Is some ESR normal ?

[Hextejas]

Just for grins I measured the capacitance and ESR of an expensive new cap. 
It is a Nichikon, 100uf, 63v and the ESR is 0.48 ohms.
I guess that I expected it to be 0.00.
Was that unrealistic and is it normal that caps will have some ESR ?
I tried to read the datasheets but had no luck.

Thanks

[helius]

Expecting 0Ω ESR from any electrolytic cap is completely unrealistic. ESR from a healthy electrolytic cap will be on the order of 1Ω.

As I posted in another thread recently, you can compute the specified ESR from the Dissipation Factor using \$ ESR = {DF \over 2 \pi f C} \$
There is also a handy chart on the back of those cheap ESR meters that guides you to the value to expect.