• Biotechnology and Bioprocess Engineering:BBE
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• v.9 no.4
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• pp.245-251
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• 2004

The fungal species of Rhizopus oryzae 2062 has the capacity to carry out a single stage fermentation process for lactic acid production from potato starch wastewater. Starch hydrolysis, reducing sugar accumulation, biomass formation, and lactic acid production were affected with variations in pH, temperature, and starch source and concentration. A growth condition with starch concentration approximately 20 g/ L at pH 6.0 and 30$^{\circ}C$ was favourable for starch fermentation, resulting in a lactic acid yield of 78.3%∼85.5% associated with 1.5∼2.0 g/L fungal biomass produced in 36 h of fermentation.

• Applied Biological Chemistry
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• v.27 no.1
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• pp.52-54
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• 1984

Ethanol fermentation from the chemically gelatinized starchy material was examined. The critical concentration of sodium hydroxide solution for gelatinization was dependent on the species of starch; 0.4M for potato and 0.6M for tapioca at room temperature. For alcohol fermention the starchy material was gelatinized by addition of sodium hydroxide solution, neutralized by sulfuric acid, and then yeast was added. The amount of $CO_2$ evolved during ethanol fermentation indicates that non-fermentable material was not produced from the starch by chemical gelatinization. In ethanol fermentation of potato and tapioca starch no significant difference was observed between the thermal and the chemical gelatinization.

• The Korean Journal of Food And Nutrition
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• v.3 no.1
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• pp.1-8
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• 1990

Experiments were performed using sweet potato starch-wheat composite flours to study the rheology and baking properties of bread with composite flours and to test sensory characteristics. Doughs were prepared from mixtures containing wheat flour and 10, 20, and 30% of sweet potato starch(SPS). Standard methods were used to evaluate the rheology and characteristics of wheat composite flour.

• Korean Journal of Food Science and Technology
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• v.25 no.6
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• pp.747-752
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• 1993

A curd yogurt was prepared from milk added with skim milk powder or four kinds of starch such as rice starch, wheat starch, corn starch and potato starch. The effects of starch addition at 2%(w/v) level on acid production by lactic acid bacteria in milk was investigated. The effects of starch addition on quality of curd yogurt in terms of apparent viscosity, sensory property and volatile aroma compounds were also examined. Addition of starch markedly stimulated the acid production by lactic acid bacteria. Among four organisms tested, Lactobacillus jugurti produced the highest amount of acid. Apparent viscosity of curd yogurt added with starch was significantly higher than that of control. Curd yogurt fermented with L. jugurti showed pseudoplastic and thixotropic characteristics. Sensory property of curd yogurt added with corn starch or rice starch was evaluated as slightly better than reference sample, but that with potato starch was evaluated as the worst among all samples. Acetaldehyde, acetone, ethanol and butanol were detected by gas chromatographic analysis.

• Applied Biological Chemistry
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• v.35 no.5
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• pp.404-409
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• 1992

Hydroxypropylated starches and acetylated starches were prepared by reaction of potato starch with propylene oxide and acetic anhydride, respectively and then degree of retrogradation and swelling power were investigated in different pHs and temperature. The extent of retrogradation determined by glucoamylase method during freeze-thaw treatment and storage in low temperature $(0{\sim}5^{\circ}C)$ showed that modified potato starches were slowly retrograded as the increase of degree of substitution. The order of the retrogradation tendencies in different pHs were pH 4>pH 6>pH 8>pH 10. Retrogradation of hydroxypropylated potato starches were less than that of acetylated potato starches. Swelling power of starches were influenced more by the temperature than by the pH. The order of the swelling power tendencies in different pHs were pH 10>pH 2>pH 8>pH 4>pH 6.

• Korean journal of food and cookery science
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• v.5 no.1
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• pp.53-62
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• 1989

Granular shapes and size, physicochemical properties and gelatinization properties of potato starches from Irish cobber (the dry type), Dejima (the moist type), Shepody and Superior were investigated. The starch granule was round or oval and the size of Irish cobbler and Shepody starch were $11~30\mu\textrm{m}$ and those of Superior and Dejima were$ 21~40\mu\textrm{m}$. Blue value, amylose content, relative crystallinity and density of Irish cobbler were the highest, but that of Dejima were the lowest. Water binding capacity, swelling power, transmittance. peak viscosity and breakdown of amylogram of Superior starch were the highest, but that of Irish cobbler starch were the lowest. Gelatinization temperature of DSC of Irish cobbler starch was the highest, but that of Superior starch was the lowest.

• Asian-Australasian Journal of Animal Sciences
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• v.24 no.11
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• pp.1615-1622
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• 2011

A factorial ($4{\times}2{\times}2$) experimental design was employed to determine apparent digestibilities of dry matter (DM), protein, lipid, energy and nitrogen-free extract (NFE) of the test diets containing either ${\alpha}$-potato starch (A-PS), ${\beta}$-potato starch (B-PS), ${\beta}$-corn starch (B-CS) or dextrin (DEX) as dietary carbohydrate energy for juvenile (average weight 30 g) and grower (average weight 300 g) rockfish reared at 13$^{\circ}C$ and 20$^{\circ}C$. Chromic oxide was used as an inert marker. Feces were collected by fecal collectors attached to rearing tanks from triplicate groups of juvenile and grower rockfish. Digestibilities of DM, energy and NFE of the test diets were significantly affected by dietary carbohydrate and water temperature (p<0.01), but not by fish size. DM digestibility of the fish fed the A-PS diet was significantly higher than that of fish fed other treatments, except for the DEX diet at 20$^{\circ}C$. DM digestibility of rockfish fed the B-CS diet was significantly lower than that of other diets. A similar pattern was observed in apparent digestibility of energy. NFE digestibility of fish fed the test diets was significantly affected by carbohydrate and significantly correlated to DM (r = 0.97, p<0.01) and energy (r = 0.99, p<0.01) digestibilities, regardless of water temperature and fish size. NFE digestibility of the fish fed the ${\beta}$-starch diets was relatively lower compared to that of the ${\alpha}$-starch diets, and ranged from 35 to 43% and 20 to 27% for B-PS and B-CS, respectively. The present findings indicate that carbohydrate and water temperature significantly affected digestibilities of dry matter, energy and nitrogen-free extract of rockfish. Among dietary carbohydrates, ${\alpha}$-potato starch could be effectively used as dietary carbohydrate energy for rockfish at 13$^{\circ}C$ and 20$^{\circ}C$.

• Korean Journal of Agricultural Science
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• v.18 no.1
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• pp.41-48
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• 1991

Rheological properties of gelatinized potato starch were investigated with Brookfield wide-gap viscometer at various conditions. The gelatinized potato starch at 3-7% showed a pseudoplastic behavior with yield stress, and presented thixotropic properties with time-dependent structural decays. The consistency index and yield stress of gelatinized starch were proportional to starch concentration but inversely proportional to measurement temperature, and the flow behavior index did not show constant relationship. The consistency index and yield stress of the gelatinized starch on addition of phosphate decreased as the flow behavior index increased. The values of activation energy at initial and equilibrium were 1.52 kcal/g.mole and 127 kcal/g.mole, respectively.

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.151-155
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• 2005

Recently, systems biology has been increasingly applied to gain insights into the complexity of living organisms. Many inaccessible biological information and hidden evidences fur example flux distribution of the metabolites are simply revealed by investigation of artificial cell behaviors. Most bio-models are models of single cell organisms that cannot handle the multi-cellular organisms like plants. Herein, a structured and multi-cellular model of potato was developed to comprehend the root starch biosynthesis. On the basis of simplest plant cell biology, a potato structured model on the platform of Berkley Madonna was divided into three parts: photosynthetic (leaf), non-photosynthetic (tuber) and transportation (phloem) cells. The model of starch biosynthesis begins with the fixation of CO$_2$ from atmosphere to the Calvin cycle. Passing through a series of reactions, triose phosphate from Calvin cycle is converted to sucrose which is transported to sink cells and is eventually formed the amylose and amylopectin (starch constituents). After validating the model with data from a number of literatures, the results show that the structured model is a good representative of the studied system. The result of triose phosphate (DHAP and GAP) elevation due to lessening the aldolase activity is an illustration of the validation. Furthermore, the representative model was used to gain more understanding of starch production process such as the effect of CO$_2$ uptake on qualitative and quantitative aspects of starch biosynthesis.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1215-1221
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• 2007

Three Holstein steers fitted with ruminal and duodenal cannulae were fed grass silage-based diets supplemented with potato pulp silage as a substitute for rolled corn at levels of 0%, 50% and 100% on a DM basis in a $3{\times}3$ Latin square design to investigate the effect of potato pulp silage on nitrogen (N) utilization in ruminants. Organic matter (OM) intake, and rumen and total tract digestibilities did not differ among treatment diets. Rumen and post-rumen starch digestibilities were similar among treatments, although starch intake decreased (p<0.01) with potato pulp supplementation. There were no significant differences (p>0.05) in ruminal N utilization and non-ammonia N supply to the duodenum of steers fed grass silage supplemented with potato pulp silage as a substitute for rolled corn. There were no treatment differences (p>0.05) in rumen pH, volatile fatty acid (VFA) concentration or the molar percentages of acetate and propionate. The ammonia-N concentration in rumen fluid tended to decrease (p<0.1) when rolled corn was substituted with potato pulp silage. Ether extract intake and post-ruminal digestibility significantly (p<0.01) decreased in steers fed diets containing potato pulp silage. Concentrations of total cholesterol and phospholipids in serum markedly decreased (p<0.01) with potato pulp silage supplementation without adversely affecting liver function. These data suggested that potato pulp silage has a similar value as rolled corn as an energy source for rumen microorganisms.