Does homemade soap go bad?..
The short answer. NO
Soap does not expire or go bad it can be used indefinitely. In fact, soap gets better with age. The longer it sits the harder it gets. It becomes more mild. Do not let anyone tell you that fresh soap is better. This is false.
The first issue that may arise is the oils in the soap going rancid, which can cause dreaded orange spots (DOS) on the soap’s surface. These spots are blemishes that can range in color from yellow to orange to brown and can appear in small isolated dots or can cover the entire soap. Despite the unsightly appearance, soap affected by DOS is still safe to use. If the oil has gone rancid you may get a stale odor. The second is the fragrance used in the soap causing the discoloration. In this case, fragrance is not being mixed in thoroughly. This may give the appearance of dreaded orange spots but it is purely cosmetic.