Toxicodendron vernicifluum extract (TVE) was co-fermented by Saccharomyces cerevisiae and Lactobacillus plantarum EJ2014 to produce higher content of gamma-aminobutyric acid (GABA). The TVE was cultured at 30℃ for 2 days under static conditions with sucrose 5%, yeast extract 1%, and Saccharomyces cerevisiae starter 1%. The second lactic acid fermentation after the primary first yeast fermentation was performed at 30℃ for 7 days after adding monosodium L-glutamate (MSG) 2.5%, lactose 2.5% and lactic acid bacteria (LAB) starter 1%. The first fermented TVE showed pH 4.6, 0.1% acidity and viable cell counts of S. cerevisiae 7.63 log CFU/mL. After the second fermentation, co-fermented TVE showed pH 4.64, 0.68% acidity, and viable cell count of L. plantarum EJ2014 7.68 log CFU/mL. During the co-fermentation with S. cerevisiae and L. plantarum EJ2014, the MSG was completely converted, yielding 2.5% GABA. Conclusively, co-fermentation of TVE was successfully performed with S. cerevisiae and L. plantarum EJ2014, resulting in a higher production of GABA and probiotics. The final fermented TVE could be utilized as a multi-functional ingredient in food and bio-industries.

To construct a nutrient database that provides the mineral and ash compositions of commercial beverages, the mineral and ash contents in 24 kinds of commercial beverages were determined. The contents of Na, Ca, K, P, Mg, Fe, Mn, Zn, Cu and Cr were analyzed using inductively coupled plasma (ICP) optical emission spectrometry, whereas the contents of Se, I and Mo were analyzed using ICP mass spectrometry. The reliabilities of the analytical methods in the analyses of minerals and ash were confirmed using a control chart. The ash content of beverages was 0.08-1.71 g/100 g, exhibiting the highest ash content of green tea latte. The Na content of beverages differed considerably in the range of 2.16-141.03 mg/100 g, with yam tea and americano exhibiting the significantly highest and lowest amounts of Na, respectively. The lowest and highest values of the other minerals in the beverages were 2.98-130.49 mg Ca/100 g, 17.75-272.89 mg K/100 g, 1.86-76.27 mg P/100 g and 0.75-27.43 mg Mg/100 g. The micromineral content showed a wide range, with the highest content in yam tea (3.20 μg Se/100 g), dalgona coffee (3.50 μg Mo/100 g), vanilla milk shake (21.00 μg I/100 g), and green tea latte (11.95 μg Cr/100 g). This study revealed reliable mineral contents in commercial beverages for use in nutritional information and food composition databases.

In vitro luwak coffee was produced using enzyme-microbial complexes. The coffee quality of non-fermented coffee beans (NFC) and fermented coffee beans (FC) was compared. The total free amino acid content was higher in FC than in NFC. The levels of glutamic acid and γ-amino-n-butyric acid in NFC were higher than those in FC; however, the contents of essential amino acids, such as lysine, leucine, and valine, in FC were higher than in NFC. During fermentation, the sucrose content decreased, whereas the fructose and glucose contents increased (p<0.001). The chromaticity of the coffee extract showed higher lightness (L), redness (a), and yellowness (b) values in FC than those in NFC. The caffeine content was significantly lower in FC (696.94±0.04 μg/mL) compared to that in NFC (1,130.22±1.55 μg/mL) (p<0.001). Conversely, the polyphenol and chlorogenic acid contents were significantly higher ​​in NFC than in FC (p<0.001). Electronic nose analysis indicated considerable differences between the volatile aromatic components in NFC and FC. Sensory scores were significantly higher for FC than those for NFC. Therefore, the fermentation of coffee beans using enzyme-microbial complexes altered the chemical components, which promoted the Maillard reaction during the coffee bean roasting process. These results suggest the possibility of producing in vitro luwak coffee with better flavor and lower caffeine content.

Concrete has contributed to the development of modern architectural culture, but the cement as an adhesive agent for concrete produces large amounts of carbon dioxide emissions into the air during the manufacturing process. This study researches the practical use of structure, through the verification of structural stability, for geopolymer concrete. This is part of the development of core technology for greenhouse gas emission reduction by reducing energy consumption in construction, an industry that occupies 25% of the total energy consumption in South Korea. According to the experimental results of chemical reaction (i.e., acid reaction, sulfate resistance reaction and corrosion caused by sodium chloride) of fly ash-based geopolymer concrete, the theory and SEM analysis demonstrated that geopolymer concrete was acid resistant, sulfate resistant, and resistant to corrosion caused by sodium chloride. The basic properties were understood through qualitative analysis of a geopolymer concrete specimen using SEM, and through a study on the practical use of structure by verifying structural stability for geopolymer concrete, as part of development of technology. After future experiments and tests, the best geopolymer concrete ratio and curing method will provide a guideline.

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