Warm it

Try warming a bottle when you are in your car. Not an issue with WarmZe, a special air-activated wrap you place around a bottle that warms milk to the ideal temperature (90 to 104 degrees) in about 30 minutes. The WarmZe can be used multiple times throughout the day, up to 10 hours. Biodegradable.

warmze.com; about $16 for a starter set