When it comes to food safety, it's important to follow proper guidelines to avoid the risk of foodborne illnesses. Leaving homemade beef stew out of the fridge overnight and half the day can potentially lead to bacterial growth and spoilage. Here's what you need to know:

1. The Two-Hour Rule: According to food safety guidelines, cooked food should not be left in the temperature danger zone (between 40°F/4°C and 140°F/60°C) for more than two hours [1]. This includes the time the stew is left out at room temperature.

2. Bacterial Growth: Bacteria can multiply rapidly in the temperature danger zone, increasing the risk of foodborne illnesses. Leaving the stew out for an extended period allows bacteria to grow to unsafe levels.

3. Signs of Spoilage: Even if the stew looks and smells fine, it's important to note that harmful bacteria may not always produce noticeable signs of spoilage. Therefore, relying solely on sensory cues may not be sufficient to determine if the stew is safe to consume.

Based on the information available, it is recommended to discard the homemade beef stew if it has been left out of the fridge overnight and half the day. Consuming food that has been left out for an extended period can pose a risk to your health.

Learn more:

1. How Long Can Cooked Foods Be Left Out of the Refrigerator ...
2. Help! Left Beef Stew in kitchen overnight - should we eat it? | Mumsnet
3. Beef stew was left cooling on the stove for like six hours - Seasoned Advice