This base type goes back to a Late Latin derivation of the term for whey cheese from lat. sěrum 'whey' with -aceus, which can be located in Upper Italy, Savoy and Switzerland. The base type is mainly preserved in Francoprovençal and Occitan. From *sēraceum emerged frp. seraz, which passed into French as sérac. The French spelling preserves the -c of *sēraceum simply for graphic reasons. From the French of Western Switzerland, Rescherack 'salted whey cheese' was borrowed into Swiss German (cf. FEW 11, 495 under *serāceum; cf. Idiotikon 4, 1642 under Rescherack; cf. TLFi under sérac).