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Dynamics of sugars composition in berries Full text
2010
Boca, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Skrupskis, I.A., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dimins, F., Latvia Univ. of Agriculture, Jelgava (Latvia) | Krasnova, I., Latvian State Inst. of Fruit-Growing, Dobele (Latvia)
The major sugars in six cultivars grown in Latvia are analysed. The content of glucose, fructose and sucrose in strawberry, blackcurrant and redcurrant berries was determined by applying the method of high performance liquid chromatography (HPLC). By using the obtained calibration curves, concentrations of diverse sugars were found in the analyzed samples. Fructose or fruit-sugar, the same as glucose, is mainly the source of energy in the human body though it is decomposed faster and easier than glucose. In all the researched berry cultivars, the amount of fructose was the largest, particularly in blackcurrants. Six strawberry, black- and redcurrant cultivars were evaluated as raw materials for industrial production. The investigation involved chemical and sensory analyses of fresh berries. The results indicate that pH and sugars of fresh berries influence their quality. Furthermore, high level of sugar adversely affects taste stability. Taste degradation in berries is parallel to flavour deterioration. It is concluded that the main emphasis should be given to the properties of fresh berries.
Show more [+] Less [-]Changes in physically-chemical and microbiological parameters of Latvian wild cranberries during convective drying Full text
2010
Dorofejeva, K., Latvia Univ. of Agriculture, Jelgava (Latvia) | Rakcejeva, T., Latvia Univ. of Agriculture, Jelgava (Latvia) | Skudra, L., Latvia Univ. of Agriculture, Jelgava (Latvia) | Dimins, F., Latvia Univ. of Agriculture, Jelgava (Latvia | Kviesis, J., Latvian State Inst. of Fruit-Growing, Dobele (Latvia)
The research focuses on the study of physically-chemical and microbiological parameter changes in Latvian wild cranberries during convective drying. The research was accomplished on fresh Latvian wild cranberries. The following quality parameters were controlled during the experiments: moisture content (oven-dry method), content of vitamin C (LVS EN 14130:2003), content of polyphenol (HPLC), preparation of samples for microbiological testing (LVS EN ISO 7218:2007), enumeration of yeasts and moulds (ISO 21527-2:2008(E)), counting of lactic acid bacteria (LVS ISO 13721:1995), and total plate count (LVS EN ISO 4833:2003A). The research detected the following optimal convective drying parameters of wild cranberries: temperature – +50±1 deg C and drying time – 20.3 hours. The moisture content of dried berries equalled to 9.0±0.1%. The content of vitamin C decreased 1.9 times in wild cranberries dried at the temperature of +50±1 deg C compared with the content of vitamin C in non-dried cranberries and was 13.05 mg 100 gE-1 in dry matter. The results of current experiments show, that the content of such polyphenols as gallic, caffeic, and epicatechin acids decreased 9.70, 9.90, and 11.68 times, respectively, during the treatment at temperatures up to +50±1 deg C compared with the initial content of these compounds in non-dried berries. The drying temperature substantially influences the microflora development in cranberries. It is possible to decrease significantly the content of LAB, mould, and fungi in berries provided the drying temperature of the wild cranberries does not exceed +50±1 deg C, thus prolonging the ready product shelf-life.
Show more [+] Less [-]The changes of the sugars and sorbitol in rowanberries and chokeberries after freezing and thawing Full text
2010
Berna, E., Latvia Univ. of Agriculture, Jelgava (Latvia) | Kampuse, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ozolina, L., Latvia Univ. of Agriculture, Jelgava (Latvia)
Both the rowanberries (Sorbus) and the chokeberries (Aronia) belong to the family Rosaceae. The berries of these cultivars are suitable for production of health-food products. The main components in the dry matter of fruits are carbohydrates, primarily sugars. The aim of this experiment was to determine the content of simple sugars and sorbitol in different fresh rowanberry cultivars and chokeberries and to compare the composition of these compounds after freezing and thawing of berries. The experiments were done in the Customs laboratory of the National Customs Board, State Revenue Service (Latvia). The rowanberries were picked in the Pure Horticultural Research centre, and black chokeberries were obtained from farm 'Ceplīši' (rural municipality of Pure). The contents of dry matter and soluble solids were analyzed in fresh berries, and the contents of sugars and sorbitol were analyzed both in fresh berries and in berries after freezing and thawing of 13 different cultivars of rowanberries and one black chokeberry. For determination of the soluble solids content, the refractometric method was used, and for determination of the glucose, fructose, sucrose and sorbitol content, high performance liquid chromatography was used. The results showed that rowanberries and chokeberries contained 3.24-7.24 g 100 gE-1 of sorbitol which was the dominant compound in all investigated berries. The highest content of sorbitol was found in the wild rowanberries and rowanberries Sorbus aucuparia var. sibirica, but fruits of rowanberry×pear 'Alaya Krupnaya' contained the least content of sorbitol. After freezing and thawing of berries, the content of sugars and sorbitol were decreased by 5-23% with some exclusion.
Show more [+] Less [-]The wood resource availability influencing factors in private forests in Latvia Full text
2010
Tunkele, S., Latvia Univ. of Agriculture, Jelgava (Latvia) | Marcins, J., Latvia Univ. of Agriculture, Jelgava (Latvia)
The forests and woods are the main resources in Latvia. It is vital to understand the amount of wood resources that is being extracted from private forests now and in future in order to be able to predict the forest sector development and growth. The study objective was to identify the key factors in the wood resource availability and assess their role in private forests. In October 2009, the study was conducted to appraise the private forest owners the operational results and find out the future plans in connection to wood resource extraction. In the study a random sampling method was applied, where in the respondent selection the State Forest Service database information was used. In the study the respondent interviewing method CATI with computerized telephone interviews was used. In the selection of affecting factors the expert's method was applied. The study showed that only 25.40% of all private forest owners claimed that there was wood resources extraction in forests, but 29.50% of all private forest owners claimed that they were planning to perform the wood resource extraction in 2010. If the timber selling prices increased by more than 10 LVL per m3 in 2010, then 38% of all respondents claimed that they would increase the wood resource extraction in forests. The study data show that 30% of all private forest owners admit that there are growing stands in the forests, but they can’t be harvested, because road infrastructure is poorly developed or there are no roads in the forests.
Show more [+] Less [-]Estimation of forest parameters using the non-parametric techniques and satellite images at compartment level Full text
2010
Jonikavicius, D., Lithuanian Univ. of Agriculture, Akademija, Kauno reg. (Lithuania) | Mozgeris, G., Lithuanian Univ. of Agriculture, Akademija, Kauno reg. (Lithuania)
This paper discusses the use of medium resolution Landsat TM satellite images to support conventional approaches of Lithuanian forest inventory practices. Estimation accuracies achieved using just field measured sample plots, Landsat TM satellite images and two non-parametric k-nearest neighbour and most similar neighbour estimators were studied at a level of compartments. 19 mature forest areas, prepared for final felling with GPS measured borders and all trees callipered, were used for validation. Notably higher estimation accuracies were achieved using field sample plots distributed through the whole forest area studied than just ones located on mature forest stands. The root mean square deviations in estimating compartment-wise volume of growing stock per 1 ha was around 27-28% if the best variant of estimation approach was used. Possible influence of the accuracy in locating the borders of validation areas on the estimations is discussed in the paper, too.
Show more [+] Less [-]Impact of amelioration system renovation on the growth of mature forest stands Full text
2010
Zalitis, T., Latvian State Forest Research Inst. Silava, Salaspils (Latvia) | Libiete-Zalite, Z., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
Both forestry theory and practice have proved that amelioration favours the growth of forest stands significantly. The growing stock increases even 10 times, if the amelioration system is well-functioning. Joint Stock Company Latvia State Forests that is managing half of forests in Latvia has started renovation of old amelioration systems aiming to improve the productivity of state owned forests in Latvia. In order to evaluate the impact of the renovation of the old amelioration systems, a tree ring width in 7 pine stands, 5 spruce stands and 3 birch stands was analysed. This study shows that the renovation itself has not affected the productivity of mature pine, spruce and birch significantly 3-4 years after the renovation. Authors have come to a conclusion that the reason for that could be too short observation period or particularities of a stand structure and age.
Show more [+] Less [-]Territorial organisation of game management in Latvia Full text
2010
Baumanis, J., Latvia Univ. of Agriculture, Jelgava (Latvia) | Ozolins, J., Latvian State Forest Research Inst. Silava, Salaspils (Latvia)
The number of the most important game animals of artiodactyla species (moose, red deer, roe deer, wild boar) has been increasing in Latvia during the last 10 years. At the same time, the number of hunting districts where the census of these game animals is taken is also increasing, whereas the average area of the districts is diminishing. The studies show that at present the area of many hunting districts is notably smaller than the individual territory inhabited by these species. This particular study aims at establishing whether there is a relationship between the area of a hunting district on which a census is taken and the number of animals counted, as well as whether the number of animals is really increasing or the increase in the number is attributed to an increase in the census unit number. It was established that in respect of the four species there is a significant correlation between the area of the hunting district and the density of animals in the district. The number of moose and red deer may be assessed more objectively in the districts with an area exceeding 5,000 hectares. The census of roe deer and wild boars is notably influenced by the area of the territory where the census is taken, but the analysis does not explicitly show whether the number of roe deer and wild boars is under-assessed in large districts or over-assessed in the small ones.
Show more [+] Less [-]The beef chain in Costa Rica: Identifying critical issues for promoting its modernization, efficiency and competitiveness Full text
2008
Holmann, Federico J. | Rivas Ríos, Libardo | Pérez, E. | Castro, C. | Schuetz, P. | Rodríguez, J.
The objectives of this study were to (1) describe the economic agents of the chain and their commercial and legal relationships; (2) identify the articulations between links, technological levels, indicators of efficiency, installed capacity (scale), and degrees of occupation; (3) characterize and estimate the costing and pricing structures, and the generation of value in different links of the chain; (4) identify those critical costs that can be modified through technological interventions, policy, or other activity; (5) determine the biological and economic risk factors throughout the chain; and (6) develop a methodology to identify and estimate the costs and benefits in each segment and evaluate the generation of value throughout the beef chain. Data at the farm level was obtained from a national livestock survey (CORFOGA 2005b), which provided data on production systems, inventories, productivity, culling, and labor. In addition, surveys were carried out in different segments: (1) auction houses, (2) slaughterhouses, (3) butcher shops, and (4) supermarkets. The aim of these surveys was to describe behavior, determine risks and costs, and identify problems. The weak dynamics of livestock production in Costa Rica are reflected in unsatisfactory productivity indicators. The annual gross income was estimated as US$44/ha for cow-calf operations, $126/ha for dual purpose (including income from milk sales), and $135/ha for fattening activities. Such income rates are considered extremely low, if one uses as reference the commercial value of land allocated to livestock production (ranging between $1000 and $2000/ha). The aforementioned biological inefficiencies, combined with high land costs, impede the recovery of opportunity costs for the capital invested in land, thus making beef production uncompetitive. The cow-calf operation, with its low productivity, remunerates family labor with wages below the legal minimum. On the assumption that the only cash cost is that of labor, cow-calf farms pay family workers at a wage that is equivalent to 60% of the legal minimum. Auctions present relatively good profits per event. However, when these profits are analyzed on a calendar-day basis, they are unattractive because of the low use of installed capacity. One strategy that would usefully improve the efficiency of the auction system in Costa Rica is its integration to reduce the number of fixed operational costs or encourage sharing of these houses so that administrative and operational personnel are rotated among the several existing auctions, taking advantage of the fact that they differ in their days of operation. This scheme would help reduce fixed costs and the commission collected without affecting profits, thus improving efficiency in this link of the chain. However, this option is not easy to implement, as auctions are run by private operators, whose various interests do not always coincide. The industrial sector formed by rural and industrial slaughterhouses shows a low occupation of installed capacity, resulting in high operational costs and low labor efficiency. The total operational costs of slaughtering and dressing are estimated as being between US$32 and $66 per animal. If the estimated unit costs are compared with the rates charged per slaughtered animal (between $15 and $23), then we have to conclude that rural slaughterhouses work at a loss and that industrial slaughterhouses cover their operational costs with processing services and the very small profit margins from sales of byproducts. The best performance in terms of efficiency and profitability is found in the retail sector of butchers and supermarkets. The rate of profits, expressed as the fraction of the final price paid by the consumer that remains in the butcher’s hands as remuneration of his work, ranges widely between 3% and 40%, with an average of 32%. If these profit rates are compared with those of other retail businesses, which are about 8%, then this type of activity presents excellent profit margins with relatively low risk. If, in addition, we take into account that this sector also offers the consumer a broad range of meat cuts from other animals such as pork and chicken, and processed meats, then profit margins are still higher. The value generated throughout the chain, as a percentage of the final value of the young steer at retail price according to activity, is distributed as follows: fattener (34%), retailer (33%), breeder (19%), slaughterhouse (7%), transporter (6%), and auction house (1%). As observed, the distribution of value throughout the beef chain is totally inequitable and incongruent with the level of individual risk confronted by the actors who form it. The inequity observed in the distribution of added value reflects a clear dominant position in the market of some actors of the chain, which enables them to capture a very high fraction of the profits. The value generated in the chain, adjusted for operational time in each link, ranges between US$0.28/animal per day for the breeder and $45.85/animal per day for the butcher. Thus, the highest proportion of the total added value concentrates on the final link of the chain. The butcher or supermarket obtains, on the basis of one animal in the same unit of time, 164 times more value that the breeder located in the first link of the chain. The latter has to confront biological and economic risks not covered by insurance policies, whereas retailers may mitigate risks through insurance policies for their raw materials, equipment, and infrastructure. The competitiveness of the beef chain is the aggregate of the efficiency and productivity of all the links that form it. In a situation where, in the final segment, the demand for beef is low and weakly dynamic, then economic signs of modernization and the technological change it promotes, are not being generated in other components of the chain, particularly in the first link of production. This, in turn, results in a vicious cycle, generating low productivity and lack of competitiveness. To promote technological change, efficiency, and competitiveness in the value chain for beef in Costa Rica, we propose the following six recommendations: 1. That successful experiences of other chains such as that of poultry be analyzed and learned from to identify strategies that would increase the efficiency of the beef chain as a whole. 2. That strategies for promoting the milk production of breeding cows be developed to increase family income, as remuneration of labor is currently below the minimum wage. This option would be viable only in localities where a milk market exists. That livestock producer funds [a livestock producer fund consists of granting livestock in company to produce meat, provided that the producer concerned has adequate pastures for this purpose on his farm] be created as mechanisms to develop social capital, reduce transaction costs, and help improve the chain’s productivity and profitability. These organizations would bring together the different classes of the chain and favor synergies in the interaction of public and private actors. 3. That incentives be created to promote the large-scale adoption of already available improved forage species, as most of the problem of low livestock productivity originates in poor and deficient feed. This strategy would emphasize feeding during dry seasons, thereby minimizing seasonal weight losses in the national herd and improving the profitability of farms. 4. That a carcass classification system be established, based on quality and price that would permit differentiating supplies for different segments of the market. 5. That consumer education be promoted on the health benefits of beef, forms of preparation, and differentiating between cuts, uses, and qualities of beef products.
Show more [+] Less [-]Characterization of smallholder pig production systems in Uganda: Constraints and opportunities for engaging with market systems Full text
2014
Ouma, Emily A. | Dione, Michel M. | Lule, Peter M. | Roesel, Kristina | Pezo, Danilo A.
Pig production has increasingly become an important activity, especially among smallholder farmers in Uganda in the past three decades as evidenced by a dramatic rise in pig population from 0.19 to 3.2 million. This is linked to the rise in demand for pork due to changes in preferences. Per capita consumption of pork has been estimated at 3.4 kg/person/year representing a ten-fold increase in the last 30 years. Pigs are important assets for the poor smallholders in Uganda generating income for meeting planned and emergency household financial needs. Despite its importance, the smallholder pig systems are faced with a number of productivity and market related constraints ranging from diseases, poor nutrition and poorly organized markets. Strong growth opportunities to improve smallholder pig systems exist if the constraints are minimized. However the constraints and opportunities vary among smallholder producers as they are not a homogenous group and are affected by various factors. This paper applies a cluster analysis to characterize smallholder pig production systems into typologies in three districts in Uganda by utilizing village level data from 35 villages. The paper further explores the constraints and opportunities for the different typologies to engage with output and input market systems. The paper concludes that different interventions are necessary to improve market linkages with the smallholder pig production systems due to their varying differences in terms of farmers’ cooperative involvement, institutional linkages and intensification related indicators.
Show more [+] Less [-]Breeding scheme based on community-based participatory analysis of local breeding practices, objectives and constraints for goats around Dire Dawa, Ethiopia Full text
2013
Gebreyesus, G. | Haile, Aynalem | Dessie, Tadelle
This study was conducted in the rural kebeles around Dire Dawa for designing a simple, yet, feasible breeding scheme in the context of community-based management of animal genetic resources. Range of participatory rural appraisal tools, including focal group discussions and participatory mappings, were employed to study the local community’s Indigenous knowledge and practices in managing the goat gene pool. The breeding objective and local trait preferences were defined in a participatory manner through own-flock ranking experiments. The community generally practices selective pure breeding where by the own flock and flocks in the neighbourhood were the units of selection for bucks. There are social regulations in the community against sale of breeding does outside the community while encouraging communal use of outstanding breeding males. Goats are kept for multifaceted purposes ranging from products like milk, meat and live-sale to functions in socio-cultural, financial and ritual state of affairs. The breeding objective is to ensure improved milk production, through increased daily yield per doe and increased fertility per flock, and increased net income per flock, through increased number of marketable animals. Traditional criteria such as conformation, behaviour and adaptation were as important as most “production” traits in selecting breeding animals. The breeding goal traits considered were, accordingly, milk production, conformation and reproductive traits. Based on these findings, village breeding schemes, where-by flocks and breeding groups in a village are taken as focal points, is recommended as way forward in genetic improvement. The framework for a feasible implementation of such genetic improvement scheme is outlined based on the rationale of utilizing available social regulations, indigenous knowledge and traditional systems of breeding as well as future market prospects.
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