• Elastomers and Composites
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• v.53 no.1
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• pp.6-12
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• 2018

Styrene-butadiene Rubber (SBR) Latex composites, incorporated with cellulose/starch-silica hybrids synthesized by gel-adsorption method, were filled into rubber by the latex compounding method. The structure morphology, mechanical properties, and thermodynamic properties of gel-silica hybrids were characterized. The states of hybrids which used as fillers were also characterized by SEM. As the fillers ratio increased, the difference for storage modulus of samples had been morphology by rubber process analyzer (RPA). Then, as more fillers ratio was filled into the matrix, the best tensile strength result, and the largest modulus value were also proved by UTM and RPA. As for thermal stability, increase in the ratio of fillers led to higher initial decomposition temperature, which was also proved by TGA. The swelling ratio of samples has also been characterized. From the results of all the tests, cellulose-silica hybrid showed the best results as a filler, and the best filling ratio of this hybrid is about 10 phr, which has the best storage modulus and great tensile strength.

• Food Science and Biotechnology
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• v.14 no.1
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• pp.68-72
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• 2005

Moisture sorption characteristics of edible composite films were determined and compared against moisture barrier properties. Edible composite films were Z1 (zein film with polyethylene glycol(PEG) and glycerol), Z2 (zein film with oleic acid), ZA1 (zein-coated high amylose corn starch film with PEG and glycerol), and ZA2 (zein-coated high amylose corn starch film with oleic acid). Z2 film showed the lowest equilibrium moisture content (EMC), monolayer value ($W_m$), water vapor permeability (WVP), and water solubility (WS). Surface structure of Z2 was relatively denser and finer than that of other edible films. GAB $W_m$ and C values decreased, while K values increased with increasing temperature. Correlation coefficients of WS:EMC and WVP:EMC at Aw 0.75 were higher than those of WS: $W_m$ and WVP: $W_m$, respectively. EMC values at Aw 0.75 appeared useful for evaluating or predicting moisture barrier properties of edible films.

• Korean Journal of Food Science and Technology
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• v.18 no.3
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• pp.215-220
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• 1986

Mechanical properties of 9-30% starch gels from naked and covered barley were investigated with rheometer or rotation viscosimeter. The compression-penetration curves of 20 and 30% gels were characterized by deformations containing elastic, plastic and fracture regions under the load of 0-2kg. The compressive stress relaxation test showed that the viscoelastic properties of 20% gels may be represented by four element Maxwell model consisting of two Maxwell element in parallel. Also, stress-decay under the steady shear of 9% covered starch gel was able to be interpreted by linear viscoelastic model and stress-decay process was suggested to be effective to investigate the effect of temperature or additives on gel structure.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.283-290
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• 1982

Sardine and mackerel so called dark muscled fish have been underutilized due to the disadvantages in bloody meat color, high content of fat, and postmortem instability of protein. Recent efforts were made to overcome these defects and develope new types of product such as texturized protein concentrates and dark muscle eliminated minced fish. Approach of this study is based on the rapid dehydration of foamed fish-starch paste by dielectric heating. In process comminuted sardine meat was washed more than three times by soaking and decanting in chilled water and finally centrifuged. The meat was ground in a stone mortar added Ivith adequate amounts of salt, foaming agent, and other ingredients for aid to elasticity and foam stability. The ground meat paste was extruded in finger shape and heated in a microwave oven to give foamed, expanded, and porous solid structure by dehydration. Dielectric onstant $(\varepsilon')$ and dielect.ic loss $(\varepsilon")$ values of sardine meat paste were influenced by wavelength and moisture level. Those values at 100 KHz and 15 MHz were ranged 2.25-9.86; 2.22-4,18 for E' and 0.24-19.24; 0.16-1.20 for E", respectively, at the moisture levels of $4.2-13.8\%$. For a formula for fish-starch paste preparation, addition of $20-30\%$ starch (potato starch) to the weight of fish meat, $2-4\%$ salt, and $5-10\%$ soybean protein was adequate to yield 4-5 folds of expansion in volume when heated. Addition of e99 yolk was of benefit to micronize foam size and better crispness. In order to provide better foaming and dehydration, addition of $0.2-0.5\%$sodium bicarbonate, foaming agent, was proper to result in foam size of 0.5-0.7 mm and foam density of $200-400\;/cm^2$ which gave a good crispness. Heating time was depended upon the moisture level of fish-starch paste. For a finger shaped paste (1.0cm. $D\times10cm.L$) heating for 150-200 sec. in a microwave oven (700W. 2.45GHz) was sufficient to generate foams, expand, and solidify the porous structure of fish-starch paste. When the moisture content was above $55\%$ browning and scorching was deepened due to over-expansion and over-heating whereas the crispness was hardened by insufficient expansion at lower moisture content. In quality evaluation of the product, chemical composition of $30\%$ starch and $3\%$ salt added product was moisture $8.8\%$, lipid $2.4\%$, carbohydrate $46.7\%$, protein $36.1\%$, and ash $6.0\%$. Eleven membered panel test evaluated that fish-starch paste was acceptable in color, crisp-ness, taste, except a trace of fishy odour which could be masked by the addition of spice extracts.

• Proceedings of the Botanical Society of Korea Conference
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• 2002.04a
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• pp.89-89
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• 2002

• Korean Journal of Food Science and Technology
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• v.28 no.3
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• pp.528-537
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• 1996

Qualify changes of microwave-reheated cooked rice aseptic-packaged with different lid materials and oxygen absorbers were determined during storage at $20^{\circ}C,\;30^{\circ}C$ and $40^{\circ}C$. Springiness cohesiveness and adhesiveness increased as storage temperature increased, while gumminess and hardness decreased. Lid materials oxygen absorbers, and storage temperatures showed no significant effect on the textural properties of cooked rice after microwave reheating. Degree of gelatinization was increased as storage temperature increased and was restored after microwave reheating. Scanning electron micrograph showed that the surface of cooked rice became rough and hollowed after microwave reheating for 1.5 min, indicating starch was regelatinized, while there was no difference with respect to lid materials. Photomicrographs of the cross-section of aseptic-Packaged cooked rice showed that a compact and solid structure increased and retrogradation occured in starch as storage temperature decreased, while a compact and solid structure was decreased and starch was regelatinized after microwave reheating.

• Journal of Microbiology and Biotechnology
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• v.34 no.8
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• pp.1727-1737
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• 2024

The quality of tobacco is directly affected by macromolecular content, fermentation is an effective method to improve biochemical properties. In this study, we utilized CBHA (cellobiohydrolase A) glycosylase, which was expressed by Pichia pastoris, as an additive for fermentation. The contents of main chemical components of tobacco leaves after fermentation were determined, and the changes of microbial community structure and abundance in tobacco leaves during fermentation were analyzed. The relationship between chemical composition and changes in microbial composition was investigated, and the function of bacteria and fungi in fermentation was predicted to identify possible metabolic pathways. After 48 h of CBHA fermentation, the contents of starch, cellulose and total nitrogen in tobacco leaf decreased by 17.60%, 28.91% and 16.05%, respectively. The microbial community structure changed significantly, with Aspergillus abundance decreasing significantly, while Filobasidum, Cladosporium, Bullera, Komagataella, etc., increased in CBHA treated group. Soluble sugar was most affected by microbial community in tobacco leaves, which was negatively correlated with starch, cellulose and total nitrogen. During the fermentation process, the relative abundance of metabolism-related functional genes increased, and the expressions of cellulase and endopeptidase also increased. The results showed that the changes of bacterial community and dominant microbial community on tobacco leaves affected the content of chemical components in tobacco leaves, and adding CBHA for fermentation had a positive effect on improving the quality of tobacco leaves.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.21-26
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• 2018

Thermoplastic starch (TPS) was prepared by mixing starch with glycerol as a plasticizer. The glycerol content ranged from 20 to 35 wt. % and TPS was prepared in a twin screw extruder. The shear viscosity, thermal and mechanical properties of the TPS were investigated. The viscosity of TPS exhibited typical shear thinning behavior: decreasing viscosity with increasing shear rate. The power index, n, increased with increasing glycerol content. This is because as the content of glycerol, a Newtonian fluid, increases, the viscosity behavior of the TPS becomes closer to that of a Newtonian fluid. The thermal behavior of TPS showed that starch and glycerol are miscible. In addition, when TPS was aged for more than one day at room temperature, TPS showed a partially miscible phase structure. The moisture absorbed into the TPS was assumed to change the phase behavior. The mechanical properties of TPS were found to be strongly dependent on the content of the plasticizer. Both the toughness and stiffness increased with increasing plasticizer content. DSC showed that this unusual result was due to the combined effect of humidity and the high amylose content in starch.

• Food Engineering Progress
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• v.21 no.3
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• pp.280-285
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• 2017

The objective of this study was to increase the efficiency of starch extraction from potato sludge by different concentration of food-grade hemicellulase. The potato sludge, which is a by-product of potato processing industry, was treated with food-grade hemicellulase. Starch extraction efficiency displayed no significant difference in hemicellulase concentration. The purities of potato starch increased from 83.40 to 95.91, 97.44, 95.58, and 97.79%, with treated 0.5, 0.75, 1.0, and 1.5% hemicellulase, respectively. The physicochemical properties of the starches, such as granule structure, particle size, pasting, and thermal transition, were not affected by the concentration of hemicellulase. These results indicate that food-grade hemicellulase treatment is an efficient method for starch extraction from potato sludge.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.51 no.6
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• pp.523-526
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• 2006

When $GA_{4}$ was applied to heading stage, it was examined to understand the change of plant hormones and starch during grain filling and ripening. Exogenous gibberellin caused a dramatic decrease in endogenous ABA content. Endogenous $GA_{4}$ content in both superior and inferior part was more promoted in $GA_{4}-treated$ rice grain than in the control. $GA_{1}$ content of an inferior part was not detected in the control and $GA_{4}-treated$ rice otherwise $GA_{4}$ was detected in all grain parts. Ripened grain rate in $GA_{4}-treated$ rice grain was lower than that of the control plant. Amylopectin from $GA_{4}-treated$ grain contained more very short chains with degree of polymerization (DP) between 4 and 8 than amylopectin from the control plant. It suggests strongly that fine structure of rice endosperm may be changed by exogenously applied $GA_{4}$ in rice plants.