In Jainism, the principle of non-violence (ahimsa) is the highest duty. Killing or eating a living being creates karmic bondage. So, in a situation where you face a choice between harming a life and allowing great harm to your family, the act of killing would normally bind negative karma.

Key points to consider:

• Intention matters. If you truly have no reasonable alternative and your intention is to preserve life without relish or harm, the karmic impact is viewed differently than if you choose violence with anger or thrill.
• Remorse and atonement help. After such a situation, sincere pratikraman (confession and repentance), vows of non-violence, and resolve to avoid harm in the future are important in reducing karmic burden.
• Practical guidance from Jain teachers emphasizes seeking any possible non-violent alternative first (e.g., saving lives without killing, or relying on other measures). If no alternative exists, the emphasis remains on minimizing harm and maintaining a pure inner resolve.

In short: eating steak in a life-or-death emergency would create negative karma, but the exact magnitude depends on your intention, remorse, and subsequent commitment to ahimsa. Afterward, engage in prayerful reflection and pratikraman to purify the mind and lessen ongoing karma.