In order to investigate the optimal UVB (ultraviolet B) treatment conditions for vitamin D2 enhancement of freeze-dried ear mushroom, sample size (below 300 μm~whole), UV treatment temperature (30~60℃), treatment density (6.25~50.0 mg/cm2) and the samples mixing frequency (1~32 times) were treated differently. After that, chromaticity, vitamin D2 and ergosterol (vitamin D2 precursor) contents were investigated. As a result of the investigating, effective UVB treatment conditions for vitamin D2 enhancement are as follows. The sample sizes were 2~4 mm and finely crushed pieces. The treatment temperatures were 50℃ and 60℃. The treatment density was 12.5 to 25.0 mg/cm2, and the number of sample mixing was 8 times or more. As the amount of vitamin D2 increased by UVB treatment, the ergosterol content generally tended to decrease. However, under some UVB treatment conditions, the vitamin D2 content was not high despite the decrease of ergosterol content. Under the conditions set in this experiment, it was possible to obtain ear mushrooms with enhanced vitamin D2 up to 26,968.7 μg/100 g. Therefore, it is thought that the ear mushroom is highly likely to be used as a vitamin D source and nutritionally fortified food ingredient.
To apply UV-C as a non-heating sterilization method to increase the microbiological safety of fresh seedless watermelon products, reductions in E. coli and quality changes by treatment dose (0, 2, 4, 8, 14, 20 kJ/m2) were investigated. The pH, sugar content, and hardness of watermelon inoculated with E. coli were not significantly different according to the UV-C treatment dose, but the polyphenol content was significantly decreased compared to the controls (425.4 GAE μg/g F.W.). When treated with 2 and 4 kJ/m2, the lycopene content was 31.6 and 30.9 μg/g F.W., respectively, which was increased compared to the controls (28.5 μg/g F.W.). The arginine and citrulline content was also significantly increased compared to the controls. The number of E. coli was significantly decreased compared to the controls following UV-C treatment. Considering the degree of E. coli reduction, lycopene content, arginine content, citrulline content, and UV-C irradiation time, subsequent experiments were conducted by selecting a UV-C treatment dose of 2 kJ/m2. The results of confirming the degree of reduction in the number of E. coli colonies by a single treatment and combined treatment with UV-C 2 kJ/m2 and 70% ethanol showed that the combined treatment was most effective as colonies were decreased by 2.3 log CFU/g compared to the controls. Therefore, it is judged that UV-C 2 kJ/m2 radiation and combined treatment with 70% ethanol could be applied as a non-heating sterilization method for fresh watermelon slices.
This study was conducted to effectively supplement vitamin D and increase the consumption of ear mushroom based on the investigation of the quality characteristics of cookies containing ear mushroom supplemented with vitamin D. Cookies were made of 0%, 1%, 3%, and 5% ear mushroom powder treated by ultraviolet B. Increased addition of ear mushroom powder led to a decrease in the bulk density of the dough as well as a spread factor, color value, and hardness of the cookies. There was no significant difference in the loss rate, but the water content of the dough and cookies was increased. The total polyphenol content of cookies added with 1~5% ear mushroom powder was higher than that of the 0%. The DPPH free radical scavenging activity of cookies added with 5% ear mushroom powder (23.8%) was 2 times higher than that of the 0% (10.9%). The vitamin D2 content of cookies added with 5% ear mushroom powder (835.5 μg/100 g D.W.) was 44 times higher than that of the 0% (19.0 μg/100 g D.W.). Consequently, ear mushroom powder is considered to be suitable for the production of functional cookies because of high values of antioxidant activity and vitamin D2 content.
The purpose of this study was to determine the difference in vitamin B6 content according to the varieties, regions, and harvest times of vegetables and fruits in Korea using high performance liquid chromatography. We verified the accuracy of the analytical method with standard reference material 1849a and achieved reliability for internal analysis quality control with a mixture of cereal, whole wheat, and flour. As a result of the analysis, vitamin B6 contents (μg/100 g) were 6.9~86.5 in peppers, 5.1~17.2 in paprika, 4.4~5.0 in strawberries, 4.0~52.9 in tomatoes, 7.7~7.8 in Chinese cabbage, 17.3~23.3 in radishes, 13.4~37.6 in apples, 2.3~12.7 in peaches, and 3.7~12.7 in grapes. In general, the difference in vitamin B6 content showed by varieties, harvest times, and regions. Peppers showed the most difference as 79.6 μg/100 g among the varieties, and apples showed a difference as 22.8 μg/100 g by regions. According to the harvest times in grape ‘Mihwang’, there was a difference of 7.5 μg/100 g. We will collect an amount of nutritional data on various food materials, and continue to build a reliable and integrated nutritional database. And then the database will be used in the 10th revision of the Korean Food Composition Table.
To examine the possibility of ear mushroom (EM) as a source of natural vitamin D, the UVB (ultraviolet B) was treated according to sample drying status, drying methods before UVB treatment and harvest time. And then, vitamin D2 and ergosterol contents were investigated. According to the sample drying status, the vitamin D2 contents of fresh and freeze-dried EM (whole) increased to 4,634.4~4,780.9 μg/100 g D.W. (dry weight) under UVB dose 52.5~70.0 kJ/m2 and above 18,693.1 μg/100 g D.W. under above 105 kJ/m2, respectively. By drying methods before UVB treatment, vitamin D2 contents of EM powder (below 500 μm) that dried in the vinyl house and freeze-dryer increased to 4,886.2~5,132.9 μg/100 g D.W. under above 105 kJ/m2 and 17,103.7 μg/100 g D.W. under 70 kJ/m2, respectively. Ergosterol content decreased with increasing UVB dose in all experiments. According to the harvest time, vitamin D2 content under UVB dose 210 kJ/m2 showed marked difference and in order of June, July, August, October and April. As for the results, the optimum harvest time, drying method before UVB treatment, sample size, UVB dose for the EM contained high vitamin D2 content were June, freeze-drying, whole, and 105 kJ/m2, respectively.
Vinegar is a widely used acidic seasoning and can be manufactured using a variety of methods and basic materials such as grains, wheat, and fruits. It was produced through an acetic acid fermentation process carried out by acetic acid bacteria. These bacteria not only produce a variety of metabolic compounds but also alter the acidity and flavor of the product. Some vinegar also contains antioxidants, antineoplastic compounds, and other bio-metabolites, which can have a beneficial effect on health. This study was conducted to investigate the quality of fermentation black rice vinegar produced by fermented Omija (Schizandra chinensis Bail.) extract for improving vinegar’s preference. The total polyphenol content and DPPH scavenging activity of the vinegar created with fermented Omija extract were 317.5 ㎍/㎖ and 84.6%, respectively. But, the vinegar without Omija extract was 239.3 ㎍/㎖ and 72.5%, respectively. Glucose content of the vinegar added with the extract was 3.55∼4.17%, fructose content was 2.23∼2.71%, citric acid content was 4.23∼5.38% and malic acid content was 0.27∼0.62%. Glucose, fructose, citric acid and malic acid contents of the black rice vinegar added with the extract were higher than those of the vinegar without the Omija extract. The content of essential free amino acids in the vinegar added with the extract was 32.8∼42.7 mg% and GABA content was 0.45∼1.72 mg%. The vinegar with the fermented extract showed antimicrobial activity against Escherichia. coli, Bacillus subtilis and Pseudomonas aeruginosa.