• Journal of Microbiology and Biotechnology
• /
• 제25권1호
• /
• pp.26-32
• /
• 2015

Four types of straw, namely, soybean, wheat, corn, and rice, were investigated for use in lactic acid production. These straws were mainly composed of cellulose, hemicellulose, and lignin. After pretreatment with ammonia, the cellulose content increased, whereas the hemicellulose and lignin contents decreased. Analytical results also showed that the liquid enzymatic hydrolysates were primarily composed of glucose, xylose, and cellobiose. Preliminary experiments showed that a higher lactic acid concentration could be obtained from the wheat and soybean straw. However, soybean straw was chosen as the substrate for lactic acid production owing to its high protein content. The maximum lactic acid yield (0.8 g/g) and lactic acid productivity (0.61 g/(l/h)) were obtained with an initial reducing sugar concentration of 35 g/l at 30℃ when using Lactobacillus casei (10% inoculum) for a 42 h fermentation period. Thus, the experimental results demonstrated the feasibility of using a soybean straw enzymatic hydrolysate as a substrate for lactic acid production.

• Journal of Dairy Science and Biotechnology
• /
• 제37권3호
• /
• pp.196-205
• /
• 2019

본 연구는 돼지감자 분말을 첨가한 발효유 제조의 이화학적 분석을 통해서 돼지감자를 식품소재로써 활용하고자 첨가량에 따른 발효 품질특성을 분석하였다. 돼지감자 분말 1%, 3%, 5% 첨가 발효유 중 5% 첨가구가 산 생성이 가장 우수하였고, 유산균 수도 가장 높게 생장하였다. 또한, 유산 생성이 활발하였고, 항산화 활성과 항균활성도 높았다. 점도는 5% 첨가구에서 가장 높았는데, 물성적인 측면에서 고려할 사항으로 사료된다. 돼지감자분말 첨가 발효유 생산이 유가공산업의 활성화에 기여하길 기대한다.

• 한국조리학회지
• /
• 제20권4호
• /
• pp.37-48
• /
• 2014

본 연구에서는 쌀가루와 호화쌀가루의 첨가량과 처리를 달리한 요구르트를 제조하여 반응표면분석법(RSM)을 이용하여 쌀가루 첨가량의 관능적 최적점을 갖는 조성을 확인하고 이 때의 유산발효 특성을 연구하고자 하였다. RSM을 통해 발효액 조성이 최적화 된 2가지(쌀가루, 호화쌀가루)의 요구르트 발효 중 pH, 산도, 당도, 점도, 유산균 수 검사를 통하여 유산발효 특성을 알아보았다. 쌀가루와 호화쌀가루 첨가 요구르트 모두에서 발효시간이 증가함에 따라 pH가 감소하는 경향을 보였으며, 적정산도는 발효시간이 증가함에 따라 점점 증가하는 경향을 보였다. 당도는 발효시간이 증가함에 따라 감소하는 경향을 보였는데 발효되는 동안 당이 분해 감소되고 젖산발효에 의한 것으로 여겨진다. 점도는 발효 6시간에서 가장 높았으며 발효 완료 시점인 10시간에서는 발효 시작 전보다 높은 점도를 보였다. 쌀가루와 호화쌀가루 첨가 요구르트의 유산균수는 7.43~9.00 log CFU/mL으로 호상요구르트의 식품 규격 적정치 범위 이상으로 측정되어 미분첨가가 요구르트 제조 시의 유산균수에 부합하는 것을 확인할 수 있었다. 또한 쌀가루 보다는 호화쌀가루를 첨가하였을 때 쌀의 첨가량도 늘릴 수 있으며, 점도에서도 좋은 결과를 보여 호화쌀가루를 이용한 요구르트는 쌀을 활용한 더 효과적인 기능성 유산발효제품이 될 수 있을 것으로 보였다.

• Asian-Australasian Journal of Animal Sciences
• /
• 제11권3호
• /
• pp.277-284
• /
• 1998

This experiment was carried out to study the effects of lactic acid bacteria (LAB) inoculation and addition of cell wall degrading enzymes on the fermentation characteristics and chemical compositions of Italian ryegrass silage. An inoculant LAB with or without a cell wall degrading enzyme of Acremoniumcellulase (A), or Meicellulase (M) or a mixture of both (AM), was applied to 1 kg of fresh Italian ryegrass sample. The treatments were control untreated, LAB-treated (application rate $10^5$ cfu/g fresh sample), LAB+A 0.005%, LAB + A 0.01%, LAB+A 0.02%, LAB + M 0.005%, LAB + M 0.01%, LAB + M 0.02%, LAB+AM 0.005%, LAB + AM 0.01% and LAB+AM 0.02%. The sample was ensiled into 2-L vinyl bottle silo, with 9 silages of each treatment were made (a total of 99 silages). Three silages of each treatment were incubated at 20, 30 and $40{^{\circ}C}$ for an approximately 2-months storage period. All silages were well preserved as evidenced by their low pH values (3.79-4.20) and high lactic acid concentrations (7.71-11.34% DM). The fermentation quality and chemical composition of the control untreated and the LAB-treated silages were similar, except that for volatile basic nitrogen (VBN) content was lower (p < 0.05) in the LAB-treated silages. LAB + cellulase treatments improved the fermentation quality of silages by decreasing (p < 0.01) pH values and increasing (p<0.01) lactic acid concentrations, in all of cellulase types and incubation temperatures. Increasing amount of cellulase addition resulted in further decrease (p < 0.01) of pH value and increases (p < 0.01) of lactic acid and residual water soluble carbohydrate (WSC) concentrations. LAB + cellulase treatments reduced (p<0.01) NDF, ADF, hemicellulose and cellulose contents of silages compared with both the control untreated and LAB-treated silages. LAB + cellulase treatments did not affect the silage digestibility due to fact of in vitro dry matter digestibility (IVDMD) was similar in all silages. The silages treated with cellulase A resulted in a better fermentation quality and a higher rate of cell wall reduction losses than those of the silages treated with cellulases M and AM. Incubation temperature of $30{^{\circ}C}$ seemed to be more suitable for the fermentation of Italian ryegrass silages than those of 20 and $40{^{\circ}C}$.

• Journal of Dairy Science and Biotechnology
• /
• 제32권1호
• /
• pp.37-45
• /
• 2014

Benzoic acid is widely used in the food industry as a preservative in acidic foods, owing to its antimicrobial activity against various bacteria, yeasts, and fungi. Benzoic acid occurs naturally in different foods such as fruits, vegetables, spices, and nuts as well as in milk and dairy products. Lactic acid bacteria convert hippuric acid, which is naturally present in milk, to benzoic acid; therefore, the latter could also be considered as a natural component of milk and milk products. Benzoic acid is also produced during the ripening of cheese by the propionic acid fermentation process that follows lactic acid fermentation. This paper, we provide basic information regarding the systematic control of natural benzoic acid levels in raw materials, processing intermediates, and final products of animal origin.

• Journal of Microbiology and Biotechnology
• /
• 제3권4호
• /
• pp.266-269
• /
• 1993

The production of free non-volatile and volatile organic acids in Kimchi during fermentations at 30, 20 and $5^{\circ}C$, were determined by gas chromatography. The order in the amount of non-volatile organic acid, soon after preparation, was malic, citric, tartaric, pyroglutamic, oxalic, lactic, succinic and ${\alpha}-ketoglutaric$ acids. The major non-volatile acids at the optimum ripening time were malic, tartaric, citric and lactic acids, and as the temperature was lowered, the amount of lactic, succinic, oxalic, pyroglutamic and fumaric acids increased, while that of malic and tartaric acids decreased. The order in the amount of volatile acids at the beginning was acetic, butyric, propionic and formic acids. Among these acids, acetic acid was significantly increased in its amount during fermentation and the Kimchi fermented at low temperature produced more acetic acid than that fermented at high temperature.

• 한국식품조리과학회지
• /
• 제23권2호통권98호
• /
• pp.227-234
• /
• 2007

Potato kimchi, fermentation was carried out at $10^{\circ}$C for 15 days using various ratios of potato to kimchi (2.5%, 5%, 10%). The samples were determined according to the fermentation time, pH, acidity and growth of lactic acid bacteria in potato kimchi. The addition ratio of potato to kimchi had little effect on the pH, acidity or growth of lactic acid bacteria in potato kimchi. In comparison to baechu kimchi and mul-kimchi, the pH, acidity and growth of lactic acid bacteria was better in potato kimchi than in the other kimchi samples. The in vitro anticancer effect of potato kimchi was investigated using human cancer cells, AGS human gastric adenocarcinoma cells and HT-29 human colon adenocarcinoma cells. MTT assay revealed that the methanol extract of potato kimchi showed the highest anticarcinogenic effects.

• 한국식품저장유통학회지
• /
• 제3권1호
• /
• pp.33-38
• /
• 1996

To investigate the food preservative effects of mustard seed(Brassica juncea), mustard seed were added to Kimchi. Titratable acidity of Kimchi treated with mustard seed was higher than that of non-treated control at initial stage, but it was lower than control after 2 days of fermantation. The number of bacteria and lactic acid bacteria increased rapidly at the initial stage of fermentation and reached plateau by 2 days of fermentation. The number of bacteria and lactic acid bacteria of Kimchi treated with mustard seed was lower than that of control, and the more mustard seed added the less bacteria and lactic acid bacteria were observed.

• 한국미생물·생명공학회지
• /
• 제22권5호
• /
• pp.550-556
• /
• 1994

For an extension of the palatable stage in Kimchi which was limited by further lowering pH as the fermentation proceeds, the starter culture of bacteriocin-producing Enterococcus faecium DU 0267 obtained from Kimchi was added at the preparation time, and pH, bacteriocin activity, growth of lactic acid bacterial group and gas production in Kimchi were examined during the fermentation at 10, 20 and 30$\circ$C . The pH of Kimchi fell rapidly to 4.0~4.2 in the early fermentation stage, and then, has gone down very slowly throughout further fermentation. The lactic acid bacte- ria, particularly lactobacilli and leuconostoc, were remarkably slower in its growth than those in the control. Although the patterns of these change during fermentation at different temperatures were similar, these effects by the addition of starter were enhanced at 10 and 20$\circ$C. The bacteriocin activity was increased rapidly during log phase of the bacteriocin producer strain in the early fermentation stage of Kimchi and reached their maximum after fermentation at 10$\circC, for 8 days and at 20 or 30$\circ$C for 2 days. Thereafter, the activity disappeared quickly. The gas production by fermentation was also suppressed considerably, and their volume produced after fermentation at 20$\circ$C for 14 days corresponded to 60% of those of the control.

• 한국식품조리과학회지
• /
• 제15권5호
• /
• 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.