Пенчев, Иван; Penchev, Ivan

Проучване на химичния състав, технологичните и органолептичните качества на месо от некастрирани и кастрирани мъжки прасета

Study of the chemical composition, technological and organoleptic qualities of meat from entire and castrated male pigs

2019

Thesis

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прасета; месо; химичен състав; технологични качества; органолептични качества

The objective of this dissertation thesis was to study the chemical composition, technological traits and incidence of boar taint of meat from entire male and castrated pigs. The study was carrier our in a slaughterhouse in Stara Zagora, Bulgaria. Total of 387 pigs (307 entire male and 80 castrated) were investigated. The pigs were reared under uniform feeding and housing conditions and fattened to average live weight of 90 kg. The „M. longissimus thoracis et lumborum (LTL) and M. semimembranosus (SM) were sampled for proximate analysis, and evaluation of technological and organoleptic traits. In the slaughter of pigs, all requirements of Ordinance ‡‚22 from 14.12.2005 (reduction to minimum the suffering of animals during slaughter) were observed. Meat „‚„N values were measured on 45 min (pH1) and 24 h (pH2) post mortem by means of Testo 205 „‚„N-meter. Detection of boar taint was done by a trained evaluator who smelled heated fat tissue by the so-called hot iron method (Aluwe et al., 2012). The boar taint score was evaluated on a 4-point scale as followed: .0 g - lack of boar taint (odourless); g1 g - weak perceptible boar taint; g2 g - perceptible (pronounced) boar taint and g3 g - strong (offensive) boar taint. The proximate analysis comprised water, protein fat, mineral and dray matter contents of pork meat (Bulgarian State Standard . BSS 5712, 1974; BSS 8549, 1992; BSS 9373, 1980; BSS 9374, 1982). The water holding capacity of both muscles was determined by the method of Zahariev and Pinkas (1979). Cooking loss was evaluated after roasting meat samples at 150 ‹„R for 20 min. Meat marbling was evaluated on M. longissimus thoracis et lumborum (LTL) according to the standard of the National Pork Producers Council, USA (NPPC, 1999). One point of the NPPC score corresponded to 1% intramuscular fat content. The analysis of results from chemical analysis and technological traits evaluation of pork meat from entire and castrated male pigs allowed concluding that fattening entire male pigs to 90 kg have some significant effects on meat chemical composition. The meat of entire male pigs was outlined with insignificantly lower fat and higher water and protein content than castrated pigs. Surgical castration of male pigs has no effect on the mineral content of the meat. Some technological traits of meat: pH, PSE meat, WHC and cooking loss not differed significantly between the evaluated two groups of male pigs. Surgical castration of male pigs has a significant impact on the color, tenderness and marbling of the meat. Raw meat in entire male pigs has higher L *, a * and b * values and a higher marbling than that of castrated male pigs. This should be taken into consideration by technology experts during pork quality scoring as well as at the time of making recipes for production of cooked and raw meat products. A relatively high incidence of unpleasant boar taint in the meat of entire male pigs was found. Half of the tested entire male pigs from the crossbreed "F1" have signs of an unpleasant boar taint. Surgery castrated male pigs also detect meat with signs of boar taint but only with "Grade 1". Data about the prevalence of boar taint of meat suggested that fattening entire male pigs to a body weight of 90 kg could pose some problems for modern pork production.