Lord Krsna was not angry at Putana for His own sake. Rather, He was angry because the Raksasi had killed so many small children in Vrajabhumi. Therefore He decided that she should be punished by having to forfeit her life

Expressions researched:
"Lord Kṛṣṇa was not angry at Pūtanā for His own sake. Rather, He was angry because the Rākṣasī had killed so many small children in Vrajabhūmi. Therefore He decided that she should be punished by having to forfeit her life"

Srimad-Bhagavatam

SB Canto 10.1 to 10.13

Lord Kṛṣṇa was not angry at Pūtanā for His own sake. Rather, He was angry because the Rākṣasī had killed so many small children in Vrajabhūmi. Therefore He decided that she should be punished by having to forfeit her life.

SB 10.6.10, Translation and Purport

On that very spot, the fiercely dangerous Rākṣasī took Kṛṣṇa on her lap and pushed her breast into His mouth. The nipple of her breast was smeared with a dangerous, immediately effective poison, but the Supreme Personality of Godhead, Kṛṣṇa, becoming very angry at her, took hold of her breast, squeezed it very hard with both hands, and sucked out both the poison and her life.

Lord Kṛṣṇa was not angry at Pūtanā for His own sake. Rather, He was angry because the Rākṣasī had killed so many small children in Vrajabhūmi. Therefore He decided that she should be punished by having to forfeit her life.