PECULIARITIES OF THE HORSE MEAT AGING
Over the last decade the horse meat has gone deeper into the field of vision of both consumers and scientists. The objective of this study is to identify the specific features during aging of the horse meat. The changes in microstructure, morphology, protein autolysis, soluble proteins, pH, WHC, drip loss and colour were studied in horse m. Longissimus dorsi during 12 d of wet aging at 0 - 4°C. At 3 d post mortem the A- and I-zones were more difficult to distinguish. Some shortening of the sarcomere was observed. The rigor mortis period in the horse meat occurs between day 3 and day 5. Within this period the muscle fibres were contracted, the red colour component was decreased by 2 - 3 units, the pH and the WHC were minimal - 5.80 and 13 - 14%, respectively, and the drip losses were maximum about 20%. Intra-cellular spaces released free water was found. After 5 d post mortem single cracks and strains were observed - an indicator of the ongoing autolytic processes. The solubility of the proteins stabilized at about 1.750 mg/ml. An increased share of protein fractions with a molecular weight of 28 - 23 KDa, considered as an indicator of increased meat fragility, was found after 5 days. From 5 to 12 d, higher levels of α-actinin, deskman and light meromyosin were found. After 7 d of post mortem the destructive changes were deepening. Z-lines were very much torn. A- and I-discs were difficult to distinguish. Myofibrils were highly fragmented and I-zones were not distinguishable.