Paolo Polidori

Carcass characteristics, meat quality and nutritional value of horsemeat: A review

Meat has exerted a crucial role in human evolution and is an important component of a healthy and well balanced diet due to its nutritional richness. The aim of the present review was to shed light on the nutritional composition of horsemeat and their benefits for human health. One of the reasons for such interest was the occurrence, in Europe several years ago, of dioxin, Bovine Encephalopathy and foot-and-mouth disease problems in farm animals. Therefore, consumers began to look for alternative red meats from other non-traditional species. There is no carcass classification system on horses designated to meat consumption. It would be advisable to standardize the equine meat market to reduce variations that may reflect differences in meat quality. The nutritional composition of horsemeat by comparison with pork, beef or poultry is characterized by low levels of fat and cholesterol (about 20% less), relatively high concentrations of n-3 fatty acids and heme iron indicating that its consumption may be beneficial for health. Therefore, horsemeat may supplement the meat market with good quality products, although as in other dietary components moderation is advisable.

Low voltage electrical stimulation of lamb carcasses: effects on meat quality.

The effects of an early post mortem low voltage electrical stimulation (28 V, 60 Hz) on biochemical changes and on final tenderness in muscles Longissimus thoracis et lumborum and Semimembranosus from lamb carcasses were studied. It was shown that electrical stimulation accelerated the glycolytic process resulting in a significant fall in pH during the first 6 h post mortem in both muscles examined and in a significant reduction in adenosine triphosphate (ATP) content in muscle Longissimus thoracis et lumborum. The effect of electrical stimulation on tenderness was recorded by measuring shear force values 2 and 7 days post mortem. Tenderness was significantly improved by electrical stimulation for the Longissimus thoracis et lumborum both at 2 and at 7 days post mortem, while for Semimembranosus electrical stimulation significantly increased tenderness just at 7 days post mortem.

Quality of donkey meat and carcass characteristics

A study based on 15 entire donkey males was carried out to evaluate carcass quality and nutritional characteristics of meat obtained by these animals slaughtered at 15 months of age and a mean final body weight of 181kg. The meat had a low (2.02g/100g) fat content, an appreciable (22.8g/100g) protein content, and cholesterol content was 68.7mg/100g. Glycogen was also determined (0.45g/100g) within 12h of sampling. Potassium was the mineral with the highest content (343mg/100g), followed by phosphorus (212mg/100g), sodium (52mg/100g) and magnesium (24mg/100g). Donkey meat obtained from young animals can be considered a good alternative to other red meats and not only for the production salami, or other fermented meat products.

Effects of Lyophilization and Use of Probiotics on Donkey's Milk Nutritional Characteristics

Cow milk protein allergy (CMPA) is an abnormal IgE-mediated reaction to cow milk proteins. Donkey’s milk could be considered suitable for feeding young children affected by severe IgE-mediated CMPA because its nutritional properties and composition are very close to human milk. Since donkey’s milk is available during a limited range of months during the year, it may be useful to find better storage conditions for this product. This study investigated the effects of the lyophilization treatment on donkey’s milk nutritional characteristics, and the results were compared with those obtained on fresh and frozen milk. Nutritional properties of lyophilized donkey’s milk remained basically unchanged compared with fresh milk. Two different probiotic strains were added to lyophilized donkey’s milk, and their viability was evaluated after milk reconstitution. The results obtained confirmed the possibility of producing a probiotic infant formula with beneficial properties using donkey’s milk as raw material.

Donkey milk production: state of the art

Abstract Milk is one of the most common causes of food allergies among children under one year of age. No specific therapy exists for this allergy, and thus the only feasible response is to avoid assumption of milk and derived products. Studies conducted on the serum of children with hypersensitivity to milk have shown that caseins are the proteins with the greater allergenic potential. However, in some cases, children have also shown hypersensitivity to the β-lactoglobulines and to the α-lactal-bumins. When food intolerance is diagnosed in an infant, it is often necessary to impose a period of total parenteral feeding, followed by breast feeding, considered the most correct method of re-feeding. When human milk can not be given, alternative food sources must be sought. Clinical studies have demonstrated that donkey milk could substitute breast feeding in infants affected by severe Ig-E mediated milk allergies. In these subjects, donkey milk is not only useful, but also safer than other types of milk. In fact donkey milk composition in lipids (high levels of linoleic and linolenic acid) and proteins (low caseins content) is very close to human milk. Lysozyme content in donkey milk resulted to be very high (mean value 1.0 mg/ml) if compared to bovine (traces), caprine (traces) and human milk. The high lysozyme content of donkey milk may be responsible of the low bacterial count reported in literature and also makes this milk suitable to prevent intestine infections to infants. Among seroproteins, β-lactoglobulin and α-lactalbumin content in donkey milk was respectively 3.75 and 1.80 mg/ml and remained substancially the same during the different stages of lactation.

Physical and chemical characteristics of donkey meat from Martina Franca breed.

The rheological and chemical characteristics of meat obtained from 12 Martina Franca donkey males, slaughtered at 14months of age and a mean final body weight of 169kg were determined. Meat samples were taken four days post mortem from muscles Longissimus thoracis et lumborum and Biceps femoris, colorimetric parameters were measured to determine L(∗) (lightness), a(∗) (redness), b(∗) (yellowness) and chroma. The Longissimus was significantly lighter (P<0.05) compared to the Biceps femoris, with L(∗) indexes of 35.86 and 31.34, respectively. Fatty acid composition of the intramuscular fat showed a high content of polyunsaturated fatty acids (PUFAs) in both muscles, respectively 25.16g/100g total fatty acids in the Longissimus and 24.97g/100g total fatty acids in the Biceps femoris; oleic acid and palmitic acid were the two most abundant fatty acids in both muscles. The percentages of essential amino acids were higher in both muscles compared with the total amino acid content, respectively 52.88% in the Longissimus, and 51.26% in the Biceps femoris. The high level of unsaturation of the intramuscular fat resulted in a high ratio of unsaturated to saturated fat, and the total amount of essential amino acids, exceeding 50% of the total amino acids showed that donkey meat from a health point of view is a good alternative to traditional red meats.

Meat fatty acid composition of llama (Lama glama) reared in the Andean highlands

This study reports the results of the chemical analysis of the Longissimus thoracis and lumborum taken from 20 llama males, reared in the Andean highlands. The animals were slaughtered at 25 months and had a mean final body weight of 63kg. Llama meat shows a low fat (3.51%) and cholesterol content (56.29mg/100g). The fatty acid composition in llama meat contains 50.34% saturated fatty acids, 42.48% monounsaturated fatty acids and 7.18% polyunsaturated fatty acids. Llama meat appears to be a healthy alternative red meat choice.

Tenderization of wether lambs meat through pre-rigor infusion of calcium ions

A study involving 36 wether lamb carcasses was conducted in order to evaluate the effects of 0.3 M CaCl(2) injection on final tenderness in muscle Longissimus thoracis et lumborum. Injection of wether lamb carcasses with CaCl(2) accelerated the post mortem tenderization process. Both control and distilled water injected animals had similar Ca(2+)-dependent proteases (μ-calpain and m-calpain) and their inhibitor (calpastatin) activities, whereas these were all significantly decreased in CaCl(2) injected animals. The effect of CaCl(2) injection on tenderness was recorded by measuring shear force values 2 and 6 days post mortem. Tenderness was significantly improved by CaCl(2) injection at both at 2 and 6 days post mortem. It was concluded that activation of μ-calpain and m-calpain was responsible for the observed post mortem proteolysis and tenderization.

A Proteomic Study on Donkey Milk

In children with Cow Milk Protein Allergy (CMPA), when it is not possible to breast feed or to use cow milk, the clinical use of donkey milk is considered since several studies have demonstrated the high similarity of donkey milk compared to human milk. An analysis was performed on donkey milk protein profile by two-dimensional electrophoresis (2-DE) followed by N-terminal sequencing in order to give a panoramic view of the proteins that are present in donkey milk. Furthermore, the interest was focused on the casein fractions and on their phosphorylation degree that may influence the calcium binding ability of caseins. At this purpose experiments on donkey milk casein dephosphorylation have been performed and the dephosphorylated casein fractions have been identified after 2-DE analysis followed by N-terminal sequencing. Among caseins were found mainly αs1- and β-caseins that showed a considerable heterogeneity due to variable degree of phosphorylation and to the presence of genetic variants. Finally, a quantitative determination of some antimicrobial proteins, such as lactoferrin and lactoperoxidase, that could be able to stimulate the development of the neonatal intestine, was performed in donkey milk, with the results being 0.080±0.0035 g/L and 0.11±0.027 mg/L, respectively. From the obtained data is evinced that human and donkey milk contain considerable amounts of lysozyme and lactoferrin but lactoperoxidase is present only in small amounts, confirming the high similarity between donkey and human milk. The present study on donkey milk proteins may be useful to assess the nutritional characteristics of this milk that is used to feed children affected by CMPA, but also may open the possibility of utilizing donkey milk in the general population to benefit subjects with CMPA, such as adults and the elderly.

Tenderness evaluation and mineral levels of llama (Lama glama) and alpaca (Lama pacos) meat

Tenderness and mineral levels were determined in the Longissimus thoracis taken from 20 llama and 30 alpaca males reared in Peru and slaughtered at 25 months of age. Mineral contents were determined using an inductively coupled plasma emission spectrometer. Tenderness evaluation was determined two and seven days post slaughter using a Warner-Bratzler shear force device. Potassium is the mineral with the highest content, with a significant difference (P<0.05) between the two species of camelids. The other mineral contents were, in decreasing order, phosphorus, sodium, magnesium and calcium, in addition to smaller percentages of zinc and iron. Shear force values determined seven days post slaughter were significantly (P<0.01) lower in both the species compared with the results obtained two days post slaughter.