In plain words
Foods that are excessively bitter, sour, salty, hot, pungent, dry, and burning are dear to the rājasa and bring pain, grief, and illness.
Word for word
[Very] bitter, sour, salty, hot, sharp, dry and burning foods are desired by the rājasa, giving pain, grief and disease.
कट्वम्ललवणात्युष्णतीक्ष्णरूक्षविदाहिनःआहारा राजसस्येष्टा दुःखशोकामयप्रदाः
Other commentaries
The commentators
▸Bhagavadgītābhāṣyam· bhāṣya
कट्वम्ललवणात्युष्णतीक्ष्णरूक्षविदाहिनः इत्यत्र अतिशब्दः कट्वादिषु सर्वत्र योज्यः, अतिकटुः अतितीक्ष्णः इत्येवम् । कटुश्च अम्लश्च लवणश्च अत्युष्णश्च तीक्ष्णश्च रूक्षश्च विदाही च ते आहाराः राजसस्य इष्टाः, दुःखशोकामयप्रदाः दुःखं च शोकं च आमयं च प्रयच्छन्तीति दुःखशोकामयप्रदाः ॥ ९ ॥
In plain words
'Bitter, sour, salty, scorching, sharp, dry, burning' -- and here, that word 'excessively' needs to be read into every single one of these, not just the first: excessively bitter, excessively sharp, and so on down the list. Bitter, sour, salty, scorching, sharp, dry, burning -- foods like that are exactly what a rajasic person craves, and they are 'producers of pain, grief, and disease' -- meaning simply that they bring on pain, and grief, and disease, and that is why they are called that.
Close to the Sanskrit
'Bitter, sour, salty, very hot, pungent, dry, burning' -- here, the word 'ati' (excessive) is to be connected everywhere among the items beginning with 'bitter,' thus: 'excessively bitter,' 'excessively pungent,' and so on. Bitter, and sour, and salty, and very hot, and pungent, and dry, and burning -- such foods are desired by the rajasic [person], 'producers of pain, grief, and disease' -- [meaning] because they produce pain, and grief, and disease, [they are] 'producers of pain, grief, and disease.'