Possible Clues:

• Dresden "Drat!"
• Hamburger's beef?
• Austrian’s exclamation
• Rhineland rats?
• “Oh!” from Ohm
• Herr's "Alas!"
• German exclamation hidden in 'pita chips'
• German 'Alas!'
• Austrian exclamation
• "___ Tannenbaum" (16th-century folk song that inspired a carol)