Reference for Menachot 5:2

כָּל הַמְּנָחוֹת נִלּוֹשׁוֹת בְּפוֹשְׁרִין, וּמְשַׁמְּרָן שֶׁלֹּא יַחֲמִיצוּ. וְאִם הֶחֱמִיצוּ שְׁיָרֶיהָ, עוֹבֵר בְּלֹא תַעֲשֶׂה, שֶׁנֶּאֱמַר (ויקרא ב), כָּל הַמִּנְחָה אֲשֶׁר תַּקְרִיבוּ לַה' לֹא תֵעָשֶׂה חָמֵץ. וְחַיָּבִים עַל לִישָׁתָהּ, וְעַל עֲרִיכָתָהּ, וְעַל אֲפִיָּתָהּ:

All grain offerings must be kneaded with lukewarm water. He must guard them lest they become leavened. If the remainder became leavened he has transgressed a negative commandment, for it is written, “No grain offering which you shall bring to the Lord shall be made leavened” (Leviticus 2:11). One is liable for the kneading, and for rolling and for baking [if he performed these after it became leavened].

Jastrow