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Changes in quality of parents stock hens meat during chilled storage
2009
Ramane, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Galoburda, R., Latvia Univ. of Agriculture, Jelgava (Latvia)
The aim was to study changes of chemical composition (fat content, protein content), pH and colour of poultry meat during chilled storage. Various criteria are used for evaluation of bird and carcass quality, while the combination of several indices determines the quality of poultry meat, which has an important role in the following meat processing and quality of end product. Chilled poultry meat is offered in retail and it is used in processing plants for various meat products production. Chemical composition (fat content, protein content), pH and colour are important quality determinants. Hens' meat is cheaper compared to broiler meat; therefore its use in processing is profitable. Parents stock hens of the cross Ross 308 were used for the study. Parent stock hens were fed compound feed. After chilling a hen fillet [musculus pectoralis], hen thighs [musculus biceps] and hen drumsticks [musculus gastrocnemius; musculus fibularis longus] were separated from carcasses. The obtained products were refrigerated at temperature +1+-0.5 deg C. The analyses were performed 1 day after slaughter and on the 5th day of storage. The following parameters were analysed: pH value (3510pH Meter - JENWAY); total protein content (LVS ISO 937:1978); fat content (LVS ISO 1443:1973); colour changes (Color Tec-PCM; software ColorSoft QCW for colour data analysis). The analysed parameters significantly differ in 'white' and 'red' poultry meat, and in various cuts of 'red' meat.
Mostrar más [+] Menos [-]Effects of growing location and variety on free tryptophan and mineral nutrient content in wheat
2009
Lundegaardh, B., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Centre for Sustainable Agriculture | Jastrebova, J., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Zhokhov, S., Swedish University of Agricultural Sciences, Upsala (Sweden). Dept. of Chemistry | Maartensson, A., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Soil and Environment | Oeborn, I., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Plant Production Ecology
Tryptophan (Trp) is an essential amino acid for mammals since they cannot synthesise it. Wheat (Triticum aestivum L.) is a major source of dietary Trp, and wheat high in Trp would thus be very beneficial. This study investigated the impact of location and wheat variety on the content of free Trp and mineral nutrients in wheat grain. Four wheat cultivars from national variety tests on wheat with varying protein contents were selected from seven different locations of Sweden representing different climatic zones and soil contents of trace elements. Grain was analysed for Trp content using reversed phase HPLC. Mineral nutrients were analysed using inductively coupled plasma emission spectrometry. Wheat yield and grain content of nutrients and Trp differed significantly between sites. High N content in grain was correlated with a high content of Cu, Fe and S, and also Ca and Mg. However, it was correlated with a low content of K and Na. Trp content was positively correlated with Na and Zn content and negatively correlated with K/Na and K/(Na+Zn) ratio. The varieties differed in Trp content and the two ratios, but there were no significant differences in yields between the varieties at any location. The results indicated salt stress induction of Trp synthesis, which may protect wheat against salt stress and yield losses.
Mostrar más [+] Menos [-]Transgressive segregation for rain quality traits in the crossings between covered and hull-less barley
2010
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine the transgressive lines of spring barley (Hordeum vulgare L.) for grain quality traits (1000 kernel weight, and content of crude protein, starch and β-glucans) in the six cross combinations between covered and hull-less barley genotypes. The trial was carried out at the State Stende Cereal Breeding Institute during 2007 and 2008. Lines representing either positive or negative transgression were found in each cross combination if compared covered and hull-less lines with their parent varieties. These lines during the two years of investigation exceeded both parents in positive or negative direction by one standard deviation according to any of the four analyzed grain quality traits. Seven positive transgressive lines were observed regarding 1000 kernel weight, and two transgressive genotypes regarding crude protein content within the population of covered barley lines. No line with positive transgression regarding starch and β-glucan content was found within the covered barley population. 27 hull-less lines showed positive transgression regarding any of the four analyzed grain quality traits. The results show that it is possible to increase grain quality of spring barley grain by implementing selection practices.
Mostrar más [+] Menos [-]Characteristic of grain quality for early generation lines in the crossings between covered and hull-less barley
2009
Bleidere, M., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia) | Belicka, I., State Stende Inst. of Cereal Breeding, Dizstende, Talsu reg. (Latvia)
The objectives of the investigation were to determine effect of hull-less gene on grain quality traits (crude protein, starch and β-glucans) and to evaluate the heritability of these traits in the F4 and F5 generations of six crosses between covered and hull-less barley (Hordeum vulgare L.). The trial was carried out at the State Stende Cereal Breeding Institute during the years 2007 and 2008. Mean value, range and the coefficient of variation of traits for covered and hull-less lines within each cross combination were calculated. Heritability of quality traits was estimated as intergeneration correlation (r) and linear regression coefficients (b). The highest intergeneration correlation values were observed for starch content within covered and hull-less barley populations (rF4:F5=0.609 and 0.635 respectively). Moderate intergeneration relationship was observed for crude protein content within covered barley population (r=0.582), and for β-glucans content within hull-less barley population (r=0.593). The regression estimates of heritability were higher for starch content for both covered and hull-less barleys (b=0.549 and 0.703 respectively). Due to effects of genotype and environment interactions the regression estimates of heritability for crude protein and β-glucans content for both covered and hull-less barley were low (b varied from 0.347 to 0.373).
Mostrar más [+] Menos [-]Geographical differences in growth and quality characters of Scots pine Latvian populations
2009
Neimane, U., Latvia Univ. of Agriculture, Jelgava (Latvia)
In the study the growth and stem quality characters of geographically different Latvian Scots pine (Pinus sylvestris L.) populations were evaluated. In various regions of Latvia proportionally to the distribution of Scots pine 21 sample plot was established in 85 to 95 years old pure stands in forest type Myrtillosa growing conditions. In every sample plot 100 trees were evaluated estimating height of the tree, diameter at breast height, stem volume, length and quality of the branch-free stem section, relative branch thickness, branch angle and stem straightness. Pine populations were compared in different seed zones (Western and Eastern), as well as in various regions (Western, Central, South-eastern, North-eastern). In order to describe the geographical differences of populations with help of growth features, tree height was chosen because the relation between height and stem quality features is positive. The populations of the Eastern seed zone substantially overcome the populations of the Western seed zone both in terms of growth features, as well as in stem quality. Substantial are also differences between populations growing in various regions in terms of average height, length and quality of branch-free stem section, relative branch thickness and branch angle, but not stem straightness. Western populations present the lowest growth feature values and stem quality. The height and stem quality features of the North-eastern populations considerably exceeded the features of other regions' populations.
Mostrar más [+] Menos [-]Feeding entire male pigs (Sus scrofa domestica) with high amylose barley cultivar (Hordeum vulgare): impact on boar taint and performance
2009
Chen, G., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Andersson, K., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Animal Nutrition and Management | Andersson, R., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Lundstroem, K., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science | Zamaratskaia, G., Swedish Univ. of Agricultural Sciences, Upsala (Sweden). Dept. of Food Science
The effect of dietary supplement with 17% high-amylose barley (Hordeum vulgare, HAB) 'Karmose' on boar taint was studied on 72 crossbred entire male pigs (Sus scrofa domestica) Swedish Yorkshire dams x Swedish Landrace sires). All pigs were fed the same commercial diet (12.4 MJ metabolised energy (ME) per kg, digestible crude protein (CP) 13.5%) twice a day until the average live weight (LW) in the pen reached 100 +- 11.8 kg. Then, 32 out of 72 pigs received an HAB diet. Half of these pigs received HAB for 14 days and the other half for 28 days. The pigs were slaughtered at an average LW of 122.3 +- 8.6 kg (age 167.2 +- 7.5 days). The HAB diet did not affect performance, carcass and meat quality characteristics, and puberty status, but reduced plasma skatole levels in the pigs (least squares means, 3.6 vs. 2.0 ng mlE-1, P = 0.037). However, this diet failed to reduce skatole, indole and androstenone levels in fat (P is greater than 0.10). Nevertheless, it is desirable to continue investigation of HAB to optimise the feeding procedure to improve efficiency of HAB effect on fat skatole levels. Additionally, validation of a greater amount of HAB in the diet should be performed.
Mostrar más [+] Menos [-]Baking quality and protein composition of emmer wheat landraces
2008
Konvalina, P., University of South Bohemia, Ceske Budejovice (Czech Republic). Faculty of Agriculture | Moudry, J., University of South Bohemia, Ceske Budejovice (Czech Republic). Faculty of Agriculture | Moudry, J. jr., University of South Bohemia, Ceske Budejovice (Czech Republic). Faculty of Agriculture
Emmer wheat, Triticum dicoccum SCHRANK (SCHUEBL), is an old species of cereal which has been traditionally grown in arid areas. The renewed interest in this variety has its origin in favourable quality parameters of emmer wheat grain and a beneficial effect on human organism. This article deals with a study of quality parameters and storage protein composition of 6 varieties of emmer wheat (which have been chosen from the collection of gene bank at the Research institute of Crop Production in Prague-Ruzyně and in České Budějovice). High crude protein content in grain was proved during the trials. Nevertheless, such a characteristic is not suitable for the classical bakery processing (production of leavened products). The analysed genotypes contain more than 10% of high molecular weight glutenins (HMW glutenins), approximately 70% of low molecular weight glutenins + gliadins (LMW glutenins + gliadins), and almost 20% of residual albumins and globulins. Thanks to high share of albumins and globulins, emmer wheat grain is very valuable raw material for the production of healthy diet. The level of stability of storage proteins composition destines the suitability of emmer wheat for organic and low input farming in Less Favoured Areas.
Mostrar más [+] Menos [-]Estimation of productivity and quality of different origin Scots pine in Latvia
2008
Neimane, U., Latvia Univ. of Agriculture, Jelgava (Latvia)
The productivity and quality of different origin Scots pine (Pinus sylvestris L.) progenies at the age of 43 were estimated. The investigation was carried out in 1964. The seeds from six stands growing on mineral and peaty soils in different environmental conditions were sowed. The thinning was done in 2006. The following growth and quality characters were investigated: height of the trees, diameter at breast height, stem volume, standing volume, branch free tree length, branch thickness, branch angle, stem’s straightness. The growth and quality differences of the progenies depending on the seed origin were estimated. The environmental conditions of the Zvirgzde origin place and the test locality were similar. The progeny of the Zvirgzde stand showed superiority in the growth traits (height, diameter, stem volume) as well as good stem quality and high quality of the assortment outcome in thinning. The progeny of the swamp stand (Tireli) had low values in all investigated traits. A significant influence of the environmental conditions of the seeds origin place on the growth and quality of the progeny was found out. Environmental conditions of seeds origin locality and place of forest regeneration have to be similar to avoid decrease of progeny stand’s growth and quality.
Mostrar más [+] Menos [-]The analysis of silver birch (Betula pendula roth.) stands in state and private forests in Latvia
2008
Zalitis, T., Latvia Univ. of Agriculture, Jelgava (Latvia)
In Latvia, birch is the second most widespread tree species; the share of birch is higher in private forests. The Forest Research Inventory that was launched in 2004 provides credible and up-to-date information about all forests of Latvia irrespective of the ownership. The data from first three years’ data base of this Project has been used in the present study. The aim of this study was to analyse birch stands in state and private forests concentrating on different aspects: mixture degree, origin of the stand, productivity and quality of the stand. 735 sample plots were selected from the database for the analysis. The proportion of the birch stands in the private forests was slightly higher than in the state forests. There were more mixed stands in the state forests than in the private ones. The standing volume was higher in the mixed stands while the opposite was true for the current annual volume increment of birch. The main regeneration method in both the state and private birch stands was natural regeneration from seed. Artificial regeneration was used only rarely in the private birch stands. The productivity did not differ significantly between the state and private forests; the same was true for the quality, expressed by the outcome of veneer logs. The stand quality differed significantly among site types, being the highest in the forests on dry mineral soils and the lowest in the forests on drained peat soils.
Mostrar más [+] Menos [-]Evaluation of texture parameters of vacuum and modified atmosphere packed fresh carp (Cyprinus carpio L.)
2008
Kamolina, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dukalska, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Investigations of textural parameters of vacuum, protective gas atmosphere (MAP), and at air ambiance packed fresh carp (Cyprinus carpio L.) farmed in Latvia were carried out. The samples of carp were stored at two different temperatures (0 +- 0.5 and +4 +- 0.5 ºC) applying three different types of packaging – vacuum, MAP, and wrapping at air ambiance. Gas mixture used for MAP consisted of 40% CO2 and 60% N2. Samples were analyzed before packaging (day 0) and after 2, 4, 6, 8, 11 and 14 storage days. Textural parameters – hardness and shear force were evaluated by texture analyzer TA.XT.plus (Stable Micro System Ltd.). Two instrumental methods were applied for evaluation of textural properties. One method was based on compression test, using spherical probe, 25.4 mm in diameter (type P/1S), and measuring the hardness of the fillet and other method was based on cutting the fillet with a blade (type HDP/BSK) and measuring the shear force. The instrumental hardness and shear force of fresh carp fillets decreased during storage time. Texture variables significantly correlate with storage time, respectively, r = -0.723 and r = -0.748, the hardness and shear force. The storage time, temperature and packaging type with probability of 95 % substantially influence the textural parameters of carp fillets (P is less than 0.05).
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