Quality Parameters of Pet Treats Generated from Beef Processing Co-products

Abstract By-products such as beef liver (BL) and beef heart (BH), while rich in protein, vitamins, and minerals, can be difficult products for incorporation into mixtures. Sodium alginate (SA) and calcium lactate (CL) can be used to improve structure of protein sources. The objective was to determine the quality of restructured BL and BH pet treats using ALGIN as a structure forming agent. Quality parameters assessed were pH, expressible moisture, cooking loss, and water activity of raw and dehydrated pet treats. After grinding, BL and BH, were mixed: 25%BL:75%BH, 50%BL:50%BH, and 75%BL:25%BH. The 3 BL:BH combinations were mixed with 2 dosages of ALGIN (0.5% SA + 0.425% CL, and 1% SA + 0.85% CL) to produce 6 treatments. Each treatment was then extruded into 20-mm-thick jerky slices and refrigerated at 3°C for 48 h. Samples were dehydrated at 93°C for 2.5 h for cooking loss analysis. Ten raw samples (25.4 mm × 25.4 mm) were used to measure expressible moisture, and another ten raw samples were used to measure pH. Water activity was assessed on ten raw and ten dehydrated samples. Data were analyzed with the GLIMMIX procedure of SAS and means were separated at P ≤ 0.05. Cooking loss decreased as ALGIN dosage increased in all BL and BH mixtures (P < 0.0001); however, cooking loss percentage increased as BH proportions increased (P = 0.0001). Water activity of dehydrated samples decreased as BL proportions increased (P < 0.0001), but with increasing ALGIN dosage, water activity of dehydrated treats increased (P = 0.0193). Raw pH was not affected by treatment. Expressible moisture of samples increased with increasing BL proportions (P < 0.0001) but decreased as ALGIN dosage decreased (P < 0.0001). Use of ALGIN allowed for BL and BH to be restructured into an acceptable form for use in pet treats.