• The Korean Journal of Food And Nutrition
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• v.30 no.1
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• pp.139-147
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• 2017

The objective of this study was to develop anti-browning agents for commercial ready-to-eat pear products, which are preferred not only to maintain the flavor, color and texture of pears, but also to increase consumers' preference. The sliced 'Shin-go (Niitaka)' pears were immersed in 5% and 10% oxidized starch, 1% citric acid, and 5% and 10% oxidized starch with addition of 0.1% sucralose for 3 minutes, and then they were packaged in vacuum sealed bags at $1^{\circ}C$ for 9 days. In order to evaluate the quality of packaged sliced pears, the quality index was determined in terms of color, firmness, soluble solids, and sensory quality. With the passage of storage time, no specific variation in firmness and soluble solids was observed. However, the ${\Delta}E$ value of the sliced pears treated with 5% oxidized starch solution was significantly lower than that of the other pears. Also, the Hunter L and b values of the sliced pears treated with 5% oxidized starch solution remained nearly constant from the beginning of storage. This observation shows that 5% oxidized starch solution was effective in reducing surface browning of sliced pears. Moreover, sliced pears treated with oxidized starch solution with addition of 0.1% sucralose were given an overall liking score which was slightly higher than that given to the other pears because of the sweetness of sucralose. In conclusion, 5% oxidized starch solution with addition of 0.1% sucralose was effective in reducing browning of sliced pears and in improving the taste of sliced pears.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.11-16
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• 1984

Rheological properties of waxy and non-waxy rice starch solutions were evaluated with a narrow gap rotational and Cannon Fenske viscometers. The gelatinized rice starch solutions containing 0.2-1.0% starch displayed pseudoplastic flow behavior. At higher starch level, degree of pseudoplasticity of waxy rice starch solutions increased, while that of non-waxy rice did not changed apparently. The consistency coefficient (K) of non-waxy rice starch solutions increased with increasing gelatinization temperature, but waxy rice starch solutions remained constant, and in alkaline aqueous solutions both of them showed increasing K values. The value of K increased exponentially with an increase in concentration. The effect of the temperature on the viscosity of the solutions followed Arrhenius' type equation, and the activation energies were in the range of 3.675-3.775 kcal/g-mol that were near to that of pure water. The changes of reduced viscosity with concentration were followed Huggin's equation and the values of intrinsic viscosity and interaction coefficient were 0.78-1.59 dl/g and 0.67-2.75, respectively.

• Food Science and Preservation
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• v.8 no.4
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• pp.434-441
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• 2001

The purpose of this research is the establishment of optimal processing and the quality improvement of confectionary analysis of the damaged starch content of flour. I studied the rheological and bread making properties of the dough containing different damaged starch content. I examined rheological and physico- chemical characteristic farinograph, extensograph and amylograph with DNS, CWRS and SW containing 6.5%, 8.2%, 9.0%, 9.0% and 10.5% of damaged starch. And I measured the hardness and specific volume and performed the functional survey by rheometer for quality control. In the amylogram, at the damaged starch content 9.5% at such the maximum viscosity was 900 B.U. the volume of bread fermention tolerance were increased. In addition, the extensegram after 135 min showed that maximum resistance of the dough were 570 B.U at the damaged starch contents of 9.5% and the bread had homogeneous air cells and internal structures at the damaged starch contents of 9.5% at which the area(A), resistance(R) and R/E value of the dough were highest.

• Journal of the Korean Society of Food Science and Nutrition
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• v.30 no.5
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• pp.865-869
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• 2001

Isolation and identification of the major bacteria causing spoilage of buckwheat starch jelly, and the effects of chitosan concentrations (0, 0.5, 1.0, 1.5, 2.0%) on shelf-life and quality of buckwheat starch jelly were investigated. Eight strains were isolated from spoiled buckwheat starch jelly and identified as Serratia liquefaciens and Staphylococus lentus. During storage of buckwheat starch jelly for 6 days at 18$^{\circ}C$, viable counts were lower at higher chitosan concentrations, especially at 1.5% and 2.0%. Water activity was less reduced at higher chitosan concentrations. Color L* value decreased, and a* values increased slightly with storage periods. In sensory evaluation, buckwheat starch jelly containng 1.0% chitosan was evaluated the best, with lower overall acceptability at higher chitosan concentrations. Buckwheat starch jelly containing 1.0% chitosan showed a longer shelf-life by 1~2 days than the control.

• Asian-Australasian Journal of Animal Sciences
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• v.30 no.6
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• pp.797-803
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• 2017

Objective: Effects of nitrogen supplementation associated with different levels of starch on voluntary intake, digestibility, and rumen and metabolic characteristics of cattle fed low-quality tropical forage (Brachiaria decumbens hay, 7.4% crude protein, CP) were evaluated using ruminal and abomasal cannulated steers. Methods: Five European${\times}$Zebu young bulls (186 kg body weight, BW) were distributed according to a $5{\times}5$ Latin square. The following treatments were evaluated: control, supplementation with 300 g CP/d (0:1), supplementation with 300 g starch/d and 300 g CP/d (1:1), supplementation with 600 g starch/d and 300 g CP/d (2:1), and supplementation with 900 g starch/d and 300 g CP/d (3:1). A mixture of nitrogenous compounds provided 1/3 from true protein (casein) and 2/3 from non-protein nitrogen (mixture of urea and ammonium sulphate, 9:1) was used as the nitrogen supplement. In order to supply energy a unique source of corn starch was used. Results: Supplements increased (p<0.05) dry matter intake, but did not affect (p>0.05) forage intake. There was a cubic effect (p<0.05) of starch on voluntary intake. This was attributed to the highest forage intake (g/kg BW) when using the 2:1 starch:CP ratio. Supplements increased (p<0.05) organic matter (OM) digestibility, but did not affect (p>0.05) neutral detergent fibre corrected for ash and protein (NDFap) digestibility. There was a positive linear effect (p<0.05) of the amount of starch supplemented on OM digestibility. Total NDFap digestibility was not affected (p>0.05) by the amount of supplemental starch. Ruminal ammonia nitrogen concentrations were higher (p<0.05) in supplemented animals, however, a negative linear effect (p<0.05) of amount of starch was observed. Supplements increased (p<0.05) the nitrogen balance (NB) and efficiency of nitrogen utilization. These effects were attributed to increased body anabolism, supported by higher (p<0.05) serum concentration of insulin-like growth factor 1. Increasing the amount of starch tended (p<0.06) to linearly increase the NB. In spite of this, there was a highest NB value for the 2:1 starch:CP ratio amongst the treatments with supplementation. Conclusion: Nitrogen supplementation in cattle fed low-quality tropical forage increases nitrogen retention in the animal's body. An additional supply of starch increases nitrogen retention by increasing energy availability for both rumen and animal metabolism.

• Food Science and Preservation
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• v.20 no.4
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• pp.539-545
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• 2013

Effects of RS4 type resistant corn starch on the quality characteristics of cookies were investigated by physicochemical, instrumental and sensory evaluation. The resistant starch was made by cross-linking of corn starch as following; corn starch slurry was annealed at pH 2.0 and $50^{\circ}C$ for 2 h followed by the cross-linking reaction. The cross-linking reaction was performed at $50^{\circ}C$ for 12 h in the presence of 1.2%/st.ds NaOH, 10%/st.ds sodium sulfate and 10%/st.ds of sodium trimetaphosphate (STMP)/sodium tripolyphosphate (STPP) mixture. Dietary fiber content of the resistant starch was estimated to be 73.8% by the AOAC method. For quality characteristics, dough pH decreased with the increase of the resistant starch content and spread factor decreased a little at 20% of the resistant starch. The moisture content and L value of cookies increased with the increase of the resistant starch content. However, the hardness and fracturability decreased with the increase of the resistant starch content. In the sensory evaluation, no significant differences were observed between the two cookies with or without the resistant starch. The results of this study suggest that the RS4 type resistant corn starch can be a good ingredient to increase dietary fiber content in cookies without changes of their qualities.

• Korean Journal of Food Science and Technology
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• v.15 no.2
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• pp.177-182
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• 1983

Direct conversion of starchy materials to single cell protein of Sporobolomyces holsaticus FRI Y-5 was investigated. Effect of yeast extract concentration on its cell growth showed that it could utilize more of starch in the medium containing 2.5 g/l of yeast extract. In case of jar fermentor culture, the specific growth rate and cell yield of Sp. holsaticus on soluble starch were calculated to be $0.14\;hr^{-1}$ and 0.425, respectively and its maximum cell concentration was 13.4 g/l. After 80 hr of incubation time, 45.96% of starch was consumed and 45.1% of relative blue value was decreased. Reducing sugars in the starch medium seemed to increase from 4.06 g/l to 6.08 g/l and then to decrease. During fermentor culture, pH of medium was almost not changed in the range of $pH\;7.0{\pm}0.5$. The optimal temperature and pH of Sp. holsaticus amylase activity were $40^{\circ}C$ and pH 7.5, respectively. It was shown from the effect of Tapioca starch concentration on the cell growth that the optimal concentration of Tapioca starch for Sp. holsaticus was lower than that of soluble starch. FRI Y-5 cells settled much slower than Sp. holsaticus IFO 1032 cells and the viscosity vs cell concentration relationship was related to be linear.

• Journal of the Korean Society of Food Science and Nutrition
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• v.37 no.10
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• pp.1251-1257
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• 2008

For the first 42 days, we made rats obese by feeding them potato starch instead of corn starch and after that we fed them transformed potato starch by 4 groups for 70 days. The 4 groups are GPS group, SPS group, EZ group and H40 groups and each were fed normal potato, small potato, enzyme treated potato, and acid treated potato starches, respectively. We determined body weight and feeding efficiency, lipid profiles in serum, lipid peroxidation in tissues and redox antioxidant system as GSH and GP-x in vivo. As a result, there was no difference in the increment of body weight in the groups of GPS, EZ and H40. Therefore EZ group showed lower body weight increment than other groups. While GPS group and SPS group did not show significant difference in blood glucose, cholesterol level, LDL-cholesterol and TC, and their measured values were lower than those of EZ and H40 groups. No significant difference was found in HDL-cholesterol level except for GPS group. Furthermore, when calculating atherogenic index (AI) by HDL-cholesterol and TC contents, H40 group showed higher measured value than other groups. When measuring the lipid peroxidation in serum, kidney and liver tissues, the serum lipid peroxidation in H40 group was higher than others. In the tissue of liver and kidney, EZ and H40 groups showed significantly lower contents than others. The content of GSH showed different tendency in each tissue, but the measured value of GP-x activity was lower in SPS group.

• Korean Journal of Food Science and Technology
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• v.21 no.6
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• pp.766-771
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• 1989

physicochemical properties of rice starch isolated from eight varieties were examined to evaluate the rice processing suitability The amylose contents of rice starch were varied with 16.7-29.7%, and IR 30, Godael, Aguja and Lengkwang varieties showed higher amylose content than the other varieties. The water binding capacity and blue value were in the range of 87.0 103.0 and 0.178-0.305, respectively. As the amylose content increased, the amylogram pasting temperature and the break down ratio increased, while the peak viscosity did not show any significant difference. The transmittance of 0.1% starch suspension slowly increased at $50^{\circ}C$ in the low-amylose content rice group, and rapidly increased at $65^{\circ}C$ in the high-amylose content rice group, but there were no differences above $75^{\circ}C$ among varieties. Also the low-amylose rice starch showed higher values in the swelling power and solubility. The hardness of the 30% rice starch gels was low in low-amylose one. During storage at $20^{\circ}C$ for 14 days, the increment of hardness was more slow in high-amylose one. The retrogradation velocity constant of rice starch gel by Avrami equation was the highest as 0.219 in Aguja variety.

• Food Science and Biotechnology
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• v.17 no.2
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• pp.234-240
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• 2008

The optimal conditions for the production of branched dextrin from com starch (CSBD) using branching enzyme (BE) were established by investigating the degree of retrogradation of the gelatinized starch. The physicochemical properties of CSBD prepared using the established process were evaluated. It was found that physicochemical properties of com starch were greatly modified by BE treatment. CSBD had a higher dextrose-equivalent value and water solubility than the corresponding control. On the other hand, the viscosities in gelatinized solution and amylose contents of CSBD were lower than those of the control. A high-performance size-exclusion chromatography/multiangle laser light scattering/retractive index (HPSEC/MALLS/RI) system showed that the average molecular weight of CSBD was lower than that of the control. The pasting viscosities of CSBD were stable during the entire temperature cycle. In general, the BE treatment resulted in the retrogradation during storage being lower for CSBD than for the control.