S. Ribarski, A. Genchev, S. Atanasova
Abstract. The purpose of the study was to investigate the effect of cold and duration of storage at 0–4 °С on the chemical composition and technological traits of Japanese quail (Coturnix coturnix japonica) meat. It was established that water content of the studied muscles varied between 74.28 (m. Pectoralis profundus, MPP) and 75.07% (leg muscles). Protein content was 21.5–22.3% and 20% in breast and leg muscles, respectively. The fat percentage of the different muscles varied within a broad range – from 1.0 to 3.3%. The processes occurring in meat during the cold storage influenced its physico-chemical properties. The most intensive processes were observed during the first 24 hours, when meat pH decreased from 6.06–6.14 to 5.46–5.61 (breast muscles) and from 6.58–6.6 to 6.04–6.06 (leg muscles). By the 72nd post mortem hour, breast and leg meat pH retained 5.33–5.38 and 6.02–6.03, respectively. The lower meat pH reduced the hydrophilicity of muscle proteins and as a result, the water-holding capacity (WHC) by the 24th hour of m. Pectoralis superficialis (MPS) decreased at the lowest extent – 8.3%, of m. Femorotibialis (MFT) – 16.7% (Р<0.05), and the greatest reduction occurred in m. Pectoralis profundus (MPP) – 23.4% (Р<0.001). Until the 72nd hour, the WHC of the studied muscles reached a minimum – 27.0-32.8% (Р<0.001). Consequently to the reduced WHC of muscle proteins during the first 24 hours of storage, carcasses lost 1.1–1.12%, whereas until the 72nd hour – 2.54% of their weight. The recorded weight loss during the first 4 hours after the slaughter was 38.9–43.5% of the loss during the first 24 hours; and the 24-hour loss comprised 43.1–44.5% of the total weight loss. The increased acidity and lower WHC of meat resulted in altered colour traits. During the cold storage, the L* coordinate values of all muscles studied increased, with statistically significant differences for breast muscles (Р<0.01 for MPS and Р<0.001 for MPP). The coordinates а* and b* differed substantially (Р<0.001) only for MPP meat – а* values increased by 19.1%, and b* values by 59.4%.
Abstract. The purpose of this research is the reduction of feature spaces to decrease the features for qualifying the ready-to-cook minced meat products. The elaboration uses hyperspace reduction methods, through the selection of features or through the extraction of features. The capacities have been analyzed of the selection method through branches and borders selection (BBS), the method of sequential forward selection (SFS), the maximum autocorrelation factor method (МAF) and the method of multi-resolution approximation (MRA). In the experiment ready-to-cook minced meat products complying with the “Stara Planina” standard have been used. The experimental results demonstrated that the selection methods for the features are not suitable for determining the quality of ready-to-cook minced meat products in real time. For comparison of efficiency one and the same classification algorithm C4.5 has been used. The results obtained showed that a combination of MRA and МAF is most suitable for reducing the hyperspectral feature spaces of ready-to-cook minced meat products for the realization of a computer platform for objective determination of the quality of ready-to-cook minced meat products.
S. Atanassova, T. Stoyanchev, S. Ribarski
Abstract. The aim of the study was investigation of the feasibility of colour measurements and near infrared (NIR) spectroscopy as a tool for the prediction of pork meat freshness. Chilled pork loin samples (12 different batches) were collected from different retail meat markets. The meat was cut in slices 1-1,5 cm thick and placed in sterilized glass Petri dishes, in aseptic laboratory conditions. The samples were placed in cooling incubator for storage at 6°С for 10 days. On the day of samples preparing, as well as on the 3, 7 and 10 day during storage meat samples from each batch were taken for measurement. Biochemical and microbiological parameters – pH, amino acid nitrogen and total bacterial count were determined. Colour measurements were made by portable colorimeter Lovibond RT and data were presented as three-dimensional coordinates L*, a* and b* in the colorimetric system CIELab. NIR measurements were performed by NIRQuest 512 spectrometer in the region 900-1700 nm using reflection fibre-optic probe. Partial least square regression with internal cross-validation was used for calibration models development for determination of tested parameters on the base of spectral data.Differences in both colour coordinates and nearinfrared spectral data of fresh and spoiled meat samples were found. Colour measurements of meat samples in our experiment did not allow accurate determination of parameters, characterizing meat spoilage. The most significant spectral differences were observed in the region from 1360 to1470 nm and at 1642nm. Determination of pH, amino acid nitrogen and total bacterial count by PLS regression on the basis of near-infrared spectra showed good accuracy of determination for pH and amino acid nitrogen content and very good accuracy of determination of total bacterial count. The results demonstrated that the NIR spectral measurement is superior to colour measurement for predicting microbial contamination and meat spoilage.
E. Petrova, S. Stoykov
Abstract. The interest in studies of the nearby coastal zone of the Black Sea is great because it is the most productive section of the basin. The variety of habitats, water aeration, good temperature and density of nutrients coming from the nearest land and littoral contribute to the development of intensive life in it. In this area there are representatives of almost all groups of benthic organisms with the exception of some deep species. At the same time proximity to the coast makes it the most polluted part of the sea. Following the EU requirements pollutants are greatly reduced, which affects favourably biodiversity in the Black Sea ecosystem. 77 taxa of macrozoobenthos species were established, divided into four main groups: Polychaeta, Mollusca, Crustacea and “Diversa”. The ecological status is calculated on the Index of species diversity (H’), marine biotic index (AMBI) and multivariate Marine Biotic Index (M-AMBI). The results of the studies of macrozoobenthos from north to south in the nearby coastal area tend to improve the ecological situation in comparison with previous periods.
D. Petrova, E. Petrova, D. Gerdzhikov, V. Vachkova, R. Bekova
Abstract. The paper assessed the ecological status of Varna Bay during the autumn of 2011, according to the assessment of biotic components phytoplankton, macrozoobenthos and macrophytes in accordance with the requirements of the European Water Framework Directive WFD EU (2000). The state of Varna Bay is assessed as “good”.
D. Ivanova, N. Shopova
Abstract. The great interest toward the almond tree is due to the high value of the almond kernel as nutritional, dietetic, healing and technical raw material. The species is a plant of warm and mild climate with marked love for light. It develops in its best way in regions with short winters without big temperature fluctuation, early and sunny springs – without crucial frosts and with a lot of precipitations, and prolonged summers. During the period when the almond is in the state of rest and at an absolute minimum of the air temperatures up to minus 27.5°С in 1993 damages of the yearly growth up to 96 % were established under the form of decayed blossoms ovaries (Ivanova, 2002). The frequent warmings speed up the physiological processes and the subsequent spells of cold weather damage the generative organs – fruit-bearing buds and blossoms. The agro-climatic method for defining the conditions for winter survival is based on the accumulation of a certain active temperature sum exceeding the biological minimum needed for each stage of the development of an almond tree. The change in the active temperature sum depends on the temperature course, on the extreme values, on the duration of sun shine, as well as on the continental characteristic of the climate and on the mode of precipitations. The papers described here were conducted in the period 2000–2011 and aimed at tracing the influence of some basic meteorological elements (temperature, humidity, precipitations) during the autumn-winter period of the almond development in Plovdiv region. In relation to the scientifically justified division into regions for these plant species in Bulgaria it is necessary to clarify the role of one of the basic factors in their development – air temperature under the conditions of changing winter climatic parameters.
Abstract. The species composition, distribution, ecological-trophic structure and conservation value of macromycetes in Maglenishki Rid (Eastern Rhodopes Mts) is studied. 102 macromycetous species were registered. The predominant part of macromycetes belongs to the class Agaricomycetes (99 species), another part belongs to the Ascomycetes (2 species) and Myxomycetes (1 species). Fifteen macromycetous species are rare for the country, eleven of them of high conservation value are included in the Red List of endangered macromycetes in Bulgaria. All taxa are presented with brief chorological data and notes on their distribution in the region.
V. Ivanov, I. Yanchev, T. Raycheva, K. Stoyanov
Abstract. The current study was held in the experimental fields of Plant breeding department, Agricultural University – Plovdiv, due 2007 till 2009. The experimental plants of Ocimum were breeded as after-harvest crop. The evaluated leaf fertilizers Hortogrow (content N:P:K – 30:20:10, microelements MgO, B, Cu, Fe, Mn, Mo, Zn; content N: P: K – 20: 20: 20, microelements MgO, B, Cu, Fe, Mn, Mo, Zn; content N: P: K – 5: 50: 20, microelements MgO, B, Cu, Fe, Mn, Mo, Zn) are applied 3 times during the vegetation, between the phases start to of branching to bloom of the 2nd stage branches. The results show a positive influence of the leaf fertilization on the production and the surface of the formed leaf. The applied technology gives the possibilities to realize more than 4 tonesfresh herba from hectare.