• Korean Journal of Food Science and Technology
• /
• v.45 no.2
• /
• pp.252-256
• /
• 2013

We tested the possibility of utilizing Korea domestic wheat (winter wheat variety "keumkangmil") as a source of vinegar production. After saccharification of the whole-wheat flour with wheat malt, the saccharized liquid undergoes alcoholic fermentation, followed by acetic fermentation. Acetic acid bacterium A8, which showed the highest acetic acid production (4.56%) with domestic wheat as substrate, was selected from conventional vinegars. The strain A8 was identified as Acetobacter pasteurianus A8 through phylogenetic study using 16S rDNA sequencing analysis. The optimal condition for the malt enzyme was found to be $15^{\circ}C$ for germination periods of 6 days; its amylase activity was 608.4 U. Acetic acid production from domestic wheat substrate supplemented with 5% ethyl alcohol reached 5.8% after 24 days of static fermentation at $30^{\circ}C$ with a seeding rate of 5%.

• Korean Journal of Food Science and Technology
• /
• v.35 no.6
• /
• pp.1150-1154
• /
• 2003

The characteristics of a strain that contaminates the manufacturing of rice vinegar by Acetobacter pasteruianus was invetigated. Conditions for inhibiting pellicle formation and growth of the contaminant, which occurs during static culture and storage, were also observed. Examining the morphological, cultural, and physiological characteristics and measuring the amount of cellulose production during static culture for 14 day, we found that the strain was known to be Acetobacter xylinum. No growth was observed below $10^{\circ}C$ as well as over $40^{\circ}C$. Also, the extent of growth was limited when the concentrations of ethanol, NaCl, and acetic acid were more than 10%, 1.5%, and 7%, respectively.

• Korean Journal of Food Science and Technology
• /
• v.30 no.5
• /
• pp.1203-1208
• /
• 1998

To utilize astringent persimmon (Diospyros kaki, T.) effectively, response surface methodology (RSM) was applied to optimize and monitor the vinegar fermentation conditions by two stage fermentation. In the first stage, the fermentation conditions for maximum alcohol content was $20.51\;^{\circ}brix$ in sugar concentration of astringent persimmon, 139.52 rpm in agitation rate, and 94.88 hr in fermentation time. When sugar concentration of astringent persimmon was $14\;^{\circ}brix$, maximum alcohol content predicted by response surface methodology was 7.1% at agitation rate of 40 rpm and fermentation time of 120 hr. In the second stage, the fermentation conditions for maximum acidity was 224.40 rpm in agitation rate, 176.07 hr in fermentation time. Alcohol content and acidity predicted at the optimum conditions were similar to experimental values.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.8
• /
• pp.1264-1269
• /
• 2014

This study investigated the effects of rice starch addition, including native, acetylated, and hydroxypropy-lated rice starch, on the quality characteristics of instant fried noodles. Compared to 100% wheat flour (control), flours containing acetylated or hydroxypropylated rice starch showed reduced initial pasting temperatures as well as peak and breakdown viscosities as determined using a Rapid Visco-Analyzer (RVA). The addition of acetylated and hydroxylated rice starch as well as native rice starch increased cooked weight, volume, and water absorption of the fried noodles compared to control noodles. The addition of native rice starch tended to increase softness of noodles, whereas addition of acetylated or hydroxypropylated rice starch significantly lowered hardness, gumminess, and chewiness values. The results of the sensory evaluation indicate that noodles containing rice starch showed improved sensory characteristics such as color, appearance, flavor, taste, and texture. Especially, acetylated rice starch could be used to improve eating quality of instant fried noodles.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.43 no.2
• /
• pp.250-257
• /
• 2014

To develop vinegar with immature Citrus unshiu (IC), bacterial strains with high acetic acid-producing capabilities were isolated and identified, after which their quality characteristics, total phenolic and total flavonoid contents, and antioxidant activities were measured. Five bacterial strains were isolated from naturally fermented C. unshiu, and three were identified as Acetobacter fabarum (A. sp. RIC I) and A. pomorum (A. sp. RIC II, V). A. sp. RIC V showed the highest acetic acid-producing capability and was thus chosen as the candidate strain for further acetic fermentation using IC juice. Vinegars made with 30, 35, and 40% IC juices showed acidities of 5.38, 5.38, and 5.32% and fermentation efficiencies of 73, 72, and 70%, respectively. The fermentation periods required to reach greater than 5% acidity were 11, 9, and 9 days for vinegars containing 30, 35, and 40% IC juices, respectively. Fructose and glucose contents of the vinegars increased along with total organic acid contents including acetic acid, with increasing IC juice contents. Total phenolics were 1,546.6 and $230.9{\mu}g$ GAE/mL, whereas total flavonoids were 1,004.7 and $175.1{\mu}g$ QE/mL in vinegars made with IC and mature C. unshiu (MC) juices, respectively. DPPH free radical scavenging activities were 29% and 5%, ABTS radical scavenging activities were 62.0% and 17.9%, SOA scavenging activities were 60.9% and 41.7%, and XO scavenging activities were 32.5% and 5% in vinegars made with IC and MC juices, respectively. Therefore, vinegars made with 35% and 40% IC juices using A. sp. RIC V as the acetic acid fermentation strain showed potent antioxidant activities with greater total phenolic and flavonoid contents, promoting their use as functional vinegars.

• Korean Journal of Food Science and Technology
• /
• v.4 no.2
• /
• pp.112-115
• /
• 1972

In the cource of investigation on L-glutamic acid production, acetate assimilating bacteria were isolated from natural sources. Among them, the strain No. 1214 was selected and characterized as a strain related to the genus Brevibacterium according to the standard method of taxonomy. This strain could grow in the acetate medium and accumulated a considerable amount of L-glutamic acid (22 g/L).

• Journal of Food Hygiene and Safety
• /
• v.38 no.6
• /
• pp.508-516
• /
• 2023

The consumption of enoki mushrooms has been associated with cases of listeriosis produced by Listeria monocytogenes, highlighting the significance of sanitizing food-contact surface, such as the velcro used in welding processing of enoki mushrooms, to ensure microbial safety. We investigated the inhibitory activity of nine chemical disinfectants at regular concentrations against L. monocytogenes isolated from a mushroom farm environment. The bacterial suspension was prepared in phosphate buffered saline and mushroom extract broth and inoculated onto the velcro surface. After inoculation, most disinfectants reduced the initial 8 log CFU/coupon concentration by less than 2 log CFU/coupon during a 5-min treatment. Slightly acidic hypochlorous water showed a reduction of approximately 4 log CFU/coupon when tested for more than 30 min at the maximum allowable concentration of 200 mg/L. Sodium hypochlorite solution showed a reduction of approximately 5 log CFU/coupon when used at 100 mg/L for 60 min. Peracetic acid, at the maximum allowable concentration of 300 mg/L, showed the most effective reduction of 5 log CFU/coupon or more when the surface was treated with 37.5 mg/L for 30 min. These results indicate that peracetic acid can be used as the disinfectant strategy to control cross-contamination of L. monocytogenes on the velcro surface of plastic wrappers used in the welding processing of enoki mushrooms.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.33 no.3
• /
• pp.593-597
• /
• 2004

This study was conducted to investigate the quality characteristics of liquid calcium acetate (LCAs) and solid calcium acetate (SCAs), Br-LCA, Pe-LCA and Ap-LCA as liquid form, Br-SCA, Pe-SCA and Ap-SCA as solid form. Calcium acetate was prepared by reacting of vinegars [brown rice (Br), persimmons (Pe) and apple (Ap)] and ash of black snail in order to obtain natural water soluble calcium resources. The pHs of the vinegars for preparing calcium acetate (CA) were the range of 2.34 ∼ 3.06, and the contents of the ash of black snail which reacted to 100 mL of the vinegars were 20.43∼23.50 g. The yields of solid CAs from 100 mL of the vinegars were 11.02∼13.01 g. The colors of liquid and solid CAs were light yellow in Ap-LCA and Ap-SCA, brown in Br-LCA and Br-SCA, dark brown in Pe-LCA and Pe-SCA. Calcium contents of Br-LCA, Pe-LCA and Ap-LCA were 3.02, 2.06 and 2.30% (w/v), and those of Br-SCA, Pe-SCA and Ap-SCA were 27.15, 16.31 and 19.48% (w/w), respectively. The solubilities of the solid CAs were 36.82 ∼ 39.92% (w/v) in distilled water, 32.05 ∼ 39.04% (w/v) in Soju, 13.12 ∼ 18.65% (w/v) in thick soysauce, 38.35 ∼ 38.90% (w/v) in ionic beverage, 33.47 ∼ 35.58% (w/v) in yoghurt, while the solid CAs formed the curds in soymilk and milk. The sour and bitter taste of the CAs were lower, while the astringent taste, fishy flavor and savory taste were higher than those of standard CA.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.36 no.3
• /
• pp.361-365
• /
• 2007

This study was conducted to improve the Prunus mume vinegar production. The most suitable concentration of the Prunus mume juice was 6%. Static fermentation was a more suitable process for acetic acid fermentation of the Prunus mume vinegar than shaking fermentation. Major components of the organic acids were acetic, citric, tartaric and malic acid at 4.2, 1.2, 0.3, and 0.1%, respectively. Also, major components of the free sugars were glucose and fructose, and 80.96 mg% of asparagine was included in the Prunus mume vinegar as a main free amino acid. Alcohol components of the Prunus mume vinegar were n-propyl alcohol, iso-butyl alcohol, n-butyl alcohol, iso-amyl alcohol, and n-amyl alcohol.

• Research in Plant Disease
• /
• v.20 no.3
• /
• pp.227-233
• /
• 2014

The mixture (MX) of acetic acid (AA) and lactic acid (LA) was examined for its effectiveness in the control of the pine wood nematode Bursaphelenchus xylophilus contaminated in cymbidium culture medium. Nematode mortality in vitro was nearly 100% in AA and MX at the concentrations of 5.0-1.0% (pH 2.6 - 4.2) and in LA only at 5.0% (pH 3.5), but lowered at concentrations of 0.5-0.1% (pH 5.1-6.9) more significantly in LA than AA and MX. MX of most concentrations caused higher nematode mortality than the average response to AA and LA. All treatments of MX (0.5% and 0.25%), fosthiazate (standard and double concentrations) and culture dilution of Paenibacillus polymyxa GBR-1 ($10^7$colony-forming units/ml) reduced significantly the nematode populations in the cymbidium culture medium, compared to non-treatment control, with no significant difference among the treatments. No phytotoxicity occurred in all treatments. pH of the medium with the time after treatment and growths of 2-year-old cymbidium were not significantly different among treatments. Considering the safety and price of the organic acids, use of MX in the processes for culturing cymbidium may be a practically reliable and eco-friendly way in the control of the quarantine nematode in cymbidium.