• Journal of the Korean Society of Food Science and Nutrition
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• v.29 no.2
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• pp.181-187
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• 2000

The contents of organic acid in Korean apple juice were analyzed by HPLC using YMC-peak ODS-AQ column and enzymatic assay. Model apple juices were prepared at the laboratory and commercial apple juices were purchased from the market. Individual organic acid contents were as follows: DL-malic acid 62~402mg%, L-malic acid 48~360mg%, citric acid 1.81~15.74mg%, fumaric acid nd~0.50mg%. Together, these tests gave useful information about the quality and authenticity of a particular apple juice smaple. The presence of D-malic acid was a clear indication of adulteration because this isomer did not occur naturally. Fumaric acid and citric acid levels above trace amounts were also inconsistent with pure apple juice.

• Korean Journal of Environmental Agriculture
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• v.42 no.3
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• pp.239-252
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• 2023

Most apple trees in South Korea are grafted on M.9 and M.26 rootstocks; however, these rootstocks are susceptible to fire blight. Although M.7 rootstocks are moderately resistant to fire blight, they tend to exhibit excessive vigor, which is unsuitable for high-density planting, unless weak cultivars are used. This study investigated the vegetative growth, yield, and fruit quality of apple trees grafted onto M.7, M.9, or M.26 rootstocks to assess the feasibility of establishing high-density apple orchards domestically using the M.7 rootstock a period of seven years (1-7 years after planting). Rootstocks were tested using three cultivars with contrasting induced vigor and harvesting times: vigorous and late-maturing 'Fuji,' moderate vigor and middle-maturing 'Hongro,' and low vigor and early-maturing 'Sansa.' The planting density was maintained constant, with 190 trees per 10 a. Primary thinning (leaving only the king fruit on clusters) was performed, whereas secondary thinning (controlling crop load) was not. Vegetative growth, accumulated yield per 10 a, and yield efficiency varied depending on cultivars and rootstocks; however, the cultivars had a more notable effect on fruit quality than the rootstocks. Biennial bearing often occurred in the M.26 rootstock. 'Fuji'/M.7 was overly vigorous for high-density planting. The fruit quality and accumulated yield per 10 a of M.7 were similar to those of M.9 with the 'Hongro' and 'Sansa' cultivars. In particular, 'Hongro'/M.7 did not show tree vigor reduction due to heavy crop load, and the degree of biennial bearing in 'Sansa'/M.7 was not particularly high. These results indicated that high-density apple planting using the M.7 rootstock was achievable using the 'Hongro' and 'Sansa' cultivars.

• Preventive Nutrition and Food Science
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• v.8 no.3
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• pp.225-229
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• 2003

Clarified apple, carrot and orange juices were prepared using ultrafiltration and their single and blend juices were further concentrated using ultrafiltration, freeze-drying, and rotary evaporation. Effect of concentration methods on the quality of concentrated single juices and juice blends was investigated. Turbidity values of samples concentrated by evaporation were significantly higher than those prepared by ultrafiltration and vacuum freezing regardless of juice source (i.e., apple, orange or carrot) or blending (p<0.05). The highest soluble solids contents were obtained for the samples concentrated by evaporation process. Concentrated apple juice contained significantly higher amount of vitamin C and soluble solids than concentrated orange and carrot juices regardless of concentration methods (p<0.05). For blended samples, no direct relationships between blend ratio and total amount of vitamin C were found; however, samples contained more apple juice showed the highest value of soluble solids regardless of concentration methods.

• Near Infrared Analysis
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• v.1 no.1
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• pp.27-30
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• 2000

In this study, we investigated the feasibility of non-destructive determination of internal quality factors of Fuji apple fruit using near infrared(NIR) reflectance spectroscopy and developed the calibration models. As the reference methods, refractometer, titration and texture analyzer for sugar content, acidity and firmness were used, respectively. Samples were scanned from 1100∼2500nm with InfraAlyzer 500C spectrometer and SESAME software was used for data analysis. A multiple linear regression(MLR) analysis was performed to develop the calibrations. The correlation coefficient(R) and standard error of prediction(SEP) were as follows; 0.91, 0.41$^{\circ}$Brix for sugar content, 0.90, 0.04% for acidity and 0.84, 0.094 kg for firmness, respectively. This study shows that NIR spectroscopy can be used to evaluate the sugar content acidity and firmness of apple fruit with acceptable accuracy.

• Korean Journal of Organic Agriculture
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• v.9 no.4
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• pp.123-134
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• 2001

The quality including in situ degradability in the rumen of Holstein of the black locust silage added with apple pomace was investigated in this study. The amount of apple pomace added in different treatments were 0, 20, 40 and 60% respectively. With higher amount of addition of apple pomace in black locust, crude protein content in the silage decreased. Crude protein contents in the apple pomace added silage were in the range between 11.7 and 13.7% and those were significantly lower than 16.3% of 100% black locust silage. The contents of ADF, NDF and crude ash were in the same trend as with crude protein, which were shown more clearly in the 40∼60% addition of apple pomace. Moisture content of 100% black locust silage was 56.7% however it significantly increased according to higher levels of addition of apple pomace(67.1∼73.8%). pH, lactic acid and total organic acid contents in 20∼60% addition of apple Pomace were 3.7∼4.3, 1.3∼2.2%, and 2.1∼6.0% respectively, however in 100% black locust silage those were significantly lower except pH as 5.4, 0.6% and 1.0% respectively. In situ disappearance rates of dry matter and NDF in the rumen were significantly higher at the stapes of incubation after 12h and 24h respectively in 20∼40% addition of apple pomace than in 100% black locust silage. No statistical differences were observed with quickly degradable fraction (a) in the disappearance rates of dry matter and NDF. In dry matter, however slowly degradable fractions (b) of 100% black locust and 60% addition of apple pomace were significantly higher as 99.7 and 99.8% respectively than 37.7∼50.5% of 20∼40% addition of apple pomace. On the contrary, fractional rate of disappearance (c) and effective degradability(ED) were significantly higher in 20∼40% addition of apple pomace as 0.0115∼0.0149 and 30.4∼31.9% respectively than the respective values of 0.0027 and 24.9% of 100% black locust. In NDF, b was significantly higher in apple pomace added silage(38.5∼99.8%) than in 100% black locust silage(14.9%). However, C was significantly lower in apple pomace added silage than in 100% black locust silage.

• Korean Journal of Agricultural Science
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• v.39 no.1
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• pp.151-159
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• 2012

This paper analyzes the consumers' preference for packaged apple and derives the measures to vitalize the distribution of packaged apple. To do this, survey was conducted for consumers in large cities, Seoul, Busan, and Daegu to observe their purchasing behavior and satisfaction both for packaged and unpackaged apple. Survey was focused to how they are satisfied with several attributes of package such as size, appearance, content, material, and label. On the basis of the survey results, the values of the package attributes were estimated. Survey results show that consumers tend to buy unpackaged apple rather than packaged apple. About 34 percent out of 313 respondents have ever purchased apple packed with paper box while only 10.5 percent have an experience to buy packaged apple with transparent box. Most respondents answered they preferred the package of five to six apples and 1.3 kilograms most. They preferred mid or large size apple. Estimation of the values of the package attributes using the conjoint analysis shows that consumers are giving the highest value to the price of packing material. It means that consumers are reluctant to the extra payment resulted from packing the apple. Therefore, the efforts to reduce the cost of packing apple should be made steadily. In order to vitalize the distribution of small packaged apple, the package should contain high quality apple with high sugar content, proper size, good appearance, and so on. And it needs to be promoted to the consumers that small packaged apple are not inferior to apple packed with paper box.

• Culinary science and hospitality research
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• v.22 no.8
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• pp.89-98
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• 2016

The objective of this study was to exploit the use of this nutrient-rich byproduct in cookies by replacing wheat flour at 10~30% levels. The specific gravity and pH of cookies decreased slightly with increasing apple pomace concentration, but the specific gravity of cookies showed no significant difference in the additive group. The sugar contents of cookies was significantly increased to $2.07^{\circ}Brix$ at 30%. Moisture content, spread factor, loss rate, and leaving rate of cookies increased with increasing apple pomace concentration. Lightness, redness, and yellowness of cookies decreased from 70.46 to 56.25, and 5.60 to 3.01, and 37.52 to 27.92, respectively, with increasing apple pomace concentration. In the sensory evaluation, sensory scores for color, flavor, texture, appearance, and overall preference were highest in the 10% and 20% apple pomace cookies in the additive group. Thus, our results suggested that the optimum amount of apple pomace that can be added to cookies was 20%.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.2
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• pp.144-150
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• 2008

In this study, the PVDF (polyvinylidene fluoride) piero-film sensor was applied to measure the internal quality of apple. The developed sensor detected the response signal through apple after mechanical impact on the surface of apple. The acoustical parameters at time domain such as rise time (RT), ring down count (RC), energy (EN), event duration (ED) and peak amplitude (PA) and acoustical parameter at frequency domain such as spectral density (SE) were analyzed. The size of waveform decreased as storage time of apple increased. The frequency at maximum magnitude was shifted to lower frequency band according to the storage time. The acoustical parameters showed strong relationship with storage time. The multiple linear regression equation was developed to estimate storage time of apple using the acoustical parameters at time domain and its coefficient of determination was 0.97. The internal quality of apple according to storage time is predictable using developed PVDF sensor and acoustical parameters defined in this study.

• Korean Journal of Organic Agriculture
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• v.11 no.2
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• pp.91-101
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• 2003

This study was tried to examine the efficacy of apples that had grown with agro-chemical alternatives in an apple orchard. The chlorophyll content of apple leaves was a little higher in the plot of Charcoal powder, Chitosan, and Peat moss treatment among the other agro-chemical alternatives. On the contrary, the sugar content of apple fruits was higher in the plot of Amino acids, and Green ion calcium treatment, but there was quite a difference among them. Vitamin C content of apple fruits was high at the cell division period. It became lower at the hypertrophic period and then got higher again at the harvest. Vitamin C content was the highest in the chemical fertilizer plot as well. In an apple orchard where agro-chemical alternatives were used only, the commercial grade of ripened apples had declined by 25％, compared to those in customary cultivation. The commercial grade of ripened apples with agricultural chemicals using fertilizers and pesticides was over 90％ with over 250g of its weight in the plot of Charcoal powder, Amino acids, and Vitamin C treatment. Therefore. we guessed the environment-friendly method of cultivation in an apple orchard shall be established by reducing the usage of agricultural chemicals gradually and increasing the agro-chemical alternatives at the same time.

• Culinary science and hospitality research
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• v.20 no.2
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• pp.79-88
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• 2014

This study investigated the quality characteristics of apple jam added with ginger. The apple jam was prepared with apples, sugar, lemon juice and various amounts (0, 2, 4, 6, 8%) of ginger. Increasing the amount of ginger decreased moisture contents and sugar content of the jam, whereas the pH gradually increased. In addition, with increased amount of ginger, the lightness(L) and yellowness(b) significantly decreased, while redness(a) gradually decreased. There wasn't any significant difference in the samples with up to 4% ginger(p<0.05). In the texture profile analysis, hardness and adhesiveness increased significantly with increased amount of ginger. When more amount of ginger was added, cohesiveness increased with no significant difference based on the amount of ginger. With increased amount of ginger, springiness and chewiness gradually increased. The results of the sensory evaluation show that the apple jam added with 4% ginger got the highest overall-acceptability scores. In conclusion, it is possible to enhance the quality and acceptability of apple jam by adding 4% ginger.