• Title/Summary/Keyword: physicochemical traits

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Effect of Germination Condition and Drying Methods on Physicochemical Properties of Sprouted Brown Rice (발아조건 및 건조방법이 발아현미의 이화학적 특성에 미치는 영향)

  • 김선림;손영구;손종록;허한순
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.46 no.3
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    • pp.221-228
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    • 2001
  • This study was carried out to investigate the effect of germination condition and drying temperature on growth and physicochemical properties of brown rice. Three brown rice seeds of Ilpumbyeo, Dasanbyeo and Heugjinjubyeo were stored at room temperature for six weeks to test the time-sequence germination viability. Relatively stable germination ratio was maintained until 2 weeks after storage. However, 3 weeks after storage, germination ratio of brown rice seeds started to decrease rapidly and their germination ratio was lower than 80%. For this reason, brown rice was recommended for seeding within 2 weeks after hulling. During the initial 5 days, germination ratio of 24 hours pre-soaking brown rice was higher about 2-3% than that of non-soaking brown rice. The $25^{\circ}C$ was considered as the most favorable temperature for brown rice germination, because of the high germination ratio and desirable coleoptile growth of the brown rice, and little seed rotting symptoms. The scanning electron micrographs showed the structural differences between hot-air dried and freeze dried germinated-brown rice kernel. In the freeze dried germinated-brown rice, seed coat (pericarp, tegmen and aleurone layer) was mechanically disrupted from the endosperm, and many cleavages were observed among starch storing cells and starch granules. The endosperm of freeze-dried brown rice kernels formed the sponge-like structures and showed the fragile traits. For this reason, hot-air drying is considered as more suitable method than freeze drying for germinated-brown rice. The crude protein and amylose contents were slightly changed, but there were no significant differences during the germination period. Crude fiber content was decreased, but crude Int and total amino acid contents were increased as seeding days increased. A rapid increase in $\alpha$-amylase activities of germinating brown rice was observed at S days after seeding, and $\alpha$-amylase activities were decreased from 8 days after seeding. Total free sugar contents were decreased during the germination period. There was continuous decline in the contents of sucrose and glucose until 8 days after seeding, but fructose and maltose content were gradually increased from the 5 days after seeding.

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Varietal Variation in Structure and Physical Characteristics of Rice Endosperm Strach (쌀 배유전분구조 및 물리적 특성의 품종 변이)

  • 강미영;최해춘
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.38 no.6
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    • pp.513-523
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    • 1993
  • Varietal difference in structural and physical characteristics of rice starch and interrelationships between these starch properties and the physicochemical components of rice grains were investigated for twenty four rice varieties, which were considerably different in amylose content, gelatinization temperature and gel consistency, to obtain the basic informations for diversifying the utility of rice grains and for developing various rice cultivars adaptable to rice food processing. Wave length of maximum absorbance for blue color reaction of starch-I$_2$ complex was 520nm for glutinous rice and 560~600nm for nonglutinous rice. The higher amylose rice showed the longer wave length but there was considerable difference of the wave length among rice materials with similar amylose content. Varietal difference in frequency distribution of debranched starch molecules by isoamylase hydrolysis was largest in amylose fraction, the longest fraction(Fr. I), and was next bigger in intermediate fraction(Int.Fr.) and the ratio between short and long glucose chain of amylopectin fraction(Fr. III /Fr. II). The Fr. III / Fr II ratio was higher in glutinous rice than in nonglutinous one but it was considerably different among nonglutinous rice varieties without any connection with amylose content. The lower alkali digestible rice showed the longer half-hydrolysis time in acid solution. Both soft and hard gel rice varieties in gel consistency test revealed significant varietal difference of 50% acid hydrolysis time. The harder rice in gel consistency exhibited the less frequency of short branch fraction of amylopectin (Fr. III) and the higher amylose content. Twenty four rice varieties were cleary classified by upper two principal components contracted from structural or physical traits of rice starch and some physicochemical properties of rice grain by principal component analysis. The 1st and 2nd principal components can be characterized to components related with amylose and amylopectin structure respectively.

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Production of Mozzarella Cheese Analogue by Ultrafiltration (한외여과를 이용한 Mozzarella Cheese Analogue 제조에 관한 연구)

  • Lee, Sung-Hui;Song, Kwang-Young;Seo, Kun-Ho;Yoon, Yoh-Chang
    • Journal of Dairy Science and Biotechnology
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    • v.31 no.1
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    • pp.21-33
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    • 2013
  • The purpose of this study was to improve the production of Mozzarella cheese analogues manufactured using mixtures of soy milk and concentrated raw milk by performing ultrafiltration (UF) and to assess the quality of these cheeses during a 30-day storage period at $4^{\circ}C$, relative to that of Mozzarella cheese manufactured with the traditional method. The solid consistency of Mozzarella cheese analogue prepared from milk mixtures was lower than that of cheese manufactured from raw milk or soy milk and increased during storage, which is considered to be the result of decreasing water levels, as well as with increasing soy milk concentrations. In the Mozzarella cheese analogue generated using the milk mixtures, the fat content decreased with increase in the soy milk concentration, while it decreased during the storage period. Lactose levels were lowest in cheese composed of soy milk or raw milk and processed by UF, and decreased during storage in cheese produced using milk mixtures. In milk mixtures containing soy milk, the protein concentration increased with increasing amounts of raw milk and did not change during the storage period. The water-soluble nitrogen compound level was similar between cheeses and increased only slightly during storage. The amount of non-protein nitrogen compounds was higher in the cheese analogue than in the control cheese and tended to increase during storage. Analysis of the physicochemical traits of the Mozzarella cheese analogue yielded the following results: During storage, titratable acidity levels increased while pH tended to decrease. After analysis using electropherograms, it was classified as ${\alpha}$-, ${\beta}$-, or ${\kappa}$-casein. The results of rheometry tests showed that in the Mozzarella cheese analogue prepared from milk mixtures, with raw milk concentrated by UF, increases in concentration rate lead to lowered hardness, elasticity, cohesiveness, and brittleness. When cheese was produced from milk mixtures and concentrated by UF, meltability increased as the concentration rate increased, although to an extent that was less than that observed for the control cheese, and tended to increase during storage. Sensory evaluation showed that the analogue cheese was much better than the control cheese in terms of formation, appearance, and flavor.

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Comparison of Antioxidant Activities and Carotenoid Contents Between Marketable and Unmarketable Sweet Pepper Fruits (파프리카 상품과 및 비상품과의 항산화 활성 및 카로티노이드 함량 비교)

  • Yoon, Seungri;Kim, Jin Hyun;Shin, Minju;Jeong, Ho Jeong
    • Journal of Bio-Environment Control
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    • v.31 no.4
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    • pp.393-400
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    • 2022
  • Postharvest quality of sweet pepper fruits was mainly defined as external appearance, i.e., shape, fruit weight and surface color. These quality traits tend to involve esthetic appeal, it disregards gustatory properties and nutritional value. However, comparative studies according to the marketability of sweet pepper fruits are insufficient. This study was carried out to compare the physicochemical components, antioxidant activity and carotenoid contents of marketable and unmarketable sweet pepper fruits (Capsicum annuum L.). Physicochemical components (proximate composition, minerals and total phenolic contents) and antioxidant activities using various methods were investigated. The proximate composition values (%) of marketable and unmarketable fruits were: moisture (90.28 and 90.29), ash (0.74 and 0.26), crude protein (0.67 and 0.72), crude lipid (0.38 and 0.32). There were no significant differences in antioxidant activity, while total phenolic content was higher in marketable fruit. Carotenoids contents were 29.3 ± 2.6 and 31.9 ± 2.9 ㎍·g-1 in marketable and unmarketable fruits respectively, and identified β-carotene, violaxanthin, neoxanthin, and zeaxanthin. Lutein and capsaicin were not detected. In this study, potential value of unmarketable sweet pepper fruit could be identified to be applied as a food ingredient and functional food material.

Effects of Edible Seaweed on Physicochemical and Sensory Characteristics of Reduced-salt Frankfurters

  • Choi, Yun-Sang;Kum, Jun-Seok;Jeon, Ki-Hong;Park, Jong-Dae;Choi, Hyun-Wook;Hwang, Ko-Eun;Jeong, Tae-Jun;Kim, Young-Boong;Kim, Cheon-Jei
    • Food Science of Animal Resources
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    • v.35 no.6
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    • pp.748-756
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    • 2015
  • The effects of sea tangle, sea mustard, hijiki, and glasswort were investigated based on the proximate composition, salinity, cooking loss, emulsion stability, pH, color, texture profile analysis, apparent viscosity, and sensory characteristics of reduced-salt (NaCl) meat batter and frankfurters. The moisture content, salinity, lightness of the meat batter and frankfurter, hardness, gumminess, and chewiness of the reduced-salt frankfurters with sea weeds were lower than the control without seaweed (p<0.05). The protein content, springiness, and cohesiveness of the reduced-salt frankfurters were not significantly different among the treatments (p>0.05). The moisture content, salinity, cooking loss, lightness, redness, hardness, gumminess, and chewiness of treatments with sea tangle and with sea mustard were lower than the control (p<0.05). Among the sensory traits, color was highest in the control (p<0.05). The flavor was also highest in the control. The treatments with sea tangle and with sea mustard samples had high tenderness, juiciness, and overall acceptability scores similar to the control (p<0.05). The results of this study show that the combination of low-salt and seaweed in the formulation successfully improved reduced-salt frankfurters, improving sensory characteristics to levels similar to the regular salt control (1.5%).

Comparison and Correlation Analysis of Different Swine Breeds Meat Quality

  • Li, Yunxiao;Cabling, Meriam M.;Kang, H.S.;Kim, T.S.;Yeom, S.C.;Sohn, Y.G.;Kim, S.H.;Nam, K.C.;Seo, K.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.7
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    • pp.905-910
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    • 2013
  • This study was performed to determine the influence of pig breed and gender on the ultimate pH and physicochemical properties of pork. The correlations between pH and pork quality traits directly related to carcass grade, and consumer's preference were also evaluated. The pH and meat grading scores for cold carcasses of 215 purebred pigs (Duroc, Landrace, and Yorkshire) from four different farms were obtained. Meat quality parameters of the pork loin were analyzed. Duroc and female animals were more affected compared to other breeds and male pigs. Duroc animals had the highest ultimate pH, carcass back fat thickness, marbling scores, yellowness, and fat content (p<0.05). Landrace pigs had the highest color lightness and cooking loss values (p<0.05). Among all trait parameters, marbling scores showed the highest significant differences when evaluating the impact of breed and gender on meat quality characteristics (p<0.001). Ultimate pH was positively correlated with carcass weight (0.20), back fat thickness (0.19), marbling score (0.17), and color score (0.16) while negatively correlated with cooking loss (-0.24) and shear force (-0.20). Therefore, pork samples with lower ultimate pH had lower cooking loss, higher lightness, and higher shear force values irrespective of breed.

Effects of Starter Cultures on the Quality Traits of Electron Beam Irradiated Fermented Meat during Aging (전자선 조사된 원료육과 Stater Culture의 사용이 발효육의 숙성 중 품질에 미치는 영향)

  • Lim, Dong-Gyun;Seol, Kuk-Hwan;Lee, Moo-Ha
    • the MEAT Journal
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    • s.35 winter
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    • pp.46-55
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    • 2008
  • The microbiological and physicochemical properties of irradiated (2 kGy) or non-irradiated fermented meats processed with or without a commercial starter culture were evaluated during fermentation and aging. The pH of irradiated (2 kGy) fermented meats with starter cultures dramatically decreased during fermentation and aging (p<0.05), and the final pH was 4.25. The total aerobic counts and lactic acid bacteria counts reflected the addition of the starter culture. As the fermentation progressed, the total aerobic counts closely paralleled the lactic acid bacteria counts. The TBARS values of irradiated fermented meats increased regardless of the treatment during fermentation and aging. These results show that the irradiated(electron-beam) meat/fat resulted in the reduction of the total microbes and survives lactic acid bacteria. The use of starter cultures in meat batters post-irradiation may be useful for the production of fermented meats.

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Quality Characteristics of Dry-cured Ham Made from Two Different Three-way Crossbred Pigs

  • Yim, Dong-Gyun;Hong, Doo-Il;Chung, Ku-Young
    • Asian-Australasian Journal of Animal Sciences
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    • v.29 no.2
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    • pp.257-262
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    • 2016
  • This study was conducted to compare the physicochemical traits of dry-cured hams made from two different three-way crossbred pigs: Yorkshire${\times}$Landrace${\times}$Duroc (YLD) and Yorkshire${\times}$Berkshire${\times}$Duroc (YBD). Animals were slaughtered at a live weight of 110 to 120 kg and cooled at $0^{\circ}C$ for 24 h in a chilling room, the ham portion of the carcasses were cut and processed by dry-curing for physico-chemical analyses. While the moisture and crude protein contents of dry-cured ham were higher in YLD than in YBD, crude fat and ash content were higher in YBD (p<0.05). The salt contents of ham from YBD were higher than those from YLD (p<0.05). YBD ham samples showed a higher $L^*$ and $b^*$ values than those from YLD, while YBD ham showed lower $a^*$ value (p<0.05). Thiobarbituric acid reactive substances (TBARS) and volatile basic nitrogen (VBN) values of YLD hams were lower than those of YBD samples (p<0.05). Hardness, gumminess, chewiness, and shear force values of YBD ham were higher than those of YLD sample (p<0.05). Saltiness was significantly higher in YBD ham than in YLD samples (p<0.05). YLD ham displayed a superior quality than YBD. Considering the meat quality parameters of two-way crossbred ham, YLD hams could be more suitable for the production of dry-cured products.

Effects of Starter Cultures on the Quality Traits of Electron Beam Irradiated Fermented Meat during Aging (전자선 조사된 원료육과 Stater Culture의 사용이 발효육의 숙성 중 품질에 미치는 영향)

  • Lim, Dong-Gyun;Seol, Kuk-Hwan;Lee, Moo-Ha
    • Food Science of Animal Resources
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    • v.27 no.3
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    • pp.308-313
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    • 2007
  • The microbiological and physicochemical properties of irradiated (2 kGy) or non-irradiated fermented meats processed with or without a commercial starter culture were evaluated during fermentation and aging. The pH of irradiated (2 kGy) fermented meats with starter cultures dramatically decreased during fermentation and aging (p<0.05), and the final pH was 4.25. The total aerobic counts and lactic acid bacteria counts reflected the addition of the starter culture. As the fermentation progressed, the total aerobic counts closely paralleled the lactic acid bacteria counts. The TBARS values of irradiated fermented meats increased regardless of the treatment during fermentation and aging. These results show that the irradiated (electron-beam) meat/fat resulted in the reduction of the total microbes and survives lactic acid bacteria. The use of starter cultures in meat batters post-irradiation may be useful for the production of fermented meats.

Effects of Different Drying Methods on Quality Traits of Hanwoo Beef Jerky from Low-Valued Cuts during Storage

  • Lim, Dong-Gyun;Lee, Sang-Suk;Seo, Kang-Seok;Nam, Ki-Chang
    • Food Science of Animal Resources
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    • v.32 no.5
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    • pp.531-539
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    • 2012
  • To determine the effects of various drying methods on the quality characteristics of beef jerky from low-valued cuts, Hanwoo beef shank muscles were either hot air-dried, shade-dried, or sun-dried. The physicochemical quality and microbiological safety of the Hanwoo beef jerky were analyzed during a storage of $25^{\circ}C$. Moisture content and water activity ($a_w$) of the samples decreased as the time period of storage increased, regardless of the drying condition (p<0.05). Shade-dried jerky showed higher $a_w$ compared to others after storage of 20 d (p<0.05). The pH value of hot air-dried jerky was higher than those of others (p<0.05). For color properties, sun-dried samples showed higher redness ($a^*$) and yellowness ($b^*$) compared with the properties of others (p<0.05). The hot air-dried jerky showed higher shear force values than the sun-dried or the shade-dried jerky after 10 and 20 d (p<0.05). However, the total plate counts (TPCs) of naturally dried jerky (shade and sundried) were higher than hot-air dried jerky after storage of 10 and 20 d (p<0.05). With regard to sensory properties, naturally dried jerky showed higher tenderness, juiciness, and overall acceptability scores than the hot air-dried jerky (p<0.05). In conclusion, although natural drying appears to be more susceptible to microbiological contamination than hot air-drying, the natural drying method seems to result in superior quality than the hot air drying method.