• Journal of the East Asian Society of Dietary Life
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• v.18 no.6
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• pp.965-973
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• 2008

In this study, we compared the quality and sensory characteristics of 4 types of fresh tomatoes and 2 types of canned tomatoes, and then determined the most preferred quality characteristics and tomato type for the production of tomato sauce. The sample tomatoes were prepared by cutting after either peeling or heating for 5 min. Soluble solids were in the following order: Italian canned >American canned, Cherry> Vita king > Aranka > general tomatoes. The primary free sugars were fructose and glucose, and we determined that fructose and glucose were the most prevalent sugars in the cherry and American canned tomatoes. The total sugars, which were the sum of the fructose and glucose contents, were consistent with the soluble solid contents. pH was measured in the following order: general> Italian canned> Cherry, Vitaking> Aranka> American canned tomatoes. The most abundant amino acid was glutamic acid, and its content in the unheated tomatoes occurred in the following order: American canned> Italian canned> Vita king> Cherry> general tomatoes; however, after heating, the Vita king tomato was followed by the American canned tomato. The lightness (L value) of the fresh tomatoes tended to be higher than that of the canned tomatoes, and it decreased after heating. The redness (a value) of the unheated tomatoes was in the following order: Italian canned> American canned> Vitaking tomatoes; after heating, the Vitaking evidenced the highest values, followed by the canned tomatoes. The result of our QDA profile of sensory characteristics according to redness, aroma, sweet taste, sour taste, palatability, and viscosity was in the following order: Italian canned > American canned > Vitaking tomatoes, which evidenced the most balanced hexagonal shape. In the preference test, 2 types of canned tomatoes and Vitaking tomatoes were the most preferred among the fresh tomatoes. From the correlation coefficients among the sensory characteristics, canned tomatoes were the most preferred for the production of tomato sauce due to its high redness, flavor, palatability, and viscosity values. Vitaking tomatoes were the most appropriate among the fresh tomatoes.

• Korean Journal of Food Science and Technology
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• v.16 no.1
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• pp.59-65
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• 1984

Effect of ripening methods and harvesting time on vitamin content of 5 tomato varieties was investigated in 1978 and 1979. Ascorbic acid content in the breaker ripened tomatoes was significantly higher than that in the vine ripened tomatoes, and the result was consistent for two consecutive years. Ascorbic acid content in the vine ripened tomatoes markedly increased as the season progressed, early harvested tomatoes containing significantly less ascorbic acid. Carotene content was not significantly affected by the ripening method. Higher carotene content, however, was observed for tomatoes harvested in the late season. This result could indicate the effect of temperature for carotenogenesis around the harvest time. Thiamin and riboflavin contents in the vine ripened tomatoes were significantly higher than those in the breaker ripened tomatoes in the 1978 season, but these differences were not observed in the 1979 season. Thiamin and riboflavin contents in the vine ripened tomatoes decreased considerably as the season progressed. Thiamin and riboflavin contents in tomatoes harvested in the early season were significantly higher than those in the mid and late seasons.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.5
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• pp.791-797
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• 2009

We investigated the quality and sensory characteristics of model tomato sauces which was made from fresh Vitaking tomatoes and American canned tomatoes in the mixture ratios of 0:100% ($S_1$), 25:75% ($S_2$), 50:50% ($S_3$), 75:25% ($S_4$) and 100:0% ($S_5$). Soluble solids, reducing sugars, vitamin C and organic acids increased as the contents of fresh tomatoes increased. pH and contents of $\beta$-carotene and lycopene decreased as the contents of fresh tomatoes increased. Lightness(L value) and yellowness (b value) increased as the contents of fresh tomatoes increased whereas redness (a value) didn't show any significant differences among samples. In the preference test, $S_3$ was the most preferred in red color, taste and overall preference. In the descriptive test, $S_1$ ranked the highest in redness, viscosity, palatability and flavor except for sweet and sour taste. $S_5$ was the lowest in redness, viscosity and palatability, being the highest in sour taste. From this result, we found that the mixture ratio of half fresh tomatoes and canned tomatoes was the best condition to make tomato sauce with preferred red color.

• Agricultural and Biosystems Engineering
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• v.1 no.2
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• pp.81-87
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• 2000

Quality characteristics of tomatoes irradiated with light (red light of far-red light followed two days later with a red light treatment), treated with ethylene, and stored in darkness were evaluated by subjective sensory and objective physical and chemical evaluations. Overall and individual liking evaluations and sensory evaluations were made by an untrained panel of eighteen people. A rankin gof treatments for consumer (panelist) acceptability was also conducted by the panel. Physical and chemical evaluations included surface color measurement (L*, a*, and b*), mechanical puncturing (firmness), soluble solids content (SSC), titratable acidity(TA), and tomato juice pH. Sensory data showed that outside color, inside color, and flavor of tomatoes treated with red light (R) and far-red light/red light (FR/R) were scored significantly higher than those of tomatoes treated with ethylene and those kept in darkness. The L* values for tomatoes treated with R and FR/R were lower (more darkening) than those for tomatoes treated with ethylene and those stored in darkness. Tomatoes treated with FR/R had the highest A* values, followed by those irradiated with R, treated with ethylene, and kept in darkness, respectively. Sensory values for firmness were similar for tomatoes treated with R, FR/R, and ethylene. Treatments had no significantly different effects on sweetness and acidity. There were no significantly different effects between treatments for pH, SSC, TA, and SSC/TA. From observations made during the study, it was suggested that R irradiation stimulated red color development in tomatoes after it had been delayed by FR irradiation. Consumer acceptability for tomatoes with either R or FR/R treatment was significantly higher than that for tomatoes treated with ethylene or stored in darkness. panelists' overall liking scores correlated well with all sensory variables except acidity, and also correlated highly with inside color, flavor, and sweetness (P<0.001). Overall liking versus flavor had the most pronounced relationship (r=0.78, P<0.001).

• Korean Journal of Organic Agriculture
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• v.31 no.1
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• pp.1-27
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• 2023

This study investigated Thai consumers' perception and willingness to pay for Korean paprika and tomatoes to establish effective export strategies, To this end, an online survey was conducted on 300 consumers living in Bangkok, Thailand, and the factors affecting the purchase intent and willingness to pay price premium for Korean paprika and tomatoes were analyzed. The results are as follows. First, Thai consumers usually buy fruit and vegetables offline, such as supermarkets and large discount stores, but not a few respondents obtained purchase information online. Second, the price competitiveness of Korean paprika and tomatoes is low to Thai products, and the quality, safety, freshness, and cost-effectiveness are similar or low to other exporting countries. Therefore it is important to improve non-price competitiveness using positive perceptions of Korean products and Korean Wave. Third, the most important reason why Thai consumers not buying Korean paprika and tomatoes is the lack of stores and high prices. Fourth, as a result of analyzing the factors affecting the purchase intent for Korean paprika and tomatoes, the strategy of selling paprika and tomatoes through supermarkets to consumers with high income is effective. Fifth, considering the factors of willingness to pay premium prices for Korean paprika and tomatoes, a high pricing strategy targeted consumers with high income and many family members is appropriate.

• Journal of Biosystems Engineering
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• v.18 no.4
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• pp.382-389
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• 1993

In this research, the surface color of 'Fuji' apples and tomatoes were measured by using Sharp PD 151 semiconductor color sensors. The measurements were compared with color-difference-meter readings and with visual sensory test scores. A negative exponential function was developed which describe the relationship between the dominant wavelength of the surface color of 'Fuji' apples and the ratio of the photoelectric currents of the color sensor. Also a linear relationship was found for the surface color of tomatoes and the color sensor output. There were good correlations between the visual test scores and the color sensor output for both 'Fuji' apples and tomatoes.

• Culinary science and hospitality research
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• v.17 no.5
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• pp.193-205
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• 2011

This study aimed to enhance the quality and sensory acceptability of dak-galbi sauce made from general tomatoes, plum tomatoes and canned tomatoes and find the most preferred quality characteristics and tomato type for the production of dak-galbi sauce. Dak-galbi sauce was blended with different concentrations of tomatoes (0%, 10%, 20%, 30%, 40%). As the amount of a tomato addition increased, the moisture contents, L-values, a-values and B-values significantly(p<0.001) increased while salinity, sugar contents and viscosity decreased. The attribute difference test showed that significant differences in such properties as color intensity, pungent flavor, pungent taste, mouthfeel were observed with more tomatoes added. Based on the results of this study, the optimal tomato content for maximizing the overall quality of dak-galbi sauce was 10~20% of general tomatoes or 20% of plum and canned tomatoes. More various kinds of dak-galbi sauce are expected to be developed through this study.

• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1283-1287
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• 1999

This study was carried out to develop new processed food from cherry tomatoes. The dried cherry tomatoes were prepared by using a sequence of osmotic dehydration, air drying, vacuum drying and freeze drying. The moisture contents of dried cherry tomato products by nontreatment and osmosis treatment were about 11~13% and 7.5~ 10%, respectively. The vitamin C contents of the dried product after osmotic dehydration were higher than those of the dried products by nontreatment. The vitamin C content of the freezing dried product was the highest of the others. The vacuum dried product by nontreatment was retained color of fresh fruit in the change of color. The ΔE value of the air dried product was lower than those of the others. As a result to microscopic analysis, fresh cherry tomato was observed regular tissue, while cherry tomato treated by osmosis was observed a cell collapse following the loss of water. The dried product had cell shrinkage and dense tissue. And the cell wall of dried products after osmotic dehydration were much more damage than those of nontreatment dried product. The palatability of the air dried product was the best of three drying methods. The dried cherry tomatoes treated by osmosis were superior to the dried cherry tomatoes by nontreatment.

• Journal of Biosystems Engineering
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• v.38 no.3
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• pp.199-207
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• 2013

Purpose: Tomatoes, an important agricultural product in fresh-cut markets, are sometimes a source of foodborne illness, mainly Salmonella spp. Growth cracks on tomatoes can be a pathway for bacteria, so its detection prior to consumption is important for public health. In this study, multispectral Visible/Near-Infrared (NIR) reflectance imaging techniques were used to determine optimal wavebands for the classification of defect tomatoes. Methods: Hyperspectral reflectance images were collected from samples of naturally cracked tomatoes. To classify the resulting images, the selected wavelength bands were subjected to two-band permutations, and a supervised classification method was used. Results: The results showed that two optimal wavelengths, 713.8 nm and 718.6 nm, could be used to identify cracked spots on tomato surfaces with a correct classification rate of 91.1%. The result indicates that multispectral reflectance imaging with optimized wavebands from hyperspectral images is an effective technique for the classification of defective tomatoes. Conclusions: Although it can be susceptible to specular interference, the multispectral reflectance imaging is an appropriate method for commercial applications because it is faster and much less expensive than Near-Infrared or fluorescence imaging techniques.

• Culinary science and hospitality research
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• v.23 no.7
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• pp.42-49
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• 2017

This study was conducted to determine the nutritional value of domestic cherry tomato varieties (Summerking, Qutiquti, and Minichal). The levels of amino acids, amino acid derivatives, and ${\gamma}-aminobutyric-acid$ (GABA) were analyzed using ion chromatography. In domestic cherry tomatoes, eighteen free amino acids were found including L-glutamic acid (L-Glu), L-glutamine (L-Gln), and L-aspartic acid (L-Asp). L-Glu was the most abundant amino acid, ranging from 1,533.17 mg/100 g to 1,920.65 mg/100 g (dry weight). The next abundant amino acids were L-Gln, ranging from 784.68 mg/100 g to 1,164.36 mg/100 g and L-Asp, ranging from 320.73 mg/100 g to 387.22 mg/100 g. Domestic cherry tomatoes contained eight essential amino acids except tryptophan and the total essential amino acid content was 297.30~432.43 mg/100 g (dry weight), which was 8.92~10.61% of total free amino acid. Several amino acid derivatives were found: L-carnitine (L-Car), hydroxylysine (Hyl), o-phosphoethanolamine (o-Pea), phosphoserine (p-Ser), ${\beta}-alanine$ (${\beta}-Ala$), N-methyl-histidine (Me-His), ethanolamine ($EtNH_2$), and L-citrulline (L-Cit). L-Car, transporting long-chain fatty acid into mitocondrial matrix, was the most abundant amino acid derivative in all domestic cherry tomatoes. A high level of GABA (313.18~638.57 mg/100 g), known as a neurotransmitter, was also found in all three domestic cherry tomatoes. These results revealed that domestic cherry tomatoes have a good balance of nutrient and bioactive compounds. Therefore, cherry tomatoes can be used as a functional food material.