This study was conducted to find out the optimal solvent extraction method [Distilled water (DW), 70% ethanol, 99% ethanol] of mushrooms, including Pleurotus ostreatus (Jacq.) Que, Pleurotus eryngii and Flammulina velutipes and improve their usability as natural antioxidants. To analyze antioxidant activities in each mushroom, total polyphenol, flavonoid contents, 2,2-Diphenyl-1-picrylhydrazyl (DPPH), 2,2?-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) cation radical (ABTS+) and fluorescence recovery after photobleaching (FRAP) were measured. All mushrooms showed the highest total polyphenol contents in DW mushroom extract (p<0.001). Total flavonoid contents were the highest in P. eryngii and F. velutipes DW and 70% ethanol mushroom extracts (p<0.05). All mushrooms showed the highest activities using DPPH and FRAP assays in the DW extraction method (p<0.001). P. ostreatus (Jacq.) Que and P. eryngii showed the highest ABTS+ radical scavenging activity in the DW extraction method, and F. velutipes showed the highest activity in the 70% ethanol extraction method (p<0.001). As a result of comparing IC50 values of DPPH and ABTS+ radicals and FRAP EC50 values, the DW P. ostreatus (Jacq.) Que extract showed high antioxidant activities (p<0.001). Pearson's correlation between total polyphenol contents and antioxidant activities showed a positive correlation in all mushrooms (p<0.01). Therefore, extraction of the mushrooms with DW can enhance the extraction of effective bioactive substances and antioxidant activity.

This study investigated the quality characteristics of sweet pumpkin after blanching. Sweet pumpkins were blanched in distilled water, 2% citric acid and 2% NaCl water at 100oC for 3 min. The cooking loss of sweet pumpkin in the blanching groups was lower than that in the control group, and greenness and yellowness in the blanching groups were higher than those in the control group (p<0.001). Total polyphenol content (TPC) of sweet pumpkin increased after blanching (p<0.05), and TPC true retention (TR) was measured with the highest NB. CON and NB were significantly higher in ?- carotene content (p<0.001). Lutein content in the blanching treatment groups was lower than that in the control group, but NB was the highest between the blanching groups (p<0.001). DPPH and ABTS+ radical scavenging activity assays revealed higher antioxidant activity in the NB groups among the blanching groups (p<0.001). The CON was 2.44 log colonyforming unit (CFU)/ g in the total bacterial count, but there were no microorganisms in the blanching groups. In conclusion, blanching with the addition of 2% NaCl can inhibit the growth of microorganisms and improve TR and antioxidant activities in sweet pumpkin.

This study sought to investigate the effects of heat-moisture treatment (HMT) and ethanol treatment (EOH) for improving the quality and storage stability of Tteokbokki Tteok. The quality characteristics were evaluated by moisture, pH, color, texture profile analysis, and observing the microbial properties after the heat-moisture treatment or ethanol treatment. As the storage period increased, the moisture content of Tteokbokki Tteok tended to decrease except for the HMT group (p<0.05) while the pH did not show significant variation except for the EOH group (p<0.05). While measuring the color, the L-value tended to increase in all groups during the storage period. The a-value and the b-value showed the highest values in the HMT group and the control (CON) group, respectively. In the texture profile analysis, all groups showed a significant tendency to increase levels of hardness and chewiness as the storage period increased (p<0.05). The HMT group showed an increase in hardness and adhesiveness, which are characteristics of the HMT treatment. The results of examining the microbial properties of Tteokbokki Tteok showed that the total microbial count in the HMT group was 4.52 on the 8th day of storage, which was lower than the level in the CON group and the EOH group on the 4th day of storage. Yeast and mold were not measured during the storage period. Thus the results of this study showed that when manufacturing Tteokbokki Tteok, the heat-moisture treatment of rice powder increased the storage stability by delaying microbial growth and also had positive effects on quality.

The purpose of this study was to investigate the antioxidant activity and β-glucan content of extracts extracted by varying the temperature at 30, 55 and 80℃ after hot air drying or freeze drying of Pleurotus ostreatus and Pleurotus eryngii. For the analysis antioxidant activity of each mushroom, β-glucan, total phenol, flavonoid contents, and DPPH․ABTS+․Nitrite assay were measured. Also, the β-glucan content, total flavonoid content and ABTS+ scavenging activity increased with freeze drying rather than hot air drying, and increased with increasing extraction temperature in both mushrooms. However, the total phenol and nitrite scavenging activity increased with hot air drying rather than freeze drying, and decreased with increasing temperature in both mushrooms. DPPH scavenging activity was not significant in both mushrooms, but decreased with increasing extraction temperature. Pearson’s correlations between total flavonoid content and antioxidant activities were r=0.719~0.753 (p<0.01). As a result, the β-glucan content, total flavonoid content, and ABTS radical cation scavenging activity were highest during freeze drying and extraction at 80℃. And the highest total phenol content, DPPH radical scavenging activity and nitrite scavenging activity were obtained during hot air drying and extraction at 30℃.

콩을 사용하는 간장제조공정과 달리 쌀을 사용하여 쌀소스를 제조 후 품질특성 및 관능적 평가를 실시하였다. 35oC로 하여 120일 숙성시킨 쌀소스의 품질평가 및 관능적 특성 결과 수분함량은 55.08%로 나타났으며, 색도측정 결과 L값은 38.90, a값 -1.22, b값 5.74로 숙성기간이 증가 할수록 황색도가 높게 나타나 b값이 증가하였다. pH는 4.35로 나타나 숙성 기간이 증가할수록 pH가 감소하는 경향을 나타났으며 총 질소 함량 측정 결과 0.26%로 나타나 숙성기간이 길어질수록 쌀의 단백질을 분해시켜 총 질소 함량은 높게 나타났다. 관능평가 결과, 숙성기간 120일 처리구가 숙성기간 90일 처리구에 비해 색의 기호도는 낮게 평가되었으나, 맛과 향의 기호도에서 높게 평가되었다. 따라서 쌀소스를 제조하는 경우에 숙성온도를 35oC로 하여 120일 숙성시키는 것이 관능적 품질 측면에서 가장 적합할 것으로 보이며, 본 연구를 바탕으로 생산된 쌀소스는 조미 식품으로써 쌀의 이용가치를 부가할 것으로 사료된다.

Korean sliced rice cakes, or tteokguk, are conventionally dried and rehydrated during their preparation. In this study, the effects of the perforation process and various drying methods (e.g., hot-air drying, vacuum drying, low temperature drying, and freeze drying) on the quality characteristics of tteokguk (rice cake soup) were evaluated. In the experiment, the rehydration capacity and lightness increased as the pore number increased. The hardness, redness, and yellowness of tteokguk, in contrast, tended to decrease as perforations increased. The texture, taste, and overall acceptability scores of tteokguk increased as perforations increased. With respect to drying methods, the rehydration capacity was greatest for vacuum drying. The hardness of tteokguk was lowest for vacuum drying. The redness, yellowness, pH, and sensory characteristics did not differ significantly among tteokguk samples treated through various drying methods. These results suggest that high-quality ready-to-eat Korean sliced rice cakes could be created by perforation and vacuum drying.

The characteristics of extracts and precipitates after extraction at different water temperature (25, 50, 75, 95oC), ethanol ratio (25, 50, 75, 100%), and extraction method (stir, soak, autoclave) of yam powder and raw yam were investigated. The total polyphenol content was the highest in the 50% ethanol extract of yam powder. The DPPH radical scavenging activity was the highest in the 75% ethanol extraction and the crude saponin content was the highest in the 95oC water extraction. Tyrosinase inhibitory activity was the highest in 95oC water extraction, low concentration of ethanol extraction, and autoclave extraction. The peak viscosity, trough, and final viscosity of the precipitates increased after ethanol extraction, whereas decreased after the 95oC water extraction and the autoclave, indicating the destruction of starch granules. This was confirmed by observing the starch granules broken using the SEM. The significance of this study was to investigate the possibility of the use of yam resources as a material, processing product development, skin beauty functional food and cosmetic material.

This study was performed to determine the effects of different processing methods (AD: drying at 50°C for 15 h; ADR: roasting after drying; SAD: drying after steaming; SADR: roasting after steaming and drying) on the quality characteristics, total phenolic content, anthocyanin content, DPPH radical scavenging activity, and reducing powder of red radish (Bordeaux and watermelon radish) tea. The pH of red radish tea was the highest with SAD. In terms of the total sugar content, Bordeaux radish tea showed the highest level with AD, ADR, and SAD, and watermelon radish tea showed the highest level with SADR. The a value of Bordeaux radish tea was higher with AD and ADR. The b value of Bordeaux radish tea was increased with steaming and roasting treatment. In terms of measuring the colors of watermelon radish tea, the L value was decreased while the b value was increased with roasting treatment. The total phenolic content, DPPH radical scavenging activity, and reducing powder with ADR and SADR were higher than those in samples prepared by different processing methods. AD and SAD resulted in higher anthocyanin contents than ADR and SADR. In terms of sensory evaluation, the appearance and color were rated higher with AD and SAD, whereas the flavor and taste were ranked higher with ADR and SADR than in the other samples. The results suggest that red radish (Bordeaux and watermelon radish) tea prepared by ADR and SADR processing methods can be utilized as health functional tea material with antioxidant activity.

The purpose of this study was to determine the optimal mixing ratio of olive oil, parmesan cheese, and nuts for preparation of pesto with spinach. Based on a surface response methodology (RSM), the independent variables were olive oil (100~300 g), parmesan cheese (25~75 g) and nuts (12~36 g). The dependent variables were physico-chemical properties as pH, color values (L, a, and b values), viscosity and sensory evaluation. pH decreased with increasing parmesan cheese levels. The L value decreased and the a and b values increased with increasing olive oil levels. Viscosity was negatively correlated with olive oil levels but positively correlated with the amounts of parmesan cheese and nuts. The addition of oil exerted a positive effect on gloss, and oily taste. In the sensory evaluation, the values of appearance, color, flavor, taste and overall acceptance were in the range of 4.4~7.2, 3.7~7.4, 4.4~7.1, 3.9~7.3 and 3.5~7.6, respectively. The sensory evaluation results showed significant values in appearance (p<0.01), flavor (p<0.01), taste (p<0.01) and overall acceptance (p<0.05). The optimal amounts of spinach pesto with olive oil, parmesan cheese, and nuts were determined by numerical optimization of a canonical model and graphical optimization. The optimal amounts were 175.29 g of olive oil, 49.51 g parmesan cheese, and 27.37 g of nuts per 100 g of spinach.

The objective of this study was to increase starch extraction efficiency from domestic potato by five kinds of foodgrade cellulases (mixture of β-glucanases, pectinase, cellulase, hemicelullase, and β-glucosdiase). Cellulase-treated potato had a maximum of 40% higher starch extraction yield than non-enzyme treated potato. It turned out that the shape and structure of cellulose-treated and nonenzyme-treated potatoes were the same. The average particle size of cellulose-treated potato starch was smaller than non-enzyme treated potato. Interestingly, the small starch granular (<10 μm particle) was shown in extracted starch from cellulose-treated potato. Rapid viscosity analysis showed that starch from cellulase treated potato had lower pasting temperature than starch from nonenzyme-treated potato. The range of the gelatinization temperature (49-62oC) of starches from cellulose-treated potato was broader than that of starches from nonenzyme-treated potato. Therefore, the results of this study confirm that cellulase plays an important role in the extraction of starch from the potato and physicochemical characteristics of potato starch.

The purpose of this study was to investigate the ability of natural antioxidants as stabilizers for meat by-products to prevent lipid oxidation. The white internal organs were evaluated using different treatments: no antioxidant (control), ascorbic acid (T1), Artemisiacapillaris Thunb. (T2), Opuntia (T3), Schisandra chinensis (T4), and Saururuschinensis (Lour.) Baill (T5). Antioxidant activities were analyzed by measuring DPPH contents, superoxide anion radical levels, nitrate scavenging activities, and total polyphenol contents. T1 and T2 showed higher antioxidant activities and total polyphenol contents (p<0.05). Additionally, changes in physicochemical properties (pH, color, volatile basic nitrogen [VBN], and thiobarbituric acid reactive substances [TBARS]) and microbiological aspects in white internal organs processed with antioxidants were investigated. As storage time increased, the CIE a* and b* values of the white internal organs processed with natural antioxidants were decreased (p<0.05), and CIE L* values were low, particularly for the T3 sample relative to that in the control. Moreover, the pH, VBN, and TBARS values of samples T2–T5 were increased after 7 days of storage, but showed low values compared with those of the control (p<0.05). Moreover, compared with the control group, the treatments showed antimicrobial effects. Our results indicated that these natural antioxidants could be used as lipid oxidation stabilizers of meat by-products during storage and that Artemisiacapillaris Thunb. and Opuntia may have applications as natural antioxidants in the meat by-product industry.

본 연구에서는 열전소자와 플라즈마 장치를 삽입하여 제작된 컨테이너와 기존의 사용되고 있는 스티로폼(EPS)박스에 소고기를 저장하면서 저장 중 품질특성을 조사하였다. 온도변화 측정 결과 저장기간 동안 TCS-1 컨테이너가 2℃ 이하로 온도유지가 잘 되는 것으로 측정되었다. EPS박스는 저장 3일 이후 소고기가 부패되어 더 이상 실험이 불가능 하였다. 소고기의 신선도를 나타내는 휘발성염기질소(VBN)과 지방산패도(TBA)값의 측정 결과, 저장 7일째 TCS-1의 VBN은 7.72 mg%, TBA는 0.52 mgMA/kg, TCS-2의 VBN 값은 9.20 mg%, TBA는 0.91 mgMA/kg로 측정되어 TCS-1이 TCS-2 보다 유의적으로 적은 증가율을 나타내어 소고기의 신선도를 더 잘 유지하는 것으로 판단되었다. 미생물 변화는 저장 7일 TCS-1은 4.62 log CFU/g, TCS-2는 7.09 log CFU/g으로 측정되어 TCS-1이 유의적으로 미생물 증식 억제에 효과적인 것으로 나타났다. 기호도 조사 또한 저장 7일째 TEU-1은 모든 항목에서 6.5점 이상의 평가를 받았으나 TCS-2는 4.1 이하의 평가를 받아 소고기의 상품성이 상실된 것으로 판단되었다. 모든 분석항목에서 TCS-1이 TCS-2보다 소고기 신선도 유지에 효과적인 것으로 판단되었다.

For the distribution of fresh produce, the thermoelectric cooling system combined with thermo electric materials (TEM) and phase change material (PCM) was studied. The PCM used this study was produced by in-situ polymerization technology which referred microencapsulation of hydrocarbon (n-tetradecane and n-hexadecane). In this study, quality characteristics of bell peppers in thermoelectric cooling system combined with TEM and PCM were analyzed and control was placed in an EPS (expanded polystyrene) box. As a result of quality characteristics analysis, weight of bell peppers decreased and moisture content of bell peppers was 90.96~94.43% during storage. Vitamin C content of bell pepper decreased during storage and reduction ratio of control was higher than that of BPT-5 treatment(bell pepper in thermoelectric cooling system with PCM which is kept the temperature at 5℃). The result of color value, on 21 day, ΔE value of BPT-5 treatment was 5.05 while that of control was 41.8. On 21 day, total bacteria count of BPT-5 treated bell pepper shown less than that of control. In conclusion, it suggested that the thermoelectric cooling system combined with PCM improved quality of fresh produce during transportation and storage.