• KOREAN JOURNAL OF CROP SCIENCE
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• v.64 no.2
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• pp.127-136
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• 2019

Sweet sorghum (Sorghum bicolor L. Moench), compared to traditional crops, has been evaluated as a useful crop with high adaptability to the environment and various uses, but cultivation has not expanded owing to a lack of related research and information in Korea. This study was conducted to estimate heading date in 'Chorong' sweet sorghum based on climate data of the last 30 years (1989 - 2018) from six regions (Jeonju, Buan, Jeongup, Imsil, Namwon, and Jangsu) in Jellabuk Province. In addition, we compared the growth and quality factors by sowing date (April 10, April 25, May 10, May 25, June 10, June 25, and July 10) in 2018. Days from sowing to heading (DSH) increased to 107, 96, 83, 70, 59, 64, and 65 days in order of the sowing dates, respectively, and the average was 77.7 days. The effective accumulated temperature for heading date was $1,120.3^{\circ}C$. The mean annual temperature was the highest in Jeonju, followed in descending order by Jeongup, Buan, Namwon, Imsil, and Jangsu. The DSH based on effective accumulated temperature gradually decreased in all sowing date treatments in the six regions during the last 30 years. DSH of the six regions showed a negative relationship with mean temperature (sowing date to heading date) and predicted DSH ($R^2=0.9987**$) calculated by mean temperature was explained with a probability of 89% of observed DSH in 2017 and 2018. At harvest, fresh stem weight and soluble solids content were higher in the April and July sowings, but sugar content was higher in the May 10 ($3.4Mg{\cdot}ha^{-1}$) and May 25 ($3.1Mg{\cdot}ha^{-1}$) sowings. Overall, the April and July sowings were of low quality and yield, and there is a risk of frost damage; thus, we found May sowings to be the most effective. Additionally, sowing dates must be considered in terms of proper harvest stage, harvesting target (juice or grain), cultivation altitude, and microclimate.

• Korean Journal of Food Science and Technology
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• v.2 no.2
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• pp.17-25
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• 1970

Juice were extracted from fresh leaves of 70 species of plants growing in Korea by mincing and pressing the resulting pulp through a cotton cloth. Leaf protein concentrates could be prepared from many species of land and water plants that are at present economically unimportant. The choice of plants is of considerable important. Total-N, protein-N and pH determinations were made on the extracts, and total-N remaining in the fibre were calculated. Leaf protein concentrates were precipitated from the extracts at $75{\sim}80^{\circ}C$, and analysed total-N as protein-N of products. The present paper deals with the calculated yields of leaf protein concentrates from various plants, relations between yield of leaf protein concentrates and total-N of leaves, or pH of extracts, and the amino acid compositions of leaf protein concentrates. Results are summarized as follows. 1. Spinach and radish were the best sources of easily extractable, but good results were also obtained with indian mustard, kail, chenopod, red bean, cucumber, squash, houndberry, white flowered gourd, potato, Humulus japonicus, arrowroot and soybean as a good resources for the production of leaf protein concentrates. 2. In general, the greater the protein content of leaves the greater the yield of leaf protein concentrates. However, there are some plants difficult to make a adequate protein extraction by a simple mechanical process. 3. It was to be expected that leaf protein concentrates would be more extractable with the higher pH of extracts. There were a poor yield of the leaf protein concentrate in the pH values lower than 5.50 of the first extracts. 4. Protein content of the leaf protein concentrate shows marked differences, depending on species and season. It ranged between 29 to 80% of protein contents. However, the majority of plants yielded products containing more than 50% of protein. Products containing more than 75% of protein were obtained from two species of radish and indian mustard. Cabbage and Digitaria sanguinalis cilialis (summer) made products containing 29 to 32% of protein. 5. The amino acid composition of leaf protein concentrates was not greatly altered by species of plants. On an amino acid compositional basis, the leaf protein concentrate has a favorable balance of essential and non-essential amino acids, the only exception being methionine, which was usually low in all cases.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.12
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• pp.1906-1912
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• 2014

To evaluate the effect of freezing temperature on quality of blueberries, blueberry fruit was frozen at -20, -45, and $-70^{\circ}C$ immediately after harvest. After 24 hr of freezing, frozen blueberries were stored at $-20^{\circ}C$ for 2 months. Blueberries were thawed at $4^{\circ}C$ or $25^{\circ}C$ and subjected to subsequent analyses of drip ratio, fruit hardness, pH of juice, color, and sugar content. Frozen berries at all three temperatures did not show any significant difference in pH or sugar content compared with fresh berries. The drip ratio of berries decreased as the freezing temperature decreased. Thawing conditions significantly affected the drip ratio of berries frozen at $-20^{\circ}C$. Hardness of berries was significantly reduced after freeze-thawing. Freezing and thawing reduced total aerobic bacteria and yeast/mold numbers by more than 2 log regardless of freezing or thawing temperature ($4^{\circ}C$ or $25^{\circ}C$). Cross-section of blueberries did not show different shapes by freezing temperature. Further studies such as sensory evaluation are needed to determine the optimum freezing temperature regarding quality and cost.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.4
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• pp.1084-1091
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• 2015

Aquaculture of olive flounder started in the middle of 1980's and now farming has been taken place in many places along the coastal line in Korea. The taste of olive flounder has a good chewy texture because of high collagen content, low fat content, so it is popular for sliced raw fish. Olive flounder is popular among Koreans but the consumption pattern is uniformly so as to be used as sliced raw fish but not other ways. So, now there needs to develop high valued-processed food using olive flounder. This study was set to investigate the processing of terrine by using olive flounder, in which terrine is French style meat loaf that is well favored around the world. In this study, terrine was prepared by chopping olive flounder meat with 39 g egg white and 10 mL fresh cream (per 50 g fillet) and then seasoned with 5 mL lemon juice, 5 mL brandy, 0.05 g salt and 0.05 g pepper. The 25 g of dough was placed on a vinyl wrap, put with 2 g cheese, and layered an another 25 g dough, and then rolled up and wrapped by aluminium foil. Two different cooking methods were used for terrine processing in this study. Terrine-1 was cooked by vacuum sealed in polyethylene film ($20{\times}30{\times}0.05mm$) after boiling for 5 min and stored at $-20^{\circ}C$ for 7 days. Terrine-2 was prepared by vacuum sealed in polyethylene film ($20{\times}30{\times}0.05mm$) and stored at $-20^{\circ}C$ for 7 days. After 7 days, Terrine-1 was thawed and then heated up in microwave for 2 min (Sample-1), while Terrine-2 was thawed and then boiled in water for 5 min (Sample-2). Viable bacterial count, chemical composition, pH, salinity, hardness, TBA, free amino acid content, and sensory evaluation were measured for both Sample-1 and Sample-2. Especially, the scores of sensory evaluation of Sample-2 is slightly higher than that of Sample-1. On the other hand, there were no significant differences on color, odor, taste, texture, and overall acceptance between Sample-1 and Sample-2.