The effect of RN gene on yields and quality of extended cooked cured hams

The effect of RN- allele on minimally processed hams as manufactured in Fra nce is now well established. In the present study, meat from 35 rn(+) and 5 1 RN- pigs on the basis of their glycolytic potential (GP) was used to asse ss the effect of the RN- allele on a model system and on yields and quality of cooked hams cured with a 40% brine addition containing the most common meat processing ingredients. Quality parameters were also measured on the f resh loins and a glucose assay was carried out on meat juice from both hams and longissimus dorsi (LD) muscles. With respect to GP, glucose content of LD juice gave the best prediction of RN status with 10% misclassified samp les in comparison with 20% as determined from ham juice. Lower pH and highe r drip loss and L* values were measured on the LD from RN- pigs (p less tha n or equal to 0.001). Technological yields obtained on the model system and on extended cooked cured hams were lower in meat from RN- pigs (p less tha n or equal to 0.001). However, pH value was more influential on the yield o f the model system while protein content and particularly the amount of ext ractable sarcoplasmic proteins were more determinative on cured hams probab ly due to the effect of tumbling. All other quality traits were lower in ha ms from RN- pigs (p less than or equal to 0.001). Meat from RN- pigs can be used for the manufacture of extended cured products, but under similar pro cessing technologies, quality and yield will remain inferior to what would provide pork of normal quality. (C) 1999 Elsevier Science Ltd. All rights r eserved.