Commentary for Avodah Zarah 112:1

There are two resolutions to this difficulty. First of all, it may be that the entire comparison between tithes and yayin nesekh is unjustified. The rabbis were strict when it came to yayin nesekh—the liquid is subject to becoming yayin nesekh as soon as it goes down into the vat, even before it is skimmed. The dispute was only with regard to tithes.
But Rava did use a baraita about tithes in his understanding of the mishnah. Therefore, he must posit that there are indeed three opinions.