• Korean Journal of Food Science and Technology
• /
• v.39 no.4
• /
• pp.432-437
• /
• 2007

In this study, we examined the conditions for an auto-aging system placed within a kimchi refrigerator for optimal fermentation, and to prolong the storage time of kimchi. Various characteristics of kimchi fermented at different temperatures ($5-23^{\circ}C$) were compared. We observed that the higher the fermentation temperature, the less desirable the overall acceptability of the product. To establish the time point in which to convert the fermentation mode to the storage mode, kimchi was stored at $-1^{\circ}C$ for 1 week once it reached the designated acidity (0.4, 0.6, and 0.8%). The results indicated that the lower the kimchi acidity, the higher the sensory score. The storage temperature of $-1^{\circ}C$ was not low enough to retard microorganism growth completely; however, the kimchi stored at $-2{\pm}0.5^{\circ}C$ became frozen. Accordingly, $15^{\circ}C$ and $-2{\pm}0.5^{\circ}C$ are suggested as the fermentation and storage temperatures for the kimchi refrigerator, respectively. A kimchi acidity of 0.4% can be used as an index for the time point to convert fermentation to storage. Subsequently, the time required for the fermentation course can be calculated based on this.

• Journal of the East Asian Society of Dietary Life
• /
• v.8 no.2
• /
• pp.162-173
• /
• 1998

The effect of soybean addition to the preparation of Jeung-Pyun(Korean fermented rice cake) and the fermentational characteristics of Jeung-Pyun dough were determined. Jeung-Pyun dough composed of rice 100g, soybean 20g, water 40g, salt 0.8g, sugar 15g and Tak-ju 30g was fermented for up to 20hours. the numbers of total microbes, yeasts and lactic acid bacteria in the dough during fermen-tation increased rapidly during 5 hours of fermentation, but Leuconostoc mesenteroides during 7 hours of fermentation, Generally, there were many more microbes in the Jeung-Pyun dough with soybeans than in the Jeung-Pyun dough with rice. The volume of 7 hour fermented Jeung-Pyun was most massive, especially in the soybean added Jeung-Pyun. 1% dextran-added rice Jeung-Pyun, the volume of steamed cake was increased more than that of rice Jeung-Pyun, but is was not as bulky as in the soybean-added cake. In the sensory evaluation of the test cake products, the 7 hour fermented cake was preferred by nost. As for instrumental characteristics, the 7 hour feremented Jeung-Pyun showed the lowest values for hardness and elasticity, brittleness and chewiness. The rice Jeung-Pyun showed were stored at 2$0^{\circ}C$ the hardness, brittleness and cohesiveness of rice Jeung-Pyun were respectively increased rapidly after 5 days of storage. The cohesiveness, elasticity, brittleness, chewiness, gumminess of both rice Jeung-Pyun and soybean-added Jeung-Pyun were decreased with storage time.

• Journal of Animal Environmental Science
• /
• v.6 no.2
• /
• pp.65-72
• /
• 2000

This study was conducted to investigate the effects of artificial filaments equipped in the aeration tank of aerobic·fermentation system on the removal efficiency of swine wastes which were fermented an aerobically and thus containing high nitrogen. Two aerobic fermentation system each consist4s of 4 tanks ; storage tank, 1st and 2nd aeration tank and settling tank were run before and one or three weeks after equipment of artificial filament in the aeration tanks. Total solids concentration tended to increase by aerobic fermentation in all running periods. However, decreased(P<0.05) total nitrogen concentration was shown three weeks after the equipment of artificial filament. Ammonia nitrogen concentration also largely decreased(p<0.05) in both running periods of one and three weeks after equipment of artificial filaments. These results suggest that the artificial filaments may improve the removal efficiency of nitrogen in swine wastewater containing high nitrogen during aerobic fermentation.

• Food Science and Biotechnology
• /
• v.17 no.4
• /
• pp.692-699
• /
• 2008

The effects of wasabi stalk on the taste and storage characteristics of baechukimchi were assessed in the final product. Wasabi stalk was added in different ratios: 0, 1, 3, 5, or 7%(w/v) of Chinese cabbage. As the fermentation progressed, the pH of the product dropped. Total acidity increased in all treatments during fermentation. The total vitamin C content increased during the first 8 to 13 days of fermentation. Reducing sugar decreased in all treatment as fermentation continued. The numbers of total cells and lactic acid bacteria increased until they peaked, and then began decreasing as fermentation continued. With regard to acceptability characteristics, the 3% treatment was most favored. With simple regard to the quantitative level of wasabi stalk addition, the 3% treatment was most appropriate under all testing conditions. In conclusion, stalk seems to be an economical and natural additive which has effects on extension of the shelf life of baechukimchi.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.38 no.6
• /
• pp.787-794
• /
• 2009

In this study, a new method for extending storage-life and palatability of Betula platyphylla sap by applying lactic acid bacteria fermentation was developed. The fluids of saps were filtered through 0.22 ${\mu}m$ membrane filter and each fermented by 8 different lactic acid bacteria which are Lactobacillus acidophilus, Lactobacillus brevis, Leuconostoc mesenteroides, Leuconostoc lactis, Lactococcus lactis, Pediocossus pentosaceus, Pediococcus dextrinicus, Streptococcus thermophilus. All the tested lactic acid bacteria except P. dextrinicus grew fast up to $10^6{\sim}10^7cfu/mL$ levels and lowered pH down to about pH 4 levels in 48 hours in both saps. The produced organic acids and lowered pH level inhibited the growth of spoilage microorganisms almost completely for 2 weeks during storage at room temperature. Addition of xylitol in the saps before fermentation accelerated the growth of lactic acid bacteria and increased the sweetness and overall taste of final product. The filtration process did not affect the mineral compositions of Betula platyphylla saps. Also the compositions and amounts of minerals showed very minor differences before and after fermentation in Betula platyphylla saps inoculated with L. acidophilus. By applying lactic acid fermentation to extend storage-life of tree saps instead of heat treatment, it was possible to keep natural minerals in active forms without any modifications.

• Food Science and Preservation
• /
• v.17 no.1
• /
• pp.30-35
• /
• 2010

Salt composition may affect the quality of Kimchi. We examined the quality of Kimchi prepared using different types of salt (Korean purified salt, Korean solar salt without bittern, Korean solar salt, Chinese purified salt, Chinese solar salt, and Australian solar salt). Kimchi was fermented for 7 days at $20^{\circ}C$. Following fermentation, the pH of Kimchi decreased during storage, but total acidity and salinity values increased. The type of salt used did not affect quality. Total bacterial counts were 4.18-4.37 log CFU/g initially, and increased markedly during fermentation. Lactic acid bacterial counts were 3.42-4.91 log CFU/g initially, but 7.31-7.79 log CFU/g after 7 days of storage. The sensory characteristics of Kimchi during storage did not vary with the type of salt used in fermentation.

• Journal of the East Asian Society of Dietary Life
• /
• v.23 no.5
• /
• pp.546-560
• /
• 2013

In this study, a natural fermentation starter formulation was developed for manufacturing Korean bread products by substituting baker's yeast with naturally fermented blueberry starters. As the incubation time of the blueberry extracts increased, the pH and total titratable acidity increased. The sweetness (brix%) of blueberry extracts containing various amounts of sugar were higher than the other sample. The result of alcoholicity for naturally fermented blueberry extracts, the fermented blueberry extract containing 20% sugar was highest. Lactic acid bacteria counts increased until the 4th day; however, it decreased from the 5th day, and viable yeast counts increased consistently until the 5th day. The volume for naturally fermented blueberry extracts increased as the incubation time increased. As the fermentation time of blueberry starters increased, the pH of bread dough decreased. The RVA analysis conveyed that wheat flour retrogradation was retarded by increasing the blueberry starter content. The weight of pan breads containing blueberry starters were higher than that of the control, while the volume, specific volume and baking loss rate were lower than those of the control. The moisture content of pan breads containing blueberry starter decreased as storage time increased. In analyzing the visible mold colony during 7 days of storage at $28^{\circ}C$, mold growth in pan breads containing the blueberry starter was retarded. The hardness of breads containing blueberry starters were significantly increased as storage time increased. The breads containing 50% naturally fermented blueberry starter have acceptable sensory properties. In conclusion, these results indicated that 50% of natural fermentation blueberry starter could be very useful as a substitute for yeast when making naturally fermented bread.

• Asian-Australasian Journal of Animal Sciences
• /
• v.27 no.7
• /
• pp.937-945
• /
• 2014

Green and black tea by-products, obtained from ready-made tea industry, were ensiled at $10^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$. Green tea by-product silage (GTS) and black tea by-product silage (BTS) were opened at 5, 10, 45 days after ensiling. Fermentation characteristics and nutrient composition, including tannins, were monitored and the silages on day 45 were subjected to in vitro ruminal fermentation to assess anti-nutritive effects of tannins using polyethylene glycol (PEG) as a tannin-binding agent. Results showed that the GTS and BTS silages were stable and fermented slightly when ensiled at $10^{\circ}C$. The GTS stored at $20^{\circ}C$ and $30^{\circ}C$ showed rapid pH decline and high acetic acid concentration. The BTS was fermented gradually with moderate change of pH and acid concentration. Acetic acid was the main acid product of fermentation in both GTS and BTS. The contents of total extractable phenolics and total extractable tannins in both silages were unaffected by storage temperatures, but condensed tannins in GTS were less when stored at high temperature. The GTS showed no PEG response on in vitro gas production, and revealed only a small increase by PEG on $NH_3$-N concentration. Storage temperature of GTS did not affect the extent of PEG response to both gas production and $NH_3$-N concentration. On the other hand, addition of PEG on BTS markedly increased both the gas production and $NH_3$-N concentration at any ensiled temperature. It can be concluded that tannins in both GTS and BTS suppressed rumen fermentation, and tannins in GTS did more weakly than that in BTS. Ensiling temperature for both tea by-products did not affect the tannin's activity in the rumen.

• Microbiology and Biotechnology Letters
• /
• v.43 no.2
• /
• pp.120-125
• /
• 2015

In this study, the probiotification of mango juice was carried out by lactic acid bacteria fermentation. Mango juice fermentation was performed at 30℃ for 72 h under micro-aerophilic conditions. The microbial population, pH, titrable acidity, sugar, and organic acid metabolism were measured during the fermentation period and the viability of the strains was determined under the storage conditions at 4℃ for 4 weeks. The lactic acid bacteria reduced the pH to as low as 3.2 from 4.5 within 72 h of fermentation. The substrate concentration was reduced to 5.8% (w/v) from 12% (w/v). Lactobacillus plantarum exhibited the fastest utilization of sugar and reduction of pH in the mango juice when compared to the other strains used. The viability of the cells was maintained at 1.0 × 10⁷ CFU/ml throughout the storage period. From this investigation, it can be concluded that mango juice is suitable for the production of probiotic beverage.

• Preventive Nutrition and Food Science
• /
• v.16 no.1
• /
• pp.74-82
• /
• 2011

The fermentation and quality characteristics of kimchi, made by adding different types of red pepper (semi-dried red pepper, fresh red pepper, dried red pepper) according to drying conditions, were examined for 15 days at $10^{\circ}C$ fermentation. The initial pH was approximately 5.65~5.72 in all groups, and the pH decreased with increasing fermentation time. The color value of a/b showed the highest in kimchi that made with semi-dried red pepper (SDRP-K). The color value of A remained at the initial level for 9 days, regardless of treatments. The color value had a tendency to decrease after 9 days. The lactic acid bacteria increased rapidly during 6 days of storage, but showed no difference among groups. The initial contents of malic acid and succinic acid were in 3.23~4.52 and 6.12~7.97 mg/mL and decreased during fermentation in all groups. The lactic acid and acetic acid were not contained in the beginning, but increased with increasing fermentation periods. The vitamin C content of SDRP-K was 5.20 mg/g, which was significantly higher compared with kimchi that made with dried red pepper (DRP-K), but which did not show any significant difference to kimchi that made with fresh red pepper (FRP-K). As a result of antioxidant activity in optimally ripened kimchi, both $DPPH^+$ and $ABTS^+$ scavenging activities were higher in SDRP-K than any other groups. As a result of the sensory evaluation, overall acceptability was highest in SDRP-K.