本研究以取自母牛分娩後第2、3、4 天分泌且等體積混合的乳汁作為材料，以阿拉伯膠、β-環狀糊精或幾丁聚醣之10% 水溶液，分別依1：4 體積比和牛初乳或乳清混合，以冷凍及噴霧乾燥法進行微膠囊化，並探討pH 值、熱處理及儲藏時間對微膠囊化初乳與乳清中IgG 安定性之影響。結果顯示，在酸鹼安定性方面，未微膠囊化之初乳在pH 7~8 有較高之IgG 活性，經微膠囊化者則以阿拉伯膠所得者在pH 7~8 時有較高之IgG 活性。在熱安定性方面，阿拉伯膠和β-環狀糊精對於初乳或乳清之IgG 均具有保護作用。在儲藏條件方面，儲藏溫度與包裝材質對於初乳或乳清之IgG 殘存活性有顯著影響，在4°C 儲存60 天後之IgG 活性較室溫高，以鋁袋包裝儲存者高於以透明塑膠袋包裝者，以阿拉伯膠微膠囊化之初乳在4°C 儲存60 天後之IgG 殘存活性顯著高於未微膠囊化者。

The bovine colostrums collected from the second, third, and fourth days postpartum were mixed with an equal volume and used as the raw materials. A 10% aqueous solution of gum arabic,β-cyclodextrin or chitosan was added in an equal volume of colostrums or microencapsulated through freeze-drying and spray-drying methods. The effects of pH, thermal processing, and storage conditions on the stability of the immunoglobulin G (IgG) in
microencapsulated colostrums and whey were investigated. Results showed that non-microencapsulated colostrums were found to have higher IgG activity at pH 7~8 than at other pH values. The microencapsulated colostrums with gum arabic were found to have higher IgG residual
activity at a pH 7~8. For thermal stability, gum arabic and β-cyclodextrin (β-CD) were found to have a protective effect on IgG activity of colostrums and whey. For storage conditions, storage
temperature and packaging materials were found to have a significant impact on residual IgG activity of colostrums and whey. After being stored for 60 days at 4 °C, the IgG activity was found to be higher than those stored at room temperature were. As for packaging materials,
aluminum bag-packed colostrums and whey were found to have higher IgG activity than transparent plastic bag-packed colostrums. After storage for 60 days at 4 °C, the microencapsulated colostrums with gum arabic were found to have significantly higher IgG residual activity than the non-microencapsulated colostrums.gwhey, andl,