Antioxidant Activity Of Procine Bone Protein Hydrolysates And Application Of Bone Protein Hydrolysates

Bone is a byproduct in meat processing,and occupy 10～15%of naked body,bone contained rich protein,fatty acid,phospholipids and phosphoprotein,the compounds promoted growth of cerebral nerves and intelligence capacity.Bone had 11%～15%protein.Bone protein contained rich amino acid,and bone protein was a structural protein,it was the most rich protein in animal body,occupied 25%～30%in whole protein of animal body.Collagen was generally used by hydrolyzed for enzyme,hydrolysates of bone protein cantained polypeptide and amino acid, hydrolysates of bone protein were facilible to digest and absorb by human body,it had distinct nutrition efficacy.At the same time it enhanced its functional property,and it possessed antioxidant activity.The optimum hydrolyzing condition of bone protein and antioxidant activity of bone protein hydrolysates in a liposome system were studied in this paper.Bone protein was hydrolyzed by alcalase or dispase or trypsin,and was hydrolyzed by different substrate concentration and[E]/[S]. Degree of hydrolysis was determined using pH-Stat method.Hydrolysates was used and researched inhibition of peroxide formation in a liposome-oxidizing system.Hydrolyzing condition was chosen by DH and TBARS value.The result of optimization of hydrolyzing condition of bone protein:bone protein was hydrolyzed for 5h by alcalase,substrate concentration for 7%and[E]/[S] for 1:100.Antioxidant activity of bone protein hydrolysates in a liposome system and the possible mode of action was studied in this paper.Bone protein was hydrolysis for 0.5-6h by alcalase,the degree of hydrolysis was determined by pH-Stat method.Hydrolysates was used to inhibition of TBARS (Thiobarbituric acid-reacitive substances) in a liposome-oxidizing system.Reducing power, metal-Chelating activity and radical-scavenging activity were determined.The result showed that 7%bone protein hydrolysates for 5h by alcalase have best antioxidant activity.Bone protein hydrolysates possessed strong Cu²⁺-and Fe²⁺-chelation ability and marked reducing power,both of which were accentuated with hydrolysis time.The protein hydrolysates also showed strong radical-scavenging ability.The antioxidant activity of alcalase-hydrolyzed bone protein at some specific low concentrations was close or comparable to that of PG.Although intact bone protein displayed an antioxidative effect,it was far less potent than hydrolyzed bone protein.The results demonstrated that enzyme-hydrolyzed bone protein can act as a metal ion chelator,a hydrogen donor,as well as a radical stabilizer to inhibit lipid oxidation.In order to improve the functional properties of bone protein and extend its application in food industry,bone protein was hydrolyzed by alcalase for different times.Degree of hydrolysis was determined using pH-Stat method,and water-holding capacity,oil-holding capacity,emulsification, foaming and foaming stability of bone protein hydrolysates were determined,.The results showed that the oil-holding capacity,emulsification and foaming activity of bone protein hydrolysates increased gradually with the increase of degree of hydrolysis,especially for 3h hydrolysates. However emulsification stability and foaming stability of the hydrolysates reduced at a certain extent.Pork patties contained 1.5%NaCl and hydrolyzed bone protein(bone protein hydrolysis,5h with alcalase) with different concentration and 0.02%BHA(butylated hydroxyanisole,BHA).Lipid oxidation in patties during storage was analyzed by measuring the TBARS and protein carbonyl content.Bone protein hydrolysis possessed antioxidant activity,and stronger antioxidant activity by increased hydrolysis concentration,sensory evaluation indicated that bone protein hydrolysis was added in pork patties improved the color,tissue structure and decreased lipid oxidation flavor. Especially pork patties with hydrolyzed bone protein of concentration 2%possessed higher antioxidant activity and better sensory evaluation value.