探討迷迭香萃取物及乾冰之應用對於延長富含omega-3脂肪酸雞肉筋蛋白保存之可能性

Abstract

本研究擬針對先前開發之富含omega-3脂肪酸雞肉筋蛋白進行保存性試驗。由於omega-3 脂肪酸易於加工過程或貯藏期間因脂肪自氧化造成產品品質劣變。因此，本研究目的為藉由(1)迷迭香萃取物對於富含omega-3 脂肪酸油脂(亞麻籽油)之氧化安定能力及(2)迷迭香萃取物結合及乾冰之抗氧化柵欄技術之應用，以評估此方法對於延長富含omega-3 脂肪酸之雞肉筋蛋白保存之可能性。 首先，利用不同濃度之乙醇溶液及萃取時間確立迷迭香之最佳萃取條件。結果顯示以80%乙醇溶液使用超音波萃取(50°C)30分鐘而得之迷迭香萃取物不僅具較理想之多酚組成、含量及較佳(p<0.05)之體外抗氧化能力外，於加速氧化試驗(Schaal oven test, 60°C)中亦可提升亞麻籽油之氧化安定性，且其效果優於(p<0.05)生育醇及2,6-二第三丁基對甲酚。進一步將80%迷迭香乙醇萃取物(RE)與乾冰(DI)結合應用於富含omega-3 脂肪酸雞肉筋蛋白之貯藏試驗。以外觀而言，添加DI有助於提升產品之白色度及硬度(p<0.05)。添加RE則使產品具較高(p<0.05)之omega-3及omega-6脂肪酸保留量。此外，於14天4°C貯藏試驗中，結合RE及DI添加之組別其初級氧化產物量最低(p<0.05)且添加RE可有效延緩(p<0.05)次級氧化產物之生成。再者，結合RE及DI添加亦能提升產品之保水力(p<0.05)。於60天-20°C貯藏試驗中亦得相似之結果:無論單一或結合添加RE及DI皆可減少(p<0.05)脂質氧化產物之生成;然而，於蛋白質降解而言，各處理組間並無顯著之差異(p>0.05)。 綜觀上述，將80%迷迭香乙醇萃取物結合乾冰使用可有效延緩產品於加工及低溫貯藏中脂質氧化之情形，此外亦提供產品較理想之外觀、質地及脂肪酸組成。此抗氧化技術將有潛力應用於延長富含omega-3 脂肪酸產品之保存。

In our previous study, an omega-3 fatty acid (flaxseed oil) fortified chicken surimi was developed from spent hen breast protein. However, omega-3 fatty acids are prone to autoxidation during processing or storage, leading to quality deterioration. Therefore, in this study we aimed to investigate (1) oxidative stability of flaxseed oil with the addition of rosemary extract, and (2) potential effects of hurdle technology concept [rosemary extract and dry ice (DI)] on shelf life prolongation of chicken surimi fortified with flaxseed oil. The optimal extraction condition of rosemary leaves was first determined, and 80% ethanolic extract of rosemary from 30-min ultrasonic extraction (abbreviated as RE) possessed better (p<0.05) in vitro antioxidant abilities and effectively retarded lipid oxidation of flaxseed oil under Schaal oven test condition (60°C) compared to α-tocopherol or BHT. Further application of RE and DI on chicken surimi fortified with flaxseed oil was evaluated. DI addition increased (p<0.05) whiteness values and hardness of products. Meanwhile, ω-3 and ω-6 fatty acids were greatly preserved in products with the addition of RE. During a 14-day storage at 4°C, products with the combined usage of RE and DI had the lowest (p<0.05) primary oxidative substances, while RE exerted a better (p<0.05) ability to inhibit the formation of malondialdehyde. Regarding protein degradation, the combined usage of RE and DI decreased (p<0.05) the centrifugation loss of products. In addition, a single or combined usage of RE and/or DI decreased (p<0.05) oxidative substances in products after 60 days of -20°C storage. However, no (p>0.05) differences among treatments were observed on protein degradation. In conclusion, the hurdle technology concept of RE and DI successfully retarded lipid oxidation upon chilled and frozen storages and provided more desirable appearance, texture, and fatty acid profiles of chicken surimi fortified with flaxseed oil. The technique might be a prospective method to prolong the shelf life of products rich in ω-3 fatty acids.