Birkot HaTorah are comprised of three parts. In the first part, we bless Hashem who sanctified us with His mitzvot and commanded us to occupy ourselves with the study of Torah. In the second, we request that the Torah, which Hashem taught His nation Israel, be pleasant to us, that we merit learning it with desire, and that we and our offspring have the privilege of understanding the depth of its content.
In the third part, we bless and thank Hashem for choosing us from among all the nations and giving us His Torah. The Chachamim say (Berachot 11b) that this is the prime berachah of Birkot HaTorah, since it mentions the unique virtue of the nation of Israel, that Hashem “chose us from among all the nations” and, because of this Divine selection, consequently “gave us His Torah.” This is the nature of Israel’s soul, that it is attached and devoted to Hashem and His Torah, and therefore only the nation of Israel can receive the Torah and with it illuminate the world. Among the nations of the world, there may be righteous and devout gentiles, but this is a personal piety of individual people who lack the ability to repair the entire world. As seen from our long history, only the nation of Israel can serve Hashem within a national framework and strive to uplift and rectify the world in the path of truth and kindness.
Based on this, it is clear why the Ahavat Olam berachah (“Ahavah Rabbah,” according to Nusach Ashkenaz), which we say before the recital of Shema, can replace Birkot HaTorah. The main part of this prayer refers to Hashem’s love for Israel and its conclusion is, “Who chooses His people Israel with love.” Additionally, the subject of Torah is mentioned at length, for Israel and the Torah are inseparable.
In practice, one who is not certain as to whether he recited Birkot HaTorah can have kavanah to fulfill his obligation of Birkot HaTorah when reciting Ahavat Olam. Likewise, one who forgets to recite Birkot HaTorah before praying and arrives at Ahavat Olam should have in mind to fulfill his obligation of Birkot HaTorah when saying it, and after the prayer service remember to learn words of Torah as one does after Birkot HaTorah (Shulchan Aruch 47:7).