import re
Ingredient = 'Beef stock (beef bones, water, onion, carrot, beef meat, parsnip, thyme, parsley, clove, black pepper, bay leaf), low lactose cream (28%), onion, mustard, modified maize starch,tomato puree, modified potato starch, butter sugar, salt (0,8%), burnt sugar, blackcurrant, peppercorns (black, pink, green, all spice, white) 0,4%.'
res = re.sub(r'\s*\([^()]*\)[^,]*(?:,\b[^,]*)*', "", Ingredient)
print(re.split(r',\s*', res))
 
vals = re.findall(r'\([^()]*\)|([^\W\d]+(?:\s+[^\W\d]+)*)', Ingredient)
vals = [x for x in vals if x]
print(vals)

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