국내산 초유의 가공방법에 따른 품질특성 연구

The characteristics of Holstein colostrum according to the methods that were employed in processing it were analyzed in this study to improve its industrial utilization. Colostrum samples were collected from the dairy farm of the National Institute of Animal Science (NIAS). The milk fat, protein, lactose, and SNF contents of colostrum were 4.34, 6.99, 3.37, and 11.10%, respectively. The effects of spray drying, freeze drying, freezing, acidification, and inoculation of lactic-acid bacteria on the characteristics of colostrum were then compared. The freezing of colostrum was found to be proper for long-term storage in a farm. Freeze-dried colostrum powder could not meet the processing requirements and the component standards for animal products in terms of the total bacterial and coliform bacteria counts, but spray-dried colostrum powder could meet the microbiological requirements because of its bactericidal effect during the spray-dry treatment. The inoculation of lactic-acid bacteria showed a better inhibitory effect on coliform than the acidification treatment, but protein precipitation appeared because of the low pH and the high acidity. To estimate the effects of the processing methods employed on the IgG of colostrum, the IgG contents of the milk treated by long temperature long time (LTLT) (65℃, 30 min), by inoculating the lactic acid bacteria starter, by spray drying, and by freeze drying were measured. The IgG contents of the colostrum were changed significantly by the processing treatment employed, from 53.98 mg/mLto 33.28, 34.82, 21.98, and 36.89 mg/mL, respectively.