• The Korean Journal of Food And Nutrition
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• v.14 no.5
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• pp.385-390
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• 2001

The enzyme activity and organoleptic properties of Korean pickled cucumber were studies for their changes during fermentation. The Korean pickled cucumber were prepared by blanching and high temperature soaking in salt solution and trehalose treament. The results showed that the effect of combined heat and trehalose treatment significantly reduced the fermentation rate and softening rate of texture while a rather rapid fermentation was for those preserved with salt. The effect of terhalose treatment enhanced fermentation and it was significantly reduced softening rate of texture by 2% treatment. The sensory evaluation of Korean pickled cucumber was found that combined heat treatment with blanching and hot solution had a positive effect for reduction of softening of cucumber tissue, however, odor and taste were not significantly affected. This study suggested that combined heat and trehalose treament might have potential for affording protection against softness of cucumber tissue during the fermentation time.

• Journal of Microbiology and Biotechnology
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• v.27 no.1
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• pp.101-111
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• 2017

The task of improving a fungal strain is highly time-consuming due to the requirement of a large number of flasks in order to obtain a library with enough diversity. In addition, fermentations (particularly those for fungal cells) are typically performed in high-volume (100-250 ml) shake-flasks. In this study, for large and rapid screening of itaconic acid (IA) high-yielding mutants of Aspergillus terreus, a miniaturized culture method was developed using 12-well and 24-well microtiter plates (MTPs, working volume = 1-2 ml). These miniaturized MTP fermentations were successful, only when highly filamentous forms were induced in the growth cultures. Under these conditions, loose-pelleted morphologies of optimum sizes (less than 0.5 mm in diameter) were casually induced in the MTP production cultures, which turned out to be the prerequisite for the active IA biosynthesis by the mutated strains in the miniaturized fermentations. Another crucial factor for successful MTP fermentation was to supply an optimal amount of dissolved oxygen into the fermentation broth through increasing the agitation speed (240 rpm) and reducing the working volume (1 ml) of each 24-well microtiter plate. Notably, almost identical fermentation physiologies resulted in the 250 ml shake-flasks, as well as in the 12-well and 24-well MTP cultures conducted under the respective optimum conditions, as expressed in terms of the distribution of IA productivity of each mutant. These results reveal that MTP cultures could be considered as viable alternatives for the labor-intensive shake-flask fermentations even for filamentous fungal cells, leading to the rapid development of IA high-yield mutant strains.

• Applied Biological Chemistry
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• v.39 no.5
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• pp.398-402
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• 1996

This study was carried out to compare the fermentation rates of Dongchimi as affected by fermentation temperature and salt concentration of brining solution. The Dongchimi was prepared by fermentation of the radish in salt solutions of 2.0, 3.2 and 5.1% NaCl respectively with addition of garlic, green onion, ginger at $4^{\circ}C,\;10^{\circ}C,\;20^{\circ}C$. The fermentation was classified into 3 steps of initial, intermediate and final stages according to pH changes and the rates of fermentation and color change were calculated from intermediate stage. The time reached equilibrium in hardness of radish and salt concentration and their equilibrated values were also compared. Fermentation rate became more rapid as fermentation temperature and salt concentration increased. The rates of Hunter color change of Dongchimi liquid were increased as the temperature increased. The 'L' values decreased slowly, and 'a' and 'b' values increased rapidly to maximum at the intermediate stage. The time required to reach equilibrium was reduced for both salt concentration and hardness of radish as the fermentation temperature increased. The equilibrated values of salt concentration were increased while those of hardness of radish were decreased as the temperature and salt concentration increased. The data obtained can be used for prediction of some of the major characteristics of Dongchimi during fermentation.

• The Korean Journal of Food And Nutrition
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• v.26 no.4
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• pp.678-684
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• 2013

This study measured the change of lactic acid bacteria during the ripening fermentation process of low salt fermented squid with no squid ink added. All study groups showed increase of Leuconostoc and rapid growth of total plate count at the beginning stage of ripening and the maximum microbial count showed at the optimum stage of ripening which gradually reduced after the optimum stage. It is believed that Lactobacillus occupied the major part of the total plate count after the optimum stage of the squid fermentation, and it was related to the quality after the optimized ripening stage. Streptococcus and Pediococcus were gradually increased until the optimum stage of the ripening, and then decreased rapidly. Yeasts were detected in the middle stage of the fermentation and rapid increase was shown after the last stage of the fermentation which suggests that yeasts participate in putrefaction of the low salt fermented squid. The change of lactic acid bacteria observed during the ripening fermentation of low salt fermented squid with squid ink added was that the total plate count increased until ripening middle stage but showed a tendency to slightly reduce after the middle stage. The length of time to reach the maximum value was longer than the no treatment groups. Among the lactic acid bacteria, Leuconostoc, Streptococcus and Pediococcus has increased until the middle stage of the ripening while Lactobacillus constantly increased to the end part of the ripening. Yeasts had no increasing in the early ripening stage, but after middle of the ripening, it started to increase. That kind of tendency was similar to the case of no treatment groups. However, the amount of lactic acid bacteria tended to be less than no treatment groups. The tendency of decreasing number of all bacteria in low salt fermented squid with squid ink added shows squid ink restricts the growth of all bacteria.

• Microbiology and Biotechnology Letters
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• v.32 no.4
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• pp.291-296
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• 2004

To produce functional and high nutritional chungkook-jang, an immuno-stimulating and rapid growing bacterium was isolated from one of Korean traditional food, chungkook-jang. The isolated bacterium was identified as Bacilpumilus and deposited in Korean Collection for Type Culture (KCTC 10461BP). The chungkook-jang fermented by JB-l has good taste and pleasant smell with high content of free amino acids, and the water extract of chungkook-jang showed 410% of immuno-stimulation activity at concentration of 2 mg/ml. The rapid fermentation in 16 h is achieved by inoculation of 20 ml culture broth of JB-l into 6 kg cooked soybean in commercial scale at $40^{\circ}C$.

• Journal of the Korean Society of Food Culture
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• v.14 no.5
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• pp.455-460
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• 1999

In order to establish the processing condition of salt-fermented liquefaction of sardine (Sardinops melanoslicta), effect of temperature, pH value, and concentration of salinity on crude enzyme activity of sardine viscera were investigated. The optimum temperature range of crude enzyme activity in sardine viscera was $45{\sim}50^{\circ}C$ and the optimum pH value of it was 9.8. According to the concentration of salinity increased the crude enzyme activity in sardine viscera decreased. The relationship between concentration of salinity (X) and the crude enzyme activity (Y) in sardine viscera is shown as follows; Y=-0.01363X+0.7676 (r=-0.88). For the purpose of processing conditions of rapid- and low salt-fermented liquefaction of sardine, changes of viable cell count, histamine content, and volatile basic nitrogen (VBN) in the chopped whole sardine with 8% NaCl during preheating process at $40^{\circ},\;45^{\circ}$ and $50^{\circ}C$ for 48 hrs were analyzed. During preheating, initial viable cell counts of chopped whole sardine were $10^{4-7}/g$, but they decreased $10^{1-5}/g$ after 48 hrs. Histamine contents during preheating process at $40^{\circ}\;and\;45^{\circ}C$ were gradually increased, whereas at $50^{\circ}C$ were almost the same level after 48 hrs. VBN contents were continuously increased during preheating, but preheating at $50^{\circ}C$ samples were lower level than that of $40^{\circ}\;and\;45^{\circ}C$ ones. For the purpose to accelerate the fermentation and liquefaction of chopped whole sardine, preheating at optimum temperature of crude enzyme activity for 48 hrs was useful processing method and the contents of viable cell count, histamine, and VBN were safety level for food sanitation.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.502-509
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• 1993

Changes in microflora and enzyme activities of 3 kinds of traditional kochujang were investigated during 6 months of fermentation. Tested kochujang included Sunchang kochujang prepared with glutinous rice, Boeun kochujang prepared with barley and Sachun kochujang prepared with wheat. The pH in Sunchang and Sachun kochujang showed a slighlt decrese during fermentation. In contrast, pH of Boeun kochujang decreased rapidly up to 90 days of fermentation and then leveled off thereafter. The final pH values of Sunchang, Boeun and Sachun kochujang were 4.7, 4.0, and 4.6, respectively. The viable cell counts of aerobic bacteria in Sunchang and Sachun kochujang did not show remarkable changes during fermentation, however, those in Boeun kochujang showed a rapid increase up to 60 days of fermentation and stabilized. On the other hand, the viable cell counts of anaerobic bacteria decreased after 120 days of fermentation. Yeasts were found in different traditional kochujang at different time during the first 60 days of fermentation. It was found that ${\alpha}-$, ${\beta}-$, and glucoamylase activities of Sachun kochujang were higher than those of Sunchang and Boeun kochujang during fermentation. Acidic and neutral proteases showed the highest activity during $30{\sim}60\;days$ and $60{\sim}90\;days$ of fermentation, respectively. Sunchang kochujang showed the highest activity of acidic protease followed in decreasing order by Sachun and Boeun kochujang. On the other hand, Boeun kochujang showed the highest activity of acidic protease followed in decreasing order by Sachun and Sunchang kochujang.

• Korean Journal of Food Science and Technology
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• v.26 no.3
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• pp.199-203
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• 1994

Software for refrigerator capable of both rapid fermentation and suitable storage of Kimchi was developed and its performance was investigated. Refrigerator system consists of an insulated fermentation room, heater, damper for the control of outer cold air and two sensors for recognizing temperature of heater and fermentation room, which control temperature and time period of affecting Kimchi fermentation. Effects of fermentation at different NaCl concentration and three fermentation function keys were studied; At key I, time which was elapsed to edible ripening state, pH 4.5 and total acid 0.6%, was about $3{\sim}4$, $4{\sim}5$ and $11{\sim}12$ days, respectively. At key II, time was about $2{\sim}3$, $3{\sim}4$, and $10{\sim}11$ days, and at key III, about 2, 3 and $9{\sim}10$ days, respectively. Effect of storage at three fermentation function keys was all maintained to the level of a palatable pH range until 14 days. Sensory evaluation of Kimchi showed also significant difference in a taste.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.520-527
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• 1987

This study was attempted to identify microorganisms in fermenting soybean curd residues (SCR). The changes in contents of free amino acids, nucleosides, reducing sugars, and oligosaccharides were also studied. The fermentation of SCR which was by change inoculation was carried out at $55^{\circ}C$ for 48 hrs. pH increased gradually during fermentation and isolated microorganisms were identified as Bacillus subtilis and Bacillus licheniformis. Moisture content decreased from 80.8% to 58.4% at 48 hrs of fermentation and other proximate composition did not show any changes during fermentation. The content of total free amino acids increased rapidly and the number and quantities of each amino acid analyzed also increased during the course of fermentation. Glutamic acid, phenylalaine, lysine and aspartic acid were rapidly liberated during fermentation. As to the changes of nucleotides, 5'-AMP little changed during the first 36 hrs but subsequently decreased to approximately 1/6 after 48 hrs of fermentation. On the other hand, 5'-IMP plus 5'-GMP did not show almost any change during the first 36 hrs but increased about 3.5 times at 48 hrs of fermentation. However, 5'-XMP was not detected. The reducing sugar level showed rapid and steady increase throughout the fermentation and that of stachyose plus raffinose decreased slightly. From these results, a possible way of utilization of fermented SCR was proposed as a substitute for soybean in meju preparation.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.9
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• pp.1276-1284
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• 2014

In southeastern regions of the US, herbage systems are primarily based on grazing or hay feeding with low nutritive value warm-season perennial grasses. Nutritious herbage such as annual ryegrass (Lolium multiflorum Lam.) may be more suitable for preserving as baleage for winter feeding even with more intensive production inputs. Emerging in-line wrapped baleage storage systems featuring rapid wrapping and low polyethylene film requirements need to be tested for consistency of storing nutritive value of a range of annual ryegrass herbage. A ryegrass storage trial was conducted with 24-h wilted 'Marshall' annual ryegrass harvested at booting, heading and anthesis stages using three replicated in-line wrapped tubes containing ten round bales per tube. After a six-month storage period, nutritive value changes and fermentation end products differed significantly by harvest stage but not by bale location. Although wilted annual ryegrass exhibited a restricted fermentation across harvest stages characterized by high pH and low fermentation end product concentrations, butyric acid concentrations were less than 1 g/kg dry matter, and lactic acid was the major organic acid in the bales. Mold coverage and bale aroma did not differ substantially with harvest stage or bale location. Booting and heading stage-harvested ryegrass baleage were superior in nutritive value to anthesis stage-harvested herbage. Based on the investigated nutritive value and fermentation characteristics, individual bale location within in-line tubes did not significantly affect preservation quality of ryegrass round bale silages.