No abstract

To elucidate the relationship between shyandan yolk formation and NaCl penetration degree, fresh duck eggs were brined in 26% NaCl and a prolonged brining test was conducted for up to 24 weeks. Shyandan yolk was obtained from brine-cured duck shell eggs in 26% NaCl for 4-6 weeks and subsequently heated at 85 degrees C for 90 min. Though NaCl contents for albumen and yolk increased to 14.8 and 8.9%, respectively, during the prolonged test for up to 24 weeks, the R values (NaCl/water x 100) were similar (increased from 0.6 to 21) throughout the brining process. The oil-off ratio of the yolk increased rapidly from 14 to 50% (0-6 weeks) and gradually decreased during the extended brining. Granulation and gelation of yolk appeared in the different stages of the brining process. This study demonstrates that the formation of shyandan yolk was determined by the degree of NaCl penetration.

Numerous attempts have been made to develop angiotensin I converting enzyme (ACE) inhibitors from various sources of food protein. Generally chicken leg bones are discarded after industrial chicken meat processing without any substantial benefit. In previous studies, chicken leg bone proteins were hydrolyzed by various enzymes and the results demonstrated that Alcalase hydrolysates have considerable ACE inhibiting activities. In this study, the best ACE inhibitory hydrolysate (A4) (which was derived from chicken leg bone protein by Alcalase after 4 h incubation) was orally administrated (50 mg/kg bw) in spontaneously hypertensive rats (SHRs) to investigate its antihypertensive effects. After oral administration of A4, a maximal reduction activity of about 26 mmHg was found at 4 h and maintained to 8 h. Moreover, SHRs treated with A4 (50 mg/kg bw/day) for eight weeks exhibited a reduction in systolic blood pressure, which is as significant as the effects of Captopril (P < 0.05). These results suggested that chicken leg bones have a high potential for utilization to develop ACE inhibitors as potential food ingredients intended to alleviate hypertension.