ABSTRACT
The global demand for high-quality protein sources in animal nutrition has led to increased research into sustainable and locally sourced feed ingredients. This study aimed to develop and characterize a feed resource utilizing sweet potato leaf protein concentrate (SPLPC) and tuber peels, two abundant and underutilized agricultural by-products. SPLPC was produced through the heat coagulation method, which involved extracting protein from fresh sweet potato leaves. Various feed grades were formulated by blending SPLPC and tuber peels at different ratios (0:100, 25:75, 50:50, 75:25, and 100:0). The proximate composition and mineral content of the feed grades were analyzed using standard analytical methods. The results showed that the dry matter content across all feed grades ranged from 89.88% to 90.81%, indicating similar moisture levels. Incorporating SPLPC into the feed grades significantly increased their crude protein content, ranging from 5.89% in 100% tuber peels to 39.84% in 100% SPLPC. This substantial increase in protein content is attributed to the high-quality protein present in SPLPC, which contains 50-70% protein on a dry weight basis. Conversely, the crude fiber content decreased from 4.827% in 100% tuber peels to 1.110% in 100% SPLPC, reflecting the lower fiber content in SPLPC compared to tuber peels. The ether extract (fat) content followed a similar trend, with the highest value observed in 100% SPLPC (9.930%) and the lowest in 100% tuber peels (4.280%), reflecting the presence of lipids in SPLPC. The nitrogen-free extract (NFE), representing soluble carbohydrates and readily digestible non-nitrogenous substances, was highest in 100% tuber peels (78.82%) and lowest in 100% SPLPC (43.29%), due to the high starch content in potato tubers and relatively low carbohydrate content in SPLPC. The mineral analysis revealed significant differences (p<0.05) across the feed grades for most minerals, including sodium, calcium, potassium, magnesium, iron, and manganese.
