• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.44-44
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• 2017

The objective of this study was to evaluate firmness, and sweetness index (SI) of tomatoes (Lycopersicum esculentum) by using hyperspectral imaging (HSI) in the range of 1000-1400 nm. The mean spectra of the 95 matured tomato samples were extracted from the hyperspectral images, and the reference firmness and sweetness index of the same sample were measured and calibrated with their corresponding spectral data by partial least squares (PLS) regression with different preprocessing method. The results showed that the regression model developed by PLS regression based on Savitzky-Golay (S-G) second-derivative preprocessed spectra resulted in better performance for firmness, and SI of tomatoes compared to models developed by other preprocessing methods, with correlation coefficients (rpred) of 0.82, and 0.74 with standard error of prediction (SEP) of 0.86 N, and 0.63 respectively. Then, the feature wavelengths were identified using model-based variable selection method, i.e., variable important in projection (VIP), resulting from the PLS regression analyses and finally chemical images were derived by applying the respective regression coefficient on the spectral image in a pixel-wise manner. The resulting chemical images provided detailed information on firmness, and sweetness index (SI) of tomatoes. Therefore, these research demonstrated that HIS technique has a potential for rapid and non-destructive evaluation of the firmness and sweetness index of tomatoes.

• Korean Journal of Agricultural Science
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• v.45 no.4
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• pp.823-837
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• 2018

The objective of this study was to evaluate the firmness and the sweetness index (SI) of tomatoes with a hyperspectral imaging (HSI) technique within the wavelength range of 1000 - 1550 nm. The hyperspectral images of 95 tomatoes were acquired with a push-broom hyperspectral reflectance imaging system, from which the mean spectra of each tomato were extracted from the regions of interest. The reference firmness and sweetness index of the same sample was measured and calibrated with their corresponding spectral data by partial least squares (PLS) regression with different preprocessing methods. The calibration model developed by PLS regression based on the Savitzky-Golay second-derivative preprocessed spectra resulted in a better performance for both the firmness and the SI of the tomatoes compared to models developed by other preprocessing methods. The correlation coefficients ($R_{pred}$) were 0.82, and 0.74 with a standard error of prediction of 0.86 N, and 0.63, respectively. Then, the feature wavelengths were identified using a model-based variable selection method, i.e., variable importance in projection, from the PLS regression analyses. Finally, chemical images were derived by applying the respective regression coefficients on the spectral image in a pixel-wise manner. The resulting chemical images provided detailed information on the firmness and the SI of the tomatoes. The results show that the proposed HSI technique has potential for rapid and non-destructive evaluation of firmness and the sweetness index of tomatoes.

• Journal of Apiculture
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• v.33 no.4
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• pp.297-301
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• 2018

Hawthorn is widely distributed in Korea and has been used as herbal medicine for treating various cardiovascular disease, arteriosclerosis and hypertension in Korea. In order to select superior honey tree plant from Korea, the free sugar and organic acid in hawthorn fruits, including five Korean clones and four Chinese cultivars, were evaluated. We also compared these hawthorn fruits of five clones (selected from different area of Korea) with Chinese hawthorn cultivars. Glucose, galactose, fructose and sucrose were the major sugar components of hawthorn. In this study, we observed that sucrose, glucose and fructose content. The highest sucrose content of hawthorn fruit was 188.12g/100g in Daegeumseong cultivar. The sweetness index, which plays important role of taste, was also calculated from the content of sucrose, glucose and fructose. The contribution of each carbohydrate was calculated, based on the fact that fructose is 2.30 and sucrose 1.35 times sweeter than glucose. The highest sweetness of hawthorn fruit was 579.52 in Pocheon clone. Main organic acid detected in hawthorn fruit were citric acid, malic acid and shikimic acid. The highest citric acid and malic acid content in hawthorn fruit were 157.50g/100g (Pocheon 3) and 34.12g/100g (Daegeumseong), respectively. The results of this study would be helpful for using food and functional food products, due to the beneficial effects of free sugar and organic acid for human health such as antioxidants and anticarcinogenic properties.

• Korean journal of food and cookery science
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• v.19 no.6
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• pp.737-744
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• 2003

The effects of xylitol and/or erythritol as the alternative ingredients to sugar on the quality characteristics of Yuza tea were studied. The relative sweetness of xylitol and erythritol to a 10％ sucrose solution were 1.10 and 0.71 respectively and there were no change after the addition of the acid and flavoring agent. The sensory characteristics of Yuza tea with xylitol were quite similar in many attributes to Yuza tea with sugar, while Yuza tea with erythritol had many undesirable attributes. Yuza tea with a mixture of xylitol and erythritol(1:1) was less sweet and less acceptable than Yuza tea with sugar. The consumer acceptance test showed that the overall acceptability of Yuza tea made with xylitol was similar to the Yuza tea with sugar. Adding sucralose to the Yuza tea with a mixture of xylitol and erythritol improved the sweetness and overall acceptability in the consumer acceptance test. The pH value of the erythritol Yuza tea was 3.16 and showed a significantly lower value than the 3.39 of sugar and xylitol. The refractive index of the sugar Yuza tea was the highest at 21.03$^{\circ}$Bx. The vitamin C content of Yuzachung with sugar was 34.5mg/100g and the dietary fiber content was 2,80g/100g. Xylitol Yuzachung showed the highest a and b values, but when it was diluted with water to make Yuza tea, the intensity of the color was not significantly different from the Yuza tea with sugar.

• Journal of the East Asian Society of Dietary Life
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• v.26 no.1
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• pp.34-43
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• 2016

This study was performed to improve the quality index of paprika by assessment of instrumental test and sensory attributes. Red paprika (11 cultivars), orange paprika (9 cultivars), and yellow paprika (10 cultivars) were provided by GyeongNam (GN) and JeonBuk Agricultural Research and Extension Services (JB). We measured hardness and color values using a colorimeter and TPA as well as developed new terminology such as cucumber taste, grass taste, green pepper flavor and appearance (size, color size, color, and glossiness), texture (hardness, juiciness), and taste (sweetness, pungency, sourness) to describe paprika quality attributes by trained panels. a* value of red 'Nagano' cultivar provided by JB was significantly low, and only b* value of orange paprika was significantly different among the samples. In the case of yellow paprika, b* values were not significantly different, and hardness was significantly different. Overall color values were different among samples provided by GN. Oranos, orange paprika, L value, b value, and hardness were different among the samples. Bitterness was negatively correlated with sweetness and positively correlated with green pepper aroma (p<0.05). Overall acceptability was positively correlated with size, juiciness, and sweetness (p<0.01) and negatively correlated with pungent (p<0.05) and bitterness (p<0.01). In conclusion, negative attributes such as bitterness and pungentness as well as positive attributes such as size, juiciness, and sweetness must be considered as important factors for consumer preference and breeding of new cultivars.

• Korean Journal of Food Science and Technology
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• v.24 no.3
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• pp.289-293
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• 1992

This study was carried out to investigate the quality characteristics of commercial breakfast cereals. The results showed that as water absorption index (WAI) increased, water soluble index (WSI) decreased. WSI has an effect on Bowl life, so Bowl life became longer as WSI enhanced. The size, shape and texture of breakfast cereals were also affective factors of their Bowl life. The quality describing terms of breakfast cereals were surveyed and the terms were classified to brittleness, roasted nutty taste, sweetness, hardness and aftertaste, especially brittleness was the most important quality determining terms among these. Significantly, sweetness had positive correlationship with roasted nutty taste. Overall eating quality had positively correlationship with color and roasted nutty flavor, and negatively with pain in mouth, adhesiveness and additive taste.

• The Journal of the Convergence on Culture Technology
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• v.8 no.6
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• pp.921-926
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• 2022

Sugar solutions (5%, 10%, 15% and 20%) were tested by seven sensors of Astree E-Tongue for selecting a sensor for sweetness. NMS sensor was chosen as a sensor for sweetness among two sensors (PKS and NMS sensors selected in first stage) by considering precision, linearity and accuracy. Sugar, fructose, glucose and xylitol (5%, 10% and 15%) were tested by E-tongue. The principal component analysis (PCA) result by E-Tongue with seven sensors at 5% concentration level of four sweetners was not satisfactory (Discrimination index was -0.1). On the other hand, the relative NMS sensor response values were derived as 1.08 (fructose), 0.99 (glucose) and 1.00 (xylitol) comparing to sugar. Only the E-Tongue relative glucose response 0.99 was different from 0.5~0.75 of the relative sweetness range reported as the human sensory test results. Considering the excellent precision (%RSD, 1.53~3.64%) of E-Tongue using NMS single sensor for three types of sweeteners compared to sugar in the concentration range of 5% to 15%, replacing sensory test of sweetened beverages by E-Tongue might be possible for new product development and quality control.

• Horticultural Science & Technology
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• v.35 no.4
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• pp.446-455
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• 2017

We investigated the physicochemical and sensory characteristics of oriental melon (Cucumis melo L.) to provide a consumer-oriented quality index. Oriental melon fruits were harvested at 20, 25, or 30 days after fruit set (DAFS), and each group was sorted by size (small, medium, and large). Fruits harvested at 25 and 30 DAFS had higher CIE $a^*$ and $b^*$ values, higher soluble solids content (SSC), and lower CIE $L^*$, firmness, and titratable acidity (TA) values than fruits harvested at 20 DAFS. Fruits harvested at 25 and 30 DAFS scored more highly for overall acceptance. A significant correlation was found between physicochemical characteristics and overall acceptance. In the delayed-harvest sample, increased sweetness and yellowness, and decreased sensorial texture were associated with an increase in overall acceptance. In principal component analysis, F1 and F2 explained 62.16% and 17.91% of the total variance (80.07%), respectively. Regression analysis of overall acceptance and F1 gave a coefficient of determination ($r^2$) of 0.87. Our results show that consideration of the physicochemical characteristics (CIE value, SSC, pH, SSC/TA ratio, and firmness) and sensory characteristics (yellowness, placenta area condition, oriental melon odor, sweetness, oriental melon flavor, texture, and off odor) of oriental melon in this way can be used as quality indices to predict consumer acceptance.

• The Korean Journal of Food And Nutrition
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• v.28 no.1
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• pp.66-72
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• 2015

This study was conducted to investigate the effect of Perilla frutescens powder on physiological and sensory characteristics in macaron$\grave{e}$. The perilla powders were added to macaron$\grave{e}$ at a weight percentage of 0, 2.5 and 4%. Color values (L-value, redness and yellowness index), total phenolics, DPPH radical scavenging activity, textures, total sugar contents and sensory characteristics of macaron$\grave{e}$ made with varying levels of perilla powder were measured. In sensory evaluation, significant differences (p<0.05 and p<0.01) were shown in color, sweetness, nuttyflavor, texture and overall acceptability depending on the addition level of perilla powders.

• Food Quality and Culture
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• v.3 no.2
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• pp.59-63
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• 2009

As one of study efforts to develop a food product that can satisfy the taste of modern people and increase the usage of the popular local product of walnut in the region of Chunan, the current study developed a no sugar added functional walnut-sulgi. The walnut-sulgi was manufactured by adding walnut powder into typical sulgi rice cake. While manufacturing the walnut-sulgi rice cake, the health beneficial sugar alcohol ingredient of sorbitol was added instead of commonly used sugar to specialize the walnut-sulgi as a functional rice cake. As the result of such effort, a soft and moist walnut-sulgi was produced. The color of the newly developed walnut-sulgi is white and has a pleasing taste, and its consumer acceptability was higher than the sugar added walnut-sulgi by showing much soft sweetness and textural properties. Considering the facts that sorbitol has a lower glycemic index (GI) than sugar and the content of unsaturated fatty acids that are insufficient in rice cake could be increased, the newly developed sorbitol added walnut-sulgi is thought to be an appropriate functional rice cake that can attractively appeal to obesity and diabetes concerning modern people.