식용곤충인 갈색거저리 유충이 식품 대체원료로써 식육에 대한 대체 가능성을 타진하고자 갈색거저리 유충 분말을 대체하지 않은 제품을 대조구로 설정하고 1%, 2%, 3% 비율로 대체한 유화소시지를 처리구로 하여 4±1℃에서 1, 8, 15, 22, 29일간 저장하면서 이화학적 특성과 관능적 특성 변화를 측정하였다. 갈색거저리 유충 분말을 첨가한 처리구의 pH는 대조구보다 증가하였고, 보수성(WHC)은 저장기간에 따라 대조구와 처리구 간 유의적인 차이는 크게 나타나지 않았으나, 대체량이 많을수록 보수성이 더 우수하였다(p<0.05). 휘발성 염기태질소(VBN), 지방산패도(TBARS) 는 대조구보다 감소하였으며, 관능검사의 경우 대조구와 유의적 차이가 나타나지 않았다(p<0.05). 따라서, 처리구가 대조구보다 우수한 품질과 저장성을 가지고 있었으며, 기호적인 측면에서도 뒤처지지 않아서 갈색거저리 유충 분말로 식육을 대체하는 것이 가능하다고 판단되어 식용곤충을 식품 대체원료로 제품화하였을 때, 식용곤충에 대한 거부감을 완화하고 소비자들에게 있어 긍정적인 인식의 변화를 이끌어낼 수 있는 기초자료를 제시할 수 있었다.
We conducted an on-site application study at the livestock cooperative fertilizer plant to compare the composting period, temperature change, moisture content, and chemical properties between livestock manure compost using sawdust as a moisture regulator with those using spent oyster mushroom substrate. The composting period, moisture content, and fertilizer composition of compost containing spent oyster mushroom substrate did not differ from that of conventional compost mixed with sawdust after the first and second fermentation and post-maturation stages, it was suitable as a material for manufacturing livestock manure compost. The spent oyster mushroom substrate also lower the production cost of livestock manure compost by replacing the more expensive sawdust. The developed technology is expected to contribute towards the utilization of by-products of the oyster mushroom harvest while simultaneously producing high quality livestock manure compost.
This study was conducted to compare the quality characteristics of commercial tofu products from the market in Korea. Seventeen types of commercial tofu samples were taken and their physicochemical properties, including soluble solid contents, salinity, pH, total acidity and moisture (total solid contents), were analyzed. The hardness of tofu was negatively correlated with the moisture contents of tofu (r=-0.667**). The commercial tofu showed pH 5.80~6.24, total acidity of 0.016~0.034%, soluble solids of 1.50~3.45 °Brix, salinity of 1.20~2.30%, and moisture content of 79.91~87.57%, respectively. All 17 tofu samples sold in the Korean market were prepared using crude MgCl2 and sea water as a coagulant. The quality characteristics vary depending on the constituent’s of soybeans, and the ratio and amount of coagulants of tofu used. The origin of soybean seeds affected the yellowness of tofu; tofu made from imported soybean showed a higher b value than domestic soybean. These results are expected to be useful for understanding trends in the domestic tofu industry.
본 연구는 기능성 물질인 알로에를 종류별로 첨가함에 따라 유화소시지의 이화학적 특성과 저장성, 그리고 관능성에 미치는 영향을 조사하기 위해 수행되었다. 알로에 베라(AV구)와 알로에 사포나리아(AS구)는 각 3%씩 첨가하였으며, 모든 처리구들은 냉장온도 4±1℃에서 4주간 저장하면서 주 1회 간격으로 실험이 진행되었다. pH는 AV구와 AS구가 대조구보다 유의적(p<0.05)으로 낮았고, 저장기간의 경과함에 따라 대조구 및 모든 처리구는 증가하였다. 보수성에서 AS구는 대조구와 AV구보다 유의적(p<0.05)으로 높은 값을 나타냈으며, 저장기간의 경과함에 따라 대조구 및 모든 처리구는 유의적(p<0.05)으로 감소하였다. 적색도는 AS구가 대조구 및 AV구 보다 낮은 값을 나타내었고, 황색도는 AS구가 대조구, AV구보다 높은 값을 나타내었다. 전단가는 AS구가 대조구보다 낮은 값을 나타냈으며, AV구와는 유의적인 차이가 없었다. 지방 산패도에서 AS구는 유의적 (p<0.05)으로 가장 낮은 값을 나타내었고, 관능 평가의 색은 AV구가 가장 높은 값을 나타냈으며, 선호도는 AV구가 대조구보다 높은 값을 나타냈고 AS구와는 유의적인 차이가 없었다. 이는 알로에 사포나리아의 첨가가 높은 보수성, 알로에 베라 첨가보다 낮은 지방산패도, 유사한 관능성을 나타내 기능성 소시지의 개발에 충분한 경쟁력을 가지고 있으며 향후 알로에 사포나리아를 첨가한 육제품의 일반화 및 대량생산 체계의 확립에 긍정적인 영향을 준다고 판단된다.
This study investigated the effect of the addition of various levels of pig head meat (HM) as a substitute for rear leg meat (RLM) on the physico-chemical quality characteristics of non-emulsified, smoked, and cooked sausage during refrigerated storage. Sausages were prepared in four variations according to the proportion (0%, 10%, 20%, or 30%) of HM added and maintained at 4°C. Quality measurements were taken for 28 days. The sausages added with the addition of 20% and 30% HM had significantly (p<0.05) higher moisture and lower protein content compared to those without the addition of HM. The pH value during the storage period was higher (p<0.05) in the sausages to which the HM had been added than in those without HM. The sausages with 30% HM showed the lowest (p<0.05) L* and b* values and the highest (p<0.05) a* value during the storage period. The 2-thiobarbituric acid reactive substances (TBARS) content, hardness, cohesiveness, springiness, gumminess, and chewiness of the sausages showed no significant variations with the addition of various levels of HM. These data suggest that RLM could be substituted with 30% HM because it does not negatively affect the quality of the non-emulsified sausage. However, a further study on sausages made with 100% HM instead of RLM may be needed to improve its utilization.
국제해사기구(IMO)의 황함유량 규제에 따르는 저유황연료유는 생산 공정에 따라 다양한 물리화학적 특성을 가지게 된다. 본 연구는 저유황연료유 및 저유황-고유황 혼합연료유의 물리화학적 특성연구 결과를 해양오염 방제대응의 기초자료로 활용하고자 한다. 연구에 사용된 혼합연료유는 황함유량이 0.46 mass%인 저유황연료유와 0.36 mass%인 저유황연료유에 고유황연료유를 25, 50, 75 mass% 혼합하여 제조하였다. 이 혼합연료유에 대해 동점도, 유동점 및 Saturates, Aromatics, Resins, Asphaltenes(SARA)분포 등 물리화학적 특성에 대해 실험실 연구를 하였다. 동점도가 높고 유동점이 낮은 특징의 고유황연료유가 75 mass% 혼합함에 따라, 혼합연료유의 동점도는 350.2 %까지 증가 하였으며, 유동점이 23℃와 -11℃의 저유황연료유는 각각 -3℃ 및 -6℃까지 유동점이 내려가거나 올라갔다. Asphaltenes 분포가 적은 저유황연료유에 고유황연료유를 혼합함에 따라, Saturates분포는 68.8 %까지 감소하고, Asphaltenes분포는 1,417 %까지 크게 증가하였다.
Chungyuk-jang is one of korean traditional soy food made by boiling with meat, seafood and soybean which is fermented after roasting. To investigate the difference in the physicochemical characteristics of the Chungyuk-jang fermented with roasted soybean in different conditions, Chungyuk-jang was made from soybean roasted on the three condition, 140oC for 21 min (CY140), 180oC 9.5 min (CY180), 220oC 6 min (CY220) which was decided by pre-test and compared to one made without roasting (CY0). The moisture of Chungyuk-jang was 79.98~81.87% and pH was 6.15~6.25. The lightness and yellowness of CY0 was higher than Chungyuk-jang made of roasted bean whereas redness and brown pigment was the highest on CY220. The contents of free sugar of CY140 was the highest among the treatment. The contents of amino-N of Chungyuk-jang (CY140, CY190, CY220) was higher significantly than CY0. The contents of total free amino acid and glutamic acid was highest on fermented soybean roasted for 140oC, 21 min (CY140) and followed by fermented soybean roasted on 180oC 9.5 min (CY180), 220oC 6 min (CY220) and CY0 (without roasting).
This study was conducted to investigate the effect of dietary total mixed ration (TMR) supplementation and dry-aging period on the physico-chemical and sensory quality of striploin (longissimus lumborum) from multiparous Hanwoo cows. The experimental cows were divided into two treatments (n=3/treatment) according to the type of feed: in one treatment (slaughter age: 87±6 months old, parity: 5±1) the cows were fed on TMR for 7 months before slaughter, while in the other treatment (slaughter age: 83±9 months old, parity: 5±2) the cows were fed on concentrate and rice straw (CRS) for the whole rearing period. After slaughtering, the striploins were dry-aged for 20 or 40 days at 2±1℃, 85% relative humidity and 2 m/sec air flow velocity and then utilized for quality measurements. The pH value, cooking loss, and hypoxanthine content were higher (p<0.05) for the striploins dry-aged for 40 days than for those dry-aged for 20 days. Notably, the inosine 5’-monophosphate content was decreased (p<0.05) by increasing the dry-aging time. With regard to microbiological quality, the striploins dry-aged for 40 days exhibited lower (p<0.05) lactic acid bacteria counts and higher (p<0.05) coliform counts than those dry-aged for 20 days. Moreover, the tenderness and overall liking scores based on sensory evaluation were higher (p<0.05) for the dry-aged striploins of the TMR treatment and those dry-aged for 40 days than for the CRS treatment and those dry-aged 20 days, respectively. These findings suggest that dietary TMR supplementation leads to an increase in the sensory preference of dry-aged striploins from multiparous Hanwoo cows, and alteration of the CRS into the TMR may improve the quality of dry-aged Hanwoo beef.
본 연구는 성별에 따른 2등급 한우의 소분할 부위별 보수력, 가열감량, 전단력 및 관능 특성을 조사하고자 실시하였다. 한우 15두(암소 5두, 수소 5두 및 거세우 5두)를 도축한 다음 등급 판정을 한 후 39개 소분할 부위를 발골하여 육질 특성을 조사하였다. 2등급 한우의 소분할 부위별 보수력은 46.97~63.16%를 나타내었으며, 가열감량은 52.44~71.58%로 안심살과 꽃등심살 부위를 제외한 부위에서 유의적인 차이가 나타나지 않았다(p>0.05). 전단력은 2.36~6.80 kg/cm2으로 암소의 안심살, 윗등심살, 꽃등심살, 아래등심살, 부채살, 앞다리살, 갈비덧살, 삼각살, 업진살, 꽃갈비 부위에서 수소와 거세우에 비해 낮은 전단력을 나타내었으며(p<0.05), 거세우의 살치살, 꾸리살, 부채덮개살, 우둔살, 설깃살, 설깃머리살, 도가니살, 양지머리, 차돌박이, 뒷사태, 안창살 부위는 수소와 암소에 비해 낮은 전단력을 나타내었다(p<0.05). 풍미는 윗등심살, 아래등심살, 홍두깨 살, 보섭살, 양지머리 및 차돌박이 부위에서 수소가 암소와 거세우에 비해 낮은 점수를 받았으며, 나머지 부위에서 유의적인 차이가 나타나지 않았다(p>0.05). 저작감은 암소의 아래등심살, 채끝살, 목심살, 꾸리살, 부채살, 설깃머리살 및 차돌박이 부위에서 수소와 거세우에 비해 높은 점수를 받았으며(p<0.05), 거세우의 치마살 및 뭉치사태 부위가 암소와 수소에 비해 높은 점수를 받았다(p<0.05). 종합적인 기호도는 암소의 채끝살, 꾸리살 및 부채살 부위가 수소와 거세우에 비해 높은 점수를 받았으며(p<0.05), 거세우의 윗등심살, 살치살, 앞다리살, 치마살 및 앞치마살 부위가 암소와 수소에 비해 높은 점수를 받았다(p<0.05). 2등급 한우고기는 수소가 암소와 거세우에 비해 높은 보수력을 나타내었으며, 암소와 거세우가 수소보다 낮은 전단력을 나타내었으며, 풍미에서 높은 점수를 받은 거세우의 부위와 저작감에서 높은 점수를 받은 암소의 부위는 종합적인 기호도에서 도 높은 점수를 받았다.
PURPOSES : Asphalt pavements are damaged by various causes, such as cracks, potholes due to climate, and traffic environment. Asphalt aging has a significant effect on cracks, which may also form potholes. The purposes of this study are to estimate the change in asphalt binder and mixture performance and to correlate the physicochemical changes of the asphalt binder and mixture performance with aging.
METHODS : The aging process of the asphalt was determined in the laboratory, based on the methods used in previous studies. In terms of consistency (stiffness), crack-resistance performance, moisture susceptibility, SK investigated the binder part, and Shoreki investigated the mixture part depending on the aging time.
RESULTS : The consistency (stiffness) and brittleness of both the asphalt binder and mixture tended to increase with aging. In particular, the crack-resistance performance of the asphalt binder (G*sinδ, ductility, and ΔTc) and mixture (flexural fatigue test and Cantabro test) deteriorated because of asphalt aging. Furthermore, the aging mechanisms (oxidation and polymerization) were identified based on the chemical structure analysis.
CONCLUSIONS : It is confirmed that the aging affected the chemical composition change and the physical properties of the asphalt. Asphalt pavements are significantly affected by the aging characteristics of the binder. It is concluded that the crack-resistance performance of the mixture decreases with aging due to these physical and chemical changes.
The physicochemical characteristics of oyster mushrooms (Pleurotus ostreatus) cultivated using liquid spawn (MLS) were compared with those of commercial mushrooms cultivated using solid spawn. The color intensity of the two types of mushrooms showed no remarkable difference. The hardness of the MLS-cultivated mushrooms was significantly higher, but their moisture content (86.80%) was significantly lower than that of the commercial mushrooms. Mineral contents in MLS-cultivated mushrooms (421.17 mg/100 g) were significantly higher than those in the commercial mushrooms (333.26–362.78 mg/100 g); in particular, the potassium (K) content was the most abundant in the former. The amino acid content in the MLS-cultivated mushrooms (4,695.22 mg/100 g) was about 1.4–2.0 times that in the commercial mushrooms. The essential amino acid contents and sum of aspartic acid and glutamic acid were higher in the MLS-cultivated mushrooms than in the commercial mushrooms. The β-glucan content in the MLS-cultivated mushrooms was 1.1–2.3 times higher than that in the commercial mushrooms. The total phenol and flavonoid contents and the DPPH and ABTS radical-scavenging activities of the MLS-cultivated mushrooms were significantly higher than those of the commercial mushrooms; however, the reducing power showed an opposite trend. Therefore, MLS-cultivated mushrooms contained higher amounts of valuable components and higher antioxidant activities than commercial mushrooms.
본 연구는 아질산나트륨 및 비타민 C의 대체로 첨가한 수벌번데기 분말이 유화형 소시지의 이화학적 품질 특성에 미치는 영향을 구명하고자 하였다. 시료는 아질산염, 비타민 C 및 수벌번데기 분말의 첨가 수준에 따라 각각 아질산나트륨 150 ppm+비타민 C 200 ppm(대조구), 아질산나트륨 75 ppm+ 비타민C 100 ppm+수벌번데기 분말 6.015%(T1) 또는 수벌번데기 분말 12.03%(T2)을 첨가하여 제조한 후 4℃에 30일 동안 저장하였다. pH는 수벌번데기 분말의 첨가 수준이 증가함에 따라 현저하게 감소하였다(p<0.05). 일반성분 함량은 수벌번데기 분말의 첨가 수준이 높은 소시지에서 낮은 수분 및 조단백질 함량과 높은 조지방 및 조회분 함량을 보였다 (p<0.05). 지방산 조성은 T1과 T2가 대조구에 비해 포화지방산 함량이 높았으나(p<0.05), 불포화지방산 및 다가불포화지 방산 함량은 낮았다(p<0.05). 색깔은 T1과 T2가 대조구보다 현저하게 낮은 명도(L*) 및 적색도(a*)와 높은 황색도(b*) 및 hue-angle(h°)을 보였으며(p<0.05), T2의 경우 가장 낮은 chroma(C*)를 나타내었다(p<0.05). 지방산화물(TBARS) 함량은 T2가 가장 높았으며(p<0.05), 특히, 대조구보다 2배 이상 높았다. 조직감은 T1과 T2가 저장기간 동안 대조구에 비해 단단한 특성을 보였다(p<0.05). 따라서 유화형 소시지에서 수벌번데기 분말의 첨가는 색깔, 지방산화안정성 및 조직감에 부정적인 영향을 미치는 것으로 나타나, 아질산나트륨 및 비타민 C 대체 효과가 없었다