• Korean Journal of Human Ecology
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• v.5 no.1
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• pp.62-70
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• 2002

The objective of this study was to evaluate the effects of processing parameters of co-rotating twin screw extruder and dry methods on the level of resistant starch (RS) and the properties of extrudate prepared from normal maize starch. The processing parameters were used 90, 110, 130$^{\circ}C$ in temperature, 25.0~30.0% in moisture content, 150, 200, 250 rpm in screw speed and hot and cool air drying and drying after refrigerating in drying methods. The barrel temperature and drying methods had affected the level of resistant starch of extrudate. RS levels of extrudates were ranged from 2.4 to 15.5% by AOAC method. The extrudates, extruded at 110$^{\circ}C$ and then stored at 4$^{\circ}C$, showed the highest level of RS level (15.5%). Water absorption index increased with increasing moisture content and peak temperatures and viscosities of extudates decreased compare to that of raw starch from 94$^{\circ}C$ to 50~65$^{\circ}C$ and from 220 to 46~98 RVU, respectively. Extudates treated in 90$^{\circ}C$ and 110$^{\circ}C$ showed strong peak at $2{\theta}=6.7{\sim}17.0^{\circ}$ by X-ray diffractometry and had ~150$^{\circ}C$ endotherm like as that of RS3 starch by differential scanning calorimetry. In case of 130$^{\circ}C$, extrudates showed strong peak at $2{\theta}=20.0^{\circ}$ and had 106$^{\circ}C$ endotherm.

• Food Engineering Progress
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• v.15 no.1
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• pp.70-74
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• 2011

The effects of high pressure homogenization (microfluidization) on physicochemical properties of normal maize and oxidized maize starch film were studied. The molecular dispersibility of amlyose and amylopectin and the disintegration of granular structure had a marked effect on the physicochemical properties of starch films. The high pressure homogenized starch films showed increased solubility and transmittance due to the absence of gelatinized starch granules. The tensile strength of starch film increased significantly with decreasing oxygen permeability after high pressure homogenization, indicating that starch molecules were more uniformly and fully dispersed during the film formation. As a result, a clear starch film with improved mechanical properties was obtained after high pressure homogenization due to the increased interactions between the uniformly dispersed starch molecules.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.38 no.2 s.115
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• pp.22-34
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• 2006

To improve the mechanical properties of Hanji, starches such as maize, konyaku, and wheat powders were added at various concentrations in the manufacturing processes of Hanji. The effect of starches on the physical properties of Hanji was as follows. Filling rates of surface of hanji were increased with the increase of the concentration of starch. Hanji surface were completely filled at the 3.0% konyaku treatment. Konyaku powder showed higher filling rates than maize and wheat powder. The breaking length was increased with the increase of filling rates. Konyaku powder showed the highest breaking length: Tear index of hanji treated with maize and wheat powder were a little improved but that of hanji treated with konyaku powder were a little decreased compared to non-treated hanji. In conclusion, starch treatment showed the increase of the breaking length, but no effect on tear index.

• Food Science and Preservation
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• v.21 no.2
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• pp.286-293
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• 2014

In this study, one GRAS strain was screened from doenjang, a traditional Korean fermented food, as a microorganism producing amylase due to the formation of a clear zone on the medium including soluble starch. From the analysis of the gene sequence of 16S ribosomal RNA, the strain was identified as Bacillus subtilis and was therefore named Bacillus subtilis CBD2. When the nutrient broth medium was prepared with 3% NaCl, 5% glucose, and the initial medium pH 7.0, the B. subtilis CBD2 showed maximum growth. Among soluble starch, corn starch, maize amylopectin, and wheat starch, soluble starch was the most effective carbon source in the production of amylase by B. subtilis CBD2. The amylase from B. subtilis CBD2 showed the highest activities at pH 8.0 and $50^{\circ}C$, and corn starch was the most proper substrate for the enzyme activity. When corn starch was used as a substrate, the production of sugars through enzyme activity increased for 24 h, and then the enzyme activity became constant.

• Applied Biological Chemistry
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• v.27 no.2
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• pp.107-111
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• 1984

Changes of starch, soluble sugar and activities of amylase in germinating maize seeds were studied with comparison of germinating barley seeds. The starch in the endosperm was degraded slowly during the course of germination, and starch degradation of maize seeds compared with barley seed was found after 2 or 4 days of seed germination. There was a transient decline of soluble sugar come-its in ungerminated seed at early stages, followed by the rapid increase which concided with the degradation of starch. Activities of amylases were increased with the progress of germination, and maximum activities were founded after 8 days of seed germination. The higher activities of ${\alpha}$- and ${\beta}$-amylase were found at Hwang-ok maize and barley, respectively.

• Preventive Nutrition and Food Science
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• v.2 no.1
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• pp.11-16
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• 1997

Alkaline cooking and processing properties of domestic maize were evaluated by comparing to those of imported control maize(Asgrow 404). Domestric maize varieties were hydrated more rapidly and had lower dry matter losses during alkaline cooking than control maize due to softer endosperm texture and incomplete removal of pericarps. Domestic maize varieties produced masas with proper handling properties when nixtamals had 50~52% moisture. However, masas produced from domestic maizes were puffed dur-ing baking and frying process due to the release of more free starch granules in the masa than control masa. Tortilla chips prepared from domestic maizes absorbed more oil during frying and had slightly higher water content with darker color than tortilla chips prepared from control maize. Among the domestic maize hybrids, KS42/Fla2BT113 had more acceptable kernel characteristics of tortilla chips than other varieties.

• Korean Journal of Food Science and Technology
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• v.29 no.3
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• pp.516-521
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• 1997

Effect of amylose content on the physical properties of resistant starches (RS) from autoclaved maize starches (with starch:water=1:3.5, at $121^{\circ}C$) which were repeated up to 4 times heating-cooling cycles, were investigated by water uptake, scanning electron microscope (SEM) and differential scanning calorimetry (DSC). Amylose content of waxy maize starch (Amioca), common maize starch (PFP), high amylose starch(Amaizo, Amylomaize VII) were 0%, 29%, 50%, and 72%, respectively. Yield of RS increased as amylose content increased. Water uptake of all kinds of native starch was higher than that of RS, but lower than that of autoclaved starch. By SEM, RS showed some small particles on surface but the size of particles was different with amylose content. Single endothermic transition peak exhibited at $40{\sim}70^{\circ}C$ in autoclaved Amioca and PFP (crystalline melting of amylopectin) and at $132{\sim}169^{\circ}C$ in autoclaved Amaizo and Amylomaize VII(crystalline melting of amylose) by DSC. RS from all kinds of autoclaved starches except Amioca showed single endothermic peak over $155^{\circ}C$ but the enthalpy was not related to amylose content.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.5
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• pp.728-734
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• 1999

Thirty new born crossbred (Bos taurus${\times}$Bos indicus) calves, divided randomly in a $3{\times}2$ factorial design, were fed calf starters containing one of three protein sources i.e., groundnut cake (GN), cottonseed meal (CS) and meat and bone meal (MB) along with either raw (M) or gelatinized maize (MG) for 90d. Milk was fed upto 56d of age. Green oats and respective calf starters were offered from 14d of age onwards ad lib. Clinical profile of serum suggested significantly (p<0.05) higher albumin and lower alanine aminotransferase activity due to CS feeding. Alklaine phosphatase activity varied significantly (p<0.05) among dietary treatments showing interaction between protein and starch sources. Inclusion of gelatinized maize resulted in significantly higher concentration of serum globulin (p<0.05) and alkaline phosphatase activity (p<0.01). reduced (p<0.05) ruminal pH was accompanied by a significant decrease (p<0.01) in $NH_3-N$ concentration in the strained rumen liquor (SRL) of MG fed calves. Ruminal amylase activity was lower (p<0.05) on MG diets. Alanine aminotransferase activity in the rumen exhibited a significant (p<0.01) interaction between protein and starch sources. While feeding of CS significantly (p<0.01) reduced alanine aminotransferase activity, inclusion of thermally processed maize reduced (p<0.01) both aspartate and alanine aminotransferase activities in the rumen. The overall blood picture was similar among treatments, whereas rumen metabolites especially enzyme activities, seems to be altered with source of degradable protein an starch.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.35 no.3
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• pp.59-65
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• 2003

This research was conducted to investigate the physical properties of Hanji made using maize, konyaku, and wheat powders at various concentrations. Regardless of the starch types, the most effective concentration to increase the physical properties of Hanji was 2 percent. They were significantly improved even at the treatment conditions of 0.1 percent. All the Hanji treated showed the increase of the breaking length, bust index, and tear index and the decrease of the folding number. The strength properties of the Hanji treated were markedly improved at 8 to 10 percent weight increase. The highest mechanical properties were found in the Hanji treated with konyaku powder.

• Journal of the Korean Society of Food Science and Nutrition
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• v.34 no.3
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• pp.351-355
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• 2005

This study was performed to investigate the influences of resistant starch (HM: HI-MAIZE) and HM-D (HI-MAIZE DIET) fortified with D-factor (consisted of Psyliium husk, polydextrose and hydrocitric acid) on the glucose and bile acid absorption and production of short chain fatty acids (SCFA). HM-D absorbed more glucose and bile acid than did HM. The glucose transport of HM and HM-D against dialysis membrane showed 77% and 68% for 4h, respectively. After 24h, bile acid transport of HM and HM -D showed 65% and 62.3%, respectively. The HM and HM-D produced 217.8 mM and 264.0mM of SCFA, respectively. The production of butyric acid in HM-D (32.7mM) showed higher than that of HM (26.9mM). The addition of D-factor to HM increased the physiological function of dietary fiber through the glucose and bile acid absorption and production of SCFA.