Patent ID: 8389037

Claim:
A method for treating cooking oil in a fryer to preserve the oil during deep fat frying, which method comprises: providing an hydraulically set product in the form of a stand-alone block or briquette which has been dried after hydraulic setting to remove free water and packed in film or sheet of packaging that resists the ingress of water or water vapour, the product consisting of >50 wt % of a mixture of milled white OPC clinker and white OPC, and optionally further ingredients selected from silica 1-2 wt %, titania (TiO 2 ) 1-2 wt %, calcium silicate, magnesium silicate, aluminium silicate, natural feldspars, natural sodium zeolites, natural calcium zeolites, synthetic sodium zeolites, synthetic calcium zeolites, wollastonite, calcium hydroxide, clays, pillared clays, activated clays/earths, talcs/kaolinite, amphiboles, granite porphyry, rhyolite, agalmatolite, porphyry, attapulgite, diatomaceous earth, and the product having the properties that calcium and magnesium substantially do not leach into the oil and that it is porous so that oil can diffuse into it and contaminants can be deposited on and within it; adding the product to the oil while the oil is cool; and heating the oil to cooking temperature.