Value-added applications of egg white proteins as functional food ingredients

蛋清因其特殊的发泡和胶凝特性而广泛应用于食品工业。传统的食品用途已经达到了瓶颈，并未能进一步提高鸡蛋行业的盈利能力。蛋清蛋白作为一种优质蛋白质来源，是公认的生物活性蛋白和生物活性肽的丰富来源；认识到鸡蛋是生物活性物质的天然储存库，为蛋清蛋白的增值利用打开了一扇新的窗口。卵黄转铁蛋白约占总蛋清蛋白的12%，是先天免疫的一个组成部分。使用成骨细胞（形成新骨），我们的初步研究表明，卵黄转铁蛋白提高成骨细胞的活性。本研究旨在研究卵转铁蛋白在破骨细胞和卵巢切除（OVX）大鼠模型中的结构和功能活性。去卵转铁蛋白的蛋清将用于制备水解物；本研究还旨在制备和表征新型卵巢转铁蛋白缺失蛋白水解物，并确定其对自发性高血压大鼠的降血压活性以及高脂肪诱导模型的胰岛素敏感性的有效性。鉴于骨质疏松症和高血压等代谢综合征的发病率不断上升，卵转铁蛋白和去卵转铁蛋白水解物作为功能性食品成分的增值应用的开发将为医疗保健支出的减少带来显著的公共效益，强化鸡蛋作为健康食品的积极形象。通过为快速发展的功能性食品和营养保健品行业开发增值成分，支持加拿大蛋品行业的可持续发展。

Egg white is used widely in the food industry for its exceptional foaming and gelling properties. Traditional food uses have reached its bottleneck and have failed to further enhance the profitability of the egg industry. As a high-quality protein source, egg white proteins are recognized as a rich source of bioactive proteins and bioactive peptides; knowing that egg is a natural reservoir of biologically active substances opens a new window for value-added utilization of egg white proteins.Ovotransferrin, accounting for about 12% of total egg white proteins, is a component of innate immunity. Using osteoblast cell (that forms new bone), our preliminary study showed that ovotransferrin improve the activity of osteoblast cell. The proposed work for ovotransferrin aims to study structure and functional activity of ovotransferrin in osteoclast cells and in an established ovariectomized (OVX) rat model. The ovotransferrin-depleted egg white will be used to prepare a hydrolysate; the proposed work also aims to prepare and characterize novel ovotransferrin-depleted egg white hydrolysate, and to establish its effectiveness on blood pressure lowering activity in spontaneously hypertensive rats as well as insulin sensitivity in a high-fat induced model. Giving the growing incidence of osteoporosis and metabolic syndrome including hypertension, the development of value-added applications of ovotransferrin and ovotransferrin-depleted egg white hydrolysate as functional food ingredients will result in significant public benefit for health care expenditure reduction, reinforce the positive image of egg as a healthy food, and support a sustainably growing Canadian egg industry at large by developing value-added ingredients for the rapidly expanding functional foods and nutraceuticals industry.