| Abstract: | 本實驗研究肉品之最終中心溫度（65, 67, 69, 71及73℃）對醃漬（添加1.6, 2.0及2.4 % 氯化鈉或0.012, 0.018及0.024 % 亞硝酸鈉）及未醃漬（控制組）豬里肌肉、豬後腿肉及鴨胸肉所含酵素及水溶性蛋白質比率值（water-extractable biuret-positive proteins ratio, EBPR）之影響。結果顯示，加熱過豬里肌肉、豬後腿肉及鴨胸肉之酸性磷酸酯酉每（acid phosphatase）、丙酮酸激酉每（pyruvate kinase）及乳酸脫氫酉每（lactate dehydrogenase）活性皆比未加熱組低（p<0.05）。當豬里肌肉（控制組及添加氯化鈉或亞硝酸鈉組）酸性磷酸酯酉每活性降至8.47 U / kg以下時可推測豬肉製品之最終中心溫度至少已達67℃。當鴨胸肉（控制組及添加氯化鈉或亞硝酸鈉組）酸性磷酸酯酉每活性降至29.47 U / kg以下時，可推測鴨肉製品之最終中心溫度至少已達69℃。當豬里肌肉（控制組及添加氯化鈉或亞硝酸鈉組）丙酮酸激酉每活性降至31.09 U / kg以下時可推測其最終中心溫度至少已達67℃。當鴨胸肉（控制組及添加氯化鈉或亞硝酸鈉組）丙酮酸激 酉每活性降至14.23 U / kg以下時，可推測鴨肉製品之最終中心溫度至少已達69℃。當豬里肌肉（控制組及添加氯化鈉或亞硝酸鈉組）乳酸脫氫酉每活性降至249.4 U / kg以下時可推測其最終中心溫度已達71℃。當鴨胸肉（控制組及添加氯化鈉或亞硝酸鈉組）乳酸脫氫酉每活性降至208.98 U / kg以下時，可推測鴨肉製品之最終中心溫度已達73℃。當豬里肌肉及鴨胸肉（控制組及添加氯化鈉或亞硝酸鈉組）之水溶性蛋白質比率值小於1.13時可推測豬肉製品之最終中心溫度至少已達69℃。豬後腿肉之酸性磷酸酯酉每、丙酮酸激酉每、乳酸脫氫 酉每活性及水溶性蛋白質比率值與豬里肌肉相似。 分析醃漬及未醃漬對豬里肌肉、豬後腿肉及鴨胸肉化學特性之影響，發現氯化鈉或亞硝酸鈉的添加，可顯著降低豬里肌肉、豬後腿肉及鴨肉中酸性磷酸酯酉每及丙酮酸激酉每之活性（p<0.05）；亞硝酸鈉或2.0 %以上的氯化鈉的添加，可顯著降低鴨肉中乳酸脫氫酉每之活性（p<0.05），但氯化鈉或亞硝酸鈉的添加，對豬里肌肉及豬後腿肉中乳酸脫氫酉每之活性無顯著影響（p>0.05）但對水溶性蛋白質比率值有顯著下降的趨勢（p<0.05）。
The purpose of this study was to study the effect of internal temperature (65, 67, 69, 71 and 73℃), sodium chloride (1.6, 2.0 and 2.4%) or sodium nitrite (0.012, 0.018, 0.024%) on enzymatic activies of pork loin, pork ham and duck breast. The activities of pyruvate kinase, acid phosphase and lactate dehydrogenase in the heated treatments were lower than those in the unheated treatment. When acid phosphatase activity of pork loin were decreased to 8.47 U / kg, it indicated that internal temperature of pork products reached to 67℃. When acid phosphatase activity of duck breast decreased to 29.47 U / kg, it indicated that internal temperature of duck products reached to 69℃. When pyruvate kinase activity of pork loin decreased to 31.09 U / kg, it indicated that internal temperature of pork products reached to 67℃. When pyruvate kinase activity of duck breast decreased to 14.23 U / kg, it indicated that internal temperature of duck products reached to 69℃. When lactate dehydrogenase activity of pork loin decreased to 249.4 U / kg, it indicated that internal temperature of pork products reached to 71℃. When lactate dehydrogenase activity of duck breast decreased to 208.98 U / kg, it indicated that internal temperature of duck products reached to 73℃. When water soluble biuret-positive proteins ratio (EBPR) of pork loin and duck breast decreased to 1.13, it indicated that internal temperature of pork products reached to 69℃. The effects of curing and uncuring of meat on the chemical characteristics of pork loin, pork ham and duck breast were studied. With sodium chloride (1.6, 2.0 and 2.4%) and sodium nitrite (0.012, 0.018, 0.024%), the activities of pyruvate kinase, acid phosphatase and lactate dehydrogenase in pork loin, pork ham and duck breast were significantly decreased (p<0.05). With sodium nitrite (0.012, 0.018, 0.024%) and sodium chloride (2.0 and 2.4%), the activity of lactate dehydrogenase in duck breast significantly decreased（p<0.05）; however, the activities of lactate dehydrogenase decreased in pork loin and pork ham significantly decrease affecting by sodium chloride and sodium nitrite. With sodium chloride and sodium nitrite, EBPR in pork loin and pork ham significantly decreased（p<0.05）. |
