الفهرس 
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Abstract
Cheese is one of the most popular food products consumed in the world. It is high in protein, calcium, essential fatty acids as well as nutritive values. Determination of quality level of cheese is based on applying standard sensory test in order to screen the deficiencies originating from the technology, microbiological contamination and the degree of cheese maturity. Based on the abovementioned basis it was worthwhile to study the ripening of popular types cheeses in Egypt (Domiati, Gouda and Ras cheese) aiming to throw some light on the possibility of using the acid- base titration method (Hysteresis) as a measure for cheese quality during the ripening period as chemical composition and organoleptic evaluation. Cheese was manufactured by traditional method with 8% salt as a control and pickling in brine solution 11-12% NaCl at ambient or refrigerator temperature. Gouda cheese was manufactured under the Egyptian marketing conditions in DEINA dairy factory according to the method described by Scott, (1981) and ripened at 15 oC. Traditional Ras cheese (fresh) obtained from (AL-Nada laboratory , Mansoura) , and ripened at 15 oC. All the samples of fresh cheese and periodically during ripened for 2, 4, 6, 8, 10, 12 ,14 and 16 weeks. The obtained results can be concluded that the total solids content, acidity values, salt content, fat content, soluble nitrogen, total nitrogen content, soluble nitrogen coefficient and total volatile fatty acids increased with increasing the storage periods in all samples. The flavor, body texture, appearance & color and overall acceptability for all the samples showed improve during ripening period up to 14 weeks. The hysteresis observed in cyclic acid-base titration of cheese strongly depends on physic-chemical state of the ripened cheese-curd. The succession of titration of cheese during acidification from 7 to 5 differed from that exhibited during subsequent back-titration hysteresis loop is given by ∮▒〖∝ dpH〗.With ripening of cheese, hysteresis progressively diminishes and finally disappears. from the forgoing results, it can be concluded that the acid-base titration technique (hysteresis) as a simple and accurate analytical method could be quite informative for the soft, semi hard and hard cheese quality ripening.