Follow these steps

• Open the Google Spreadsheet file that your form responseas are saved into.
• Select the whole column, by clicking on the column name letter at the top of it - not just a set of rows in it.
• Apply the alignment you want.

Your selected alignment should now be applied to all new rows that are added to the Sheet from the Form.

(I have just tested this on one of my Forms, and seen that it works for the date-time value which is automatically put into the first column.)

Follow these steps

• Open the Google Spreadsheet file that your form responses are saved into.
• Select the whole column, by clicking on the column name letter at the top of it - not just a set of rows in it.
• Apply the alignment you want.

Your selected alignment should now be applied to all new rows that are added to the Sheet from the Form.

(I have just tested this on one of my Forms, and seen that it works for the date-time value which is automatically put into the first column.)