• The Korean Journal of Food And Nutrition
• /
• v.36 no.1
• /
• pp.58-68
• /
• 2023

This study investigated the quality characteristics of beyolmijang prepared with corn (steamed and roasted corn) with different pretreatments and simultaneously added starter (Bacillus velezensis JH1). pH decreased, whereas total acidity showed a tendency to increase. The moisture content decreased slightly according to the fermentation period. In color, the L and b values decreased in all samples, whereas the a value showed a tendency to increase significantly. In microorganisms, sample D had more lactic acid bacteria, whereas the mold content was lower. The total polyphenol content was highest at six weeks in sample E, and other samples showed a tendency to decrease over eight weeks. Antioxidant activity increased significantly. In particular, the content in sample E was significantly higher. Reducing sugar showed a tendency to increase as the fermentation period increased. The highest content was found in sample C containing roasted corn at six weeks of fermentation. Amino nitrogen and ammonia nitrogen content increased in all samples. As a result of electronic tongue, sample E prepared with steamed corn, roasted corn, and lactic acid bacteria showed a low salty taste, sour taste, and high umami taste and was considered a good material for the development of byeolmijang.

• Journal of Practical Agriculture & Fisheries Research
• /
• v.25 no.4
• /
• pp.158-164
• /
• 2024

With the steady growth in the scale of the domestic traditional liquor industry, the interest in makgeolli has also been increasing. As the demand for makgeolli increases, interest in manufacturing differentiated makgeolli by adding additional raw materials such as fruits is increasing. In this study, makgeolli with low storage persimmon juice was manufactured, and the sweet taste of persimmon was imparted without adding sweeteners. Unsweetened, high-quality persimmon makgeolli with an alcohol content of 15% or more was manufactured and its quality characteristics were analyzed. Yeast was selected after producing fermented yeast by treating domestic isolated yeast and commercial yeast. Upon producing fermented yeast, persimmon makgeolli was manufactured by varying the amount of persimmon juice added to the fermented yeast. As a result of analyzing the quality characteristics of persimmon makgeolli, the pH was 4.02-4.25, the total acid (citric acid, %) was 0.30-0.43, the amino acidity (glycine, %) range was 0.05-0.15, and the alcohol content (%) was 15.64-18.48.(p<0.05). Reducing sugar (%) was 1.82-12.68 and total sugar (%) was 1.41-10.42, exhibiting a tendency to increase as the amount of reducing sugar and total sugar and the amount of juice added increased (p<0.05). Considering the sensory characteristics, a sample with 50% persimmon juice added showed a significantly higher residual sugar content, and the residual sugar content had a positive effect on the sensory characteristics. Therefore, 50% persimmon juice was added when making persimmon makgeolli. It is suitable for high-quality, non-sweetened persimmon makgeolli that preserves the taste of persimmon, which suits the consumers'taste.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.39 no.9
• /
• pp.1384-1390
• /
• 2010

In this study, we investigated the quality of glasswort (Salicornia herbacea L.) mixture fermented by Aspergillus oryzae at $30^{\circ}C$ for 7 days. Changes of pH, titratable acidity, amino-nitrogen content, reducing sugar content, activities of $\alpha$-amylase and protease and number of mold were determined in the course of the fermentation. Angiotensin converting enzyme (ACE) inhibition activities and electron donating ability (EDA) were measured after 7 days fermentation. The pH lowered from 6.19~6.22 into the level of 5.41~6.08 after fermentation for 7 days. Titratable acidity increased from 0.59~0.68 into the highest level of 0.95~1.13% after 6 days fermentation. Furthermore, the amino-nitrogen content increased from 128.0~167.2 mg% to 159.4~209.0 mg% after fermentation for 7 days. For the reducing sugar content, it decreased from 2.0~5.9% into the level of 0.4~1.1% during 7 days fermentation. The number of molds decreased from $10^7\;CFU/g$ to approximately $10^6\;CFU/g$ after 5 days fermentation. $\alpha$-Amylase activity showed from the beginning of the fermentation in all samplings, but protease activity reached the value of food code standards after 5 days of fermentation. ACE inhibition activities were slightly increased from 9.5~16.6% to 19.3~22.7% and electron donating ability were slightly increased from 55.6~57.8% to 60.9~62.7% after 7 days of fermentation.

• Korean Journal of Food Science and Technology
• /
• v.33 no.4
• /
• pp.444-450
• /
• 2001

Kochujang, fermented hot pepper paste, was treated with combined high hydrostatic pressure and heat. Viable cell counts and chemical compositions of Kochujang were determined as a function of high pressure processing conditions such as temperature, pressure and time, and during storage for 120 days at $37^{\circ}C$. Viable cell counts were decreased with the increase of temperature, pressure and time. Viable cell counts in the treated Kochujang were decreased up to $0{\sim}3$ log cycle with the temperature of $49{\sim}73^{\circ}C$, $0{\sim}3$ log cycle with the pressure of $380{\sim}680\;MPa$, and $2{\sim}5$ log cycle with the time of $10{\sim}70\;min$, compared with the untreated. pH, titratable acidity, amino nitrogen, reducing sugar and ethanol content in the treated Kochujang were comparable to the untreated regardless of the treatment condition. Hunter L, a and b values in the treated Kochujang were higher than those of the untreated. Viable cell counts were decreased with the increase of the storage period at $37^{\circ}C$. Viable cell counts in Kochujang treated at 380 MPa/30 min were decreased up to 2 log cycle from $1.8{\times}10^6\;to\;1.94{\times}10^4\;CFU/g$ after 120 days of storage, while those at 680 MPa/70 min were not detected after 60 days from the initial stage of $4.00{\times}10^1\;CFU/g$. pH, amino nitrogen and ethanol content were decreased, and titratable acidity were increased significantly as the increase of the storage period. Hunter L, a and b values also decreased significantly. The changes in physicochemical properties of Kochujang treated at 680 MPa/70 min were greater than those at 380 MPa/30 min.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.37 no.8
• /
• pp.1030-1036
• /
• 2008

In Korea, many types of traditional grape wine have existed starting from seven hundred years ago and horse-blossom-like-grape (mayu-podo) was mainly cultivated. Korean traditional wine (KTW) was manufactured by a unique method in which grape juice-added porridge made from glutinous rice was fermented by nuruk as a starter for brewing. Unfortunately, KTW making was discontinued in 20th century; thus, restoration of Korean wine culture is needed. KTWs were prepared by four traditional methods, and their qualities were compared to commercial wine made by sugaring grape juice. Ethyl alcohol contents, total acidity, pH and amino acid of the four KTWs were $9.2{\sim}11.2%$, $0.93{\sim}1.20\;mg$/100 mL, $3.02{\sim}3.48$ and $0.80{\sim}0.88\;mg$/100 mL respectively. The KTWs showed higher values in total acidity and amino acid than those of commercial grape wine. KTWs were rich in maltose, acetic acid and lactic acid. L, a and b value in Hunter's color value ranged $3.59{\sim}3.69$, $20.63{\sim}38.06$, and $1.20{\sim}1.56$, respectively. Sensory quality properties in color, flavor, taste and overall of KTWs were not different from commercial dry wine. Contents of total phenolic compounds and free radical scavenging activity using DPPH of KTWs were $599.6{\sim}652.2\;mg$/100 mL and $50.59{\sim}56.75%$, respectively.

• Journal of Food Hygiene and Safety
• /
• v.25 no.4
• /
• pp.360-366
• /
• 2010

Doenjang (fermented soybean paste) is one of the korean traditional fermented soybean product which is consumed with cooked rice as a soup or paste. During the fermentation, soybean protein hydrolyzed into amino acids and various peptide, and various organic acids by mirobes related and enzymes produced by meju fermentation. Some commercial products locationally samples give more sour taste than normal due to abnormal fermentation which the reasons are not clear. Three samples that gave sour taste organoleptically were collected and analyzed their characteristics such as pH, moisture content, acidity and microbial counts. The pH of the sour sample were lower than the normal with higher acidity as pH 5.39 (normal) to pH 4.36 (S2) and 15.80 ml of(0.lN NaOH consumed) to 21.80 ml (S1) respectively. Salt and moisture contents were different with sour and normal Doenjang as 16.38% (normal) to 8.92% (S3) in salt and 55.94% (normal) to 49.34% (S1) in moisture content. Total viable counts were $4.1{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2), and $3.4{\times}10^8$ (normal) to $8.0{\times}10^5$ (S2) in acid producing microbes at BCP plate. Yeast and mold were not detected. The composition of acids as mainly lactic acid and acetic acid of sour Doenjang. Total free amino acids content were lower the sour Doenjang than the normal.

• Food Science and Preservation
• /
• v.23 no.5
• /
• pp.680-688
• /
• 2016

This study analyzed the changes in physicochemical components of Astragalus membranaceus (AM) fermented with Phellinus linteus. Moisture content, pH, total acidity, total reducing sugar content, extraction yield, free sugar content, free amino acid and isoflavonoid (calycosin, formononetin) were investigated. The moisture content was increased during fermentation with Phellinus linteus. The pH level increased while the total acidity significantly decreased during fermentation. The reducing sugar content were in the range of 0.32~0.61%. The extraction yield using water was higher than that using 80% ethanol. The major free sugars were identified as glucose, fructose, sucrose and the content of free sugars decreased through fermentation. However, the glucose and sucrose contents of the water extracts were increased. In addition, the free amino acid increased significantly during fermentation. Finally, calycosin and formononetins contents in water extracts of after 30 days of AM fermentaion with Phellinus linteus were (3.91 mg/100 g) and (1.38 mg/100 g), respectively. These results suggest that fermentation with Phellinus linteus could be used to increase the bioactivity of AM. The mycelium-fermented AM could be a valuable source of functional material and edible resource for industry.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.44 no.1
• /
• pp.137-144
• /
• 2015

Kyejang is a Korean traditional beverage manufactured from medicinal plants and fruits using honey, sugar, or starch in cold water. In this study, cinnamon-containing kyejang, which is a type of beverage Jang, was reproduced based on Imwonsibyukji's method published in 1827 in the Korean literature. Kyejang made by nuruk, cinnamon, and medicinal plants was prepared at various temperatures and periods. Kyejang was assayed for physiochemical properties (pH and acidity), contents of metabolites (organic acids, sugars, and amino acids), and sensory characteristics (aroma and taste). During fermentation, content of organic acids (e.g. lactic acid, acetic acid, and shikimic acid) increased, which lowered pH, increased acidity, and increased intensity of sour taste. In the case of free sugars, fructose and maltose levels decreased while glucose and mannitol levels increased during fermentation periods, and sweetness decreased. The main amino acid in kyejang was tryptophan, followed by asparagine, proline, and arginine. The sensory evaluation score of overall preference was highest for kyejang which was fermented at $20^{\circ}C$ for 3 days. The results will be provide the basic data of fermentation conditions for standardized manufacturing process of kyejang.

• Korean Journal of Food Science and Technology
• /
• v.41 no.5
• /
• pp.541-546
• /
• 2009

The objectives of this study were to evaluate the physico-chemical and sensory characteristics of a Korean traditional alcoholic beverage (yakju) prepared using different nuruk (Korean-style koji) concentrations and yeasts such as the fusant FA776 and Saccharomyces cerevisiae KOY-1, respectively. The fusant FA776, which has alcohol-fermenting and starch-utilizing properties, was formed by Saccharomyces cerevisiae KOY-1 and Saccharomyces diastaticus KCTC1804. The fermentation trial was conducted in a 5 L lab-scale jar at $25^{\circ}C$. The maximum alcohol production of the K-100 and F-50 reached levels of 135.0 mg/mL and 119.4 mg/mL, respectively. The pH values were in a range of 4.3-4.5. Total acidity was in a range of 0.47-0.60%. Organic acids and amino acids were analyzed in order to evaluate variations in its composition and content via HPLC analysis. Organic acids including lactic acid, citric acid, malic acid, and pyruvic acid, and 16 kinds of amino acids, including aspartic acid, were detected in all treatments. K-100 showed the highest amino acid contents, whereas F-50 exhibited the lowest amino acid contents. Volatile flavor components such as phenylethyl alcohol, isoamyl alcohol, 2-methylthiophane, isobutyl alcohol, and ethyl succinate were detected as a major component in all treatments, as determined via gas chromatography. The results of our sensory evaluation demonstrated that Yakju fermented by the FA776 fusant yielded more favorable results than S. cerevisiae KOY-1.

• Journal of the Korean Society of Food Science and Nutrition
• /
• v.41 no.1
• /
• pp.79-86
• /
• 2012

This study was performed to investigate the physiochemical properties and anti-diabetic effect of yacon vinegar by two-step fermentation. Yacon was matured at room temperature for 20 days. The sugar content of yacon juice prepared from mature yacon was approximately $14^{\circ}Brix$. In the first stage, yacon wine was produced from the juice at $28^{\circ}C$ for 6 days. In the second stage, acetic acid fermentation was conducted at $30^{\circ}C$ and 200 rpm for 6 days to produce yacon vinegar with 4.75% acidity. The major free sugars of yacon vinegar were glucose and fructose at 2,072.12 mg% and 463.95 mg%, respectively. The acetic acid content was the highest of the major organic acids at 3,881.44 mg%. The total free amino acid content was 62.88 mg% with the main free amino acids being proline, ${\gamma}$-amino-n-butyric acid and ornithine. The major minerals of yacon vinegar were Ca, K and Mg. The in vivo anti-diabetic activity of yacon vinegar was investigated in high-fat diet (HFD)/streptozotocin (STZ)-induced diabetic mice. Diabetic mice were administered orally with 10% yacon juice and two yacon vinegars (5% and 10%) at a dose of 7 mL/kg body weight once per day for 4 weeks. Five% yacon vinegar improved the fasting blood glucose levels and glucose tolerance test significantly compared to the diabetic control group (p<0.05). Yacon vinegar increased the pancreatic C-peptide concentration in a dose-dependent manner. These results show that 5% yacon vinegar has a more potent effect on ameliorating hyperglycemia than 10% yacon juice.