• Applied Biological Chemistry
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• v.28 no.3
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• pp.156-161
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• 1985

Physicochemical properties and characteristics on lintnerization of sweet potato starches from Wouki(the dry type), Shinmi(the intermediate type) ana Chunmi(the moist type) were investigated. Swelling and gelatinization curves of these starches showed a two-stage process. Swelling powers of starches were higher in order of Shinmi, Chunmi and Wonki over a range of temperatures. Amylose content of Wonki was higher than those of other two. Hydrolytic patterns of three starches with 2.2 N HCI at $35^{\circ}C$ showed two distinct stages. Hydrolysis extents of Wonki starch were lower than those of Shinmi and Chunmi starches. X-ray diffraction patterns of native and lintnerized starches were the Ca crystalline type. The relative crystallinities of these starches were higher in order of Worki, Chunmi and Shinmi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.5
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• pp.596-602
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• 1993

The Characteristics of Shinsunchalbyeo(Japonica) and Hangangchalbyeo($J{\times}Idica$) starches including physicochemical properties, differential scanning calorimetry(DSC) and enzymatic digestion of lintnerized starches were investigated. Degree of hydrolysis of Hangangchalbyeo starch with 2.2N HCI for 48hr was higher than that of shinsunchalbyeo starch. Absorbance at ${\lambda}_{max}$ 680nm, and ${\lambda}_{max}$ of iodine stained starch decreased upon acid treatment. But water binding capacity, swelling power and solubility considerably increased as hydrolysis progressed. Relative crystallinity of two starches increased with acid treatment, and that of Shinsunchalbyeo starch was higher than that of Hangangchalbyeo starch. DSC data continuously decreased for lintnerization periods, and those of Shinsunchalbyeo starch. DSC data continuously decreased for lintnerization periods, and those of Shinsunchalbyeo starch have higher than those of Hangangchalbyeo starch. The onset temperature of starch by DSC continuously decreased by treatment, but conclusion temperature increased until 24hr and then decreased. The enthalpy for gelatinization decreased for both starches. Degree of hydrolysis of lintnerized Shinsunchalbyeo starch with glucoamylase was slightly higher than that of Hangangchalbyeo starch.

• Applied Biological Chemistry
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• v.35 no.3
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• pp.196-201
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• 1992

Characteristics on lintnerization of dry type (Suwon 147) and moist type (Hwangmi) sweet potato starches were investigated. Chain distribution of lintnerized starches was also studied by debranching with pullulanase. Hydrolytic patterns of two starches showed two distinct stages and hydrolysis extents of Suwon 147 starch were lower than those of Hwangmi starch. The relative crystallinities of Suwon 147 starches were higher than those of Hwangmi starch. The elution profiles of lintnerized starches were composed of two peaks about degree of polymerization (DP) 25 and DP 15. The elution profiles of debranched samples showed only one peak about DP 15 and peak DP of Suwon 147 lintnerized starch was higher than that of Hwangmi.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1086-1090
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• 1997

Morphological properties on lintnerized maize starches with different amylose content were investigated. With increasing the lintnerization periods and decreasing the amylose content, hydrolysis rate was increased. As amylose content of starch was increased, the degree of damage with acid treatment was decreased by SEM. With increasing hydrolysis, iodine affinity, apparent amylose content and ${\lambda}_{max}$ of lintnerized starches were decreased. Water binding capacities of lintnerized starches were higher than those of native starches.

• Applied Biological Chemistry
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• v.40 no.5
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• pp.395-399
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• 1997

Lintnerization properties and yield of enzyme-resistant starch in maize starches with different amylose content were investigated. Hydrolytic patterns of starches showed two distinct stages. With decreasing the amylose content, hydrolysis extents of starch increased. X-ray diffraction patterns of Amloca, PFP and commercial maize starch were the A crystalline type, and those of Amaizo 5 and Amylomaize VII were the B crystalline type. As acid hydrolysis time increased, the relative crystallinity of starches increased. After heating-cooling treatment was repeated up to 4 times, the yield of RS increased with increasing the amylose content. The yields of RS in lintnerzed maize starches decreased with acid treatment.

• Korean Journal of Food Science and Technology
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• v.23 no.1
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• pp.62-67
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• 1991

The characteristics of Tongjinbyeo(Japonica) and Samgangbyeo($J{\times}Indica$) rice starches including physicochemical properties, differential scanning calorimetry and enzymatic digestion of lintnerized starches were investigated. Degree of hydrolysis of Tongjinbyeo starch with 2.2N HCI for 48 hr was higher than that of Samgangbyeo starch. Apparent first order reaction of starches was slow reaction for first period, and fast reaction second period on the datum point of acid treatment 24 hr. Absorbance at ${\lambda}_{max}$ and 680 nm, and ${\lambda}_{max}$ of iodine stained starch and amylose content decreased upon acid treatment. But water binding capacity, swelling power and solubility considerably increased as hydrolysis progressed. Relative crystallinity of two starches increased with acid treatment, and that of Tongjinbyeo starch was higher than that of Samgangbyeo starch. Differential scanning colorimetry(DSC) data continuously decreased for lintnerization periods, and those of Tongjinbyeo starch have higher than those of Samgangbyeo starch. The onset temperature of starch by DSC continuously decreased by treatment, but conclusion temperature increased until 24 hr and then decreased. The enthalpy for gelatinization decreased for both starches. Degree of hydrolysis of lintnerized Tongjinbyeo starch with glucoamylase was slightly higher than that of Samgangbyeo starch.

• Applied Biological Chemistry
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• v.31 no.3
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• pp.249-254
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• 1988

Physicochemical properties of starches from the rices of Akibare, Samgang and Mahatma and hardness of the cooked rice were examined Water binding capacity and amylose content were heigher in Samgang. Peak viscosity and breakdown were heigher in order of Akibare, Samgang and Mahatma, while consistency and set back were reverse order. Hydrolytic patterns of three starches with 2.2N HCl at $35^{\circ}C$ showed two distinct stages. Hydrolysis extent of Mahatma starch was lower than those of Akibare and Samgang starches. The relative crystallinities of these starches were heigher in order of Mahatma, Akibare and Samgang. Mahatma was more resistant to heat and acid treatments, lower in water binding capacity and harder when it was cooked.

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.876-881
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• 1997

The relationship between the molecular structure of acid-hydrolyzed rice starch and the retrogradation rate of starch gel was investigated. The molecular structure of starch was modified by acid hydrolysis with 1 N HCl at $35^{\circ}C$. The molecular weight of starch decreased as acid hydrolysis time was increased. At the early stage of hydrolysis up to 3 hr, the branching point of amylopectin was degraded and thereafter both ${\alpha}-1,4\;and\;{\alpha}-1,6$ linkages were hydrolyzed. The starch gel (50%) stored at $20^{\circ}C$ revealed that the rapid retrogradation occurred during 4 hr of storage which was more pronounced as the hydrolysis time increased. The degree of retrogradation of starch gels after 4 hr storage showed a linear relationship with the yield of hydrolyzate. These results suggested that the retrogradation of starch gel was accelerated by degradation of ${\alpha}-1,6$ linkages with acid.