Table 3. Change of nitrogen content extracted from hide.

Hide storage duration, days	Amount (g/kg of hide) of nitrogen extracted from hide
	not preserved	vacuumed	salted
3	4.14	3.45	3.07
13	4.56	3.82	3.23
16	4.65	3.40	3.26
20	5.48	4.07	3.88
21	7.06	4.24	4.12