• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.11
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• pp.1327-1335
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• 2017

This study was carried out to determine the effect of cacao bean addition on the physicochemical properties of extruded rice flour. Rice-based cacao beans (0, 20, 40, 60%) were extruded at a die temperature of $130^{\circ}C$, screw speed of 200 rpm, and moisture content of 25%. As the content of cacao beans increased from 20% to 60%, expansion index decreased, while piece density and specific length increased. The water soluble index and water absorption index of the extrudate increased through extrusion cooking. Lightness decreased as cacao bean content increased while redness increased. As the content of cacao beans increased, paste viscosity decreased. Cold peak viscosity was observed in all extrudates of raw roasted cacao beans. ${\alpha},{\alpha}$-Diphenyl-${\beta}$-picrylhydrazyl (DPPH) radical-scavenging activity increased upon extrusion and cacao bean addition. As content of cacao beans increased, non-roasted cacao beans had higher total phenolic contents than roasted cacao beans. This study showed that addition of cacao beans to extruded rice snack improved antioxidant activity.

• Applied Chemistry for Engineering
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• v.25 no.1
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• pp.90-95
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• 2014

Nylon66 extrudates as a function of the extrusion number were prepared by a twin screw extruder. Chemical structures, thermal properties, melt index, crystal structures, mechanical properties such as the tensile strength, elongation at break and impact strength, and rheological property were measured by FT-IR, $^1H$-NMR, melt indexer, DSC, TGA, XRD, universal tensile tester, Izod impact tester, and rheometer. FT-IR and $^1H$-NMR characterizations indicated that the number of extrusions did not affect the chemical structure. The decrease in the molecular weight was checked by the melt index of extrudates. There were no effects of the thermal history on the melting and degradation temperature. The tensile and impact strength and modulus were found to be similar, regardless of the number of extrusions, but the elongation decreased significantly. The complex viscosity of extrudates at low frequencies decreased with the extrusion number. No structural changes after extrusion were confirmed from the fact that there was no change in the slope and shape of G'-G" plot.

• Food Science and Preservation
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• v.18 no.3
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• pp.271-278
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• 2011

Considering the importance of cassava as food crops in humid tropics, the effect of feed moisture (20, 25%) and barrel temperature (110, $130^{\circ}C$) on physical properties (piece density, expansion, mechanical properties, color, water solubility index, water absorption index) and pasting properties of extruded cassava starch was investigated. The feed moisture used during extrusion processing had a significant effect on extrudates SME input, specific length and piece density at (p<0.05) while effect on cross-sectional expansion index, apparent elastic modulus and breaking strength in bending shown significantly at p<0.1. Furthermore, the interaction effect of feed moisture and barrel temperature gave a significantly affected the SME input and piece density (p<0.1), specific length (p<0.05) and on redness (p<0.01). The increase in water injection rate led to increase in piece density, apparent elastic modulus, breaking strength in bending, cold peak viscosity, breakdown and final viscosity and decrease in cross-sectional expansion index and specific length. It was found that the extrusion cooking process did not affect the value of color L, color b, water solubility index and water absorption index. Thus, the results of this study can be useful to some extent in developing extruded cassava starch as human and animal feeds.

• Food Engineering Progress
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• v.15 no.2
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• pp.155-161
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• 2011

The aim of this study was to determine the effects of different extrusion conditions on the saccharification characteristics( initial reaction velocity, reaction rate constant, yield) of extruded corn starch. Extruded corn starch-water slurries were mixed with alpha-amylase for the enzymatic saccharification. The saccharification yield of extruded corn starch was high at lower feed moisture content and higher barrel temperature. The solubility of extrudates increased with increase in the SME input which increased with increase in the feed moisture content. Starch hydrolysates having DE 63.8 was obtained after 2 hr reaction. The initial reaction velocity of the extrudate slurry with alpha-amylase was higher with decrease in the feed moisture content. The initial reaction velocity of extruded corn starch was the highest ($2.26{\times}10^{-3}mmol/mL{\cdot}min$) at 25% feed moisture content and $120^{\circ}C$ barrel temperature, 250 rpm screw speed. The pregelatinized starch was $1.83{\times}10^{-3}mmol/mL{\cdot}min$ as a control. Reaction rate constant was a similar trend to initial reaction velocity.

• Journal of Fisheries and Marine Sciences Education
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• v.27 no.6
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• pp.1822-1831
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• 2015

This study was carried out to optimize coating process of the rice snack added with dried shrimp powder by using single extruder. A total of 8 independent variables were used for 4 independent variables of edible oil coating and 4 independent variables of seasoning coating. 4 independent variables for edible oil coating were set up as 10, 15, 20, 25 and 30% for the content of edible oil; 40, 50, 60, 70 and $80^{\circ}C$ for the tumbler temperature; 60, 70, 80, 90 and 100 rpm for the tumbler speed; 2, 3, 4, 5 and 6 min for the coating time. 4 independent variables for seasoning coating were set up as 2, 3, 4, 5 and 6% for the content of seasoning; 40, 50, 60, 70 and $80^{\circ}C$ for the tumbler temperature; 50, 60, 70, 80 and 90 rpm for the tumbler speed; 2, 3, 4, 5 and 6 min for the coating time. The characteristics of the dependent variables as coating yield and Breaking ratio of collet due to the condition changes of the independent variable was studied during process of edible oil coating and seasoning coating, respectively. As a results of this study, 20% of edible oil content, $70^{\circ}C$ of tumbler temperature, 80 rpm of tumbler speed, 4 min of coating time for process of edible oil coating, 3% of seasoning content, $60^{\circ}C$ of tumbler temperature, 70 rpm of tumbler speed, 3 min of coating time for process of seasoning coating were found to be the most preferable over other independent variables for the production of snack. In conclusion, it is necessary to set the independent variable in order to produce the high quality snack added with the rice as the main raw material and dried shrimp, edible oil and seasoning as the sub-materials.

• Journal of the Korean Society of Food Science and Nutrition
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• v.43 no.2
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• pp.258-264
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• 2014

This study investigated the effects of die temperature and repeated extrusion on the chemical components and antioxidant properties of extruded white ginseng (EWG). Die temperature was adjusted to 100, 120, and followed by repeated extrusion under the same conditions with corresponding samples. Secondary extruded white ginseng (SEWG) at a die temperature of $120^{\circ}C$ had the highest acidic polysaccharide content of all extrudates. Increasing die temperature and repeated extrusion both increased crude saponin content of the extrudate. Ginsenoside Rh1 was detected in the EWG ($140^{\circ}C$) and SEWGs, whereas ginsenosides Rg3s and Rg3r were only detected in SEWG ($140^{\circ}C$). The highest total phenolic content, DPPH radical scavenging activity, and reducing power obtained from SEWG ($140^{\circ}C$) were $8.55{\pm}0.03$ mg/g, $72.05{\pm}0.63%$, and $0.80{\pm}0.004$, respectively. In conclusion, repeated extrusion increases antioxidant activity and crude saponin contents for the development of improved ginseng products.

• Journal of Animal Science and Technology
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• v.44 no.6
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• pp.783-792
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• 2002

This experiment was conducted to investigate the effects of supplementary level of extruded poultry manure, corn and tapioca mixture (EPM) on growth performance, nutrient digestibility and body composition in korean native goats. Total 15 heads of Korean native goats (10 kg B.W.) were randomly assigned into five treatment groups (EPM 10, 20, 30, 40% and control.) and feeding trial was done for six weeks with ad libitum. Protein level of the extrudate with poultry manure was directly proportional to corn supplements rate. NFE and Ca content in EPM also were functional of the tapioca supplements levels. Daily body weight gain was significantly (p<0.05) reduced in EPM 40% group, but no significant differences were observed in other groups. Concentrate feed intake was high in EPM 10 to 30% groups, compared to the control. Feed conversion ratio also was relatively higher in EPM groups than in the control. As EPM level increased, dry matter digestibility was proportionally decreased, but that of crude protein was enhanced. Dressed carcass percentage was significantly (p<0.05) reduced with the increase of EPM level, showing control 49.7, EPM 10% 49.8, EPM 20% 48.3, EPM 30% 47.9 and EPM 40% 45.2, respectively.

• Korean Journal of Food Science and Technology
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• v.30 no.5
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• pp.1128-1133
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• 1998

Extrusion cooking treatment was compared with autoclaving/cooling treatment for formation of enzyme resistant starch of high amylose corn starch (HACS). Effects of barrel temperature $(100^{\circ}C,\;120^{\circ}C,\;140^{\circ}C)$ and feed moisture content (25%, 35%, 45%) on extrusion processing in a co-rotating twin-screw extruder under fixed screw speed (100 rpm) were investigated by measuring enzyme resistant starch (RS) yield. RS yield were estimated by in-vitro pancreatin digestion method and enzymatic-gravimetric method using termamyl. Barrel temperature and yield of RS were negatively correlated and feed moisture content and yield of RS was positively correlated as determined by in-vitro pancreatin method. The highest yield (38.4%) of RS was obtained from HACS extrudate processed at the barrel temperature of $100^{\circ}C$ and the feed moisture content of 45%, while the yield of RS by 5 times of autoclaving/cooling was 25%. The yield of RS by in vitro pancreatin digestion method was 20.7% with high amylose corn starch and 8.2% with ordinary corn starch (CS), respectively, under the same extrusion condition (barrel temperature $120^{\circ}C$, feed moisture content 35%). At the same condition, the yields of RS by enzyme-gravimetric method were 14.6% with HACS and 6.8% with CS, respectively. The yield of RS increased during the storage at $4^{\circ}C$ for 4 weeks and the highest yield (60%) was obtained by the storage of HACS extrudates extruded at $100^{\circ}C$ and 45% feed moisture content.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.27 no.1
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• pp.13-26
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• 1994

The present study was focused on investigation of proper processing conditions to develop physicochemical properties of extrudates using sea mustard and corn by single extruder. Response surface analysis was used to evaluate effects of extrusion variables on the quality of the extrudates. Physicochemical dependence variables of sea mustard extrudates with corn grits show a significance correlation of within $5\%$. Among the various dependence variables, the expansion ratio showed a high correlation with bulk density, break strength, water solubility index and yellowness. Bulk density correlated closely with water solubility index; break strength with water absorption index and lightness, and water absorption index with lightness. Water solubility index and lightness showed a significance correlation with yellowness of within $0.5\%$. Three dimensional graphic analysis on response surface regression was conducted with each of the dependent variables which revealed statistically significant relationship to independent variables: $15{\sim}21\%$ moisture content, $10{\sim}30\%$ sea mustard content and $95{\sim}115^{\circ}C$ die temperature. Expansion ratio decreased with increasing moisture and sea mustard content. It showed the highest value at $18\%$ moisture content, $10\%$ sea mustard content and $95^{\circ}C$ die temperature. and the lowest value was at $21\%$ moisture content, $30\%$ sea mustard content and $105^{\circ}C$ die temperature. Bulk density was highest at $21\%$ moisture content, $30\%$ sea mustard content and $105^{\circ}C$ die temperature. On the other hand, it was lowest at $18\%$ moisture content, $10\%$ sea mustard content and $95^{\circ}C$ die temperature. Break strength was highest at $18\%$ moisture content, $10\%$ sea mustard content and $115^{\circ}C$ die temperature, but lowest at $21\%$ moisture content, $30\%$ sea mustard content and $105^{\circ}C$ die temperature. Water solubility index increased in the range of $43.9{\sim}54.8\%$ as the moisture content increased.