• Korean Journal of Fisheries and Aquatic Sciences
• /
• v.32 no.5
• /
• pp.556-562
• /
• 1999

The increasing price of surimi has affected the economical benefits of surimi based food industry, To maintain gel strength in low grade surimi, the optimum formulation adding functional proteins to low grade surimi is required. The objective of this study was to develop the optimum formulation of ingredients in making gels in low grade surimi on the addition of functional non-muscle proteins to low grade surmi by measuring rheological properties of the gels. The rheological qualities of the cooked gels made with A and RA grade surimi on the effects of adding five kinds of starches (potato, wheat, waxy maize, corn and modified corn) and four kinds of functional proteins (bovine plasma protein, dehydrated egg white, soy protein isolate and whey protein concentrate) to the gels were evaluated, The gel styengths at cooking with A and RA grade surimi were decreased with increasing the added starches. The kind of starches added affected little the gel strengths in Rh grade surimi, while potato and corn starches decreased at the least in gel strengths of the gel made with A grade surimi with increasing the concentration of starches. The bovine plasma protein (BPP) significantly increased the gel strength, especially in RA grade surimi, but BPP decreased the whiteness of the gel. Therefore, the optimum content of BPP was up to $2\%$ because of the whiteness of the gels in RA grade surimi, The optimum formulation for the gel with RA grade surimi to satisfy the gel strength of 1000$\times$g and $78\%$ moisture was $40.9\%$ surimi, $9.1\%$ dehydrated egg white (DEW) and $0.9\%$ starch, while that with A grade surimi under the same condition was $37.9\%$ surimi, $6.6\%$ DEW and $3,4\%$ starch.

• Korean journal of food and cookery science
• /
• v.18 no.2
• /
• pp.200-205
• /
• 2002

Corn starch was modified by the oxidation with sodium hypochlorite(NaOCl) and the changes in the distribution of molecular weight were examined. Corn starch was oxidized with 0.25, 0.5, 0.75, 1.0, and 1.5% active Cl/g of starch at pH 7.0 and 25$^{\circ}C$ for 10 min. Oxidation of corn starch caused a change in the molecular weight distribution of amylopectin. The fraction of highest molecular weight in native starch decreased gradually and the fraction of lower molecular weight increased with increasing oxidation. Also, λ$\sub$max/ and iodine binding capacities of oxidized starches decreased and the soluble carbohydrate content increased by oxidation. The differential scanning calorimetric results of oxidized starches showed that the temperature and enthalpies of gelatinization were not changed by oxidation; however, the more the starch was oxidized, the greater the extent of retrogradation.

• Korean Journal of Food Science and Technology
• /
• v.28 no.3
• /
• pp.514-520
• /
• 1996

The purpose of this study was to develop the production technology of modified starch. Corn starches were gamma irradiated at 0-110 kGy and the effect of irradiation dose levels on the physicochemical properties of corn starches were investigated. Blue value linearly decreased, while alkali number and solubility markedly increased as irradiation dose levels were increased. The optical transmittance increased as applied irradiation dose levels were increased in the temperature range of $65-95^{\circ}C.$ Water binding capacity and swelling power showed maximum value at 30 and 10 kGy, respectively and they tended to decrease thereafter. Gelatinization viscosity of the gamma irradiated starch considerably decreased as compared to that of the non-irradiated starch. Irradiation at 110kGy resulted in a marked reduction of peak viscosity and cooling viscosity at $30^{\circ}C$ by 100 and 300 times, respectively. The physicochemical properties of corn starch irradiated at 30 kGy were similar to those of commercial acid-modified starch, while those of corn starch irradiated at 100 kGy were similar to those if oxidized starch.

• Journal of the East Asian Society of Dietary Life
• /
• v.9 no.4
• /
• pp.452-460
• /
• 1999

This study was conducted in order to investigate the quality characteristics of Salku Pyun which was made by using mungbean, potato, sweet potato and corn starches. The pH of salku juice was 3.45 to 3.50 and the brix of that was 7.0%. The water content and water activity of salku pyun with potato starch was highest. The result of sensory evaluation showed that appearance, flavor, overall quality were highest in the Salku Pyun made with potato starch while texture, taste were highest in the Salku Pyun made with mungbean starch. Mechanical properties of salku pyun with mungbean starch was significantly higher in adhesiveness, hardness, chewiness. Texture of sensory evaluation were positively correlated with springiness, hardness, and chewiness of mechanical measurement. The factors which affect the overall quality on sensory evaluation were texture quality, taste quality, hardness, color and springiness.

• Food Science and Biotechnology
• /
• v.17 no.4
• /
• pp.755-760
• /
• 2008

The aim of this study was to produce resistant starch preparations from acid-modified com starches prepared at various hydrolysis levels (0.5-4.0 hr). Effect of autoclaving cycles on resistant starch (RS) formation was investigated. Molecular weight distribution, pasting and functional properties of acid-modified com starches were determined. For RS formation native and acid-modified starch samples were gelatinized and autoclaved (1 or 2 cycles). While native and acid-modified starches did not contain any RS, the levels increased to 9.0-13.5% as a result of storage at $95^{\circ}C$ after first autoclaving cycle. Second autoclaving cycle together with storage at $95^{\circ}C$ brought final RS contents of the samples incubated at 4 and $95^{\circ}C$ after the first cycle to comparable level. As acid modification level increased, the amount of high molecular weight fractions decreased, resulting in significant decreases in viscosities (p<0.05). The samples produced in this study had low emulsion stability and capacity values.

• Korean journal of food and cookery science
• /
• v.4 no.1
• /
• pp.1-8
• /
• 1988

The physicochemical properties and gel-forming properties of corn & red bean crude starches were investigated. The results were as follows: 1. The shape of corn crude starch granule was polygonal and the mean value of minor axis and major axis were $11.5\mu\textrm{m}$ and $14.9\mu\textrm{m}$, respectively. In the meantime, the shape of red bean crude starch granule was oval and the mean value of minor axis and major axis were $22.3\mu\textrm{m}$ and $31.4\mu\textrm{m}$. 2. Amylose content of corn and red bean refined starch were 16.52 and 43.61% respectively. 3. Blue value of corn and red bean crude starch were 0.099 and 0.842, respectively. 4. Amylose of corn had molecular weight of 107,000 and degree of polymerization of 660. Amylopectin had degree of branching of 6.9 per 100 glucose units and glucose units of 14.6 persegment of amylopectin. Amylose of red bean had molecular weight of 118,000 and amylopectin had degree of branching of 5.2. 5. Water binding capacities of corn and red bean starch were 238.5 and 284.8. 6. Both swelling powers of corn and red bean starch were increased rapidly from $70^{\circ}C$ to $90^{\circ}C$. 7, Gelatinization of corn and red bean were 75.6 and $61.8^{\circ}C$. 8. Brabender hot-paste viscosities of corn at 6% and 8% showed the similar amylogrm patterns with peak viscosity. And red bean had no peak viscosity. 9. The difference of sensory characteristics for ‘Mook’ and kidney bean & red bean starch gels was significant.

• Korean Journal of Food Science and Technology
• /
• v.27 no.4
• /
• pp.625-630
• /
• 1995

In order to know the effects of hot-water extracts of starches on gel formation and gel properties, some physicochemical properties and molecular distribution of the extracts were measured. Also, after acid-hydrolysis of starch gels and extract gels, extent of hydrolysis and $\overline{D.P}._n$, and molecular distribution of hydrolysis-residue were measured. Extraction ratio of grain starches (buckwheat, corn, rice, and wheat) were $4.0{\sim}6.6%$. The ratio of acorn and mungbean starches were 11.7 and 13.5%, respectively. Iodine affinity of the extracts was $17.2{\sim}17.7%$ in starches using for Mook, SM(acorn, buckwheat, and mungbean), $13.7{\sim}14.9%$ in starches not using for Mook, SNM(corn, rice, and wheat). Blue value was also higher in SM than in SNM. $\overline{D.P}._n$. of extracts of SM were bigger than those of SNM. In molecular distribution experiment, amylopectin fraction was not found from the extracts except rice starch extract. The extent of acid hydrolysis of the starch gels were $70{\sim}84%$ after 60 days, and the extent of the extract gels were $22{\sim}35%$. The extent of hydrolysis of starch gels and extract gels made with SM were lower than those of SNM.

• Preventive Nutrition and Food Science
• /
• v.4 no.3
• /
• pp.175-179
• /
• 1999

To develop a production method for modified starches with less pollution, pH adjustment and gamma irradiation were applied to commerical corn starch. Blue values were significantly decreased , while alkali number, optical transmittance and solubility markedly increased when gamma irradiation was applied to pH 2 adjusted corn starch. Water binding capacity and swelling power at pH 5 were the highest among the samples. Gelatinization viscosity was considerably affected by gamma irradiation and pH of the starch. Gamma irradiation of pH 2 adjusted starch showed the lowest peak viscosity and the best cooling stability among the tested samples . Therefore, the production of modified starch with low viscosity as well as with sufficient viscosity stability seems feasible by controlling the pH of the starch and gamma irrdiation.

• Korean Journal of Food Science and Technology
• /
• v.24 no.1
• /
• pp.70-73
• /
• 1992

Gelatinization behaviour and gel properties of corn starch modified either by hydroxypropylation only or by cross-linking and hydroxypropylation were investigated. Gelatinization temperature of corn starch decreased greatly by hydroxypropylation, but increased slightly by cross-linking with epichlorohydrin. The treatment of both hydroxypropylation and cross-linking lowered the gelatinization temperature, although it was not significantly different from that of hydroxypropylated corn starch. The swelling power of the corn starch was reduced and gel strength was increased by both modifications. The results suggested that the gelatinization behaviour and gel properties of corn starch could be improved by both cross-linking and hydroxypropylation.

• Journal of the East Asian Society of Dietary Life
• /
• v.25 no.3
• /
• pp.474-483
• /
• 2015

The textural properties of breads containing midified starches such as pregelatinized waxy corn starch, acetylated potato starch and hydroxypropylated tapioca starch, were investigated to determine the optimum addition level of modified starches. Effects of modified starches on dough properties were investigated through a farinogram and amylogram based on the different additional levels of modified starches (3%, 6%, 9%, 12% and 15% of flour content). Moisture contents and firmness values were measured to investigate the degree of retrogradation at 0 h, 36 h and 72 h after production. The levels of moisture contents were highest upon addition of pregelatinized waxy corn starch followed by acetylated potato starch and lowest upon addition of hydroxypropylated tapioca starch. Overall, higher moisture contents resulted in lower firmness levels. The preference scores by type of modified starch were highest upon addition of 9% hydroxypropylated tapioca starch, 3% pregelatinized waxy corn starch, and 6% acetylated potato starch, respectively. Preference scores were significantly correlated with textural properties such as volume, absorption, stability and weakness (p<0.01).