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Description of the subject. This article aims to characterize the fat content of raw ewe's milk, collected locally in the Algerian central steppe, an area highly appreciated for its production of smen (traditional butter). Objectives. The objective of this study was to investigate the free fatty acid profile and the cholesterol and lipid indexes of raw ewe's milk from two Algerian local breeds (Ouled-Djellal and Rumbi). Method. Milk was collected from 20 ewes of each breed three times during the middle stage of lactation. The milk fat was extracted using the Rose-Gottlieb method. Fatty acids were analyzed by gas chromatography. Results. Palmitic (24.4% +/- 3.3), oleic (24.2% +/- 4.6), stearic (10.8% +/- 3.5), myristic (10.4% +/- 1.9) and capric (8.3% +/- 3.5) acids dominated and accounted for 78.1% of the total fatty acids. Saturated fatty acids predominated compared to unsaturated fatty acids (69.6% +/- 5.3 vs 30.8% +/- 5.1), and monounsaturated fatty acids outweighed the polyunsaturated (26.3% +/- 4.7 vs 4.5% +/- 1.1). The Ouled-Djellal milk had a higher short-chain fatty acid content than the Rumbi milk (p < 0.05). On the other hand, the Rumbi milk was richer in medium chain fatty acids. The two types of milk differed significantly regarding their palmitic and palmitoleic acid content (p < 0.05). Within the long chain of fatty acids, only the stearic acid (10.88% +/- 2.83 vs 12.34% +/- 2.75; p < 0.01) and the arachidic acid (0.26% +/- 0.18 vs 0.35% +/- 0.09; p < 0.05) were influenced by the breed. Conclusions. Results showed that milk from the Rumbi ewe was richer in fatty acids than the milk from the Ouled-Djellal and that Rumbi ewe's milk may be of value in dairy technology due to the socio-economic impact that it can generate.

Ancien Id ProdINRA 356174; Description of the subject. This article aims to characterize the fat content of raw ewe's milk, collected locally in the Algerian central steppe, an area highly appreciated for its production of smen (traditional butter). Objectives. The objective of this study was to investigate the free fatty acid profile and the cholesterol and lipid indexes of raw ewe's milk from two Algerian local breeds (Ouled-Djellal and Rumbi). Method. Milk was collected from 20 ewes of each breed three times during the middle stage of lactation. The milk fat was extracted using the Rose-Gottlieb method. Fatty acids were analyzed by gas chromatography. Results. Palmitic (24.4% +/- 3.3), oleic (24.2% +/- 4.6), stearic (10.8% +/- 3.5), myristic (10.4% +/- 1.9) and capric (8.3% +/- 3.5) acids dominated and accounted for 78.1% of the total fatty acids. Saturated fatty acids predominated compared to unsaturated fatty acids (69.6% +/- 5.3 vs 30.8% +/- 5.1), and monounsaturated fatty acids outweighed the polyunsaturated (26.3% +/- 4.7 vs 4.5% +/- 1.1). The Ouled-Djellal milk had a higher short-chain fatty acid content than the Rumbi milk (p < 0.05). On the other hand, the Rumbi milk was richer in medium chain fatty acids. The two types of milk differed significantly regarding their palmitic and palmitoleic acid content (p < 0.05). Within the long chain of fatty acids, only the stearic acid (10.88% +/- 2.83 vs 12.34% +/- 2.75; p < 0.01) and the arachidic acid (0.26% +/- 0.18 vs 0.35% +/- 0.09; p < 0.05) were influenced by the breed. Conclusions. Results showed that milk from the Rumbi ewe was richer in fatty acids than the milk from the Ouled-Djellal and that Rumbi ewe's milk may be of value in dairy technology due to the socio-economic impact that it can generate.

L'évaluation du « grain de viande » est une appréciation subjective, utilisée par certains chevillards et bouchers pour sélectionner et orienter les carcasses, un grain extrêmement fin étant synonyme de qualité. Pour évaluer la pertinence de cette notion quatre études ont permis i) d’objectiver la notion de grain de viande par une approche ethnologique, ii) de formaliser ce savoir-faire dans une grille de notation en vif et en carcasse, iii) d’évaluer les propriétés physicochimiques des quatre muscles utilisés par les experts pour juger une carcasse, et iv) d’évaluer l’existence d’un lien entre l’évaluation du grain de viande et la qualité sensorielle des viandes. Les seize indicateurs consignés dans la grille établie sur la carcasse sont répétables et facilement utilisables en abattoir. Sur le muscle longissimus thoracis, les grains fins ont été caractérisés par des teneurs en lipides intramusculaires significativement plus faibles que les grains grossiers, conduisant à des notes d’intensité de flaveur également significativement plus faibles, mais sans répercussions sur les notes de jutosité. Il n’est pas apparu de différence significative de tendreté entre les muscles à grains fins et grossiers. Au niveau physicochimique, le grain fin a été associé à des muscles nécessitant une moindre force de cisaillement sur la viande cuite et présentant une moindre teneur en collagène, sans différence sur sa solubilité, laissant supposer un effet favorable sur les propriétés sensorielles. Les écarts sont cependant très dépendants du muscle étudié et méritent d’être confirmés à plus grande échelle., The assessment of the meat “grain” size is an empirical method used by some butchers in France to predict the tenderness of meat: the finer the grain the higher the quality. Four studies are presented here. After a characterization of this notion using an ethnological approach, two grids were built to objectivate the way of evaluating grain of meat on live animals and carcasses. The second aim was to characterize the main muscles used by the experts to rate the grain of meat. The last aim was to establish the relation between the score of meat grain estimated on the carcass and the tenderness of the longissimus thoracis muscles estimated by sensory evaluations. A group of 16 criteria were identified on the carcass as effective to anticipate overall “grain of meat” score. “Fine grain” carcasses were associated with lower lipid content than “coarse grain” in longissimus thoracis muscles, leading to significantly lower scores of flavor intensity without any impact on juiciness scores. No significant relation appeared between grain of meat and tenderness. The shear force needed to cut a broiled sample was found significantly higher for “coarse grain” carcasses than for “fine grain” ones. The total collagen in the “coarse grain” group was significantly higher than those from the “fine grain” group without any impact on collagen solubility. Taken together, these results allow hypothesizing that “fine grain” could have a positive impact on meat quality traits. The differences underlined are nevertheless very muscle-dependant and remain to be confirmed in larger trials.

La viande de palmipèdes gavés se distingue de la viande de palmipèdes non gavés surtout par son enrichissement en lipides (teneur multipliée par deux) qui modifie la qualité nutritionnelle et sensorielle des produits et leur aptitude à la conservation. Toutefois, ces caractéristiques peuvent fortement varier selon l’itinéraire technique mis en oeuvre pendant les phases d’élevage et de gavage et en particulier en fonction de la composition et des modalités de distribution de l’aliment, de l’âge à la mise en gavage et de sa durée. Les étapes de pré-abattage et la technologie d’abattage et de transformation sont également importantes à considérer. Les paramètres génétiques de la qualité de la carcasse et de la viande ont surtout été étudiés chez le canard. Ces critères de qualité sont dans l’ensemble faiblement héritables. Récemment, plusieurs QTL ont été mis en évidence en particulier pour les pertes à la cuisson, le pH et la texture de la viande. La connaissance des gènes impliqués dans le contrôle de ces paramètres devrait permettre à plus ou moins long terme de les inclure dans les schémas de sélection., The meat of overfed ducks and geese is quite different from that of waterfowl fed ad libitum, particularly because of its higher lipid content (2-fold more) affecting the nutritional and sensorial quality of products and their storage ability. However, these characteristics can be quite variable according to the technical conditions used during rearing and overfeeding periods such as the composition and distribution modalities of diets, age at the beginning of the overfeeding period and duration of overfeeding. The pre-slaughter conditions and the slaughtering and processing technologies are also important. The genetic parameters of carcass and meat quality traits have been mainly evaluated for ducks. Meat quality traits are weakly heritable. Recently, few QTL have been highlighted particularly for cooking loss, pH and meat texture. The knowledge of the genes involved in the control of these parameters should in the short or long term allow including them in selection programmes.

National audience; The monogastric meat of today differs from that produced by the animals 50 years ago. The selection of animals according to growth performance has modified the sensorial and nutritional qualities of the meat. The carcass is less fat and the animals are slaughtered younger at the same weight. The lipid content of the meat is thus decreased. However, in the medical world, meat still has a negative image of being a fat meat whereas this is no longer the case. The rearing conditions influence the quality of monogastrics meat. The feeding level and the fat matter in the diet determine the rate and composition of growth (lipids/proteins) and influence the fatty acids composition. The lipid composition of tissues highly depends on the lipid composition of the diet. Therefore, the fatty acid profile of meat (n-3 fatty acid content for example) can be easily modified through feeding, thereby improving the meat quality for the consumer and meeting the nutritionist’s requirements.

Using a great amount of published and unpublished data, this paper analyzes changes in the protein content of the empty body of growing cattle and sheep (appendices 1, 2). Protein content (p. 100 of empty body weight) usually increased from 6-7 p. 100 to 18-20 p. 100 in cattle and to 14-18 p. 100 in sheep during foetal life. After birth, it decreased slowly, reaching 13-15 p. 100 in 70 p. 100 mature-weight animals. Changes in water and lipid content were analyzed in relation to protein content (fig. 1). Protein content (p. 100 of fresh weight) varied between 10 and 14 p. 100 in the adipose tissues, 15 and 16 p. 100 in the offals, 19 and 20 p. 100 in the muscles and skeleton and 28 and 30 p. 100 in the hide. Muscle protein amounted to 48 to 53 p. 100 of whole body protein. Mean daily protein accretion increased in cattle from 100 g after birth to a maximum of 160-200 g/day at 200-300 kg of body weight and decreased afterwards (fig. 3). From 20 g/day in very young lambs, it reached 30-40 g/day at 20-30 kg of body weight. Daily protein accretion in g per kg of metabolic weight (W0.75) was similar in the two species (5.5 g at birth, 2.8 g at 30 p. 100 mature body weight and 1.2 g at 60 p. 100 mature body weight). The lipid deposition was greater than protein accretion after 10 p. 100 mature body weight in sheep, but only after 20 p. 100 mature body weight in cattle. The ratio between lipid deposition and protein accretion was greater in sheep than in cattle. Daily protein accretion, which varied according to sex and genotype, ranged between 150-235 g/day in cattle and between 32-54 g/day in sheep. The protein content of sheep and cattle gain dropped when the feeding level increased. Simultaneously, the lipid content of gain increased and the animals were fatter at slaughter. However, it appears that the composition of sheep gain was less sensitive to feeding level than that of cattle.