For an ice cream factory, if demand rose 100% in one week, which production methodology is likely to be best to deal with the rise in demand?

To deal with a sudden 100% rise in demand in an ice cream factory, the most suitable production methodology would likely be Just-in-Time (JIT) production. Here's why:

1. Assess the Current Situation: The first step is to understand the current production capacity and inventory levels. If the factory is already producing at maximum capacity, it will need to find ways to increase production. If there is excess inventory, it can be used to meet some of the increased demand.

2. Implement Just-in-Time (JIT) Production: JIT is a production methodology that aims to improve a business's return on investment by reducing in-process inventory and associated carrying costs. In the context of the ice cream factory, this means producing ice cream just in time to meet demand, rather than producing large quantities in advance. This can help to manage the sudden increase in demand.

3. Increase Efficiency: The factory should look for ways to increase efficiency in the production process. This could involve streamlining operations, investing in more efficient machinery, or training staff to work more effectively.

4. Work with Suppliers: The factory will need to work closely with its suppliers to ensure it can get the necessary ingredients in time to increase production. This might involve negotiating faster delivery times or larger deliveries.

5. Monitor and Adjust: Finally, the factory should closely monitor demand and adjust its production levels as necessary. If demand continues to increase, it may need to further increase production. If demand drops, it should avoid overproduction by quickly reducing production levels.

Remember, while JIT can be very effective, it also requires a strong relationship with suppliers and a keen understanding of customer demand patterns. It may not be suitable for all businesses.