n-3 fatty acid enrichment of edible tissue of poultry: A review

There is clear evidence of the nutritional benefits of consuming long-chain n-3 PUFA, which are found predominantly in oily fish. However, oily fish consumption, particularly in the United Kingdom, is declining, as is the consumption of all meats with the exception of poultry, which has increased in consumption by 73% in the last 30 yr. This pattern, if less marked, is reflected throughout Europe, and therefore one means of increasing long-chain n-3 PUFA consumption would be to increase the long-chain n-3 PUFA content in the edible tissues of poultry. This review considers the feasibility of doing this, concentrating particularly on chickens and turkeys. It begins by summarizing the benefits to human health of consuming greater quantities of n-3 FA and the sources of n-3 PUFA in the human diet. The literature on altering the FA composition of poultry meat is then reviewed, and the factors affecting the incorporation of n-3 PUFA into edible tissues of poultry are investigated. The concentration of alpha-linolenic acid (ALA) in the edible tissues of poultry is readily increased by increasing the concentration of ALA in the birds' diet (particularly meat with skin, and dark meat to a greater extent than white meat). The concentration of EPA in both white and dark meat is also increased when the birds' diet is supplemented with EPA, although supplementing the diet with the precursor (ALA) does not result in a noticeable increase in EPA content in the edible tissues. Although supplementing the birds' diets with relatively high concentrations of DHA does result in an increased concentration of DHA in the tissues, the relationship between dietary and tissue concentrations of DHA is much weaker than that observed with ALA and EPA. The impact that altering the FA composition of edible poultry tissue may have on the organoleptic and storage qualities of poultry products is also considered.

Importance of mycotoxins in food and feed in India

Various food and feed samples including groundnut seed, maize, sorghum, soyabean cake, groundnut cake, cotton cake, poultry feed, buffalo milk, cow milk and milk powders were collected from farmers' fields, farmer's stores, oil millers storage, traders' storage, retail shops and supermarkets. More than 2000 samples were analysed by ELISA and most of the commodities, with the exception of sorghum seed, contained high levels of aflatoxin. Groundnut cake was one of the major cattle feed ingredients in the peri-urban area of Hyderabad (Andhra Pradesh, India) and >75% of the samples contained >100 µg/kg aflatoxin, leading to a high level of aflatoxin M1, in milk samples. Strategies to reduce aflatoxin levels (especially in groundnut) by management interventions at preharvest, harvest and storage, are discussed.

Effects of cultural system (organic and conventional) on growth, photosynthesis and yield components of sweet corn (zea mays L.) under semi-arid environment

Organic sweet maize consists of a new industrial crop product. Field experiment was conducted to determine the effects of cultural systems on growth, photosynthesis and yield components of sweet maize crop (Zea mays L. F-1 hybrid 'Midas'). A randomized complete block design was employed with four replicates per treatment (organic fertilization: cow manure (5, 10 and 20 t ha(-1)), poultry manure (5, 10 and 20 t ha(-1)) and barley mulch (5, 10 and 20 t ha(-1)), synthetic fertilizer (240 kg N ha(-1)): 21-0-0 and control). The lowest dry weight, height and leaf area index and sod organic matter were measured in the control treatment. Organic matter content was proportionate to the amount of manure applied. The control plots had the lowest yield (1593 kg ha(-1)) and the double rate cow manure plots the had,greatest one. (6104 kg ha(-1)). High correlation between sweet corn yield and organic matter was registered. Moreover, the lowest values of 1000-grain weight were obtained with control plot. The fertilizer plot gave values which were similar to the full rate cow manure treatment. The photosynthetic race of the untreated control was significantly lower than that of the other treatments. The phorosynthetic rate increased as poultry manure and barley mulch ram decreased and as cow manure increased. Furthermore the untreated control had the lowest stomatal conductance and chlorophyll content. Our results indicated that sweet corn growth and yield in the organic plots was significantly higher than those in the conventional plots.

Composition, color, and texture of Thai indigenous and broiler chicken muscles

Chemical compositions and physical properties of mixed-sex Thai indigenous (Gallus domesticus) and broiler (commercial breed, CP707) chicken biceps femoris and pectoralis muscles were determined. Indigenous chicken muscles contained higher protein contents but lower fat and ash contents compared to broiler muscles (P < 0.001). The amino acid profile of the indigenous chicken muscles was similar to that of the broiler muscles except they were slightly richer in glutamic acid (P < 0.05). The indigenous chicken muscles contained more saturated and less polyunsaturated fatty acids than the broiler muscles. There were no differences in the monounsaturated fatty acid contents between the breeds. The total collagen contents of indigenous pectoralis and biceps femoris muscles were 5.09 and 12.85 mg/g, respectively, which were higher than those found in broiler pectoralis (3.86 mg/g) and biceps femoris muscles (8.70 mg/g) (P < 0.001). Soluble collagen contents were lower for indigenous pectoralis and biceps femoris muscles, 22.16 vs. 31.38% and 26.06 vs. 33.87%, respectively. The CIE system values of lightness (L*), redness (a*), and yellowness (b*) of indigenous chicken muscles were higher than those of broiler muscles. The shear values of indigenous chicken muscles either raw or cooked were higher than those of broiler muscles (P < 0.05). After cooking, the shear values decreased for broiler biceps femoris and pectoralis muscles (P < 0.05), whereas no change was observed for indigenous chicken biceps femoris muscle (P > 0.05). Shear values increased for indigenous chicken pectoralis muscle (P < 0.05).

Microstructure and thermal characteristics of Thai indigenous and broiler chicken muscles

The microstructure and thermal characteristics of Thai indigenous (Gallus domesticus) and broiler chicken (commercial line CP707) biceps femoris and pectoralis muscles were determined. Perimysium thicknesses were 14.2 mum for biceps femoris muscle and 7.10 mum for pectoralis muscle of indigenous chicken muscles, thicker than those of broiler muscles, which were 9.93 mum for biceps femoris muscle and 3.87 mum for pectoralis muscle (P < 0.05). Five endothermic peaks with peak transition temperatures (T-p) of 54.9, 61.7, 65.4, 70.6, and 76.1degreesC were obtained for broiler pectoralis muscle, whereas only 3 endothermic peaks (T-P of 56.6, 62.6, and 74.9degreesC were obtained for broiler biceps femoris muscle. Thai indigenous biceps femoris and pectoralis muscles had endothermic peaks with T-P ranges of 53.5 to 54.8, 60.7 to 61.9, and 75.9 to 76.9degreesC. The fiber diameters of Thai indigenous chicken muscles were greater (P < 0.05) than those of the broiler, 31.7 vs. 20.4 mum for biceps femoris muscle and 28.9 vs. 26.6 pm for pectoralis muscle, respectively. After cooking at 80degreesC for 10 min, the fiber diameter of indigenous chicken muscles significantly decreased while those of the broiler significantly increased. The mean of sarcomere lengths of the raw muscles ranged from 1.56 to 1.64 mun and decreased to 0.92 to 1.32 mum (P < 0.001) for broiler muscles and 1.22 to 1.35 mum (P < 0.001) for indigenous chicken muscles after cooking. The perimysium and endomysium of broiler muscles melted after cooking at 80degreesC, however, only slight disintegration was observed in these tissues in the indigenous chicken muscles.

Effects of vitamin E and fish oil inclusion in broiler diets on meat fatty acid composition and on the flavour of a composite sample of breast meat

BACKGROUND: Enriching poultry meat with long-chain n-3 polyunsaturated fatty acids (LC n-3 PUFA) can increase low population intakes of LC n-3 PUFA, but fishy taints can spoil reheated meat. This experiment determined the effect of different amounts of LC n-3 PUFA and vitamin E in the broiler diet on the fatty acid composition and sensory characteristics of the breast meat. Ross 308 broilers (120) were randomly allocated to one of five treatments from 21 to 42 days of age. Diets contained (g kg−1) 0, 9 or 18 LC n-3 PUFA (0LC, 9LC, 18LC), and 100, 150 or 200 mg LD--tocopherol acetate kg−1 (E). The five diets were 0LC100E, 9LC100E, 18LC100E, 18LC150E, 18LC200E, with four pens per diet, except 18LC100E (eight pens). Breast meat was analysed for fatty acids (uncooked) and sensory analysis by R-index (reheated). RESULTS: LC n-3 PUFA content (mg kg−1 meat) was 514 (0LC100E) and 2236 (9LC and 18LC). Compared with 0LC100E, meat from 18LC100E and 18LC150E tasted significantly different, while 23% of panellists detected fishy taints in 9LC100E and 18LC200E. CONCLUSION: Chicken meat can be enriched with nutritionally meaningful amounts of LC n-3 PUFA, but > 100 mg dl--tocopherol acetate kg−1 broiler diet is needed to protect reheated meat from oxidative deterioration. Copyright © 2010 Society of Chemical Industry

Milk and meat in our diet: good or bad for health?

Foods derived from animals are an important source of nutrients in the diet but there is considerable uncertainty about whether or not these foods contribute to increased risk of various chronic diseases. For milk in particular there appears to be an enormous mismatch between both the advice given on milk/dairy foods items by various authorities and public perceptions of harm from the consumption of milk and dairy products, and the evidence from long-term prospective cohort studies. Such studies provide convincing evidence that increased consumption of milk can lead to reductions in the risk of vascular disease and possibly some cancers and of an overall survival advantage from the consumption of milk, although the relative effect of milk products is unclear. Accordingly, simply reducing milk consumption in order to reduce saturated fatty acid (SFA) intake is not likely to produce benefits overall though the production of dairy products with reduced SFA contents is likely to be helpful. For red meat there is no evidence of increased risk of vascular diseases though processed meat appears to increase the risk substantially. There is still conflicting and inconsistent evidence on the relationship between consumption of red meat and the development of colorectal cancer, but this topic should not be ignored. Likewise, the role of poultry meat and its products as sources of dietary fat and fatty acids is not fully clear. There is concern about the likely increase in the prevalence of dementia but there are few data on the possible benefits or risks from milk and meat consumption. The future role of animal nutrition in creating foods closer to the optimum composition for long-term human health will be increasingly important. Overall, the case for increased milk consumption seems convincing, although the case for high-fat dairy products and red meat is not. Processed meat products do seem to have negative effects on long-term health and although more research is required, these effects do need to be put into the context of other risk factors to long-term health such as obesity, smoking and alcohol consumption.

Long-chain n-3 PUFA: intakes in the UK and the potential of a chicken meat prototype to increase them

With the wide acceptance of the long-chain (LC) n-3 PUFA EPA and DHA as important nutrients playing a role in the amelioration of certain diseases, efforts to understand factors affecting intakes of these fatty acids along with potential strategies to increase them are vital. Widespread aversion to oil-rich fish, the richest natural source of EPA and DHA, highlights both the highly suboptimal current intakes in males and females across all age-groups and the critical need for an alternative supply of EPA and DHA. Poultry meat is a popular and versatile food eaten in large quantities relative to other meats and is open to increased LC n-3 PUFA content through manipulation of the chicken's diet to modify fatty acid deposition and therefore lipid composition of the edible tissues. It is therefore seen as a favourable prototype food for increasing human dietary supply of LC n-3 PUFA. Enrichment of chicken breast and leg tissue is well established using fish oil or fishmeal, but concerns about sustainability have led to recent consideration of algal biomass as an alternative source of LC n-3 PUFA. Further advances have also been made in the quality of the resulting meat, including achieving acceptable flavour and storage properties as well as understanding the impact of cooking on the retention of fatty acids. Based on these considerations it may be concluded that EPA- and DHA-enriched poultry meat has a very positive potential future in the food chain.

Farm business survey 2008/09: poultry production in England

The report provides a commentary on the UK poultry industry focusing on its structure, development and contribution to the UK agricultural economy. It also includes data on the economic performance of poultry businesses in England during 2008/09.

Farm business survey 2009/10: poultry production in England

A commentary on the UK poultry industry focusing on its structure, trends and development. Analysis includes the economic performance of poultry businesses in England during 2009/10.