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The extraction and quantification of fresh meat peptides in the molecular weight (MW) range between 3 and 17 kDalton (kDa) was examined, as well as their evolution during post-mortem ageing and their relation to taste intensity. Using a Tricine-sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE) method, quantification of fresh meat peptides in this MW range was possible. Correlation coefficients higher than 0.98 were found between the absolute amounts of peptides loaded on the gel and the measured amounts expressed as cytochrome c equivalents. In contrast to the extraction in the presence of SDS, extraction with 0.1 N HCl, 3% HClO(4) and 0.9% NaCl only partially recovered peptides present in fresh meat samples in both the 3-10 and 10-17 kDa MW range. A substantial increase in peptide concentration in the 3-17 kDa MW range with time post-mortem in both pork and beef fresh muscle samples was found. For grilled beef longissimus lumborum and semimembranosus samples of different origin and ripening times, both the concentration of the peptides in the 3-10 kDa MW range and the intramuscular fat content were significantly related with taste panel intensity scores, while the correlation with the amount of peptides in the 10-17 kDa MW range was not significant.

The objective of this study was to evaluate the differences in biochemical, sensorial and quality characteristics of retail beef in Belgium. Four types of beef (Belgian Blue double-muscled, Limousin, Irish and Argentine) and two different muscles (longissimus lumborum and semimembranosus) were bought at the retail level and compared with regard to colour, shear force, collagen content, fatty acid analysis, taste panel evaluation as well as flavour analysis. Belgian Blue and Limousin beef had a paler colour, lower collagen and intramuscular fat contents. Fatty acid profiles were significantly different between the four types, with significantly higher PUFA/SFA and n-6/n-3 ratios for Belgiam Blue and Limousin beef compared to Argentine and Irish beef. There were significant differences between the meat types for taste panel tenderness and shear force, however both measurements did not fully correspond. Flavour analysis by gas chromatography-mass spectrometry as well as sensory analysis demonstrated that Irish and Argentine beef had a higher flavour intensity related to higher contents of volatile compounds. Differences in tenderness and flavour between the meat types were probably affected by differences in ageing time, related to import vs local production of meat.

International audience; A perspective paper was synthesized during the workshop “How can we approach consensus on the healthiness of red meat?” held in Oslo, Norway, in November 2013 (Oostindjer et al., 2014). The resultant article contains some very interesting information and focuses on the role of red and processed meat in colorectal cancer development. However, not all comments from the co-authors were taken into account in the final manuscript, resulting in a scientifically incorrect statement in the abstract: “Epidemiological and mechanistic data on associations between red and processed meat intake and CRC are inconsistent…”. Because of the high visibility of this abstract through many websites and journals we have to strongly object to that statement.

Characteristics from the 8th rib cut: chemical composition, tissue composition after dissection, specific gravity (SG) and m. longissimus thoracis (LT) composition, collected on 17 Belgian Blue double-muscled fattening bulls were used to generate equations for predicting chemical carcass composition. Carcass composition was best predicted from chemical analysis of the 8th rib cut and the empty body weight (EBW) of the bull. Carcass chemical fat content (CCF, kg) was predicted from the 8th rib cut fat content (ether extract, 8RF, kg) by the following regression: CCF=1.94+27.37 8RF (R2=0.957, RSD =9.89%). A higher coefficient was found for carcass water (CCW, kg) predicted from 8RF and EBW: CCW=−2.26+0.28 EBW-34.28 8RF (R2=0.997, RSD=1.48%). No parameter was found to improve the prediction of CCP from EBW solely: CCP=−0.86+0.08 EBW (R2 =0.992, RSD=2.61%). Prediction equations based solely on LT composition had low R2 values of between 0.38 and 0.67, whereas no significant equations were found using SG. However, equations based on EBW had R2 values between 0.78 and 0.99. Chemical components of the 8th rib cut in combination with EBW are most useful in predicting the chemical composition of the carcass of Belgian-Blue double-muscled bulls.

Double-muscled cows of the Belgian Blue breed, ranging from ca. 680 to 880 kg live weight were slaughtered and various fat depots sampled for lipid analysis. Subcutaneous fat (SCF), intermuscular fat in m. serratus (IMF1) and m. transversalis (IMF2), kidney fat (KF) and intramuscular fat in m. longissimus thoracis (IMF3) were sampled. In IMF3 samples, polar lipids were separated from other lipid classes by thin layer chromatography. Both the proportions (w w %) and gravimetric concentrations (mg g(-1) of sample) of long-chain fatty acids were determined in total lipids of SCF, IMF1, IMF2, KF and in lipid classes of IMF3 by gas chromatography. The greatest concentration of total fatty acids was found in KF (777.6 ± 82.6 mg g(-1)), followed by SCF (721.3 ± 92.2 mg g(-1)), IMF2 (709.8 ± 72.5 mg g(-1)) and IMF1 (682.1 ± 71.6 mg g(-1)). Triacylglycerol and polar lipid fatty acid content of m. longissimus thoracis (IMF3) were respectively 8.1 ± 3.3 and 3.1 ± 0.6 mg g(-1). Fatty acid content, particularly the triacylglycerol fatty acid content in IMF3, increased (p0.01) with increasing carcass fat content. Polar lipid fatty acids in IMF3 contained a higher proportion of polyunsaturated fatty acids (32.6 ± 4.8 %) and lower proportion of saturated fatty acids (27.4 ± 5.0%) compared to the triacylglycerol fatty acid fraction (p0.01), which may reflect a prerequisite for proper membrane functioning. Internal fat depots were more saturated (p0.01) compared to SCF. The proportion of monounsaturated fatty acids differed (p0.01) between IMF1 and IMF2, possibly reflecting differences in muscle activity and functioning. Oleic (C18:1) and stearic (C18:0) acids comprised more than 60% of the total fatty acids in all anatomical locations.

Early post mortem temperature, pH, sarcomere length, colour, water holding capacity, calpain/calpastatin activities and myofibrillar protein concentrations (semi-quantative SDS-PAGE), measured at different times post mortem on 153 double-muscled Belgian Blue White bulls, were related to shear force (SF) measurements. The M. longissimus thoracis tenderised up to 8 days post mortem. SF was slightly correlated with temperature at 3 h post mortem (r = 0.20, p = 0.015), but not with pH early post mortem. Higher ultimate pH values measured at 24 h post mortem were related to darker meat, lower cooking losses and shorter sarcomere lengths. Sarcomere length was significantly related to SF, even after 12 days of ageing, suggesting that proteolytic activity was not able to overcome shortening. Up to 12 days post mortem, calpastatin and m-calpain activities were significantly correlated with SF suggesting a considerable role of calpains in meat tenderization of double-muscled Belgian Blue White bulls, although at 24 h post mortem, μ-calpain could no longer be detected. Titin, nebulin, filamin and troponin-T were degraded during the ageing period. Troponin-T was degraded by 80% between day 1 and 8. At 8 days post mortem its concentration was significantly correlated with 30 kDa (r = 0.63, p = 0.00), shear force (r = 0.39, p = 0.00), calpastatin activity at 1 day post mortem (r = 0.29, p = 0.01) and with the m-calpain/ calpastatin activity ratio at 1 day post mortem (r = −0.43, p = 0.00).

The effect of various levels of nitrite and nitrate, with and without ascorbate, in sausages prepared using 'back slopping' as inocluation, was investigated in three series of experiments. In all experiments, nitrite was rapidly depleted and nitrate formed. Nitrate was not used, probably because of the lack of (active?) micrococci in the starter sausage. Surface colour was found to be darker with increasing levels of nitrite. Irrespective of nitrate, colour stability was mainly promoted by residual ascorbate. The latter decreased with increasing nitrite levels.

One of the 10 universal guidelines for healthy nutrition in a report of the World Cancer Research Fund released at the end of 2007 is to "limit intake of red meat and avoid processed meat", as a result of the "convincing evidence" for an association with an increased risk of colorectal cancer development. In the present paper, the scientific evidence for the association between processed meats intake and colorectal cancer development is explored and the most probable hypothesis on the mechanism underlying this relationship formulated. It seems that the present state of knowledge is not well understood but relates to a combination of haem iron, oxidative stress, formation of N-nitroso compounds and related residues in the digestive tract as the causal factors. Although criticisms of the inaccurate definition of processed meats and the insufficient accounting for the large variability in composition of meat products have been expressed, it is clear that the report urges proper action by the meat and nutrition research community and the meat industry. Research items that in our view should be addressed are discussed. They include: (1) evaluating the health risks associated with processed meats intake within the context of the supply of beneficial nutrients and other nutrition associated health risks; (2) definition of the role of nitrites and nitrates in meat processing; (3) investigating the role of red and processed meats on the endogenous formation of N-nitroso compounds in the digestive tract; and (4) developing improved processed meats using new ingredients.

Three experiments were conducted to study the effect of cimaterol on meat quality and myofibrillar protein fragmentation of the Longissimus dorsi muscle. In two experiments (Experiments 1 and 2), conducted with 16 double-muscled Belgian white-blue bulls and 15 Charolais bulls, respectively, half of the animals received 60 μg cimaterol daily per kg liveweight in the diet, during 135 and 93 days, respectively. In a third experiment, 46 normal Belgian white-blue bulls received no or 4 ppm cimaterol in the diet for 246, 127 or 71 days on average. A withdrawal period of 6 days was always applied for cimaterol-treated animals. Ultimate pH, colour and waterholding capacity were not significantly affected. The effect of cimaterol on moisture content was variable, while protein content was increased and fat was reduced. Warner-Bratzler shear force values were increased by cimaterol P < 0·05 in Experiments 2 and 3 and P = 0·07 in Experiment 1). The lower tenderness cannot be explained by differences in sarcomere length or hydroxyproline content. Myofibrillar protein fragmentation was lower when cimaterol was fed, suggesting that cimaterol may reduce myofibrillar protein degradation via a lower activity of the proteolytic enzymes. Length of cimaterol administration only exerted minor effects on meat quality.

The effect of including linseed [extruded (EL) or crushed (CL)] instead of whole soybeans (S) in the finishing diet of double-muscled Belgian Blue young bulls on the fatty acid composition of the longissimus thoracis, triceps brachii and subcutaneous fat was investigated. The dietary supply of C18:2n-6 was similar in the three diets, while in the EL and CL diet the supply of C18:3n-3 was equal. No effects of diet on the saturated, monounsaturated and branched chain fatty acids were found. Including linseed in place of whole soybeans increased the total intramuscular n-3 fatty acid content significantly, mainly as C18:3n-3, while no significant effect on the total and individual n-6 fatty acid incorporation was observed in the intramuscular fat. As a consequence of the higher n-3 content, the n-6/n-3 ratio was decreased by linseed feeding. In contrast with the intramuscular fat, the subcutaneous fat showed a significantly increased C18:3n-3 proportion accompanied by a significantly decreased C18:2n-6 proportion when linseed was fed. Diet did not influence the c9t11CLA content in the intramuscular or the subcutaneous fat.

The effect of very fast chilling (VFC) of beef on several meat quality parameters was studied in semitendinous samples of three young bulls of the Belgian Blue breed. Left carcass sides were chilled conventionally. The semitendinosus of the right carcass sides were hot boned at approximately 50 min post mortem and cut longitudinally in two equal pieces. Packed in plastic bags, one piece was chilled very fast using a brine solution (3.4% NaCl, −2°C), whereas the other was chilled in a freezer (−20/−25°C, 3 m/s). The very fast chilling treatments lasted until 5 h post mortem. Samples were further chilled in a refrigerator (2°C) until 24 h post mortem. Sub-samples for meat quality measurements were taken and frozen at −18°C after an ageing period of 1, 4 and 11 days at 2°C. In three of the six cases, a core temperature of 0°C was achieved within 5 h post mortem [VFC condition; In the other cases, the VFC condition was nearly met. The brine chilling treatment in this study resulted in a higher cooling rate compared with the freezer treatment, and concomitantly in more pronounced effects. VFC resulted in increased concentrations of water extractable calcium and higher pH values at 5 h post mortem. These factors could be expected to activate the calpains and to accelerate proteolysis. This could not be confirmed by our results. Cold shortening occurred and sarcomere lengths were reduced by more than 30% in the VFC treatment compared with conventional chilling. This was reflected in much higher shear force values for the VFC samples.

Seventy six Belgian Blue (BB) bulls, with double-muscled conformation, were randomly allocated to six dietary treatments in a 2 × 3 factorial experiment. The treatments included low (N(L)=127 g CP/kg DM), medium (N(M)=153 g CP/kg DM) and high (N(H)=172 g CP/kg DM) levels of dietary protein in combination with low (E(L)=7.38 MJ ME/kg DM) and high (E(H)=8.03 MJ ME/kg DM) levels of dietary energy. Fatty acid composition was determined on total lipid samples of the M. longissimus thoracis of all animals and on the separated triacylglycerol and polar lipid fatty acid fractions of the medium-protein group. Dietary energy and protein levels influenced the carcass characteristics of BB bulls but the effects were small. Carcass fat cover score, carcass fat content and intramuscular fat content were slightly but significantly higher in the animals on the high versus the low energy diets. The overall intramuscular fat content was very low (

The importance of bacterial and meat enzymes in lipolysis and carbonyl formation was evaluated during dry sausage ripening. Sausages were prepared with and without addition of an antibiotic-antimicotic mixture. In some experiments, an extra inoculum of Micrococcaceae was added and in two experiments, glucose was omitted. Total viable bacterial counts after 21 days were lowered by at least 2 log units in the presence of antibiotics. Free fatty acid productions after 3 and 21 days, in the presence of antibiotics were not significantly lower than observed in the control sausages. Total carbonyl compounds (benzidine reaction compounds) were significantly lowered by the presence of antibiotics compared to the control sausages except when glucose was omitted from the recipe. The data suggest that lipolysis is almost exclusively brought about by muscle and fat tissue. Polyunsaturated fatty acids are liberated from the polar lipid fraction and their specific liberation is higher than for monounsaturated and saturated fatty acids. Carbonyl production from lipids seems to be independent of bacterial activity.

Carcass properties and meat quality characteristics of 32 Belgian Blue White double-muscled bulls (DM) were compared with those of 59 bulls of the same breed with normal conformation (N). DM showed superior carcass quality as revealed in increased dressing percentage, meat production yield, conformation grade, muscle/fat and muscle/bone ratios (all P < 0·001). Longissimus dorsi (LD) shear force values, drip and cooking losses at 8 days post mortem (pm) were significantly higher (P < 0·001) for DM, whereas sarcomere lengths were not different. Calpain 1 and calpastatin levels at 1 h and 24 h pm were tremendously decreased in DM as were also cathepsin B and L levels at 1 and 8 days pm (P < 0·001). As evident from semi-quantitative SDS-PAGE, these differences were accompanied by higher titin and lower 30 kDa levels (P < 0·001) in DM. Troponin-t levels were not different, but very low. Intramuscular collagen content was significantly lower in DM (P < 0·001). This suggests that lower background toughness in DM was compensated for by reduced post-mortem proteolytic tenderization. Discrepancy with literature reports regarding tenderness of DM might be related to the extreme muscularity of the Belgian Blue White breed, compared to other DM breeds. The results also suggest that reduced protein turnover might be involved in the muscle hypertrophy phenomenon within this breed, because of likely reduced levels of calpains and cathepsins in living DM animals.

A semi-quantitative determination of beef myofibrillar proteins using sodium, dodecyl sulphate polyacrylamide gel electrophoresis is described. Bovine serum albumin was used as internal standard. Results indicate a linear relationship between densitometric readings after staining with Coomassie brilliant blue R(250) and protein content. Recoveries of four pure proteins, loaded within a range of 0·5-4 μg, were between 92 and 110%. Heating of beef myofibrillar protein samples during dissolution is shown to be unnecessary. The method allows the quantitative study of myofibrillar degradation during beef aging, without overlapping of troponin-T with tropomyosin bands.

Three groups of male Friesian veal calves (in total, 92) were slaughtered in separate series. Within each group, a subgroup (selected on the basis of blood characteristics determined 1 week ante mortem) was electrically stimulated immediately after bleeding (64 s-Mitab® Low voltage unit). Carcasses were transferred ca. 25 min post mortem (pm) to a cooler at 6°C and ca 2 h pm to a cooler at 3°C. Electrical stimulation (ES) increased brightness and, to a lesser extent, yellowness, of the freshly cut surface (6th rib Longissimus dorsi, 24 h pm) but resulted also in a diminished water-holding capacity (WHC) of the veal meat. The effect of ES on tenderness (Warner-Bratzler shear force, 48 h pm) is positive for two of the three groups but negative for the third. This indicates that ES probably results in two opposite effects on tenderness-'toughening', as a result of the sarcomere shortening which occurred in all three groups, and 'tenderizing', as a result of microscopical fibre disruption. Our data indicate that disadvantages of ES may outweigh advantages when followed by moderate cooling.

The relative importance of various compounds determining pH in dry sausage was investigated using 'multiple linear regression' analysis. Analytical data were obtained for the concentrations of water, lactate, ammonia, acetate, α-amino nitrogen and salt related to sausage crude protein, using 55 different brands of dry sausage. The pH (Y) was significantly related to water, ammonia and lactate concentrations as follows: Y = 4·317 - 1·152X(1) + 0·751X(2) where X(1) = log(H(2)O) and X(2) = [log (ammonia)/(lactate) · 100] with (H(2)O) expressed as g/100g crude protein and (lactate) and (ammonia) as mmoles/100 g crude protein. The results suggest that the increase in pH often observed in the later stages of ripening is related to a decrease in electrolyte dissociation and/or an increase in the concentration of buffering proteins as well as to the formation of ammonia.