Table 4.

Most relevant words used by researchers in the field of citrus waste and animal feed production.

S/N	Author keywords (DE)	Occurrence	Keywords-plus (ID)	Occurrence
1	Citrus pulp	48	Citrus	290
2	Citrus	32	Fruit	104
3	Performance	23	Plant extracts	83
4	Pectin	22	Antioxidants	77
5	Antioxidant activity	20	Animals	74
6	Antioxidants	18	Citrus fruits	68
7	Citrus sinensis	18	Flavonoids	68
8	Sheep	17	Chemistry	57
9	Limonene	16	Metabolism	49
10	Citrus peel	14	Male	48
11	Silage	14	Citrus sinensis	41
12	Broiler	13	Unclassified drug	41
13	Citrus peels	13	Fermentation	37
14	Digestibility	13	Zea mays	34
15	Essential oil	13	Essential oil	31
16	Adsorption	11	Sweet orange	31
17	Fatty acids	11	Animalia	27
18	Growth performance	11	Adsorption	26
19	Response surface methodology	11	Cattle	26
20	By-product	10	Female	25