Influence of housing conditions on performance and meat quality in pigs. 2. Characteristics of muscular and adipose tissues, and technological and sensory properties of dry-salted ham

The aim of this study was to investigate the effects of an outdoor pig production system (winter and summer) compared to a classical indoor system and, for indoor system, the influence of ambient temperature and feeding level (17°C ad libitum, 17°C restricted, 24°C ad libitum), on muscular and adipose tissue traits, and technological and sensory properties of dry-salted ham.Percentage and surface of type I, IIA, IIBR and IIBW muscular fibres of Longissimus dorsi (LD, white) and Semispinalis capitis (SC, red) muscles were determined. Compared to pigs reared ad libitum at 17°C, pigs reared outdoor (winter) or restricted at 17°C exhibited a higher oxydative capacity in LD, and a lower glycolytic capacity in LD and in SC. Summer outdoor system led to a higher lipid content in Semimembranosus muscle. Firmness of external adipose tissue was reduced by winter outdoor system and feed restriction at 17°C, whereas summer outdoor system led to the higher firmness (due to the higher stearic acid percentage), but also to the higher coefficient of unsaturation of adipose tissue.Weight loss during processing of dry-salted hams was higher for pigs reared ad libitum at 17°C. Sensory analyses showed that lower ambient temperature increased bi-color appearance, and reduced intensity of meat colour for animals fed ad libitum or reared outdoor (winter). Feed restriction resulted in lower marbling of muscle. Thus, pig production systems performed in this study influenced the aspect of ham, but seemed to have no effect on the evaluation of texture or flavor by the test panel.