Java how to use for each loop in a 2 dimentional array list

Question

package package101;
import java.util.ArrayList;

public class TwoDimentionalArrayList {

    public static void main(String[] args) {
        
        ArrayList<String> bakeryList = new ArrayList();
        ArrayList<String> produceList = new ArrayList();
        ArrayList<String> drinkList = new ArrayList();
        ArrayList<ArrayList<String>> shoppingList = new ArrayList();
        
    
        bakeryList.add("sugar");
        bakeryList.add("flower");
        bakeryList.add("baking powder");
        
        produceList.add("lettuce");
        produceList.add("tomato");
        produceList.add("cucumber");
        produceList.add("potato");
        
        drinkList.add("pepsi");
        drinkList.add("coke");
        drinkList.add("orange juice");
        drinkList.add("coffee");
        drinkList.add("lemonade");
        
        shoppingList.add(bakeryList); 
        shoppingList.add(produceList);
        shoppingList.add(drinkList);
        
        // Method using two loops successful.
            
        for (int i = 0; i < shoppingList.size(); i++)
        {
            for (int j = 0; j < shoppingList.get(i).size(); j++)
            {
                System.out.println(shoppingList.get(i).get(j));
            } 
        }

        //Why I am not allowed to put String before t instead of Object?
                //Isn't each element in s of String type?

        
        for (ArrayList s : shoppingList){   
            for (Object t : s)
            {
                System.out.println(t);
            } 
        }                       
    }
}

//Method using 2 for loops successful. Method using 2 for each loops with String t : s failed. 
//Is there a simple way to make the second method work as well?