Rashi on Numbers 28:31/רש"י על במדבר כ״ח:ל״א

1תמימים יהיו לכם ונסכיהם THEY SHALL BE TO YOU WITHOUT BLEMISH, AND THEIR DRINK OFFERINGS — i.e. the drink offerings, too, shall be without blemish. Our Rabbis learned from this that wine upon which mold shows itself is unfit for drink-offerings (Menachot 87a).