Besides reading minds, how did Sai Baba demonstrate his power over the physical world in the story of Boss Dharamsee and the grapes?

In the account from Chapter 35, Sai Baba demonstrated a profound mastery over the physical world. When the skeptical Boss Dharamsee was given grapes with seeds, he was reluctant to eat them. However, upon Baba's command, "Throw them in and eat," Dharamsee obeyed. The physical properties of the fruit changed at that very moment. The grapes, which were part of a batch that others like Tarkhad confirmed had seeds, became completely seedless for Dharamsee. This act shows Baba's ability to alter the very nature of a physical object to facilitate a spiritual lesson, proving, as Dharamsee thought, "What is impossible for these saints?"