• Title/Summary/Keyword: fermentation

Search Result 7,939, Processing Time 0.033 seconds

Bacterial Contamination and Its Effects on Ethanol Fermentation

  • Chang, In-Seop;Kim, Byung-Hong;Shin, Pyong-Kyun;Lee, Wan-Kyu
    • Journal of Microbiology and Biotechnology
    • /
    • v.5 no.6
    • /
    • pp.309-314
    • /
    • 1995
  • Samples were collected from a commercial ethanol production plant to enumerate the bacterial contamination in each step of a starch based ethanol production process. Though the slurry of raw material used in the process carried bacteria with various colony morphology in the order of $10^4$ per ml, only the colonies of white and circular form survived and propagated through the processes to the order of $10^8$ per ml at the end of fermentation. Almost all of the bacterial isolates from the fermentation broth were lactic acid bacteria. Heterofermentative Lactobacillus fermentum and L. salivarius, and a facultatively heterofermentative L. casei were major bacteria of an ethanol fermentation. In a batch fermentation L. fermentum was more detrimental than L. casei to ethanol fermentation. In a cell-recycled fermentation, ethanol productivity of 5.72 g $I^{-1} h^{-1}$ was obtained when the culture was contaminated by L. fermentum, whilst that of the pure culture was 9.00 g $1^{-1} h^{-1}$. Similar effects were observed in a cell-recycled ethanol fermentation inoculated by fermentation broth collected from an industrial plant, which showed a bacterial contamination at the level of 10$^8$ cells per ml.

  • PDF

Effect of Bamboo (Pseudosasa japonica Makino)Leaves on the Physicochemical Properties of Dongchimi (대나무(이대)잎이 동치미의 발효 중 이화학적 특성에 미치는 영향)

  • 김미정;장명숙
    • Korean journal of food and cookery science
    • /
    • v.15 no.5
    • /
    • pp.459-468
    • /
    • 1999
  • The purpose of this study was to evaluate the effect of bamboo(Idae) leaves on the taste and preservation of Dongchimi. Dongchimi was prepared by the method described in the literatures and fermented at 10$^{\circ}C$ for 75 days. The amounts of bamboo leaves used to cover the Donchimi was 1, 3, 5 and 7% of radish weight. Total vitamin C content increased gradually in the initial stage of the fermentation periods, and then it decreased gradually. Regardless of the amount of bamboo leves, the reducing sugar content increased gradually from the initial stage of fermentation increased rapidly after 8 days of fermentation. As the amount of bamboo leaves increased, the reducing sugar content was retained longer, which reflected the retardation of Dongchimi fermentation. The free amino acid contents in all of the Dongchimi samples were in order of arginine > glutaric acid > aspartic acid > alanine at the initial period of fermentation, but the order changed to arginine > alanine > glutamic acid > valine as fermentation proceeded over 23 days. Among the five non-volatile organic acids identified, the levels of malic acid and citric acid were decreased during fermentation, while those of lactic acid, fumaric acid, and succinic acid were increased. There was a significant increase in lactic acid, succinic acid, malic acid, and citric acid contents during fermentation. The content of water soluble pectin(WSP) was higher than other pectins at the initial stages, but the content of WSP decreased as fermentation proceeded.

  • PDF

Effect of Fermentation Temperature on Free Sugar, Organic Acid and Volatile Compounds of Kakdugi (깍두기의 발효숙성온도가 유리당, 유기산 및 향기성분에 미치는 영향)

  • 장명숙;김성단;허우덕
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.27 no.1
    • /
    • pp.16-23
    • /
    • 1998
  • Effect of Fermentation temperature on the changes of chemical components in Kakudgi during fermentation was investigated by measuring free sugar, organic acid and volatile compounds up to 57 days at several temperatures. The mannitol was increased in palatable period in contrast with those of other free sugars. The higher the initial fermentation temperature was and the longer the initial fermentation time at 2$0^{\circ}C$ was, the faster the second increasing period was and the less the initial contents was. Lactic acid was increased 6~31 times from a little amount at the initial period. The higher the initial fermentation temperature was and the more the increasing content was. But malic acid which was abundant(55.1% of total nonvolatile organic acid) in the initial fermentation period was remarkably decreased in the palatable period. The change of the sulfides among the volatile compounds was remarkable. Methyl allyl sulfide which was a little in the initial fermentation period was remarkably increased in the final fermentation period, and the correlation coefficients between the content of methyl allyl sulfide and aroma in sensory evaluation were high. It could be suggested that the fermentation temperature should be set to 4$^{\circ}C$ after fermentating at 2$0^{\circ}C$ for 36 hours in the view point of keeping the Kakdugi taste and quality well because of high content of free sugar and nonvolatile organic acids.

  • PDF

Investigation into the Ecological and Natural Dyeing with Medicinal Plants after Fermentation by NURUK and the Effect of Natural Additives

  • Park, Youngmi
    • Textile Coloration and Finishing
    • /
    • v.24 no.4
    • /
    • pp.260-269
    • /
    • 2012
  • The aim of this study was to develop higher-value added dyeing materials with the fermentation-dyeing -mordanting system using only the natural ingredients by integrating traditional fermentation techniques with traditional dyeing technique. Nuruk, which is used mainly to ferment traditional foods, was used as a fermenting agent to ferment 5 different types of materials. Acidic burnt alum and alkaline calcium hydroxide were used as natural mordants. The dyeability checked after fermentation showed that both cotton and silk mordanted with Gardenia jasminoides did not show notable changes, and 10 days of fermentation was found to be appropriate. Sophora japonica L. performed better on cotton materials mordanted with slaked lime, and alkaline mordants were found to be more effective than acidic ones. With Rheum coreanum, a fermentation period of more than 24 days ($5^{th}$ fermentation) worked best on cotton material, showing a 5 fold increase in the K/S value after the $5^{th}$ slaked lime fermentation than with no fermentation. Rhus javanica L. was found to increase the color fastness to gentle washing and the fastness to light was found to possess 4 means that natural dyed fabric have the highest level of durability, the grade 1 the lowest level of fastness.

Studies on the Cephalosporin C Biosynthesis by Fermentation

  • Lee, Kang-Man;Ryu, Dewey Doo-Young
    • Archives of Pharmacal Research
    • /
    • v.2 no.2
    • /
    • pp.79-83
    • /
    • 1979
  • Using cephalosporium acremonium ATCC 14553, we studied on the important factors in fermentation. Those factors were :carbon and nitrogen sources, methionine effect, absorbent effect, fermentation variables in a batch fermentation variables in a batch fermentation, effect of reuse of its cellular biomass as a reusable nutrient, and 2, 4-dinitrophenol effect on cephalosprin C production.

  • PDF

Pervaporative Butanol Fermentation Using a New Bacterial Strain

  • Park, Chang-Ho
    • Biotechnology and Bioprocess Engineering:BBE
    • /
    • v.1 no.1
    • /
    • pp.1-8
    • /
    • 1996
  • Fermentation processes for the production of butanol had an economic importance in the first part of this century. Today butanol is commercially produced from the Oxo reaction of propylene because relatively low priced propylene during the cracking of petroleum. Efforts have been made during the past decade or two to improve the productivity of butanol fermentation processes. It includes strain improvements, continuous fermentation processes, cell immobilization and simultaneous product separation. This review introduces a new butanol fermentation process using pervaporative product separation and a new bacterial strain producing less amount of organic acids. This review also compares the new process with chemical processes. This kind of new fermentation process may be able to compete with the chemical synthesis of butanol and revitalize the butanol fermentation process.

  • PDF

Fermentation for Liquid-type Yogurt with Lactobacillus casei 911LC

  • Ko, I.H.;Wang, M.K.;Jeon, B.J.;Kwak, H.S.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.18 no.1
    • /
    • pp.102-106
    • /
    • 2005
  • This study was carried out to find the attributes for liquid-type yogurt with Lactobacillus casei 911LC during 72 h fermentation at $37^{\circ}C$. The pH decreased up to 32 h and plauteaued thereafter, and the titratable acidity increased up to 40 h. The growth of lactic acid bacteria sharply increased with $3.5{\times}10^7$ cfu/ml up to 40 h of fermentation and slowly decreased thereafter. The free amino acids produced during fermentation reached the maximum value at 44 h and gradually decreased thereafter. Bitterness sensory scores were the highest at 44 h of fermentation. In the result of electrophoresis, the band mostly disappeared at 72 h fermentation. The present data showed that the range of optimum fermentation time for liquid-type yogurt using Lactobacillus casei 911LC was from 40 to 44 h.

Characteristics of Sunroot (Helianthus tuberosus) Fermentation with boundary condition (발효조건에 따른 돼지감자의 발효시스템)

  • Chung, Sung Won;Woo, Ji Hee;Choi, Won Sik
    • Journal of the Korean Society of Industry Convergence
    • /
    • v.20 no.5
    • /
    • pp.411-417
    • /
    • 2017
  • In this study, Sunroot was used as material in the fermentation process. Sunroot are widely distributed in Korea, The main component is composed of inulin. Fermented vinegar stimulates digestion in the body, as well as to relieve stress is a cause of increasing the neurotransmitter-Serotonin of the body. Therefore, we conducted fermentation studies using sunroot. This research conducted seven days, and the pH and brix value analysis was done every 12 hours during fermentation process. The experimental results show that the fermentation product under blender treatment is better than cutting treatment and without cutting treatment. Initial brix 25% is the best treatment for fermentation because produce fermentation product with a good taste and aroma than other treatment.

Bifidobacterium Fermentation of Rice and Apple Pomace Mixture (쌀과 사과박 혼합물을 이용한 Bifidobacterium발효제품의 개발)

  • 이주연;박종현;장학길;목철균
    • Microbiology and Biotechnology Letters
    • /
    • v.27 no.4
    • /
    • pp.333-338
    • /
    • 1999
  • This study was aimed to develop a value-added fermented products from rice and apple pomace using Bifidobacterium fermentation. The Bifidobacterium fermentation system of the mixture of rice and apple pomace was developed, and the physicochemical properties of the products were investigated. After 4 different bifidobacteria were compared for their fermentation capability and sensory properties of the fermented product, Bifidobacterium FBD-13 and FBD-22 were selected as appropriate strains for the fermentation of saccharified rice solution(SRS). The optimum inoculation level was 2% and the optimum fermentation time was 42 hrs. When wet apple pomace(WAP) was added to SRS, it contributed to the improvement of sensory properties of the fermented products and the optimum mixing ratio was 40% WAP and 60% SRS in weight. For the fermentation of the mixture of WAP and SRS, Bifidobacterium FBD-27 and FBD-22 were selected as suitable strains.

  • PDF

Fermentation of Acidic Beverage with Dropped Peach (복숭아 낙과를 이용한 초산음료의 발효)

  • 김순동;이재석;김미경
    • Journal of the East Asian Society of Dietary Life
    • /
    • v.4 no.3
    • /
    • pp.135-146
    • /
    • 1994
  • The study was conducted to research the desirable method for fermentation of acidic beverage in the farmhouse using peach dropped at harvesting periods. Step by step fermentation(SSF), complex fermentation after crushing of the fruit(CCF), complex fermentation after slicing of the fruit(SCF) and natural fermenation added yeast only after slicing of the fruit(SYNF) were compared. The brief stationary fermentor for complex fermentation in the farmhouse was made in this experiment. The ability of acid production, flavor, taste and color were measured by sensory evaluation and mechanical methods. The quality of vinegar by SYNF was the most desirable, estimated by the color, the flavor, the content and composition of sugar, and of organic acids, and which was a suitable fermentation method for the farmhouse. The strains of acetobacter SYNF-1, 2 and 3 were isolated from the SYNF vinegar, and the SYNF-1 was a main strain.

  • PDF