Alternating dietary fat sources for growing-finishing pigs fed dried distillers grains with solubles: II. Fresh belly and bacon quality characteristics.

Crossbred pigs (n = 216) were used to test the effects of phase-feeding beef tallow (BT) and yellow grease (YGr) on fresh belly and bacon quality characteristics of growing-finishing swine fed dried distillers grains with solubles (DDGS). Pigs were blocked by initial BW (26.0 ± 5.3 kg) before allotment to pens (6 pigs/pen), and pens (6 pens/block) were assigned randomly to 1 of 6 dietary treatments: 1) corn-soybean meal-based grower and finisher diets formulated with 4.7% YGr fed during all 5 feeding phases (YG15); 2) corn-soybean meal-based diets formulated with 5.0% BT fed during all 5 phases (BT15); 3) diets containing 5.0% BT fed during the first 2 phases and diets with 4.7% YGr fed the last 3 phases (YG345); 4) diets formulated with 5.0% BT fed during first 3 phases and diets containing 4.7% YGr fed during the last 2 phases (YG45); 5) diets containing 4.7% YGr fed during the first 3 phases and diets with 5.0% BT fed during the last 2 feeding phases (BT45); or 6) diets formulated with 4.7% YGr fed during the first 2 phases and diets with 5.0% BT fed during the last 3 phases (BT345). All dietary treatments were formulated with 30% dried distillers grains with solubles (DDGS) during the first 3 phases, 15% DDGS in the fourth phase, and no DDGS during the last phase. Fresh belly quality data were collected on the left-side bellies, whereas bacon from the right-side bellies was prepared under commercial processing conditions. Additionally, USDA-certified No. 1 slices were collected for cooking characteristics and sensory panel evaluations. Bellies from the YG15-fed pigs were softer (P ≤ 0.05) than bellies from BT15-fed pigs; however, instrumentally measured belly firmness was not (P ≥ 0.06) different among treatments. Concentrations of palmitic, stearic, and oleic acids, as well as all SFA and all MUFA, were greater (P < 0.01) in bellies from BT15- than YG15-fed pigs. In contrast, proportions of linoleic acid, all PUFA, and iodine value were greater (P < 0.01) in belly fat from YG15-fed pigs in comparison with BT15-fed pigs. Yield of commercially processed bacon (P ≥ 0.06), mechanical bacon tenderness (P ≥ 0.69), and bacon palatability attributes (P ≥ 0.55) were not affected by the dietary treatments. Thus, results of this study indicated that phase-feeding BT to pigs fed diets formulated with DDGS produced minor improvements in fresh belly firmness due to greater proportions of SFA but had no effect on yields of commercially processed bacon or bacon quality characteristics.