Hello and Good Afternoon,
Thank you for asking this question.
As it pertains to a small taste of wine .... my suggestion would be to ask for small glass or wine ('un bicchierino di vino'). This would be like asking for a shot of win, but you can always substitute the word 'vino' for another drink. BTW ... The word 'spudatza' is probably a dialect from the native town where your relatives grew up.
If you have any additional questions please feel free to send me a message.
Grazie e buona giornata!!