어진 된장의 화학적 성분 연구

신동화,강금성,이지영,정도연,한금수 한국식품위생안전성학회 2010 한국식품위생안전성학회지 Vol.25 No.4

Doenjang (fermented soybean paste) is one of the korean traditional fermented soybean product which is consumed with cooked rice as a soup or paste. During the fermentation, soybean protein hydrolyzed into amino acids and various peptide, and various organic acids by mirobes related and enzymes produced by meju fermentation. Some commercial products locationally samples give more sour taste than normal due to abnormal fermentation which the reasons are not clear. Three samples that gave sour taste organoleptically were collected and analyzed their characteristics such as pH, moisture content, acidity and microbial counts. The pH of the sour sample were lower than the normal with higher acidity as pH 5.39 (normal) to pH 4.36 (S2) and 15.80 ml of (0.1N NaOH consumed) to 21.80 ml (S1) respectively. Salt and moisture contents were different with sour and normal Doenjang as 16.38% (normal)to 8.92% (S3) in salt and 55.94% (normal) to 49.34% (S1) in moisture content. Total viable counts were 4.1 × 108(normal) to 8.0 × 105 (S2), and 3.4 × 108 (normal) to 8.0 × 105 (S2) in acid producing microbes at BCP plate. Yeast and mold were not detected. The composition of acids as mainly lactic acid and acetic acid of sour Doenjang. Total free amino acids content were lower the sour Doenjang than the normal.

집단급식소의 위생관리에 대한 실태 조사

신동화,소관순,김용석 한국식품위생안전성학회 2007 한국식품위생안전성학회지 Vol.22 No.1

survey on sanitary management at 98 food service institutions located in Jeollabuk-Do wereconducted. Food service institutions included 13 hospitals, 38 schools, 40 enterprises, and 7 others. The sterilizationin boiling water was used for disinfection of tableware, spoon and chopsticks, and dish towel. Cooking kit,refrigerator, chopping board, and knife were sterilized with disinfectant. Frequency of sanitary training program onemployees was 56.1% for 1 time/month, 12.2% for 2-3 times/month, and 11.3% for 1 time/week. Preparing ratio ofdefrosting, warehouse and rest room, and washing and sterilization diary were 73.8, 60.5, and 54.5%, respectively.However, checking ratio of environments (9.5%), personal sanitation (10.8%), and sanitary training program diary(8.4%) were low. Major obstacle factors on the introduction of Hazard analysis critical control point (HACCP)system into food service institutions were lack of equipment and facilities (54.1%) and lack of understanding anddata on HACCP system (17.3%). Therefore, in order to reduce the outbreak of food-borne diseases increasingperception on sanitary managements in food service institutions were needed.

건조동결 감자의 복원성에 미치는 건조조건의 영향

신동화,민병용,김정상,오상용 한국농화학회 1986 Applied Biological Chemistry (Appl Biol Chem) Vol.29 No.4

The relationship between weight reduction and rehydration of dehydrofrozen potato was determined. At initial stage of dehydration sliced potato lost moisture rapidly. After drying for 2 hours weight reduction of sliced potato was 56% for Superior var., and 55% for Irish Cobbler. The empirical drying equations sere obtained as follows: (M-M_e)/(M_o-M_e)=exp(-0.4487 θ^(1.2328)) and (M-M_e)/(M_e-M_o)=exp(-0.4951 θ^(1.1949)) for Irish Cobbler and Superior, respectively, where M_o, M_e, and M are dry base moisture content(%) of initial, equilibrium and at time θ in hour, respectively. With the decrease of weight above 50%, the rehydration rate decreased sharply and the color index L value also decreased while a and b increased. Lightness of dehydrofrozen potato decreased slightly and rehydration rate remained constant during storage at -18℃. The sulfite treatment led to increase of L value and decrease of a and b values.

Comparison of Boiling Point and Distillaiion Ranige, Melting Range, and Identification Methods of Various Organizations on Synthetic Food Additives

신동화,김용석,이영환,방정호,엄애선,신재욱,이달수,장영미,홍기형,박성관,권용관,박재석,Shin Dong-Hwa,Kim Yong-Suk,Lee Young-Hwan,Bang Jeong-Ho,Om Ae-Son,Shin Jae-Wook,Lee Tal-Soo,Jang Young-Mi,Hong Ki-Hyoung,Park Sung-Kwan,Kwon Yong-Kwan,P The Korean Society of Food Hygiene and Safety 2005 한국식품위생안전성학회지 Vol.20 No.3

식품첨가물공전의 일반시험법 중 비점 및 유분측정법, 융점측정법 및 확인시험법에 대하여 국내에 유통되는 식품 첨가물을 대상으로 한국, 일본, JECFA및 미국의 시험법에 따라 비교?분석하였다. 한국의 식품첨가물공전에서 비점을 측정하는 품목은 프로필렌글리콜 1품목이었고, 이 품목에 대하여 한국방법에서는 비점으로, 일본방법은 유분으로, JECFA와 미국방법은 증류가 일어나는 온도로 표시하도록 되어 있었으며, 측정결과 규격에 적합하였다. 유분측정법은 한국과 일본방법에서는 유분으로, JECFA와 미국방법에서는 증류온도로 표시하였다. 프로피온산의 유분은 4 기관의 규격에 모두 적합하였으며, 일본방법에는 이소프로필알콜에 대한 규격기준이 없었다. 응점측정법은 4 기관의 방법이 동일하였으며, 한국 식품첨가물공전에서는 28품목이 해당되었다. D-Mannitol의 경우 기관마다 규격기준이 약간 달랐으며, 미국방법에서는 L-ascorbic acid, calciferol 및 fumaric acid에 대한 규격이 설정되어 있지 않았다. 한국 식품첨가물공전에서 확인시험을 하는 화학적합성품은 251품목이었으며, 과망간산염, 글리세로인산염, 브롬산염, 치오황산염 및 브롬화물 등 5항목에 해당하는 개별품목은 없었다. 안식향산염 시험에서 안식향산칼슘은 가열해야 녹았으며, 구연산철은 한국과 일본방법 (2)에서 모두 구연산염의 확인이 불가능하였다. 암모늄염, 젖산염, 마그네슘염, 제이동염, 황산염, 인산염 및 아연염 시험법은 4기관에 모두 동일하였으며, 현행 시험법에 의해 모두 확인이 가능하였다. Boiling point and distillation range, melting range, and identification methods in general test method of Korea, Japan, Joint FAO/WHO Expert Committee of Food Additives (JECFA), and USA on chemical food additives were compared. Boiling point of propylene glycol was indicated as boiling point in Korea, distillate in Japan, distillation range in JECFA and USA, and its value was up to the standard. Distillation range of propionic acid was indicated as distillate in Korea and Japan, distillation range in JECFA and USA, and its value was up to the standard. There is no standard on distillation range of isopropyl alcohol in Japanese method. Test method of melting range on synthetic food additives was identical in all organizations, and there are 28 items to which this test method applies in Korean Food Additives Code. The standards on molting range of D-mannitol were different in various organizations, and in USA method there are no standards to which L-ascorbic acid, calciferol, and fumaric acid apply. Synthetic food additives performing the identification test were 251 items in Korean Food Additives Code, but there are no items to which manganese, glycerophosphate, bromate, thiosulfate, and bromide apply. Calcium benzoate was dissolved by heating in benzoate test and we could not identify the citrate in ferric citrate by method (2) of Korea and Japan. Identification test methods for ammonium, lactate, magnesium, copper, sulfate, phosphate, and zinc were identical in all organizations, and these could be identifed by current identification methods.

유과 제조의 기계화 연구

신동화,최웅,Shin, Dong-Hwa,Choi, Ung 한국식품과학회 1991 한국식품과학회지 Vol.23 No.2

유과제조시 가장 걸림돌이 되는 꽈리치기 공정과 반데기 제조공정의 연속공정화 및 표준화를 위하여 기존 chopper의 구조를 변경하고 conveyer를 연결하여 기계화 가능성을 시도하였다. Plate와 die를 새로 제작하여 실험한 결과 꽈리치기 및 반데기를 연속적으로 제조할 수 있었으며, 그 품질도 기존방법에 비하여 차이가 없었다. 반데기의 두께와 폭은 conveyer belt의 속도를 조절하므로써 가능하였으며, chopper에서 반죽의 토출량이 221.8g/sec($Slit\;:\;5{\times}50.5\;mm$)일 때 conveyer의 속도는 87.3 mm/sec가 바람직하였다. Chopper의 구성에서 knife나 plate의 모양 등은 꽈리치기 효과에 큰 영향을 주지 않았으며, 건조 후 반데기의 두께는 $3.0{\sim}3.5\;mm$인 경우 가장 좋은 유과품질을 얻었다. Chopper를 통과하는 횟수는 품질에 큰 영향을 주지 않으나 전연 꽈리치기 하지않은 경우 조직은 대단히 유약하였다. Whipping and bandaekee making process were known to a bottle neck for yukwa(deep-fat fried waxy rice snack) making process. For mechanization of the process, a machine was designed and manufactured with conveyer. Some functions of the machine were compared. The continuous whipping and bandaekee making machine was developed by modification of chopper. The chopper was substituted with specially designed plates and die. The newly designed plates were suitable for continuous whipping of dough and making bandaekee without showing any quality different at the final stage. The width and thickness of bandaekee could be controlled by speed of conveyer. The proper conveyer speed was 87.3 mm/sec when amount of extrudate of dough was 221.8 g/sec (MW 51%) from chopper. A shape of knife and plate among components of chopper was not seriously influenced on whipping effect. Expectable thickness of bandaekee for good quality was $3.0{\sim}3.5\;mm$. The number of passing through the chopper was not effected on yukwa quality·but no whipping showed bulky volume with too soft texture.