Reference for Pesachim 87:14

והאי משרת להכי הוא דאתא האי מיבעי ליה לכדתניא משרת

and eats it, it does not contain as much as an olive within the time of eating half [a loaf]. He raised all objection against him: If there are two [stew] pots, one of hullin and the other of terumah, and in front of them are two mortars, one containing [condiments of] hullin and the other containing terumah, and the latter fell into the former, they are permitted,<span class="x" onmousemove="('comment',' The pot of hullin is permitted to a lay Israelite.');">¹⁷</span> for I assume: the terumah fell into the terumah, and the hullin fell into the hullin. Now if you say that as much as an olive within the [time of] eating half [a loaf] is a Biblical [standard],why do we say, 'for I assume, the terumah' etc.<span class="x" onmousemove="('comment',' For of course it might have been the reverse; how then can we make this lenient assumption when there is a doubt of a Scriptural prohibition?');">¹⁸</span> ? - Leave the terumah of condiments alone, he replied, which is [only] Rabbinical.<span class="x" onmousemove="('comment',' By Scriptural law no terumah is required for these; hence the entire prohibition in this case is only Rabbinical.');">¹⁹</span> He raised an objection against him: [If there are] two baskets, one containing hullin and the other containing terumah, and in front of them are two se'ah [of provisions], one of hullin and the other of terumah and these fell into those, they are permitted, for I assume: the hullin fell into hullin, [and] the terumah fell into the terumah. Now if you say that as much as an olive within the eating of half [a loaf] is a Scriptural [standard], why do we say, 'because I assume' [etc.]?<span class="x" onmousemove="('comment',' V. n. 6.');">²⁰</span> - Leave the terumah [set aside] kutah there is as much as an olive of leaven, and for that he should be liable. at the present time<span class="x" onmousemove="('comment',' After the destruction of the Temple.');">²¹</span> he answered him, which is only Rabbinical. Now does this [law of] the infusion [of grapes] come for this purpose?<span class="x" onmousemove="('comment',' V. Supra ');">²²</span> It is required for what was taught: 'An infusion':

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