Researchers have found that morphology of muscle structure (original or after processing) is closely related to meat tenderness, which is very important attribute for consumer. The aim of the study was to evaluate changes in microstructure of poultry meat during the chilled storage. In the study, the cross-cut microstructure of parents stock hen and broiler muscles were analyzed during the storage at + 1 +- 0.5 °C temperature. The changes were determined for the following muscles: musculus pectoralis and pars praeacetabularis musculus iliotibialis lateralis in seven hours after slaughter and on the 7th day of storage. Parents’ stock (PS) hens were slaughtered on 61st week, but broilers at the age of 42 days (on the 6th week). The decrease in area of muscle fibres of hens and broilers' musculus pectoralis was found in both types of meat when comparing the sample on 7th hour and 7th day, but the smaller decrease was observed in broilers meat. Comparing muscle fibre area of broiler and hen pars praeacetabularis musculus iliotibialis lateralis [musculus biceps femoris] in hen meat it was reduced in higher proportion, but the distance between the fibres was increased reaching similar values for both sample types.

The production of innovative composition (high omega group fatty acids and antioxidants-carotenoids) broiler chicken meat and egg opportunities in Latvia was assessed. After feeding the poultry with feed enriched with fatty acids and antioxidants, broiler meat and eggs of innovative composition containing a higher amount of omega-3 (in meat by 1.7%, in eggs by 2.7%), omega-6 (in meat by 3.9%, in eggs by 3.2%) and carotenoids (0.44 mg kg-1 in meat and in eggs by 6.9 mg kg-1) when compared with the content of commercial products are obtained. Nutrition costs of innovative composition-based broiler chicken meat production are LVL 20 higher and nutrition costs of egg production are LVL 1.49 higher per 1000 units of output than in the standard version of the poultry feeding-stuff. The poultry farming production of an innovative composition, however, is economically profitable due to the higher rates of poultry productivity. In the case of an innovative composition-based yield the potential profit at the currently equal cost realisation of poultry meat and eggs is higher when calculating 293.47 LVL per 1000 broiler chickens and 5.52 LVL per 1000 eggs in comparison with commercial production.

The aim of this study was to evaluate physical and chemical changes in sous vide cooked marinated parent stock hen breast meat during refrigerated storage. Sous vide method is suitable for preparation of ready-to-eat meat products satisfying consumer demand for convenience and safety. Meat tenderness is recognized as important quality attribute of meats. The study involved preparation of the raw material, vacuum packaging of the products in polyamide/polyethylene (PA/PE) film pouches, marinating for 20 hours, sous vide cooking and chilling in ice water, followed by storage at 3.0±0.5 deg C. Each sample containing a chicken portion or chicken mix with shredded carrots, sea buckthorn sauce and spices was analysed during storage. Water activity, pH, and moisture were assessed during storage. Hardness (shear force) measurement was used as an instrumental method for meat tenderness evaluation. The differences between two studied products were noted regarding all studied parameters – water activity, pH, moisture content, and hardness. The differences mainly were determined by the properties of carrot and sea buckthorn additive, which generally have higher moisture content and lower pH. The researched parameters were well preserved during refrigerated storage for 28 days.

Meat is muscle tissue from animals. It is a good source of protein. The meat of various species also is good source for micronutrients and vitamins. Ostrich meat differs from the meat of other animals. It is no fat; it is lean and easily separated from bones and connective tissue. It is more digestible compared to other types of meat, soft and does not require long culinary treatment. Although it can be compared with beef due to its red colour and taste, ostrich meat is as tender as chicken meat, and is characterized by short muscle fibre. The objective of study was to determine the A, E, B1, B2 and B5 vitamins content in ostrich meat and compare it with beef and chicken produced in Latvia and available at retail. All vitamins are determined by standard methods according to AOAC Official Standard Methods: vitamin A - 974.29, vitamin E - 971.30, vitamin B1- 986.27, vitamin B2 - 970.25, and vitamin B5 - 961.14. The obtained results showed that ostrich meat contains significant quantities of vitamins B1, B2 and B5. The highest content in ostrich meat was calculated for B5 (11.45 mg 100gE-1) and the lowest - for B2 (0.098 mg 100gE-1). Ostrich meat contains more than 18 % of vitamins B1 and B2 and more than 7.5 % of B5 compared with beef, and more than 30 % of vitamins B1 and B2 and more than 27 % of B5 compared with chicken. The content of vitamin E is highest in ostrich meat then follows chicken and beef. Regarding vitamin A, ostrich meat has only traces of it.

Several farmers of Latvia have established ostrich substituting traditional animal growing farms. Ostrich meat is frequently described as a healthy alternative to other meat products. Ostrich, a red meat, is even lower in calories, cholesterol and fat than skinless chicken and turkey, while remaining high in the content of iron and protein. The aim of the investigation is to evaluate the chemical composition of frozen ostrich meat obtain in Latvia and compare it with other meats. The samples of meat for experiments were obtained from ostrich meat producers. Moisture content was determined by drying of the samples at 100 deg C to a constant weight (ISO 6406). Protein content was determined by Kjeldahl method (ISO 5983). Fat content was determined by Soxlet extraction method (ISO 6492). The calories in different meats were determined by an approved procedure which includes summing of the calories from fat and from protein. The investigations showed that there were no significant differences between the main components of ostrich meat produced in Latvia and those found in the data in literature. Chemical composition of ostrich meat does not significantly differ from that of other types of meat. The research suggests that ostrich meat can be substituted for beef or chicken in any recipe, including meat-processing products.