Glycolytic and energetic resources as the determinants of meat quality of Duroc fatteners

The aim of this study was to determine the diagnostic value of glycolityc and energetical quantities on selected meat quality characteristics of Duroc fatteners. A total of 40 Duroc porkers were investigated. Among two analysed sets of determinants (R1 with glycogen and R1 with lactate) measured in 45 min after slaughter, the best diagnostic value for meat quality characteristics exhibit a set involving R1 and glycogen that composed determination coefficient (RC2) was 0.66 for pH measured in 45 min up to 144 h post mortem. Also, with currently used meat diagnostic methods the most useful one that explains the glycolytic and energetic quantities in the highest degree is method that exploits 5 determinants, i.e. pH1, pH24, EC2, EC24 and L*24. Higher composed determination coefficient and canonical correlation (CR) for this method was obtained for set involving R1 and lactate – 0.41 and 0.64** respectively

PRZEWODNOŚĆ ELEKTRYCZNA MIĘSA WIEPRZOWEGO JAKO WSKAŹNIK JEGO JAKOŚCI

The performed experiments allowed determining to what extent meat electrical conductivity measured at two time intervals (EC90’ and EC24h) may affect significantly the selected pork meat quality parameters. The experimental material comprised 75 carcasses, of which 32 were carcasses derived from hogs of line 990 and 43 were carcasses of Danish hybrid hogs [(L x Y) x Du]. The following parameters were investigated: electrical conductivity (EC90’ and EC24h), thermal drip and water holding capacity content as well as meat texture (tenderness and juiciness). After the assessment of meat electrical conductivity, the obtained results were divided into three groups taking into consideration differences in their values: EC90’: up to 3.50 mS/cm; from 3.51 – 5.00 mS/cm; > 5.00 mS/cm, and EC24h measurement: up to 4.99 mS/cm; from 5.00 – 8.00 mS/cm; > 8.00 mS/cm. It is clear from the performed investigations that measurements of meat electrical conductivity carried out 24 h after the slaughter of animals, in comparison with the measurements taken 90’ after slaughter, was correlated with the examined meat parameters higher degree

ELECTRICAL CONDUCTIVITY AS AN INDICATOR OF PORK MEAT QUALITY

The performed experiments allowed determining to what extent meat electrical conductivity measured at two time intervals (EC90’ and EC24h) may affect significantly the selected pork meat quality parameters. The experimental material comprised 75 carcasses, of which 32 were carcasses derived from hogs of line 990 and 43 were carcasses of Danish hybrid hogs [(L x Y) x Du]. The following parameters were investigated: electrical conductivity (EC90’ and EC24h), thermal drip and water holding capacity content as well as meat texture (tenderness and juiciness). After the assessment of meat electrical conductivity, the obtained results were divided into three groups taking into consideration differences in their values: EC90’: up to 3.50 mS/cm; from 3.51 – 5.00 mS/cm; > 5.00 mS/cm, and EC24h measurement: up to 4.99 mS/cm; from 5.00 – 8.00 mS/cm; > 8.00 mS/cm. It is clear from the performed investigations that measurements of meat electrical conductivity carried out 24 h after the slaughter of animals, in comparison with the measurements taken 90’ after slaughter, was correlated with the examined meat parameters higher degree.W pracy oceniano, w jakim stopniu przewodność elektryczna mięsa, mierzona w dwóch przedziałach czasowych (EC90’ i EC24h), ma istotny wpływ na wybrane wyróżniki jakości mięsa wieprzowego. Materiał doświadczalny stanowiło 75 tusz, w tym: 32 tusze wieprzków świń linii 990 i 43 tusze wieprzków mieszańców świń duńskich [L x Y) x Du]. Ocenie poddano następujące parametry: przewodność elektryczną (EC90’ i EC24h), wyciek termiczny i wodochłonność (WHC) oraz teksturę mięsa (kruchość i soczystość). Następnie uzyskane wyniki podzielono umownie na 3 grupy, w zależności od wartości przewodności elektrycznej (EC90’: do 3,50 mS/cm; 3,51 – 5,00 mS/cm; > 5,00 mS/cm i EC24h: do 4,99 mS/cm; 5,00 – 8,00 mS/cm; > 8,00 mS/cm). Z przeprowadzonych badań wynika, że pomiar przewodności elektrycznej mięsa wykonywany w 24h, w porównaniu do jej pomiarów w 90’ po uboju tuczników, był w wyższym stopniu skorelowany z ocenianymi parametrami mięsa

The Use of Chosen Physicochemical Indicators for Estimation of Pork Meat Quality

The present work aimed to estimate the usefulness and effectiveness of selected physicochemical indicators in the evaluation of meat quality as well as culinary and processing value using a simple and canonical phenotypic correlation method. Studies were carried out in 495 porkers. The most relationships were obtained for the adenosine triphosphate (ATP) breakdown indicator (R1), electrical conductivity (EC) and glycolytic potential (GP) with meat quality traits that are non-diagnostic criteria, i.e., lipids and protein content, water holding capacity (WHC), technological yield (TY), drip loss (DL) and meat tenderness (MT). The results of this study indicate that about 62% of the variability in meat quality is the result of the initial level of glycogen in muscle tissue. The strong relationship between EC2 and pH24 (acidity of the muscle tissue at 24 h after slaughter) parameters and a wide spectrum of traits of meat quality (sets covering the parameters of the culinary and processing quality of meat and indicating the volume of drip loss), as well as with the pH1 and R1 criteria confirms the possibility to perform a quick and cheap ‘on line’ classification of qualitative meat properties in meat processing plants

Przydatność wybranych parametrów oznaczanych 45 min post mortem w mięśniu Longissimus Lumborum do oceny jakości wieprzowiny

The objective of the research performed was to evaluate the usefulness of the following parameters: contents of lactic acid and glycogen, pH45, and electrical conductivity (EC2) in Longissimus Lumborummuscle (LL) to evaluate the quality of pork. The above named parameters were determined 45 min post mortem, and, additionally, the electrical conductivity was measured 2, 3 i 24 h after slaughter. It was proved that the determination of the content of lactic acid and EC2 in the LL muscle was more useful for the pork quality evaluation. This is confirmed by the statistically significant correlations among those parameters and the majority of physical-chemical properties of the LL muscle. The statistically significant negative correlation (p ≤ 0.01) between the content of lactic acid determined 45 min post mortem and the pH45 value of the LL muscle (r = -0.72**) suggests the usefulness of those parameters in evaluating the pork quality. The increase (45 min post mortem) in the lactic acid content by 10 μmol/1 g of the muscle tissue contributes to the decrease in pH45 of the LL muscle by as much as 0.1 unit.Celem przeprowadzonych badań było określenie przydatności takich parametrów, jak: zawartość kwasu mlekowego i glikogenu, pH45 oraz przewodność elektryczna (EC2) w mięśniu Longissimus lumborum (LL) do oceny jakości wieprzowiny. Wymienione parametry oznaczano 45 min post mortem, a dodatkowo przewodność elektryczną mierzono po 2, 3 i 24 h po uboju. Wykazano większą przydatność oznaczania zawartości kwasu mlekowego i EC2 w mięśniu LL do oceny jakości wieprzowiny. Potwierdzeniem są statystycznie istotne zależności tych parametrów od większości cech fizykochemicznych mięśnia LL. Statystycznie istotna (p ≤ 0,01) ujemna zależność pomiędzy zawartością kwasu mlekowego oznaczonego 45 min post mortem a pH45 mięśnia LL (r = -0,72**) wskazuje na przydatność wykorzystania tych pomiarów do oceny jakości wieprzowiny. Wzrost zawartości kwasu mlekowego (45 min post mortem) o 10 µmol/g tkanki mięśniowej przyczynia się do obniżenia pH45 mięśnia LL aż o 0,1 jednostki.The objective of the research performed was to evaluate the usefulness of the following parameters: contents of lactic acid and glycogen, pH45, and electrical conductivity (EC2) in Longissimus Lumborummuscle (LL) to evaluate the quality of pork. The above named parameters were determined 45 min post mortem, and, additionally, the electrical conductivity was measured 2, 3 i 24 h after slaughter. It was proved that the determination of the content of lactic acid and EC2 in the LL muscle was more useful for the pork quality evaluation. This is confirmed by the statistically significant correlations among those parameters and the majority of physical-chemical properties of the LL muscle. The statistically significant negative correlation (p ≤ 0.01) between the content of lactic acid determined 45 min post mortem and the pH45 value of the LL muscle (r = -0.72**) suggests the usefulness of those parameters in evaluating the pork quality. The increase (45 min post mortem) in the lactic acid content by 10 μmol/1 g of the muscle tissue contributes to the decrease in pH45 of the LL muscle by as much as 0.1 unit