• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.123-130
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• 1977

A laboratory study was made to develop a simple and economic model method for the systematic determination of functional properties of 'Soy Protein Isolates (SPI)' prepared from defatted soybean meal. These are required to evaluate and to predict how SPI may behave in specific systems and such proteins can be used to simulate or replace conventional proteins. Data concerning the effects of pH, salt concentration, temperature, and protein concentration on the functional properties which include solubility, heat denaturation, gel forming capacity, emulsifying capacity, and foaming capacity are presented. The results are as follows: 1) The yield of SPI from defatted soybean meal increased to 83.9 % as the soybean meal was extracted with 0.02 N NaOH. 2) The suitable viscocity of a dope solution for spinning fiber was found to be 60 Poises by using syringe needle (0.3 mm) with 15 % SPI in 0.6 % NaOH. 3) Heat caused thickening and gelation in concentration of 8 % with a temperature threshold of $70^{\circ}C$. At $8{\sim}12\;%$ protein concentration, gel was formed within $10{\sim}30\;min$ at $70{\sim}100\;^{\circ}C$. It was, however, disrupted rapidly at $125\;^{\circ}C$ of overheat treatment. The gel was firm, resilient and self-supporting at protein concentration of 14 % and less susceptible to disruption of overheating. 4) The emulsifying capacity (EC) of SPI was correlated positively to the solubility of protein at ${\mu}=0$. At pH of the isoelectric point of SPI (pH 4.6), EC increased as concentration of sodium chloride increased. Using model system$(mixing\;speed:\;12,000\;r.p.m.,\;oil\;addition\;rate:\;0.9\;ml/sec,\;and\;temperature\;:\;20{\pm}1\;^{\circ}C)$, the maximum EC of SPI was found to be 47.2 ml of oil/100 mg protein, at the condition of pH 8.7 and ${\mu}=0.6$. The milk casein had greater EC than SPI at lower ionic strength while the EC of SPI was the same as milk casein at higher ionic strength. 5) The shaking test was used in determining the foam-ability of proteins. Progressively increasing SPI concentration up to 5 % indicated that the maximum protein concentration for foaming capacity was 2 %. Sucrose reduced foam expansion slightly but enhanced foam stability. The results of comparing milk casein and egg albumin were that foaming properties of SPI were the same as egg albumin, and better than milk casein, particularly in foam stability.

• Korean Journal of Heritage: History & Science
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• v.52 no.4
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• pp.170-183
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• 2019

Fiber scutching refers to the process of extracting fibers from plants by separating or extracting fibers from the raw materials. As the definition of the term implies, the "Fiber Scutching" is performed on plants with advanced bast fiber as the primary material processing technique performed on plant materials. Some of the most popular phosphorus plants are ramie, hemp, flax, and the paper mulberry, which have a long history of cultivation and a wide range of distribution, making them very universal as a material supporting human life and culture. This study was described in Oju-yeonmunjangjeon-sango but was designed to re-examine the method of breaking dried stalks, which is currently unused in Korea, to examine the feasibility and characteristics of the technology. As a result of sampling and experimenting with hemp bast using the method recorded in the literature, hemp fiber was actually produced. The criteria for removing the shell from the hemp stem were the degree of discoloration and drying, and only when the stalk was completely discolored to yellow could segregation of the stalk from the shell be performed. The amount of sunlight and temperature were conditions that accelerated drying. However, if exposed for a long time, it is confirmed that hemp bast will be in a suitable condition to process, regardless of the amount of sunlight and temperature. 'Breaking of dried stalks', which utilizes the physical power of 'threshing with a flail' is considered a core process of the fiber scutching technique in 'Yukjin' in Hamgyeong-do. The bark and the core of the hemp were separated by tapping, the bast was thinly split, and the shell was peeled off, making it suitable for collecting with thread. The method of collecting the fibers by applying physical power causes downing on the fibers, which is to be generally avoided in the manufacture of bast fabric woven hemp or ramie. However, Hamgyeong-do's fiber scutching method seems to have applied this principle to the method of making fragile fabrics by using it in reverse. This method is distinct from the steaming or boiling of the stalks' in Andong, Korea, and it is similar to the Western method of spinning fabrics.

• Journal of Sericultural and Entomological Science
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• v.3
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• pp.1-11
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• 1963

This treatise is to set up a fundamental condition of checking silk lousiness and to set up a new improving method of cocoon bave lousiness after super refining treatment. It is also studied whether silk lousiness can be eliminated through the observation of the silk gland, or the lousiness can be able to improve through such a study. The conclusions obtained in this paper are as follows. 1. Silk lousiness is able to be observed most properly when the light direction and the fiber direction are parallel in plan view of the silk cloth and the greater the angle between them is, the less the lousiness is observed. When, however, the angle is greater than some specific angle(30$^{\circ}$), no more lousiness is observed. This specific angle is named by the author as Lousiness Horizontal Critical Angle. 2. Silk lousiness can be observed when the angle of light incidence against the silk cloth is six degrees, while the larger the angle is, the less the lousiness is observed. When, however, the angle is greater than same specific angle(45$^{\circ}$) the lousiness disappears. Such a specific angle is named by the author as Lousiness Vertical Critical Angle. 3. The best textile composition to decrease lousiness defect is plan weave, while twill and satin weave show more lousiness with the same silk fiber. 4. Lousiness was classified as Lousiness A, B, ana C of which A was the general lousiness, B was the group type, and C was the glucose type and the standard photographs for the lousiness grading of these types were prepared. 5. The proper soap-refining hours of silk for lousiness test was eight hours. 6. The greater the difference of fiber diameter between the cocoon single bave and the splitend was, the more lousiness was composed. The normal splitends were measured as 1/4-1/5 of the main fiber. 7. The lousiness was found at the cocoon shape ends more than other parts, and found at the middle cocoon layer than other layer which was imagined to be as a result of poor uniform bave spinning of silk worm. 8. Female cocoon had more lousiness than the male cocoon. 9. It was found that there was a great possibility to have the splitends through the observation of the anatomical silkgland, and the author reached a conclusion that the lousiness can be improved to a certain degree only by the elimination of abnormal silk gland from the breeding aspects. 10. The cocoon bave of the offspring after super refining lousiness test and selection showed more improved lousiness defect than that of the parents.