No, 10 hours is not too long for a slow cooker. In fact, slow cookers are specifically designed to cook food over an extended period at low temperatures, typically ranging from 4 to 10 hours or more.
The purpose of a slow cooker is to allow for long, slow cooking times, which can help tenderize tough cuts of meat, develop rich flavors, and allow ingredients to meld together. Slow cookers operate at temperatures that are generally safe for cooking food over extended periods without posing significant risks.
However, it's important to follow the manufacturer's guidelines and specific recipes to ensure food safety and optimal results. Most slow cooker recipes provide recommended cooking times, which can vary based on the ingredients and desired outcome. Some recipes may require shorter cooking times, while others may benefit from longer cooking durations.
If you're unsure about the cooking time for a particular recipe or have concerns, it's best to consult the recipe instructions or refer to the manufacturer's guidelines for your specific slow cooker model. Additionally, ensuring that your slow cooker is in good working condition and properly maintained can help ensure safe and efficient cooking.