• Korean journal of food and cookery science
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• v.32 no.4
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• pp.400-412
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• 2016

Purpose: This study was conducted to develop easy-made ssamjang products with differentiated materials and methods to meet the needs for a healthy and easy- lifestyle trend with lowered manufacturing expenses. Methods: Ssamjang was made with cheonggukjang and different kinds of jocheong as glutinous (GRSS), sweet potato (SPTSS), sweet pumpkin (SPKSS), bellflower root (BRSS) and ginger (GSS) and stored at $4^{\circ}C$ for 16 weeks. Quality characteristics and consumer acceptability were measured. Results: Titratable acidity was higher in SPTSS and rapidly increased (p<0.05) after 9 weeks in all groups during storage. Amino-type nitrogen contents of SPTSS and SPKSS were the highest and rapidly increased (p<0.05) after 5 weeks. Total free sugar content was higher in GRSS and did not change during storage. Glutamic acid and total free amino acid contents were higher in SPTSS, SPKSS and continuously increased up to 9 weeks. Yeast counts rapidly increased (p<0.05) after 9 weeks reaching 4.0 Log CFU/g in all groups except for SPTSS. Consumer acceptability did not change during storage in all groups and GSS was least preferable. Conclusion: The optimal quality maintenance period of ssamjang with cheonggukjang and jocheong was determined to 7-9 weeks of storage at $4^{\circ}C$ and ginger jocheong was the least preferable materials. We conclude that it is possible to develop easy-made ssamjang products with cheonggukjang and non-fermented materials also skipping aging period.

• Food Science of Animal Resources
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• v.34 no.5
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• pp.561-569
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• 2014

The purpose of this study was to determine the effects of using different amounts of potato puree (PP) (10 or 20%) and 10% bread crumbs (BC) as an extender and also control samples (C) with no added extender on chemical composition, energy values, cooking analyses, colour measurements, water holding capacity (WHC), penetration values, thiobarbituric acid value (TBA) and sensory analyses of meatballs. Meatball samples were cooked in a pre-heated $180^{\circ}C$ electric oven. Uncooked meatballs formulated with 20% PP had the highest moisture content. No significant differences were recorded for protein contents of uncooked samples. The highest cooking yield was found in samples extended with 10% BC. Increasing PP from 10% to 20% increased cooking yield of meatballs. 20% PP increased moisture and fat retention values and water holding capacity of meatballs. Meatballs with 10% BC had the lowest (the hardness in the texture) and meatballs with the 20% PP had the highest (the softness in the texture) penetration values. Formulating meatballs at a level of 20% resulted lower $L^*$ values. TBA values of control samples were higher than in PP added samples at the end of the storage period. Flavour scores for meatballs formulated with PP were higher than control and meatballs formulated with BC. Meatballs formulated with 10% PP had similar overall acceptability with meatballs added with 10% BC.

• Horticultural Science & Technology
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• v.19 no.4
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• pp.515-520
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• 2001

To observe the stimulating effect of low dose ${\gamma}$ radiation on the dormancy breaking and growth, microtubers of two potato cultivars (Solanum tuberosum L. cv. Dejima and cv. Superior) were irradiated at the dose of 0.5-30 Gy. Though it varied with cultivars and storage duration, sprouting rate, plant growth and tuber yield were promoted by 2-8 Gy irradiation in microtuber of 'Dejima' stored at low temperature. On the other hand, in microtuber of 'Superior', sprouting rate was promoted by 2 and 4 Gy irradiation, and the growth and tuber yield by 4 Gy irradiation. These results suggest that low dose of ${\gamma}$ radiation could have stimulating effects on the dormancy breaking of microtuber and potato growth.

• Korean journal of food and cookery science
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• v.13 no.4
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• pp.492-499
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• 1997

The effect of oxidants, gluten and gums on breadmaking quality of wheat-purple sweet potato(Ipomoea batatas) composite flour were studied. Alveograph tests of doughs showed that all additives increased the P, L and W values. Of these additives, L-Ascorbic acid, gluten, carboxy methyl cellulose have a significant effect on alveogram indexes. SEM showed that the dough added with additives changed some what in appearance when compared with the control. When oxidants was added, the doughs discontinuous gluten film were observed. No significant differences ,were evident in bread crumb color among the additives. And textural characteristics of bread crumb were influened by adding additives. Breads containing additives showed an increase in max weight, strength and hardness and a decrease in springness and cohesiveness. Average enthalpy values for all bread crumb after 7days increased with storage time. However, addition of additives decrease the rate of staling slightly more than that of the control. Addition of L-Ascorbic acid, L-Cystine, carboxy methyl cellulose and hydroxy propyl methyl cellulose increased the loaf volume significantly, and with except potassium bromate bread scores were acceptable.

• Korean Journal of Agricultural Science
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• v.25 no.1
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• pp.118-123
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• 1998

Lasiodiplodia theobrorme is a pathogen of Java black rot on sweet potato. This fungus infects the tuberous root during storage after harvest. Invasion of the fungus results in the expansion of necrosis sites into the tuberous roots. The resultant necrotic symptom of the tissue is also induced by application of acetone extract of the fungus growing on potato sucrose agar (PSA) culture. The active principles to induce the necrosis are purified from the acetone extract as follows. After evaporation of hexane-benzene-EtOAc (1:2:1, v/v/v) the extract was fractioned on silica gel column, using a solvent gradient system from n-hexane to EtOAc and then to MeOH. The active fractions were purified with HPLC on Nucleosil 50-5 column by eluting n-hexane to EtOAc. Their structures are established by using spectroscopic techniques and synthesis to 4-hydroxymellein and mellein, respectively. Application of small amount of these compounds induce expansion of the necrotic symptom into the tissue and accumulated ipomeamarone. Conclusively, these compounds acted as phytotoxins (inducing necrosis) and as elicitors (eliciting the phytoalexin).

• Korean journal of food and cookery science
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• v.23 no.6
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• pp.824-831
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• 2007

This study was conducted to investigate the quality characteristics of low-fat pork patties containing fat replacers. Pectin(PE) and potato starch(PO) were added as fat replacers and physicochemical properties of the patties were evaluated after oven-roasting or pan-frying. Uncooked and cooked pork patties formulated with the fat replacers were higher in moisture and ash content and lower in fat content than those of the control. The cooking yield and reduction in diameter of the patties were significantly improved by the addition of PE or PO and oven-roasting exhibited a higher cooking yield and lower reduction in diameter than pan-frying (p<0.05). Water holding capacity(WHC) and fat retention were highest in the patties formulated with PE, while the control had the lowest WHC when cooked by oven-roasting. The Hunter L (lightness) values were not different among the patties but the Hunter a (redness) and b (yellowness) values of the low fat pork patties were higher than those of the control and oven-roasting produced higher redness values than pan frying. Hardness and brittleness were lowest in the patties with PE, while cohesiveness and springiness showed no difference among the patties (p<0.05). The sensory analysis results showed that the use of PE or PO improved the overall acceptability of the low-fat pork patties. After 30 days of storage at $-20^{\circ}C$, pH and cooking yield decreased slightly, while hardness increased in all the patties.

• Korean Journal of Food Science and Technology
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• v.24 no.6
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• pp.547-551
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• 1992

The antioxidative effects of Rhus javanica $Linn{\acute{e}}$ ethanol extract (RE) with or without some synergists were determined by measurement of POV and TBA of oil in ramyun and potato flake fried in palm oil or lard. RE with ascorbic acid and with tocopherol significantly increased the oxidative stability of ramyun. The results obtained from sensory evaluation were similar to those of POV and TBA values. RE with phosphoric acid and with ascorbic acid retarded the oxidation of potato flakes fried in palm oil or lard during storage.

• Food Science and Biotechnology
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• v.17 no.4
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• pp.705-712
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• 2008

Sweet potato starch was modified using Thermus aquaticus $\alpha$-1,4-glucanotransferase ($Ta{\alpha}GT$), and its structural and rheological properties were investigated. $Ta{\alpha}GT$-modified starch had a lower amylose level and molecular weight than raw starch. The chain length distribution showed an increased number of short and long branched chains and the formation of cycloamyloses. Compared with raw starch, $Ta{\alpha}GT$-modified starch displayed a lower gelatinization enthalpy and a wider melting temperature range. The X-ray diffraction of $Ta{\alpha}GT$-modified starch was a weak V-type pattern with distinct sharp peaks at 13 and $20^{\circ}$. Scanning electron micrographs of modified starch exhibited big holes on the surface and the loss of granular structure. The frequency sweep measurement revealed that the gel of $Ta{\alpha}GT$-modified starch was more rigid than raw starch gel. However, the structure of modified starch gel was destroyed by heating at $75^{\circ}C$, and a firm gel was re-formed by subsequent storage at $5^{\circ}C$, indicating thermoreversible property.

• Korean journal of food and cookery science
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• v.23 no.2 s.98
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• pp.245-251
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• 2007

The purpose of this study was to examine how potato glycoalkaloid(PGA) contents changed as storing temperatures and periods changed for potatoes(Superior) cultivated in Korea. Some potatoes were stored at $5^{\circ}$C for 80 days, and others were stored at $20^{\circ}$C for 40 days. PGA contents were measured every 20 days for the potatoes stored at $5^{\circ}$C and 10 days for those stored at $20^{\circ}$C. The results can be summarized as follows. The amounts of a-chaconine and a-solanine measured on the first day of storage were 54.22 mg/100 g and 26.57 mg/100 g, respectively. Thus, the a-chaconine content was almost twice as much as the a-solanine content. The sprouts of potatoes stored at $5^{\circ}$C grew by 0.4 cm in 20 days, 1 cm in 40 days, 1.8 cm in 60 days, and 5.2 cm in 80 days. Furthermore, the PGA content increased by 3.5% in 20 days, 11.6% in 40 days, 23.4% in 60 days, and 41.4% in 80 days, compared to the PGA content on the first day. The sprouts of potatoes stored at 20 grew by 0.5 cm in 10 days, 2.3 cm in 20 days, and 7.4 cm in 40 days. Furthermore, PGA content increased by 12.5% in 10 days, 36.6% in 20 days, 44.8% in 30 days and 48.4% in 40 days, compared to the PGA content on the first day. Thus, we determined that potatoes stored at $20^{\circ}$C showed faster sprout growths and faster increases in PGA content than those stored at $5^{\circ}$C.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.184-189
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• 2008

Effects of sucrose at different concentrations (0, 10, 20, and 30%, w/w) on steady and dynamic shear rheological properties of sweet potato starch (SPS) paste (5%, w/w) were investigated. The steady shear rheological properties of SPS-sucrose composites were determined from rheological parameters based on power law and Casson flow models. At 25$^{\circ}C$ all the samples showed pseudoplastic and thixoropic behavior with high yield stress. Consistence index (K), apparent viscosity (${\eta}_{a,100}$), and yield stress (${\sigma}_{oc}$) values of SPS-sucrose composites decreased with increasing sucrose concentration from 10% to 30%. The decrease of swelling power was observed at higher sucrose concentration (>20%) and the low swelling power yielded a lower K, ${\eta}_{a,100}$, and ${\sigma}_{oc}$ values. In temperature range of 25-70$^{\circ}C$, Arrhenius equation adequately assessed variation with temperature. Oscillatory test data showed weak gel-like behavior. Magnitudes of storage (G') and loss (G") moduli increased with an increase in sucrose concentration and frequency. The SPS-sucrose composite at 30% concentration closely followed the Cox-Merz superposition rule.