Yes. In Jain Dharma, foods made by fermentation—like idli/dosa batter—are generally discouraged.

Why:

• Fermentation multiplies countless tiny living beings (nigodas, bacteria/yeasts). Heating or eating such food involves himsa (injury to life-forms).
• The batter is deliberately kept overnight to ferment, so it becomes “vasi” (not fresh). Many Jain codes for householders advise avoiding food kept overnight.

Tradition notes:

• Both Digambar and Shwetambar traditions traditionally discourage fermented items (yeast breads, idli/dosa batter, vinegars, alcohol, etc.).
• Practice among lay Jains can vary. Some families permit very limited, same‑day cultured items (like fresh curd) under specific household rules, but overnight‑fermented batters like idli/dosa are typically avoided—especially during periods of stricter observance (e.g., Paryushan, upvas, pachakkhan).

In short: dosa/idli are generally avoided in Jain practice because the required fermentation and overnight keeping involve avoidable himsa.