• Applied Biological Chemistry
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• v.29 no.1
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• pp.16-21
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• 1986

Free sugars of Kochujang which were prepared with different starch sources, i.e., glutinous rice, polished barley, wheat flour and sweet potato, were investigated for three months of aging. Glucose was found in all tested samples during aging period and the content increased with time, particularly higher for glutinous rice while lower for sweet potato. Fructose also was found through aging period, its content increased for a month and decreased later. The data showed higher fructose content in the order of sources of sweet potato, wheat flour, polished barley and glutious rice. Maltose and sucrose were detected only at the beginning of aging period and the content were less than 3.5% for maltose in all of samples and than 0.4% for sucrose with glutinous rice and wheat flour. Trace amount of rhamnose was detected in the Kochujang made from polished barley.

• Journal of the Korean Society of Food Culture
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• v.32 no.4
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• pp.323-331
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• 2017

This study examined the quality characteristics of Jeung-pyeon made with wet non-glutinous rice flour and rice wine. The samples of Jeung-pyeon were prepared with different ratios of cooked purple sweet potato (0, 3, 6, 9, and 12%) to analyze the water content, sugar content, pH, chromaticity, texture characteristics, and sensory evaluation. No significant difference in water content, sugar content, and springiness was observed among the 5 samples. The pH and volume showed the highest level at 0%. The L-value and b-value decreased while the a-value increased. The hardness, chewiness, and gumminess were highest at 9% and lowest at 12%. The extent of violet chromaticity and pore size were optimal in 9%. In addition, 9%-added purple sweet potato showed the highest score of odor, taste, texture, and overall acceptability. In conclusion, the optimal addition for the highest acceptability of cooked purple sweet potato was 9%.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.16-24
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• 1973

Breads were made from composite flours based on domestic resources and their quality was assessed to obtain the following results. 1) When barley bread was made according to the formula for standard wheat bread, its specific loaf volume (SLV) was quite low (1.3 at 100% addition of water) in comparison with 3.3 for wheat bread. Addition of 10% defatted soy flour increased its SLV to 1.7 (at 100% water). Among various flour-improving additives, the use of 1.5% GMS + 0.5% CSL gave best results (SLV: 2.0 at 100% water). Admixture of wheat flour with the composite flour based on barley was most effective. Replacement of barley flour with 25% wheat flour gave SLV of 2.8 (at 90% water) and that with 50% wheat flour gave SLV of 3.2 (at 90% water), comparable to standard wheat bread with respect to loaf volume, color and texture. 2) Sweet potato bread had the characteristics of turning black-brown on baking. Use of 20% defatted soy flour and GMS + CSL gave higher SLV (1.9 at 100% water). Addition of wheat flour at 25% or 50% level to the composite flour based on sweet potato flour gave SLV of 2.3 and 2.6, respectively, at 90% water and its color and texture were improved 3) Potato flour was different from sweet potato flour in baking, the effect of GMS + CSL being quite low. Bread from corn flour was different from barley flour bread and defatted rice bran was not suitable for bread-making. 4) Bread was made from following composite flours based on naked barley and sweet potato flours along with the use of proper additives: (a) naked barley flour + defatted soy flour + wheat flour (45 : 10 : 45) (b) naked barley flour + defatted soy flour + wheat flour (67 : 10 : 23) (c) naked barley flour + defatted soy flour (90 : 10) (d) sweet potato flour + defatted soy flour + wheat flour (40 : 20 : 40) (e) sweet potato flour + defatted soy flour (60 : 20 : 20) Sensory evaluation of above breads in comparison with standard wheat bread (So) gave the following decreasing order of scores, So>(a)>(b)>(c)>(e)>(d) and Duncan's multiple range test showed that bread (a) was not different from standard wheat bread significantly at 5% level, in overall evaluation including color, texture, taste and flavor.

• Korean Journal of Food Science and Technology
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• v.5 no.1
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• pp.6-15
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• 1973

In an attempt to develop composite flours based on raw materials available in Korea, six domestic resources were investigated with respect to their physical and chemical properties, nutritive value and economy. The results are summarized as follows: 1) Flours from naked barley, sweet potato, potato, corn, defatted rice bran and defatted soybean were compared in respect of their proximate composition, thiamine content and protein score. 2) In color comparison, naked barley and defatted soy flours were comparable to wheat flour whereas corn and sweet potato flours were a little inferior. In raising power, naked barley and defatted soy flours were similar to wheat flour and others were inferior. 3) In maximum viscosity of flours by amylograph, naked barley, corn and potato flours were higher than wheat flour and others were lower. In viscosity in cooling, corn flour was similar to wheat flour and naked barley and potato flours were lower. Addition of $10{\sim}20%$ defatted soy flour into other flours generally caused the lowering of viscosity. Addition of emulsifiers such as glyceryl monostearate, calcium stearyl lactylate, Methocel and Emulthin into the flours manifested different effects on the amylogram. 4) In nutritional test by rat, diets consisting of naked barley, sweet potato, potato or corn flours, each containing defatted soy flour (at 10% level with exception of 20% for sweet potato flour) and naked barley flour fortified with lysine were similar to wheat flour in digestibility, but were superior in NPU and biological value. 5) In price estimation, sweet potato and corn flours were competitive with wheat flour, but naked barley flour was a little expensive. On the other hand, barley and sweet potato are promising in terms of domestic production.

• Korean Journal of Food Science and Technology
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• v.44 no.1
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• pp.28-33
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• 2012

The effect of puffing conditions on the physical properties and sensory evaluations of a puffed snack (ppeongtuigi) made of purple sweet potato flour was investigated. The snacks consisted of coated artificial rice with purple sweet potato flour with water, tempered to 7%, 9% and 11% moisture. The coated material was puffed at 236, 241, or $246^{\circ}C$ for 4, 5, or 6 s. The $L^*$ value decreased as the heating time increased. The $a^*$ and $b^*$ values, specific volume, and hardness increased with increasing heating temperature and heating time. Puffed snacks produced under conditions of higher moisture (7%), higher heating temperature ($246^{\circ}C$), or longer heating time (5 s) showed high scores for appearance, color, taste, and overall acceptability in sensory evaluations.

• Journal of Nutrition and Health
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• v.17 no.4
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• pp.262-272
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• 1984

A study on the balance of essential amino acids in Korean diet and further investigation on quality of protein through optimum combination of foods using the least square method based on FAO/WHO (1973) provisional score patterns were carried out The results of the optimum gross combination are summarized as follows: 1) The first limiting amino acids of the Korean diet was found to be methionine and cysteine based on both whole egg and FAO/WHO (1973) provisional score patterns. 2) Weight ratios between rice and beef, chicken, pork, rabbit meat are 7 : 3, 4 : 1, 4 : 1, and 3 : 1. The amino acid score and the least amino acid are 100(phe+tyr), 99(thr), 111(trp), and 109(leu) for each combination. This result indicates that pork and rabbit meat can be high quality protein sources for the rice eating people. 3) Weight ratios between rice and anchovy, saury, ark shell, pollack, cuttle fish, tuna and herring are 2 : 1, 5 : 1, 3 : 2, 3 : 1, 3 : 1, 4 : 1, and 3 : 1. 4) Weight ratios between potato and rice, wheat flour are 8 : 1 and 24 : 1. Lysine, the limiting amino acid of rice and wheat flour can be complemented by combining these with potato. 5) It is possible to apply this idea on typical Korean dishes. For example, in case of soybean-sprout rice the optimum combinations of rice : soybean-sprout : pork and rice : soybean-sprout : beef are 4 : 1 : 1 and 11 : 1 : 5. It is of utmost importance to pursue further more desirable combinations with more complex food items and transform the result obtained by the computer analysis into more practical terms for practical use.

• Applied Biological Chemistry
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• v.37 no.3
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• pp.154-160
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• 1994

Pregelitinized rice (PR), pregelitinized waxy rice (PWR), and pregelitinized rice flour (PRF) were evaluated for physico-chemical properties comparing with rice starch and acetylated potato starch. L value was decreased during drum drying. PFR had the highest value (P<0.05) for water absorption index and PWR had the highest value for water solubility index. Transmittance of gelitinized samples had drastically increased at $80{\sim}90^{\circ}C$. PWR had the highest value for apparent viscosity and rice samples had a steady apparent viscosity during heating at $90^{\circ}C$. Viscosity was decreased as pH decreased at room temperature and drastically decreased below pH 2. Rice starch and PR had no significant effect for change of pH. Change of viscosity had more effect for hot temp. than room temp.. Pregelitinized samples showed only second peak for DSC. PWR had the lowest value for degree of retrogradation and acetylated potato starch had the highest value for freeze-thaw-stability.

• Applied Biological Chemistry
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• v.23 no.3
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• pp.157-165
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• 1980

Kojis were prepared from the different starch raw materials such as glutinous rice, barley rice, wheat flour and sweet potato, and were tested in an effort to reduce production cost and to improve quality of Kochuzang(red pepper paste). During the starting period of Koji preparation, there were less significant changes in pH; however, pH decreased somehow in the case of sweet potato, whereas it increased for the other Kojis. In general, the highest acidity was obtained after 72 hours of Koji preparation. Total nitrogen, soluble nitrogen and amino-nitrogen content increased in order of wheat flour, barley rice, and glutinous rice; Kojis they were markedly produced between 72 and 96 hours of Koji preparation. The maximum amount of reducing sugar was observed between 48 and 72 hours of Koji preparation during this period the reducing sugar content varied widely depending on starch source. Sweet potato Koji produced the highest level of ethyl alcohol content after 72 hours of Koji preparation; for the other Koji the same trends were observed after 24 hours. The starch liquefying activities have reached the highest level after 96 hours and for glutinous rice and barley rice; however, they kept on increasing until 120 hours for wheat flour and sweet potato. Koji Starch liquefying and saccharogenic amylase activities tended to increase in order of sweet potato, glutinous rice, barley rice and wheat flour. Kojis Various protease activities were measu-red during the Koji preparation, and they increased in order of alkali, neutral and acidic protease.

• Journal of Nutrition and Health
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• v.7 no.1
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• pp.17-23
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• 1974

Digestibilities of flour of white wheat, barley, potato, sweet potato, are $5{\sim}11$ percent (3hrs.) in unripe starch state and in gelatinization, digestibilities are up to $20{\sim}30$ percent (3hrs.). And in two states, digestibilities of flour of potato and sweet potato are lower than barley and white wheat flour. If it is not gelatinization, digestibilities of biscuit and cracker are much lower than popped cake (29%). In gelatinization, digestibilities of biscuit and cracker $(19{\sim}29%,\;3hrs.)$ are similar to gelatinized flour of materials. Digestibilities of bread and castern is $21{\sim}32$ percent, it is similar to gelatinized flour of materials. And bread is higher than castera. Digestibility of on the marketing weaning food (II) (15%, 3hrs.) is much lower than food (I) (24.1%, 3hrs.) When the date of manufacturing passed $1{\sim}2$ months, digestibility of some cookies have a tendency to low. When mothers choice the infant weaning food, they consider metritional value (42%) and digestibility (27%). Also when they make weaning food at home, they generally use flour of rice (41%) and white wheat (23%). And they think, the rate of digestion is 49% in the rice flour and white wheat (23%). It was sort of cooked of rice (16%) and weaning food on the marketing(13%), which accepts to good digest. Also it was sort of biscuits (44%) which comparatively high choice snack food.

• Applied Biological Chemistry
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• v.24 no.2
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• pp.120-125
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• 1981

Organic acids of Kochuzang (red pepper paste) prepared from glutinous rice, polished barley, wheat flour and sweet potato were analyzed by a gas chromatography. Lactic, pyruvic, succinic, fumaric, malic, pyroglutamic and citric acid were identified. And trace amount of oxalic acid was found in the Kochuzang prepared from sweet potato. The dominant organic acid of all samples was pyroglutamic acid, followed by pyruvic and citric acid. The organic acids were lower in Kochuzang from wheat flour than in other samples. The contents of succinic and fumaric acid were highest in Kochuzang prepared from sweet potato and were lowest in polished barley Kochuzang.