• Microbiology and Biotechnology Letters
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• v.19 no.5
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• pp.514-520
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• 1991

Direct synthesis of cyclodextrin (CD) from extruded insoluble corn starch without liquefaction procedure using cyclodextrin glucanotransferase (CGTase) was carried out. Increased CD production rate and yield were achieved in heterogeneous enzyme reaction system containing extruded corn starch compared with those of conventional system employing liquefied or partially cyclized starch. At extruded starch concentration of 100 g/l the CD concentration and conversion yield were reached up to 54 g/l and 0.54, respectively. High purity of $\alpha \beta \gamma$-CDs without accumulation of undesirable malto-oligosaccharides was produced, furthermore, the residual extruded starch was easily separated by centrifugation from reaction mixture, whlch will facilitate the purification procedure. Granular structure of extruded starch was observed by SEM to investigate enzyme reaction mechanism. Supplemental addition of $\alpha$-amylase enhanced slightly the initial CD production rate, but it decomposed produced CD at the late stage. Various! extruded raw starches, such as, corn, rice, and barley were also suitable substrates for CD production.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.3
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• pp.436-442
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• 1997

Corn starch was extruded under relatively low shear, high moisture, and low temperature. Puffing of corn starch dough was induced by injecting $CO_2$gas in the range from 0MPa to 0.09MPa. Piece density and compressive modulus for puffed corn starch were decreased by increasing the injection pressure to 0.07MPa, and increased above 0.07MPa. the microstructure of corn starch puffed with $CO_2$gas showed thick cell size, compared with those puffed with steam. RVA paste viscosity curves of corn starch puffed with $CO_2$had different patterns from those puffed with steam, probably resulted from partial gelatinization of starch. Water absorption and solubility were not significantly changed by $CO_2$injection pressure, but the average degree of polymerization was reduced by higher $CO_2$injection. The water absorption, water solubility, and the average degree of polymerization for corn starch puffed with $CO_2$were significantly lower than those puffed with steam.

• 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.

• Microbiology and Biotechnology Letters
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• v.22 no.1
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• pp.106-113
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• 1994

A novel method for production of concentrated purity maltose using swollen extruded corn starch was investigated. Degree of gelatinization of extruded starch suitable for maltose formation was found to be around 70%. The optimal amiunt of enzyme was 400 unit fungal $\alpha $-amylase per g of starch, and the reaction time was 12 hours. At extruded starch concentration of 300 g/l(w/v), maltose concentration and content were reached up to 220 g/l(w/v) and 77%(w/w), respectively. The maltose forming reaction was also successfully proceeded at high starch concentration of 700 g/l(w/v), however, the conversion yield and content were decreased. By the addition of extruded starch by fed-batch wise, the maltose concentration, purity, and conversion yield could be improved up to 465 g/l(w/v), 70%(w/w), and 0.63, respectively. The investigated maltose production process seems to have many potential advantages over the conventional process utilizing liquefied starch, and the feasibility for industrial application needs to be evaluated.

• Journal of the Korean Society of Food Science and Nutrition
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• v.42 no.8
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• pp.1290-1295
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• 2013

The aim of this study was to evaluate the quality characteristics of bread supplemented with extruded corn fiber. The extrusion was conducted as the moisture content of the corn fiber reached 30% and 40% (at $140^{\circ}C$ and 200 rpm). The bread baked with 5% extruded corn fiber at a 40% feed moisture exhibited the highest specific volume. The hardness of the bread supplemented with 10% corn fiber was the highest during storage compared to bread supplemented with extruded corn fiber and the control (100% wheat flour). However, the hardness of bread with corn fiber or extruded corn fiber (5%) was lower than the control. In the sensory evaluation, preferences decreased with the increased addition of untreated and extruded corn fiber. Quality characteristics, such as specific volume and texture, of bread baked with extruded corn fiber were better than bread baked with corn fiber. This improvement in quality is likely due to modification of corn fibers and starch gelatinization from the extrusion process. Supplement of extruded corn fiber had the potential for bread making compared to raw corn fiber.

• Preventive Nutrition and Food Science
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• v.6 no.3
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• pp.158-162
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• 2001

Blends of pork meat (20%), defatted soy flour (25%), and corn starch (48.61~53.71%) were prepared with or without additional non-meat ingredients, i.e., onion powder (1%), alone or in combination with carrot powder (1.5%) or extract (1.5%), or defatted oat flour (5%). All blends were formulated for 22.78% moisture, with water added where necessary. They were extruded using a laboratory single-screw extruder at 16$0^{\circ}C$ profess temperature and 170 rpm screw speed. The additional ingredients generally decreased product expansion and increased bulk density and shear force. When the product with no additional ingredient and the product with onion powder were evaluated by trained sensory panelists, \"grain complex\" was the most intense flavor note for both. With 1 % onion powder in feed, a distinct \"onion\" flavor note was detectable in extrudates. All the products may be considered \"healthful\" based on nutrient profiles.t; based on nutrient profiles.

• Proceedings of the Korean Society for Food Science of Animal Resources Conference
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• 1997.06a
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• pp.19-39
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• 1997

Extrusion conditions were optimized for blends of ground lamb and starch using a single-screw extruder for the purpose of producing expanded snack-type products. A central composite rotatable response surface methodology(RSM) design was used with variation in feed moisture, process temperature, and screw speed. The three variables significantly affected one or more of the measured physical properties of extrudates. The optimum conditions for minimum shear force values were 26.5% feed moisture, $148^{\circ}C$ process temperature, and 134 rpm screw speed. Lean ground beef, chicken, goat, lamb or mutton was blended with corn starch, and extruded at the optimum condition established from RSM experiments. Physical/rheological properties were generally similar, water activity was low (<0.12) and total aerobic plate counts were <10 for all products. Extrudates containing chicken had the highest ratio of polyunsaturated fatty acids to saturated fatty acids, whereas those containing beef had the highest ratio of monounsaturated fatty acids to saturated fatty acids. Sensory data indicated that texture was acceptable and flavor characteristics were not different among the products.

• Food Science and Preservation
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• v.31 no.4
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• pp.518-526
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• 2024

This study analyzed the quality of texturized vegetable protein (TVP) made from defatted soy flour combined with flour or starch from rice sources. The base raw material formulation consisted of 50% soybean protein, 30% gluten, and 20% rice flour and rice starch. A cooling die-equipped extruder was used with a barrel temperature of 190℃ and screw rotation speed of 250 rpm. The hardness and cutting strength of the extruded TVP were found to be higher for white rice than for glutinous rice and higher for flour than for starch. Gumminess and chewiness were similar across rice types, but higher for flour than for starch. White rice TVP had a lower water absorption capacity than glutinous rice TVP. Turbidity was lowest for white rice flour and highest for corn starch. Using rice flour instead of starch in TVP production can simplify processing and contribute to promoting the consumption of rice.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.2
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• pp.192-199
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• 2000

Eight crossbred barrows (four growing and four finishing pigs with average initial BW of 40 and 82 kg, respectively) were fitted with T-cannulas at the distal ileum and used in a 36 d metabolism experiment ($4{\times}4$ Latin squares) to determine the effects of roasting and extruding full-fat soybeans on nutrient utilization. Treatments were: 1) soybean meal; 2) roasted soybeans; 3) extruded soybeans; and 4) soybeans extruded with an extrusion enhancer (sodium sulfite). The control diet was corn starch-based with 0.90% lysine, 0.65% Ca and 0.55% P for the growing pigs and 0.75% lysine, 0.55% Ca and 0.45% P for the finishing pigs. For the growing pigs, apparent total tract digestibilities of DM (p<0.04) and GE (p<0.008) were greater for soybean meal than full-fat soy products. However, ileal digestibilities of DM, GE, N and most amino acids were, in general, greatest for extruded soybeans and lowest for roasted soybeans, with soybean meal intermediate. For finishing pigs, trends in digestibilities of nutrients were very similar to those for the growing pigs. Total tract digestibilities of DM (p<0.03) and GE (p<0.001) for soybean meal were greater than for the full-fat soy products and ileal digestibilities of DM, GE, N and most amino acids were greater for the extruded soybeans than for the roasted soybeans. In conclusion, nutrient digestibilities and availabilities of indispensable amino acids tended to be greatest in extruded soybeans, intermediate in soybean meal and lowest in roasted soybeans for growing and finishing pigs.

• 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.