The Application And Research Of Tea Polyphenols In Dog Food

The main purpose of this paper is to develop and research a kind of high qualityfunctional dog food, tea polyphenols (TP) was used as a functional additive to reduce the fatoxidation of dog food and make it more advantages on the storage, and improve theantioxidant properties and the intestinal health of dogs.Using the TP retention rate as the index, optimized the addition and adding mode of TP inthe dog food. The results showed that the retention rate was higher by adding TP in rawmaterials of the dog food before processing. The addition do not affect retention rate ofTP; Optimized the TP addition by the physics properties and palatability of the dog food, theresults showed that the TP had a little effects on color; It has no effect on floating rate andvolume weight; But has a certain influence on the smell of the dog food, there was a little teaflavour when addition was0.5%, was more tea and bitter flavour hen addition was1%.Palatability experimental results showed that the TP at a concentration of0.5%has a bettereffect on the palatability and preference of dogs; when adding amount was1%, TPsignificantly affected the palatability, reduced the feed intake.Therefore, the suitable amountof TP was0.5%. The results of storage experiment showed that, during the period of storage,the retention rate of TP was about82%, essentially unchanged which has a great advantage inpersisted.The peroxide value (POV) and malondialdehyde (MDA) content of different dog foodadded TP or contrast antioxidant-Butylated hydroxytoluene（BHT） and tocopherol wereresearched to prove the antioxidation of the dog food added TP. Results indicated that at25oC,the POV value and MDA content were significantly decreased by added TP in the dogfood, the fat oxidation degree significantly reduced, and the oxidation degree of the dog foodcoating oil after the extrusion was lower, the POV value of the group added0.5%TP wassignificantly reduced by10.78%, the content of MDA was significantly reduced by14.44%,means that0.5%supplement of TP had a better antioxidant effect; The antioxidant effects ofTP and BHT were similar under the same addition, proved that add0.5%TP can reduce thedegree of oxidation of high fat dog food, and the way of coating oil after extrusion oxidationdegree was better. scavenging activities on DPPH·of dog food added TP were researched, theresults further showed that the supplement of0.5%TP in the dog food can improve theclearance rate on DPPH·, and the way of coating oil after extrusion oxidation degree wasbetter.Through the bacteriostatic circle experiment investigates the effect of TP and the dogfood added TP on several common pathogenic bacteria inhibition. The experimental resultsshowed that TP has inhibitory effect on Escherichia coli, Staphylococcus aureus, has noinhibition on Lactobacillus; the dog food added0.5%TP has a better inhibitory effect onEscherichia coli, Staphylococcus aureus.The antioxidant and the antibacterial activity effect of the dog food added TP wereverified through animal feeding trial. The test results of serum index showed that the dogfood added0.5%TP significantly increased the activity of SOD and GSH-px in serum and total antioxidant capacity by7.72%、4.64%and19.86%respectively at the end of theexperiment, reduced the MDA content significantly than control group by15.09%; Prove thatadding0.5%TP in dog food can make the antioxidant properties of dogs better. The testresults of intestinal index showed that0.5%TP has inhibitory effect on intestinal pathogenicbacteria, feeding the dog food contained TP can improve the intestinal health of dogs in theexperimental period.