• Journal of the East Asian Society of Dietary Life
• /
• v.14 no.1
• /
• pp.70-73
• /
• 2004

The browning rate of potato juice alone and potato juice with added carrot juice or water(1:1 by volume) were studied. As the amount of carrot juice added was increased, the browning rate proportionally decreased: from 1.86 of potato juice alone to 0.36 for the potato juice and carrot juice mixture(l:1). This inhibitory effect of carrot juice on browning led us to assume that $\beta$-carotene, the major constituent of carrot carotenoids, may be involved in impeding the browning reaction of potato juice. Therefore, model system of enzymatic browning, consisting of chi orogenic acid/tyrosine and $\beta$-carotene/carrot carotenoids, were studied. The results shows the browning rates of chlorogenic acid alone and chlorogenic acid with added $\beta$-carotene. The initial browning rate of chlorogenic acid was faster($\delta$L= 1.1/min.)than that of chlorogenic acid with added $\beta$-carotene($\delta$L=0.6/min.).

• Journal of Plant Biotechnology
• /
• v.40 no.4
• /
• pp.224-230
• /
• 2013

Lily is an important cut-flower in Korea and world as well due to it's a variety of flower colors and various sizes of flowers. To develop elite lily cultivars, conventional breeding techniques have been used so far. However, an introduction of tissue culture system in mass propagation of bulbs and regeneration of shoots with a high efficiency is prerequisite at this moment. Especially, growth of bulbs and shoots as well as reduction of browning is critical factor to proliferate bulbs with shoots of superior lines or cultivar in lily. For this purpose, we tried to test whether ascorbic acid, citric acid and silver nitrate in medium to facilitate growth of bulbs and shoots as well as reduction of browning of bulb scales in lily. As a result, ascorbic acid and silver nitrate showed no significant differences compared to control plants in the growth of bulbs and shoots. When bulb scales were treated with $150mg{\cdot}l^{-1}$ of citric acid, formations of shoots and bulbs showed best result. While, bulb scale treated with $100mg{\cdot}l^{-1}$ of citric acid showed the growth of shoot and root as well as increasing of fresh weight compared to other treatments. Regarding the reduction of browning, $150mg{\cdot}l^{-1}$ of ascorbic acid showed the best result with the less than 2%. Although more experiments with several commercial varieties are needed in the future to establish mass propagation of bulbs of lily, results obtained in this study are supposed to provide the basic knowledge and contribution in tissue culture system of lily.

• Korean journal of food and cookery science
• /
• v.10 no.1
• /
• pp.24-28
• /
• 1994

The effects of synthetic and carrot carotene on the browning of polyphenolics extracted from potato for eliminating the effects of other components in potato which inhibit the browning of potato juice and the potato polyphenol oxidase (PPO) activity were investigated. Total phenolics content in potato sample was 1.854mg/g D.W. and PPO activity was 100 unit. Delta 'L'value of polyphenolics extracted from potato decreased makedly, but that of potato with carrot decreased little by little. Potato with P-carotene showed a little decrease after 50 min. At the same time, polyphenolics extracted from potato were mixed with carotene extracted from carrot or with syntetic $\beta$-carotene. As the results, the delta 'L'value of the former increased but decreased similarly to the latter after 1 hour. The effects of enzyme and substrate concentration on the browning of PPO extracted from potato were investigated. Optimum enzyme concentration was 10% and optimum substrate concentration was 13.3% $\beta$-carotene concentration did not appear to influence significantly on PPO activity.

• Journal of Ginseng Research
• /
• v.25 no.1
• /
• pp.37-40
• /
• 2001

Two kinds of ginseng extracts were prepared and their brown color and radical scavenging activity were evaluated. The extract prepared by decoction after steaming exhibited deeper brown color and stronger radical scavenging activity than the extract prepared by decoction only. The difference in color and radical scavenging activity was greater in white ginseng than in fresh ginseng. Steaming white ginseng for 3 h was equivalent to 45 h of decoction in its brown color and radical scavenging activity. Consequently, we believe steaming process is better method than decoction to increase the biological activity of ginseng.

• Applied Biological Chemistry
• /
• v.25 no.4
• /
• pp.206-210
• /
• 1982

Effects of pH, organic acides and UV irradiation on the browning of ginseng were investigated. Browning of ginseng tended to increase slightly in the alkaline pH range, whereas no discernible pH effect was observed in the pH ranges of 3.0-5.0 and 10.0-12.5. The treatment of fresh ginseng with organic acid such as citric acid, succinic acid, and tartaric acid greatly enhanced the browning reaction of ginseng but all treatments of mixture of glucose, glutamic acid, and glucose+glutamic acid with fumaric acid decreased the browning reaction except the treatment of fumaric acid only. The addition of ascorbic acid in concentration of greater than 0.1 M markedly accelerated the browning reaction and concurrently increased the red color, a characteristic color of quality red ginseng. Irradiation of ultraviolet light while drying red ginseng increased the brown color intensity in the first 5 days and thereafter decreased the brown color intensity.

• Applied Biological Chemistry
• /
• v.24 no.1
• /
• pp.29-39
• /
• 1981

Cooked spaghetti soaked in 10%, 20%, and 40% aqueous glycerine solutions for ten minutes absorbed sufficient glycerine to plasticize that spaghetti during and after subsequent drying. The plasticizing action of the glycerine prevented fissuring(checking) and surface corrugation of the spaghetti at elevated drying temperature and large wet-bulb dry-bulb temperature difference. The drying temperature and the wet-bulb dry-bulb differences up to which such protection was provided as the glycerine soak concentration increased. Despite the reduction in drying rate, the drying time required to produce spaghetti with a water activity of 0.65 (the level normally required for stability) decreased as glycerine content increased. At high frying temperatures glycerine addition increased the extent of browning and shortened the period required to induce detectale browning, but in all instances browning started well after the product $a_w$ reached the 0.65 value required for the completion of drying. Because glycerine addition reduced drying times at any given set of drying conditions and permitted the use of higher drying temperatures, relatively low levels of glycerine addition (e.g. 0.15 kg glycerine/kg dry spagetti) can shorten spagnetti drying times by roughly 80% and perhaps by as much as 93%.

• The Journal of the Convergence on Culture Technology
• /
• v.4 no.4
• /
• pp.331-335
• /
• 2018

Zantedeschia spp. calla is very popular as a cut flower. It is very important to establish a micro propagation system through plant tissue culture with the problem that colored calla with various colors are low in natural reproduction rate and vulnerable to high temperature. In this study, we conducted the experiment by adding taurine to improve the growth of calla plant. When 20 mg/L of taurine was added with plant growth effect, 54.0 % of the cases of multiple shoots and 17.2 times of fresh weight were the most effective. Taurine 20 mg/L treatment showed 16.0 % and 39.2 %, respectively, than the untreated control. Taurine may contribute to mass propagation of elite breeding lines as well as an improvement of farm income by positively influencing the overall growth of calla plants, thereby positively affecting the establishment of the micro propagation system of calla shoot tips.

• Applied Biological Chemistry
• /
• v.37 no.5
• /
• pp.379-384
• /
• 1994

Casein or soybean protein was subjected to the reaction with caffeic acid-tyrosinase system at $30{\sim}35^{\circ}C$ pH 6.8 with aeration for 5 hr. The effects of the modified proteins on male Wistar rats were studied by pair-feeding of a cholesterol-free diet for 2 weeks. Significant decrease in protein digestibility for the rats fed with the modified proteins was observed. The feeding of modified protein from casein caused an enlargement of caecum. The concentration of serum cholesterol and triglyceride in the rats fed with modified proteins were mostly unchanged against the rats fed with untreated proteins. These results suggest that the decrease in protein digestibility induced by enzymic browning-reaction did not cause the decrease in concentration of serum cholesterol.

• Applied Biological Chemistry
• /
• v.30 no.1
• /
• pp.71-76
• /
• 1987

The mutagenicity and desmutagenicity on enzymatic browning reaction products which obtained from prunes salicina (yellow) enzyme and polyphenol compounds were carried out. In the rec-assay on Bacillus subtilis strains H17 and M45, the enzymatic browning reaction products of pyrogallol, hydroxyhydroquinone, 3,4-dihydroxytoluene and catechol of $10^{-2}M$ did not showed mutagenicity. In the effects of various metal ions on the rec-assay, the enzymatic browning reaction products of pyrogallol showed mutagenic activity by $Fe^{3+},\;Mn^{2+},\;Zn^{2+},\;Ni^{2+}$ and $Al^{3+}$. In the enzymatic browning reaction products of hydroxyhydroquinone, $Cu^{2+},\;Mn^{2+}$ and $Pb^{2+}$ were effected in mutagenic action and the enzymatic browning reaction products of catechol was effected in mutagenic action by $Mn^{2+}$. In the DNA-breaking action of enzymatic browning reaction products of pyrogallol, hydroxyhydroquinone, 3,4-dihyroxytoluene and catechol did not show, DNA-breaking action. In the effects of various metal ions on the DNA-breaking action of enzymatic browning reaction products, $Cu^{2+}$ showed DNA-breaking action. In the mutagenicity test on Sal. typhimurium strains TA98 and TA 100 with S-9 mix, 4 kinds of browned substances did sot shove muragenicity, all the browned substances showed strong desmutagenic activity in the presence of benzo $({\alpha})-pyrene$ with S-9 mix.

• Applied Biological Chemistry
• /
• v.39 no.5
• /
• pp.384-388
• /
• 1996

This research was conducted to investigate the effective methods for browning inhibition on yam (Dioscorea aimadeimo) during dehydration by physical and chemical pretreatments. Moisture, crude protein, crude fiber and N-free extract contents of yam were 81.17%, 1.43%, 0.29% and 15.81%, respectively. Yams were sliced to 0.5 cm thickness and placed to single and poly layer in plastic tray, and then changes of their weights were measured during air dehydration at $50^{\circ}C,\;65^{\circ}C,\;and\;80^{\circ}C$. The dehydration time reaching to optimum moisture level for the pulverization of the yam slices were 10, 6, 3 hours(single layered) and 12, 7, 5 hours(multi layered) at the respective temperature. To inhibit browning at $80^{\circ}C$ air dehydration, water and steam blanching, microwave treatment effects were investigated on yam slices for 30 sec. and 60 sec. Steam blanching for 30 sec. was comparatively effective to inhibit browning of yam slices. Yam slices were immersed in single and combined browning inhibitor solutions and evaluated for browing degree during dehydration by the values of Hunter L, a, b and ${\Delta}E$. The most effective pretreatment to inhibit browning of yam slices was immersion In the solution containing 500 ppm of citric acid and 1000 ppm of cysteine for 1 min.