Marek Stanisz

The effect of sex on the dressing percentage, carcass, and organ quality in the fallow deer (Dama dama)

Abstract Basic carcass characteristics, the quality traits of meat and internal organs from 10 fallow deer bucks and 10 does aged from 31 to 32 months were investigated. No sex effects on the bled body weight, meat yield and carcass composition were found. A significantly higher weight of mesenteric and omental fat (by 0.44 kg) was found for does. The combined share of muscle and fat in the carcass parts ranged from 77.9 to 78.5%, and the share of bones from 21.5 to 22.1%. No sex effects were found for the pH and water holding capacity measurements. Venison from males was characterized by a significantly higher thermal drip value (P=0.043) and higher L* (P=0.026), a* (P=0.010) and b* (P=0.036) values compared to does. The extracted fat content was significantly higher for females compared to males (P=0.009). The chemical analysis of deer edible by-products indicated the highest level of protein for the liver (17%), and the highest level of dry matter and fat for the tongue (33-34% and 15-18%, respectively).

Quality of meat from three muscles of farmed fallow deer (Dama dama)

The quality of three muscles (supraspinatus, longissimus, semimembranosus) were studied in a group of 12 farmed fallow deer bucks (Dama dama) aged 28 months. The aim was to compare the selected quality traits of these muscles and to assess the extent to which these traits change after 14 days of being stored in vacuum packaging. Both the pH and the temperature were significantly affected by the muscle (P < 0.0001) and the time of storage (P < 0.0001). The supraspinatus muscle had the highest initial and final pH (pH0.5 h = 6.95; pH15d = 5.93), while m. semimembranosus showed the greatest drop in temperature (by 37.5°C) 24 h postmortem. The colour parameters differed among muscles. Only lightness (L*) was not influenced by the duration of storage (P = 0.081). The 14-day storage in a vacuum bag caused a decrease in the drip loss (P = 0.002), free water (%; P = 0.001), free water (cm2; P < 0.0001) and a cooking loss (P = 0.050). The duration of time in storage caused an increase in the dry-matter (P = 0.049) and crude-protein (P = 0.044) contents and a decrease of the water to protein ratio (W : CP; P = 0.014). There was a significant effect of muscle on the dry-matter (P < 0.0001) and crude-protein (P < 0.001) contents and W : CP (P < 0.0001). The highest contents of dry matter (P ≤ 0.01) and crude protein (P ≤ 0.01) were found in m. longissimus. The highest W : CP was observed in m. supraspinatus (W : CP24 h = 4.02; W/CP15d = 3.92). The results indicated a different technological quality of the analysed muscles, and, thus, a need to further explore the background of these differences in the early postmortem period and after meat maturation.

The effect of high ultimate pH on the quality of three muscles from farm-raised fallow deer (Dama dama)

Muscles (m. supraspinatus, SP; m. longissimus thoracis et lumborum, LTL; m. semimembranosus, SM) of 16 farm-raised fallow deer were analysed to study the effect of normal and high pH on the quality of venison. While 60% of analysed SP muscles were characterised with an ultimate pH (pHu) of ≥6.0, the pHu of LTL and SM was of a normal level (pH ≤ 6.0) for most of the analysed fallow deer. The SP with a normal and high pH had the highest pHu among the analysed muscles (P = 0.009). High pHu resulted in redder meat (P = 0.004). LTL and SM with a high pHu were characterised with the lowest value of H° (P = 0.006). The drip loss and the percentage of total water were higher for SP than for the other analysed muscles (P = 0.001 and P < 0.0001). The free water and the free-water share in total water were most affected by the pHu (P = 0.001) among the analysed traits related to water-holding capacity of meat, and were lower for venison with a high pHu than for that with a normal pHu. The high-pHu venison was related to a lower cooking loss (P = 0.002) and a slightly higher meat plasticity (P = 0.027) than was the meat with a normal pHu. The proximal chemical composition of the fallow deer muscles was not influenced by the pHu (P = 0.817–0.983) nor by the carcass weight (P = 0.121–0.964). From the present results, it can be concluded that high-pH and normal-pH venison have different qualities. This also means different culinary and technological characteristics depending on the pHu value. The incidence of high pHu was the highest in the SP.

Novel ultrasound approach for measuring marbling in pork

An ultrasound examination was done on the m. longissimus lumborum, between the 10th and the 11th thoracic vertebra, on two sides (inside and outside the thoracic cavity) of the left half-carcasses of 162 fatteners. The carcasses were classified for lean meat percentage using the SEUROP system. The R pig carcasses (47.7% lean) had the thickest backfat (30.6mm; P≤0.01) and the highest content of intramuscular fat (IMF=2.28%; P≤0.01). More artifacts-free images were collected from the inside compared to the outside of the pig carcasses (90.1% vs. 58.6%; P≤0.01). The percent of bright pixels (PBP) was the highest for the inside, for all the lean-meat-content classes (P≤0.01). The correlation between the PBP and the IMF was higher for the images of the inside compared to the outside (r=0.811; P=0.001 vs. r=0.523; P=0.009). The ultrasound images of the inside of the carcasses proved to be the most useful for making an assessment of the marbling.