• Korean journal of food and cookery science
• /
• v.21 no.3 s.87
• /
• pp.360-370
• /
• 2005

The aim of this study was to fud the optimum addition mont of astringency persimmon paste to rice flour in the preparation of Gamsulgiduck (persimmon rice cake). The moisture content of Gamsulgiduck with added astringency persimmon paste was $42\~45\%$. With increasing addition of astringency persimmon paste, the L-value was decreased. The a- and b-values were the highest at the $15\%\;and\;10\%$ levels, respectively. In the mechanical evaluation of Gamsulgiduck the hardness was the lowest at the $20\%$ astringency persimmon paste-sulgiduck during storage. The adhesiveness and cohesiveness did not differ significantly with the addition of astringency persimmon paste for storage period. The springiness was the highest at the $0\%$ level except for 2days of storage. The gumminess was the lowest at the $20\%$ level and the brittleness was the highest at the $0\%$ level during storage. In the sensory evaluation of Gamsulgiduck the acceptance of the softness and chewiness characteristics was the best at the 15% level. Gamsulgiduck with the addition of $15\%$ of astringency persimmon paste to rice flour was found to be the best recipe in terms of the sensory qualities of softness, chewiness and overall acceptability.

• Food Science and Preservation
• /
• v.6 no.1
• /
• pp.66-70
• /
• 1999

The mechanism of natural removal of astringency and seasonal changes of tannin substance in sweet persimmon(Fuyu) and astrigent persimmon(Chungdo Bansi)were investigated. Tannin productivity of astringent persimmon fruit was higher than that of sweet perimmon fruit during growth. In the reactivity of tannin to acetaldehyde, it was observed that tannin from sweet persimmon have a milder chemical properties than that from astrigent persimmon. The threshold value of astringency on sweet persimmon tannin was higher than that of astrigent persimmon tannin. Tannin substances from sweet persimmon distributed mainly in lower molecular weight range at harvest stage, but those from astrigent persimmon distributed mainly in higher molecular weight range. Therefore, the natural removal of astringency was related to difference of tannin productivity, threshold value of astringency, reactivity and qualitative difference of tanni.

• Korean journal of food and cookery science
• /
• v.30 no.3
• /
• pp.351-359
• /
• 2014

The application of persimmon for making new products was investigated by analyzing the degree of astringency removal, softness of fruit, and sensory properties of Daebong persimmons (Diospyros kaki L) treated with three different astringency removal methods of steeping in water, steeping in 1% salt solution, and vacuum packing at $40^{\circ}C$. The weight of persimmon fruit increased with increasing steeping time, but decreased with increasing vacuum packing time. The fruit steeped in $40^{\circ}C$ salt solution (1%, w/w) was not detected with soluble tannin and not developed color with ferric chloride after steeping for 9 h. A total of 12 h of steeping time was required for removing soluble tannin using other methods. The lightness (L) in color and hardness in texture decreased when storage time increased, regardless of astringency removal methods. In overall, the preference was shown with the highest score in persimmon steeped in salt solution for 9 h and 12 h that were vacuum packed at $40^{\circ}C$. In conclusion, the astringency removal condition of Daebong persimmon was good after being steeped on 1% salt solution for 9 h at $40^{\circ}C$.

• Food Science and Preservation
• /
• v.6 no.4
• /
• pp.392-397
• /
• 1999

The quality changes during the removal of astringecy by CO$_2$gas at 2$^{\circ}C$ and 20$^{\circ}C$ of three varieties of persimmons named 'Tonewase', 'Chungdobanshi' and 'Sagokshi' were examined. Astringency index and tannin content showed rapid decrease at 20$^{\circ}C$ and gradual decrease at 2$^{\circ}C$. All was edible 2days from the removal of astringency at 20$^{\circ}C$, while 'Tonewase' and 'Sagokshi' were edible on 6days and 'Chungdobanshi' on 10days after treatment at 2$^{\circ}C$. Soluble solid contents was decreased a little(1∼3%) during the removal of astringency. Hardness was decreased slowly but, kept over 1.0kg/$\phi$5mm till edible period in all varieties at 2$^{\circ}C$ and 20$^{\circ}C$. The hardness of 'Chungdobanshi' was kept well after the removal of astringency at 2$^{\circ}C$. No noticeable color changes in all varieties during treatment. Injury fruits were noticeable in only 'Tonewase' after the removal of astringency treatment at 2$^{\circ}C$.

• Applied Biological Chemistry
• /
• v.20 no.1
• /
• pp.105-108
• /
• 1977

The changes of the contents of acetaldheyde and alcohol in Chungdo Bansi was determined during the removal of astringency by treatment of $CO_2$. On the other hand, the difference of acetaldehyde and alcohol contents were determined to comparedits contents in the part of Chungdo Bansi and Buju, respectively. It showed that the variation of acetaldehyde and alchohol contents was higher 10 times non-astringent persimmon than astringent one, and acetaldehyde and alcohol contents in the core of non-astringent persimmon and sweep one were the higher than the other parts. It was assumed that acetaldehyde and ethanol contents had intimately relation to removal of astringency.

• Applied Biological Chemistry
• /
• v.19 no.2
• /
• pp.99-103
• /
• 1976

The experiment was tested with fruits of eight varieties which were produced in Kyung Pook and Kyung Nam District and was carried out to investigate the changes of sobuble tannin content, hardness and sugar content during the removal of astringency, and, further more, the changes of quality after the removal of astringency. The results were as follows: 1. Soluble tannin content of Sagoksi was most in eight varieties and than was Euisung-Bansi and Chungdo-Bansi in that order. The time required of the removal of astringency tools 2.5 days in Dansungsi, 4.5days in Sagoksi. 2. Hardness was the firmest in Sagoksi and Chungdo-Bansi and it was gradually decreased as the harvest time of fruits was delayed. 3. In content of sugar, Gojongsi was most amount and Sagoksi was least amount in all varieties. Changes of sugar content showed a gradual decrease during the removal of astringency. 4. Quality of fruit after the removal of astringency was of a very superior quality in Chungdo-Bansi, Sagoksi and Euisung-Bansi.

• Applied Biological Chemistry
• /
• v.19 no.2
• /
• pp.93-98
• /
• 1976

The experiment was made to investigate concentrations of $CO_2\;and\;O_2$ in the removal of astringency of persimmon fruits and to study the changes of total, reducing sugar and hardness during the removal of astringency. 1. During the removal of astringency of persimmon fruits, channel of tannin content showed the rapid decrease in high concentration of $CO_2$ and the gradual decrease in low concentration of $CO_2$. 2. Concentration of oxygen did not show effect on the removal of astringency at high concentration of $CO_2$ but at low concentration of $CO_2$ in Chungdo-Bansi. 3. Optimal concentration of the removal of astringency was $60{\sim}70%,\;CO_2$ and $6{\sim}8%\;O_2$ in Chungdo-Bansi and Sagoksi 4. In changes of sugar content total sugar was decreased and reducing sugar was increased.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.27 no.4
• /
• pp.648-652
• /
• 1998

Astringency in persimmons was removed by immersing in 0.5% acetic acid or various concentrations(0.1%, 0.5%, and 1.0%) of chitosan solutions for 4 days at 18$^{\circ}C$. During 5-days immersion, soluble tannin contents in persimmons decreased more rapidly while pH, 。Brix, and hardness decreased more slowly with increasing chitosan concentration. No noticeable color changes and decay were observed during this period. Sensory analyses 4 days after immersion indicated that persimmons immersed in 1.0% chitosan solution showed the best results for firmness and overall acceptability.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.4 no.1
• /
• pp.25-29
• /
• 1975

Took an experiment of the jam manufacture with the raw material―the persimmons mellowed naturally and the persimmons which were got rid of astringency artificially―with many kinds of Korean persimmons. The results as follows : 1. Table 1. shows the analysis Table of the nutritional composition in the raw persimmon and Table 2. shows the gelation factor content in the persimmon. 2. Table 3. shows the mixture ratio of the manufacturing raw material of persimmon jam and shows the properties of the jam. 3. The color of the jam manufactured with made from the natural mellowed persimmons was persimmon color containing black spot or orange. But the jam manufactured with the persimmons which were got rid of astringency by ethanol changed from persimmon color to light purple during the storage. 4. The jam manufactured with the natural mellowed persimmons did not taste astringent but the jam manufactured with the persimmons which were got rid of astringency artificially tasted astringent.

• Journal of the Korean Society of Food Culture
• /
• v.34 no.5
• /
• pp.629-636
• /
• 2019

This study examined the quality characteristics of jelly prepared with green grape juice (GJ). The pH, $^{\circ}Brix$ value, color, texture, and sensory evaluation of the jelly were measured. The pH of the jelly significantly decreased with increasing amount of GJ over the range of 3.25-5.27. The $^{\circ}Brix$ value of the jelly showed a significantly higher result as the amount of GJ increased (p<0.001). Lightness (L) and redness (a) decreased with increasing amount of GJ, and yellowness (b) increased. In the texture measurement, the GJ-100 sample group with a high substitute rate of GJ showed high hardness, gumminess, and chewiness (p<0.001). The results of principal component analysis (PCA) showed that the sample groups with high GJ content were classified as having relatively strong yellowness, sweet aroma, metallic aroma, grassy aroma, sweetness, sourness, green grape skin taste, and astringency. In the acceptance test, the GJ-50 sample group was evaluated to be high in flavor (p<0.001) and overall acceptance (p<0.01). However, sample groups consisting of 50% or more GJ were evaluated to be significantly strong in terms of astringency. Therefore, further study needs to be conducted about improving astringency in the future.