• The Journal of the Korea Contents Association
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• v.18 no.3
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• pp.648-657
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• 2018

The purpose of this study was to analyze the labeling of commercial protein bars in Korea and USA to develop Korean protein bars. Furthermore, we compared protein contents of products with daily protein intake, DRI, and AMDR. The protein bars were sampled in off- and on-line markets of both countries, with 17 in Korea and 113 in the US. As the results, since US products have bigger than one serving size than Korean ones, the intake of overall nutrients is higher, especially protein and sodium. Protein contents (per 100 g) of products in US were higher than those of Korea. The highest protein was soy protein isolate (SPI) in Korea and whey protein isolate (WPI) in the US. This is thought to be influenced by the preference and familiarity of food according to the country. In conclusion, since there are difference in eating habits, intake and preference of the protein source, it is necessary to develop suitable protein bars for Koreans. Therefore, this research provides the baseline of protein bars for consumers to choose products.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.5
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• pp.379-386
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• 1990

Varietal difference of protein content in forty eight Korean recommended rice cultivars and environmental Variation in protein content of milled rice harvested at six sites of the middle and/or southern plain and four locations of mid-mountainous and/or alpine area in 1989 were investigated. Also, the composition of amino acid in milled rice was compared among three rice varieties: a high-protein japonica rice, Nongbaek, a high-protein Tongil-type rice, Yongjubyeo, and a low-protein japonica rice, Hwaseongbyeo. Korean recommended rice varieties showed 7.93% of average protein content with varietal variation from 5.5% to 10.2% for milled rice harvested in 1988, and 9.17% of mean protein content with the variation from 6.3% to 12.0% for milled rice harvested in 1989. Tongil-type rice was about 1% higher in protein content of milled rice than japonica. The low-protein japonica rice, Hwaseongbyeo exhibited lower content of essential amino acids per g of rice flour sample than the high-protein japoinica, Nongbaek and/or Tongil-type rice, Yongjubyeo, but the relative content of essential amino acids per 16.8g of nitrogen in milled rice of the former was not so different with those of the latters. Among amino acids the content of glutamic acid was highest and among essential amino acids the content of leucine was highest while methionine was lowest. The protein content of milled rice was negatively correlated with days from seeding to heading, K/Mg ratio, alkali digestion value(l-7) and amylose content, but it was positively correlated with translucency and magnesium content of milled rice. The protein content of milled rice harvested in the southern plain paddy field was about 1% higher compared with those harvested in the Middle plain. Also, the protein content of milled rice harvested in the southern mid-mountainous and alpine area was about 0.8% higher compared with those harvested in the resemble altitude area of the middle-northern part of Korea. The contribution of environmental variation to total in plain area was about 28.1% while that in mid-mountainous and alpine area was about 56.4%.

• The Korean Journal of Food And Nutrition
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• v.14 no.3
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• pp.199-203
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• 2001

땅콩유 제조시 땅콩의 침지시에 NaHCO$_3$를 첨가하는것과 분쇄전에 땅콩을 열처리하는 것이 n-hexanal 함량에 미치는 영향을 조사하기 위하여 headspace gas chromatgraphy 방법을 이용하여 조사하였다. 분쇄전에 땅콩을 열처리한 경우에는 n-hexanal함량이 현저하게 감소됨을 알 수 있었으며 열처리 시간이 증가함에 따라 n-hexanal 함량도 감소하지만 땅콩유중의 충고형분과 단백질함량도 함께 감소하였다. 이상의 결과로볼 때 콩비린내의 원인물질 중의 하나인 hexanal 함량의 감소를 위해서는 두유의 경우처럼 분쇄전에 땅콩을 열처리하는 것은 필수적이지만 지나친 열처리는 땅콩유는 단백질함량을 감소시켜 영양가가 저하시키므로 땅콩을 10분간 가열하는 것이 가장 바람직한 가공조건이라고 판단된다.

• Korean Journal of Poultry Science
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• v.12 no.1
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• pp.39-44
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• 1985

These studies were conducted to compare the nutritive values and optimum prices of eggs among 6 groups of different egg Weight. With the total of 100 eggs of each weight group, after the weight percentage of egg yolk, albumen and shell in the whole egg were investigated, protein and fat contents of e99 yolk and albumen were analyzed. and then protein and fat contents in the whole eggs were calculated. Finally, the optimum prices of eggs in relation to the egg weight were studied on the basis of egg weight, protein content and protein plus fat contents of eggs, respectively. The results obtained are summarized as follows; 1. As the egg weight (X, g/10 eggs) increased, egg yolk (Y$_1$, %) and shell(Y$_2$, %) percentages tended to decrease, but egg albumen(Y$_3$, %) percentage increased lineally; Y$_1$=44.34-0.02X, Y$_2$=15.358-0.006 X, and Y$_3$=40.136＋0.026 X. 2. There were no significant differences in protein and fat contents of eggs among 6 different groups of egg weight. 3. Protein (Y$_1$, %), fat (Y$_2$, %) and protein plus fat (Y$_3$, %) contents in the whole eggs declined progressively as the egg weight (X, g/10 eggs) increased ; Y$_1$=11.943-0.00032X, Y$_2$=13.996-0.00614X, and Y$_3$=25.939-0.00646X. 4. Similar results were obtained whether the optimum prices of eggs were estimated on the basis of egg weight or protein content of eggs, and they were higher in the large size eggs and lower in the small size eggs than the optimum prices of eggs estimated on the basis of protein plus fat content of eggs.

• Journal of Aquaculture
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• v.21 no.1
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• pp.19-25
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• 2008

We investigated the proper dietary protein and lipid levels for growth and body composition of juvenile sea cucumber Stichopus japonicus. Three replicate groups of the sea cucumber(average weight of 1.1 g) were fed the experimental diets containing different levels of protein(10, 20, 30 and 40%) and lipid(3, 7 and 11%) for 10 weeks. At the end of the feeding trial, survival of each group was over 87%, and there was no significant difference among the groups. Weight gain and specific growth rate(SGR) of sea cucumber were significantly affected by dietary protein(P<0.005) and lipid levels(P<0.001). The highest weight gain and SGR were observed when sea cucumber fed the diet containing 30% protein with 3% lipid(P<0.05). Weight gain and SGR of the sea cucumber fed the diet containing 3% lipid were higher than the other groups at the same protein level except for 40% protein group(P<0.05). Protein content of the sea cucumber fed the diet containing 30% protein with 3% lipid was significantly (P<0.05) higher than those fed 20% protein diets with 7% or 11% lipids and 10% protein diet with 7% lipid. Moisture, lipid and ash contents of the whole body were not significantly different among the groups. Fatty acid compositions such as linoleic acid, EPA(20:5n-3) and DHA(22:6n-3) of the whole body were affected by those of dietary lipid sources. The results of this study indicate that the diet containing 30% protein and 3% lipid is optimal for growth of juvenile sea cucumber.

• Korean Journal of Food Science and Technology
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• v.31 no.3
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• pp.586-592
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• 1999

The objective of this study was to investigate the fundamental characteristics of proteins effecting on Korean wheat flour quality. Mixing properties and protein contents of Eunpa, Allgreu, and Woori showed soft wheat characteristics. Tapdong had strong dough stability and high protein content like hard wheat flour. However, even though Greu had a high protein content, the dough strength was very weak like soft wheat flour. No major difference was observed in protein solubility with water, 0.1N NaCl, 70% ethyl alcohol, 0.1 N acetic acid solution and in sulfur and disulfide contents between Korean wheat flours and imported flours. However, DNS (Dark Norther Spring) had more contents of acid insoluble and SDS insoluble proteins compared with Korean wheat varieties. PAGE pattern of Tapdong was very similar to imported wheat flours at the high molecular weight regions and characteristic high molecular weight glutenin subunits were observed over 116 kD protein molecular weight region from 4 Korean wheat flours such as Eunpa, Woori, Allgreu, and Greu.

• Korean Journal of Food Science and Technology
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• v.51 no.6
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• pp.537-542
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• 2019

Proteins were isolated from four species of edible insects, Bombyx mori, B; Tenebrio molitor, T; Protaetia brevitarsis, P; and Gryllus bimaculatus, G, and their properties were analyzed and compared with those of whey proteins. The yield of the protein isolated from raw materials was 65.0-75.0%. Among three branched chain amino acids (BCAA), the amounts of valine in all the insects were similar to that of the whey protein. The BCAA content was 16.8 and 16.4% in G and T, respectively. The total polyphenolic content and the antioxidant activity of the insect proteins were significantly higher than those of the whey proteins. Based on the sensory test of the protein powder, the whey protein could be replaced by 25% of the isolated protein from the insects, but the taste and flavor needs to be improved. Although the BCAA content of insect proteins was lower than that of the whey protein (by 73-76%), their application could be useful because of high polyphenolic content and the anti-oxidative activity.

• Applied Biological Chemistry
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• v.36 no.6
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• pp.533-538
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• 1993

The Wx protein, known as starch synthase or starch glucosyl transferase (E.C. 2.4.1.11), is responsible for the amylose synthesis. In an effort to explain the mechanism of amylose biosynthesis, the starch synthase known as Wx protein was identified by analyzing the various wx rice mutants with SDS-PAGE of proteins extracted from rice starch. Finally, the 66 kDa protein was purified by extracting the starch-bound protein fractions followed by Suprose 12 gel filtration chromatography.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.1
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• pp.78-82
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• 2012

Soybean [$Glycine$ $max$ (L.) Merr.] protein is a high quality source for food and feed. But, antinutritional factors in the raw mature soybean are exist. Kunitz trypsin inhibitor (KTI) protein is a main antinutritional factor in soybean seed. Also, P34 protein, referred as $Gly$ $m$ Bd 30K, has been identified as a predominant immunodominant allergen. Genetic relationship between KTI protein and P34 protein could be useful in soybean breeding program for the genetic elimination or reduction of these factors. The objective of this study was to determine the independent inheritance or linkage between KTI protein and P34 protein in soybean seed. A total of 479 $F_2$ seeds were obtained from the cross of 07B1 and PI567476 parents. KTI protein and relative amount of P34 protein were analysed from $F_2$ seeds harvested from the F1 plants by using SDS-PAGE and Western blot analysis. The segregation ratios of 3 : 1 for KTI protein (353 KTI protein present : 126 KTI protein absent) and relative amount of P34 protein (363 normal amount of P34 protein : 116 low amount of P34 protein). The segregation ratio of 3 : 1 suggested that KTI protein and relative amount of P34 protein in mature soybean seed were controlled by a single major gene. The segregation ratios of 9 : 3 : 3 : 1 (266 KTI protein present, normal amount of P34 protein: 88 KTI protein present, low amount of P34 protein: 102 KTI protein absent, normal amount of P34 protein: 23 KTI protein absent, low amount of P34 protein) and Chi-square value (${\chi}^2$=3.31, P=0.346) were observed in $F_2$ seeds. This data showed that KTI protein was inherited independently with relative amount of P34 protein in soybean. These results will be helpful in breeding program for selecting the line with lacking KTI protein and reduced amount of P34 protein in soybean.

• Korean Journal of Food Science and Technology
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• v.7 no.2
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• pp.82-84
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• 1975

In polished barley of 22 varieties protein content was correlated significantly with MgO of $P_2O_5$ content (at p=0. 01), $K_2O$ (at p=0. 05), but it was not related to CaO. Dye binding capacity was correlated significantly (at p=0. 01) with MgO or $P_2O_5$. Thus MgO could be used for mass screening of protein content. Carbohydrate content showed insignificant negative correlation coefficients with above four minerals. There were significant positive correlation (at p=0. 01) among $P_2O_5$, $K_2O$ and MgO. The mean contents of $K_2O$, $P_2O_5$, MgO and CaO were 0. 03, 0. 29, 0. 084 and 0. 043%, respectively.