스팀 및 동결 전처리가 건조 감잎 열수추출물의 이화학적 특성에 미치는 영향

정헌식,윤광섭,김종국 한국식품저장유통학회 2023 한국식품저장유통학회지 Vol.30 No.6

This study was conducted to develop a preservation technology that can induce changes in physicochemical properties to effectively utilize of persimmon leaves. The application effects of steaming or freezing technique were investigated. Astringent persimmon leaves were steam-blanched (100℃, 30 sec) or frozen (-20℃, 15 d), followed by hot-air drying (50℃). The physicochemical properties of the extract obtained by hot-water leaching from the dried leaves were compared. The extract of leaves dried without pretreatment was used as a control. L* value was higher in steamed than in control and frozen. a* value was highest in the control. The browning index was higher in the frozen and lower in the steamed than in the control. Soluble solids were the highest in the steamed and the lowest in the frozen. Sucrose content was relatively high in the steamed, and the glucose and fructose contents were relatively high in the frozen. Total polyphenol content and DPPH radical scavenging activity were higher in steamed and lower in frozen than in control. Thus, it was confirmed that steam or freeze pretreatment after harvesting persimmon leaves affects the extraction yield, color, antioxidant capacity and component changes of dried persimmon leaves. Unlike steaming, freezing pretreatment showed the effect of promoting decomposition and browning reactions, and it is considered useful when such an effect is needed.

공자 칼, 남명 칼, 오늘의 패검명

정헌식 남명학연구원 2018 선비문화 Vol.34 No.-

유자 과피의 담금 조건이 침출주의 품질특성에 미치는 영향

정헌식,박한솔,김한수,이영근,성종환 한국식품저장유통학회 2019 한국식품저장유통학회지 Vol.26 No.2

This study was conducted to prepare liqueur using Citrus junos fruit peels. Effects of ethanol concentration (EC) and mixing ratio (MR) of leaching solvents with fruit peels on the quality characteristics of the liqueur were investigated. Sliced peels separated from C. junos with an MR of 25% were placed in glass jars and mixed with leaching solvents with ECs of 10%, 20%, 30%, 40%, or 50%. Additionally, sliced peels with MRs of 5%, 15%, 25%, 35%, or 45% were placed in glass jars, mixed with a leaching solvent with an EC of 30%, and then leached for 30 days at 20℃. As the EC increased, the soluble solid and vitamin C contents of the liqueur decreased slightly, while the phenolic compound content increased. The soluble solid content, titratable acidity, phenolic compound content, vitamin C content, antioxidant activity, and color properties (-a* value, b* value) increased linearly with increasing MR. From these results, it was confirmed that C. junos fruit peels could be used to produce liqueur. It was concluded that an MR of 45% or more was suitable for liqueur production.

Quality comparison of dried slices processed from whole persimmons treated with different deastringency methods

정헌식,김도희,김한수,이영근,성종환,윤광섭,문광덕 한국식품과학회 2017 Food Science and Biotechnology Vol.26 No.2

The effects of different deastringency treatments (untreated, carbon dioxide, warm water, or ethanol), before drying on the quality characteristics of dried fruit slices prepared from whole “Cheongdobansi” persimmons were evaluated. L* (lightness) and a* (redness) values of dried slices from warm water- and ethanol-treated groups were higher, respectively, compared to that of dried slices from other groups. Hardness was lower in dried slices from ethanol-treated fruits. Moisture, water activity, soluble solids, titratable acidity, and sensory properties (color, aroma, texture, sweetness, and overall acceptability) of the dried slices from astringency-removed fruits were higher when compared to those of the dried slices from non-treated persimmons. In particular, the dried slices from ethanol-treated fruits showed the highest values for these parameters. Moreover, soluble tannin and DPPH radical scavenging activity decreased by deastringency treatment. Results suggest that ethanol deastringency treatment before drying could be a useful method to improve most quality characteristics, except antioxidative activity, of dried persimmon slices.

Optimization of Roasting Conditions according to Antioxidant Activity and Sensory Quality of Coffee Brews

정헌식,김도희,윤광섭,이주백,문광덕 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.1

Response surface methodology (RSM) was used to determine the optimal roasting temperature and roasting time of coffee beans used for preparing brews with high antioxidant activity and sensory quality. Green coffee beans (Coffea arabica L. cv. Colombia Organic Tamata)were roasted at temperatures ranging from 140 to 220oC for 2-10 min and were then brewed with dripping hot water. The effects of the roasting conditions on the browning index, antioxidant activity, color, aroma, taste, and overall acceptability of the coffee brewed from the bean were investigated using a second-order central composite design. The quality indicators except the taste were significantly affected by roasting temperature and time, tending to increase and then decrease with increasing roasting temperature and time. Superimposed contour plots indicated that the optimal roasting temperature was 182oC and optimal roasting time was 7 min.

랫드의 출생전·후의 위조직 발달에 관한 형태학적 연구 1. 광학현미경적 및 주사전자현미경적 관찰

정헌식,김종섭,이종환,Chung, Heon-sik,Kim, Chong-sup,Lee, Joung-hwan 대한수의학회 1997 大韓獸醫學會誌 Vol.37 No.4

The present study was designed to investigate the morphological developments of the stomach in the prenatal and postnatal rats. The gastric fundus of 16- to 22-day-old fetuses, neonates, 7-day-old, 14-day-old, 21-day-old, and adult rats were observed by light and scanning electron microscopy. Light microscopic studies. 1. In the 16-day-old fetuses, the walls of the gastric fundus were differentiated into epithelium, lamina propria, muscle layer, and serosa. The lamina propria was composed of mesenchymal connective tissue cells with sparse nucleus and their fibers. 2. In the 17-day-old fetuses, the muscular layer were differentiated into the circular and longitudinal muscle layers. 3. The epithelium on the fundus of stomach was stratified columnar cells at 16-, 17- and 18-day-old fetuses, but partly converted into simple columnar epithelium at 19-day-old fetuses. 4. The mucous cells were positive by PAS reaction at the 19-day-old fetuses and then these developed rapidly within 1 or 2 days before birth. 5. In the 20-day -old fetuses, the parietal cells were distinguished from other type cells and these cells were chiefly crowded in the middle parts of the gastric glands after 7-day-old. Scanning electron microscopic studies. 6. The surface of gastric mucosa was covered with forms of the various protrusions by forming villi at the last few days before birth and these protrusion forms were fused and folded each other. 7. The mucosal surface was closely packed by polygonal mucous cells. The openings of gastric glands were seen as slit-like round invagination and were more numerous and increased gradually in depth after the postnatal life. The above findings indicate that prominent changes occurred in the pattern of cellular proliferation in the stomach fundus at the end of gestation. The gastric epithelium had well-defined glands composed of parietal, chief and mucous cells just before the birth. The stomach fundus, therefore, were developed morphologically as those of normal adult at fourteen days after birth.

Sprouting and Quality Control of Fresh Ginger Rhizomes by Modified Atmosphere Packaging with Film Perforation

정헌식,문광덕 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.3

The quality of ginger rhizomes packaged in low density polyethylene bags (modified atmosphere packaging - MAP) without perforations (P-0), with 2perforations (P-2), and 12 perforations (P-12) have been investigated for 5 months at 12±1^oC. Sprouting and rotting rates of ginger in P-2 and P-12 were lower than ginger in P-0. Weight loss was higher in P-12 than P-0 and P-2. Surface L^* (lightness) and a^* (redness) values in P-2 and P-12 were lower and higher, respectively, than those found for P-0. Sensory appearance and overall acceptability were rated significantly better in P-2 and P-12 than in P-0. Internal color, firmness, soluble solids, and pH of ginger in MAP were not affected by presence of perforations. Therefore, MAP with the appropriate number of perforations (in this work, 2 perforations) could be a useful method to control sprouting and maintain quality except for surface color of stored ginger rhizomes.

Changes in Color Parameters of Corn Kernels during Roasting

정헌식,김종국,문광덕,윤광섭 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.6

Changes in color parameters (L*, a*, b*, ΔE*,ho, and C* values) of corn during roasting were investigatedand subsequently described using mathematical models. Corn kernels were roasted for 50 min at 160, 180, 200,220, and 240oC. The L*, b*, ho, and C* values tended todecrease more rapidly as the roasting temperature and timeincreased up to 220oC and 50 min, whereas a* and ΔE*values tended to increase. Variation of L* and ΔE* valueswas found to be proportional to the roasting temperatureand time. Variation of L* value during roasting above180oC was adequately described by a first-order model. Cubic model satisfactorily described changes in all of colorparameters over the temperature range. Activation energiesof L* and ΔE* values were determined as 34.04 and 79.16kJ/mol, respectively. Results suggest that L* and ΔE*values may be used as color control indicators duringroasting of corn kernels.

초음파 추출이 커피 음료의 품질특성에 미치는 영향

정헌식,조정석,김한수,김동섭,이영근,성종환,문광덕 한국식품저장유통학회 2016 한국식품저장유통학회지 Vol.23 No.5

The effects of ultrasound-assisted extraction (UAE) on the physicochemical and sensory characteristics of coffee beverage were investigated. Coffee powder (4 g) was soaked into 80 mL distilled water and extracted for 15, 30, 60, 120, 180, 240, or 300 sec at 60℃ in an ultrasonic bath (40 kHz, 300 W). Hot-water extraction (HE) at 80℃ for 300 sec was used as a control. Content of soluble solids in coffee beverage prepared by UAE (60~300 sec) was same or higher than those of HE, however, no significant differences were observed among the four beverages extracted for more than 120 sec. Clarity and browning index of beverage prepared by UAE (15 sec) and by HE were significantly higher and lower, respectively, compared to those of the other. Content of phenolic compounds was lower and higher respectively, in beverage prepared by UAE (15 sec, 30 sec) and UAE (60~300 sec) than by HE. DPPH radical scavenging activity was highest in beverage prepared by UAE (15 sec) and HE. Sensory evaluation showed that color, aroma, taste, and overall acceptability were rated with the best score for beverage prepared by UAE (15 sec) and the worst score for beverage prepared UAE (120~300 sec). Therefore, ultrasound-assisted extraction can be used for improving quality of coffee beverage.

부추의 증숙처리가 착즙액 분무건조 분말의 품질에 미치는 영향

정헌식,김한수,김동섭,이영근,성종환 한국식품저장유통학회 2015 한국식품저장유통학회지 Vol.22 No.3

This study was conducted to develop a spray-dried garlic chives (Allium tuberosum) powder and to evaluate its quality characteristics depending on the treatment of steam blanching pretreatment (100℃, 3 min) and the addition of forming agents (dextrin (DE=10), β-cyclodextrin) during process. The steam blanching pretreatment showed an increase in L* value while a decrease in -a*, b*, C*, and h° values of the powder. Moisture content and water soluble index were not affected by the treatment of steam blanching and the addition of forming agents, whereas the particle diameter was the smallest in the steam blanching treatment and dextrin addition. Chlorophyll, phenolic compound, and vitamin C content, and DPPH radical scavenging activity of non-pretreated powder were significantly higher than those of the steam blanching treated powders. However, there was no significant difference between the two forming agents. The sensory acceptability (color, smell, and overall acceptability) of powder treated with steam blanching were significantly higher than those of non-pretreated powders. Therefore, the steam blanching pretreatment of fresh garlic chives affected on the better quality characteristics of the spray-dried powders when compared with non-pretreated powder though it adversely affected the natural chemical quality of fresh garlic chives.