Replacing animal fat with tiger nut ( Cyperus esculentus ) flour: Effect on quality characteristics of refrigerated beef burger

The impact of replacing animal fat with tiger nut ( Cyperus esculentus ) flour (TNF) on the bioactivity and quality attributes of beef burgers was evaluated during refrigerated storage for 6 days. The control formulation consisted of 85% meat and 15% animal fat. The animal fat part was replaced with TNF at levels of 0%TNF (T1), 5%TNF (T2), 10%TNF (T3), and 15%TNF (T4). In addition to enhancing dietary fiber content, incorporation of TNF significantly ( P -value ≤.05) increased total phenolic content and antioxidant activity, as determined by the Folin–Ciocalteu and DPPH (2,2-diphenyl-1-picrylhydrazyl) assays respectively. Lipid oxidation was markedly reduced in TNF-treated samples during storage, as reflected by lower peroxide and thiobarbituric acid reactive substances (TBARS) values. After 6 days, T4 exhibited the lowest peroxide value (2.60 meq O 2 /kg fat) and TBARS value (0.47 mg MDA/kg fat) compared with the control T1 (4.88 meq O 2 /kg fat and 0.94 mg MDA/kg fat, respectively). Microbiological analysis indicated improved microbial quality in burgers containing TNF. Texture profile analysis showed that firmness, cohesiveness, gumminess, chewiness, and springiness of produced beef burgers increased with TNF addition. Moreover, TNF reduced cooking loss by 25%, from 42% in T1 to 17.34% in T4. Sensory evaluation revealed that sample T2 was the most preferred formulation.