• Korean journal of food and cookery science
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• v.21 no.1 s.85
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• pp.24-32
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• 2005

Changes in apple slices during cold storage were investigated by evaluating the physical properties such as degree of browning and compression force. Chemical properties such as PPO activity and total phenol contents were also determined and sensory evaluation was carried out. The correlation analysis between browning parameters was conducted. Degree of browning was increased in the order of fresh apple slice, water-dipped apple slice, $0.5\%$ ascorbic acid solution-dipped apple slice and CP(caramelization product) from sucrose-dipped apple slice. PPO activity was increased in the order of fresh apple slice, water-dipped apple slice, $0.5\%$ ascorbic acid solution-dipped apple slice and CP(caramelization product) from sucrose-dipped apple slice. Amongst several treatments, CP from sucrose-dipped apple slice showed the lowest degree of browning and PPO activity. Total phenol contents were decreased from 60 to 56.2 mg and from 59.6 to 56.0 mg in fresh apple slice and water-dipped apple slice, respectively, but CP from sucrose-dipped apple slice and $0.5\%$ ascorbic acid solution-dipped apple slice were increased from 51.9 to 52.8 mg and from 54.1 to 54.4 mg, respectively, showing the smallest changes when compared with fresh apple slice and water-dipped apple slice. Compression forces of apple slices during cold storage were decreased in the order of fresh apple slice, water-dipped apple slice, $0.5\%$ ascorbic acid solution-dipped apple slice and CP from sucrose-dipped apple slice. In sensory evaluation of apple slices during cold storage, CP from sucrose-dipped apple slice had higher score than the other treatments. In addition, a significant correlation was observed among degree of browning, PPO activity and phenol content. Therefore, CP from sucrose-dipped apple slice seems to be effective in controlling of enzymatic browning during cold storage. In addition, CP from sucrose-dipped apple slice seems to be effective on other several factors. These results suggest that CP from sucrose should be a potential source for controlling enzymatic browning during storage of vegetables and fruits.

• Journal of the Korean Society of Food Culture
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• v.23 no.4
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• pp.489-498
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• 2008

The objectives of this study were to provide fundamental information on how individual phenolic compounds form on the inside of apple slices during cold storage, the changes in the content of four types of phenols, ingredient variation of individual phenolic compounds and the influence of phenolic compounds on enzymatic browning. This study measured the changes in the content of soluble solids, pH and vitamin C in order to investigate the correlations between these variables. HD and FA were the main phenolic compounds found in the apple slices, and HD was the most prevalent phenol. Furthermore, comparison of the CG and EP content revealed that there were more CGs than EPs. The phenol content tended to decrease considerably in the fresh apple slices and water-dipped apple slices but only slightly in the CP from sucrose-dipped apple slices and 0.5% ascorbic acid solution-dipped apple slices. The degree of browning increased in the following order: fresh apple slices, water-dipped apple slices, 0.5% ascorbic acid solution-dipped apple slices and CP from sucrose-dipped apple slices. The vitamin C content tended to decrease in the fresh apple slices, water-dipped apple slices, 0.5% ascorbic acid solution-dipped apple slices and CP from sucrose-dipped apple slices. The pH tended to increase in all sample groups, but the pH of the water-dipped apple slices was lower than that of the comparison group. The CP from sucrose-dipped apple slices had the lowest value of pH. The change in soluble solids tended to increase in all treatment groups, but this increase was less in the CP from sucrose-dipped apple slice. Correlation analysis revealed a high degree of correlation between browning and chlorogenic acid content. The results of the present study show that, when stored in the fridge, the change in phenol ingredient content in apple slices influences the browning of the slices. The results also showed that HD and FA were the main phenolic compounds, while CG was shown to have the greatest influence on browning.

• Journal of the Korean Society of Food Science and Nutrition
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• v.40 no.6
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• pp.848-852
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• 2011

The aim of our study was to develop drying process of apple slice. Quality characteristics of apple slices dried by hot-air and freeze drying after osmotic dehydration was investigated in different sucrose solution (20, 40, $60^{\circ}Brix$) and steeping time (2, 4, 8 hours). The weight of apple slice before and after osmotic dehydration was measured for characteristic of mass transfer. Consequently, osmotic dehydration increases weight reduction, water loss and solid gain of apple slice as the concentration of the sucrose solution and steeping time increased. Moisture contents of apples slices dried hot-air and freeze were about 3 to 7%. Hunter color L, a, b value was lower than non-treatment to osmotic dehydration of apple slice. In hot-air drying, L value decreased as the concentration of the sucrose solution and steeping time increased. The hardness increased as the concentration of the sucrose solution and steeping time increased. Contents of monosaccharide (glucose, fructose) decrease by osmotic dehydration but sucrose increased. In comparison with hot-air drying, freeze drying was high in contents of free sugar.

• Agricultural and Biosystems Engineering
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• v.2 no.2
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• pp.59-62
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• 2001

The starch content of apples, which is related to the maturity and ripeness, was quantified by using a computer vision system. The stained area was measured by image analysis when an apple slice was stained with KI/I$_2$ solution. The ratio of stained area of the apple slice to its whole area, so called the starch index, was defined as an indicator of the starch content. When Tsugaru apples were manually sorted into immature, turing and mature groups, their starch indices were 0.374, 0.312 and 0.129, respectively. The starch index had relationships to various physicochemical properties of Tsugaru apples. At the statistically significant level of 0.1%, it was correlated with the pH value, bio-yield force, rupture force and color of intact and skin-removed apples. At the 1% significant level, it had the correlation with the density and moisture content.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2000.11b
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• pp.204-209
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• 2000

At harvest, the starch contents of apples, which were related to their maturity, were quantified by using image analysis. The stained area was measured by a computer vision system when an apple slice was stained with KI/I$_2$ solution. The stained area ratio of the stained area of the apple slice to its whole area, or the starch index, was defined as an indicator of starch content. When Tsugaru apples were manually sorted into immature, turning and mature groups, their starch indices were 0.374, 0.312 and 0.129, respectively. Meanwhile, the starch index had correlation to various physicochemical properties of Tsugaru apples. At the statistically significant level of 0.1 %, it was correlated with the pH value, bio-yield force, rupture force and color of intact and skin-removed apples. At the 1 ％ significant level, it had the correlation with the density and moisture content.

• Proceedings of the Korean Society of Plant Pathology Conference
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• 2003.10a
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• pp.129.2-130
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• 2003

Tomato soil pathogens(Phythopthora spp.) analyed high rates in series culture soil and existed in culture parts. To make a diagnosis of Phythopthora sp. and Its concentration, potato slices were manufactured to a round shape(2.5cm) or retangular form(1x4cm). and then, The potato slices dipped into diagnostic reagents with an antibiotic substance for 2∼4hours. Potato slices treated with a few reagents varied into 15cm depths in innoculated soils for 24hrs. Mycelium of the Phytophthora root rot fungus, Phythopthora capsici, were produced easily on potato slice. We collected many potato slice samples on diseased fields in various area. After storage of 24hrs in 20$^{\circ}C$ incubator, White mycelium of Phythopthora sp. formed on potato slice surface. Dilute concentrations of Phythopthora sp. was detected very low contents(1${\times}$10$^1$sporangia/g). But expressing Phythopthora root rots on potato slice did not developed larger lesions upon storage time in room temperature. These results suggest that the use of potato slice in a series of soil cultural system may still serve as efficient means of diagnosis of Phythopthora root rots in the absence of control measures.

• Proceedings of the Korean Society of Near Infrared Spectroscopy Conference
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• 2001.06a
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• pp.1529-1529
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• 2001

The watercore in apple is very important factor in storage and sorting of fruit. Most consumers tend to prefer the apple included watercore in immediately after harvest, however the watercore causes fruit flesh to brown during storage and lose the worth after all. But it is practically impossible to judge to the naked eye whether an apple has watercore or not. Therefore, the rapid, accurate and non-destructive analysis method for discrimination of watercore should be settled without delay. In this study we attempted the discrimination and quantitative analysis of watercore in apple fruit using near-infrared transmittance spectroscopy ‘Fuji’ apple fruits produced in Kyungpook of Korea was used in this experiment. The watercore content in apple was evaluated by graphic treatment of culled slice sections(10 mm). NIR transmittance spectra were collected over the 500 to 1000 nm spectral region with a spectrometer (Sentronic Co., Germany). The calibration models were carried out by partial least squares (PLS) analysis between NIR spectra data of apples and chemical data of watercore content. The spectra were different in absorbance between apple included watercore and not included one. Apple included watercore had higher absorption band than sample not included one at 732 and 820 nm. The calibration model seems to be accurate to predict the watercore content in apple fruit, the correlation coefficient (R) and root mean square error of prediction (RMSEP) were 0.99 and 0.93%, respectively. This result indicates that the PLSR calibration model by using NIR transmittance spectroscopy could be used for discrimination of watercore in apple fruit.

• Food Science and Preservation
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• v.17 no.2
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• pp.256-260
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• 2010

We investigated changes in the chemical composition of apple slices after pretreatment with supercritical $CO_2$. Total phenolic levels increased with increasing temperature, although the concentrations were lower in pretreated material than in fresh or untreated slices. The levels of vitamin C and malic acid in pretreated slices were also lower than in untreated or fresh apple slices. Little difference was evident among various pretreatmentconditions. It was found that supercritical $CO_2$ served not as a solvent but rather as a means of tissue compression. Supercritical $CO_2$ compressed the apple slices, causing juice to be extruded. The juice disappeared when the supercritical $CO_2$ pressure was released.

• Journal of Biomedical Engineering Research
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• v.6 no.2
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• pp.15-22
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• 1985

We have developed a microprogramir!able signal processor for real-time ultrasonic signal processing. Processing speed was increased by the parallelism in horizontal microprogram using 104bits microcode and the Pipelined architecture. Control unit of the signal processor was designed by microprogrammed architec- ture and writable control store (WCS) which was interfaced with host computer, APPLE- ll . This enables the processor to develop and simulate various digital signal processing algorithms. The performance of the processor was evaluated by the Fast Fourier Transform (FFT) program. The execution time to perform 16 bit 1024 points complex FF7, radix-2 DIT algorithm, was about 175 msec with IMHz master Clock. We can use this processor to Bevelop more efficient signal processing algorithms on the biological signal processing.

• Food Science and Preservation
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• v.18 no.4
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• pp.584-589
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• 2011

This study was conducted to investigate the effects of Taraxacum platycarpum and Chrysanthemum indicum extracts on the browning of apple slices. The inhibition of the PPO activities, total phenolic contents, and DPPH free-radical-scavenging activities was measured from water and from the 80% EtOH extracts of Taraxacum platycarpum and Chrysanthemum indicum as natural antibrowning agents. Apples were cut into 15-mm-thick slices, and each slice was dipped for 1 min in different treatment solutions (1% Taraxacum platycarpum and Chrysanthemum indicum extracts, 1% citric acid) and was stored at room temperature. The inhibition of the PPO activity in the Chrysanthemumin indicum extract was better than that in the Taraxacum platycarpum extract. The highest DPPH free-radical-scavenging activity (76.10%) was found in the 80% EtOH extract of Chrysanthemum indicum. After 24 h, the ${\Delta}E$ value of the apple slices that were treated in the 80% EtOH extract of Chrysanthemum indicum was at the lowest level (2.22). The total phenolic content was 94.07 mg/g, and the total flavonoid content was 102.60 mg/g, in the 80% EtOH extract of Chrysanthemum indicum. The antibrowning effect of Chrysanthemum indicum was higher than that of Taraxacum platycarpum in the apple slices.