import re
rx = r"\(E\d+\)|([^\W\d]+(?:\s+[^\W\d]+)*)"
s = "Pork and beef, water, salt (1,7%), spices (white pepper, nutmeg, coriander, cardamom), stabilizer (E450), glucose, antioxidant (E316), a preservative (E250), flavorings"
res = [x for x in re.findall(rx, s) if x]
print(res)