There are only a few references to Jews in the index.
Neutral
In Philosophy in the Tragic Age of the Greeks, Nietzsche mentions Jews in regards to how much the Greeks were able to learn from the Oriental lands. He mentions the Indians, Egyptians, Jews, and Chinese in this context.
Negative
In a public lecture "Socrates and Tragedy" from 1870, Nietzsche closes the lecture draft with this:
Most of the passage is crossed out and the next page torn out. But it is reconstructed from the Preliminary Draft, picking up from the end:In conclusion, a single question. Is music drama really dead, dead for all times? Should the Germani really be allowed to set beside that lost artwork of the past nothing other than "grand opera," as the ape appears besides Heracles? This is the most serious question of our art: and given the seriousness of this question, who as a Germani ----
The editors suggest that Cosima Wagner persuaded Nietzsche to remove this passage. She had written a letter to him asking him not to "name the Jews." He could also have removed it of his own accord.---- does not grasp that he has fallen prey to the Socratism of our day, which clearly can neither produce martyrs, nor speak the language of the "wisest of the Hellenes," which indeed not only boasts of knowing nothing, but in truth knows nothing. This Socratism is the contemporary [Jewish] press: I won't say another word.
In the afterword, the translators note that Nietzsche's references to Jews in his letters at this time increased markedly after he met Wagner, and "antisemitic references are found throughout the correspondence."
They state that Nietzsche's references to the "contemporary press" around this time could be a substitution for "Jewish press."
So at this early stage of his writing career, it seems that Nietzsche's anti-semitism was largely influenced by his association with Wagner, whose "Judaism in Music" had appeared in 1850 (under a pseudonym) and in 1869 under his own name.