The aim of this study was to evaluate the potential use of fatty acids, triacylglycerols, and cholesterol in the detection of adulterated milk fat. The fatty acid, triacylglycerol, and cholesterol profiles of the mixtures of milk and non-milk fat (adulteration ratios of 10%, 30%, 50%, 70%, and 90%) were analyzed by gas chromatography. The results showed that concentrations of the fatty acids with oleic acid (C18:1n9c) and linoleic acid (C18:2n6c), triglycerides with C52 and C54, and cholesterol detected are proportional to the adulteration ratios remarkably. Oleic acid (C18:1n9c), linoleic acid (C18:2n6c), C52, and C54 were lower in pure milk fat than in adulterated mixtures. In contrast, pure milk has a higher cholesterol concentration than all adulterated mixtures (adulteration concentration in the range 10-90%). Thus, we suggest that oleic acid (C18:1n9c), linoleic acid (C18:2n6c), C52, C54, and cholesterol are suitable indicators and can be used as biomarkers to rapidly detect adulterated milk fat by gas chromatography. This study is expected to provide basic data for adulteration and material usage. Moreover, this new approach can detect the presence of foreign oils and fats in the milk fat of cheese and can find application in related studies.

Yogurt powder is fermented milk processed in the form of dry yogurt, and has advantages such as stability, storability, convenience, and portability. China and Vietnam are important export target countries because of the increased demand for dairy products. Therefore, we surveyed dairy product standardization in order to establish an export strategy. Lactic acid bacteria counts are unregulated in Korea and Vietnam. In China, lactic acid bacteria counts are regulated at 1×106 colony-forming units (CFU)/mL and detected at 6.24±0.33 Log CFU/mL. All three countries have regulated standards for total bacterial counts. In China, total bacterial counts of milk powder are regulated to n=5, c=2, m=50,000, M=200,000 and detected at 6.02±0.12 Log CFU/mL, exceeding the acceptable level. Lactic acid bacterial counts appeared to exceed total bacterial counts. Coliform group counts, Staphylococcus aureus, Listeria monocytogenes, and Salmonella species were not detected. Acidity is not regulated in Korea and Vietnam. In China, acidity was regulated to over 70°T and detected 352.38±10.24°T. pH is unregulated in all three countries. pH was compared to that of general fermented milk, which is 4.2, and that of the sample was 4.28±0.01. Aflatoxin levels are not regulated in Korea and China. In Vietnam, aflatoxin level is regulated at 0.05 ppb. Therefore, all ingredients of the yogurt powder met the safety standards. This data obtained in this study can be used as the basic data in assessing the export quality of yogurt powder.

This study of objective is to investigate the antioxidant properties of Godulbaegi kimchi by antioxidant activity, and evaluate the organic acid contents. An increase in antioxidant inhibitory effect was observed as the concentration of extraction solvent increased. The sample of methanol 80% extract showed higher DPPH radical scavenging activity. As the pH increased, the nitrite scavenging activity is decreased, and the sample diluted with methanol was the highest at 77.8% at pH 1.2. Total phenol content was the highest at 76.7 mg GAE/g when extracted from ethanol. The organic acids of Godulbaegi kimchi were detected malic acid, lactic acid and citric acid. As the storage period became longer, the total number of bacteria and lactic acid bacteria increased. It is suggested that Godulbaegi kimchi is very high in availability as a functional food and in its materials.