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Environmental sustainability aspects in short food supply chains: The views of organic farmers and consumers
2023
Ušča, Maija | Aļeksējeva, Lāsma
Globally, food systems are the most significant cause of environmental change; therefore, efforts to create more environmentally sustainable food systems are presented. One of the directions is strengthening the local actors and short food supply chains. Simultaneously, changes in farming systems are needed, and organic agriculture is one of the ways to make food systems more environmentally sustainable. Despite the abundance of research on the environmental consciousness of consumers in short food supply chains, the question is raised whether local food chain farmers are also committed to environmental sustainability. Therefore, this paper aims to explore the importance of environmental sustainability to organic short food supply chain actors. More specifically, the research depicts the views of organic farmers and consumers and their relation to the actual environmental sustainability of short food supply chains. During the research, a specific short food supply chain – a direct purchasing network – was explored. A qualitative approach was applied to reach the aim. Thus, in-depth interviews and observations were used as a research method. The research results demonstrated the views of farmers and consumers of the specific network regarding environmental sustainability aspects in the network. In the research, such environmental aspects as the circularity of resources, biodiversity, chemicals in the environment, seasonality and locality of diets, and the distance (food miles) were admitted as crucial ones by the specific short food supply chain actors. The differences in opinions of consumers and farmers emerged when thinking about the scale of their views.
اظهر المزيد [+] اقل [-]Barriers to agricultural products diversification: An empirical analysis from lotus farming in Central Vietnam
2023
Nguyen, Chung Van | Abwao, Martin | Nguyen, Hue Van | Hoang, Ha Dung
Poverty alleviation, employment creation, environmental conservation and income augmentation can be transformed based on agricultural diversification. Lotus farming is considered as a solution to improve income and livelihood for smallholder farmers. Many different products and values can be explored from lotus farming including lotus flower, lotus root, lotus seed, lotus fibre, as well as combining ecotourism. But many barriers are preventing the lotus products diversification of lotus growers. This study will provide a better understanding of lotus farming and explore the barriers to lotus products diversification and causes of these barriers. Phong Dien district, central Vietnam was selected as a case study. The qualitative research was applied through 54 semi-structured interviews including lotus growers, lotus buyers and officers of local government, as well as one focus-group discussion, observation method and secondary data from statistical data and reports were also conducted. The research findings indicated that there is a big gap between lotus products diversification of lotus growers and available lotus products on the market. Lotus growers only grow and sell raw products, of which, fresh unshelled lotus seed is the main product. Lack of knowledge, worries on loss, lack of market and market information, lack of labour and machines and traditional production habits are main determinants of the barriers. Characteristics of lotus seed, high production and monopoly of collectors are different features in barriers to lotus product diversification compared to other crop diversification.
اظهر المزيد [+] اقل [-]Isolation and characterisation of pigments from pigment-producing microorganisms isolated from environment and their antibacterial activity
2023
Deveikaite, Goda | Zvirdauskiene, Renata
In the food industry, there is always a demand for food products which are colourful, have an attractive appearance, and also have nutritional and health-enhancing properties to attract the attention of consumers. Synthetic pigments are widely used in the global market, however, they can cause many side effects such as hyperallergenicity, carcinogenicity and other toxicological problems. Recent studies have revealed that microorganisms are an abundant source of natural colours that allow the industrial production of safe, environmentally friendly biodegradable pigments. The aim of the work was to isolate pigmented microorganisms from environmental samples, select fermentation conditions, isolate pigments from microorganisms and check their antimicrobial activity. Pigments have been isolated from various sources such as soil, food waste, flour, etc. Growth parameters of pigment-producing microorganisms such as growth temperature, pH, and tryptone and NaCl concentration in the medium were optimised to evaluate pigment production. After fermentation, five types of pigments were isolated by cell lysis with an ultrasonic bath and solvent extraction. The antimicrobial activity of the extracted pigments was investigated. During the study, the optimal conditions for the growth of microorganisms were determined: temperature of 30 °C, pH of 7, concentration of 3% tryptone and 6% NaCl in the culture medium. Glycerol was found as an additional carbon source, which had a positive effect on pigments production. The results of the antibacterial effect of the extracted pigments showed that P. aeruginosa was the most sensitive to the effect of the pigments. The pink-red pigment showed the highest antimicrobial activity against the tested pathogenic bacteria.
اظهر المزيد [+] اقل [-]Retrospective analysis of 81 feline lymphoma cases diagnosed in surgical biopsies in Latvia (2011–2020)
2023
Geine-Romanova, Lilija | Matise-Van Houtan, Ilze
Lymphoma (also known as lymphosarcoma) is a malignant tumour accounting for 20–30% of all neoplasms in cats. There have been no previous studies summarizing trends and characteristics of feline lymphoma in Latvia. The aim of this retrospective study was to determine the prevalence and characteristics of feline lymphoma cases among biopsy submissions to a private veterinary pathology service in Latvia. Data were retrieved by selecting records from Latvian cats diagnosed with lymphoma between 2011 and 2020, including signalment, clinical history, and type of lymphoma (anatomical classification, cellular morphology). In the 10-year period, the mean prevalence of lymphoma among feline biopsy submissions was 4.8% (range 1.9–7.2) without upwards trend. Lymphoma was most common in mixed breed (67%), middle-aged (median 8 years) cats with a slight male predominance (56%). Among purebred cats the development of lymphomas was observed at an earlier age. The predominant anatomical type was alimentary lymphoma (53%) followed by extranodal (38%) and multicentric (7%) lymphoma. Majority of alimentary lymphomas were in the small intestine (73%) and 88% of gastrointestinal lymphomas were transmural with remaining cases limited to mucosa (12%). Overall, representation of anatomical types of lymphoma in Latvian cats was similar to those reported elsewhere; however, the subset of intestinal mucosal lymphoma in our study was underrepresented. This finding suggests that until 2021 intestinal mucosal lymphoma was uncommonly considered as a differential diagnosis for cats with enteritis therefore biopsies from such cats were not performed. This study will help Latvian veterinarians to improve diagnostic work-up of lymphoma cases.
اظهر المزيد [+] اقل [-]Effect of coating on physico-chemical characteristics of puffed wheat grains
2023
Konkubaeva, Nurzat | Juhnevica-Radenkova, Karina | Radenkovs, Vitalijs | Galoburda, Ruta
Durum wheat (Triticum turgidum) is used for the production of various ready-to-eat products such as breakfast cereals, puffed grains, and extruded products. Technological processes of grain processing and the addition of different ingredients cause changes in the physical and chemical properties of the product, which give puffed grains a unique porous structure and change their nutritional value. This study aimed to evaluate the effect of coating on the physico-chemical characteristics of puffed wheat grains depending on the coating material. The study revealed that the application of coating increased dry matter and thousand-kernel weight (TKW). Water activity decreased in puffed grain without coating (BZ), and puffed grain with whey powder (MC) compared to wheat grain. The reduction in the moisture content increased the crispiness of product. Application of coating led to a decrease in the hardness of both MC and puffed wheat grain with vanillin and sugar (BV). Applying additives to the product’s surface led to a decrease in the water absorption index (WAI). The water solubility index (WSI) increased in the MC and BV samples. Samples BZ, BV and MC had higher L* (lightness) values than wheat grains because the puffing process expanded the cells, confirmed by scanning electron microscopy, and caused starch gelatinisation. The a* (redness) value of wheat was greater than that of BZ, BV and MC, which may be due to the partial removal of the outer layer of wheat grains. The milled samples of BZ, BV and MC were slightly darker, having lower L* values, compared to unprocessed wheat grain.
اظهر المزيد [+] اقل [-]Impact of fungicide treatment schemes on the severity of leaf blotches in winter wheat
2023
Švarta, Agrita | Bimšteine, Gunita | Bankina, Biruta | Kaņeps, Jānis | Gaile, Zinta
The common control method of leaf blotches is the application of fungicides; however, the results of trials are inconsistent. The aim of the present study was to evaluate the impact of the fungicide treatment intensity on the severity of leaf blotches and to assess the correlation between the development of diseases and winter wheat (Triticum aestivum) yield in 2018–2021. The development of diseases was evaluated regularly. In this study, the severity of leaf blotches at the medium milk ripening (GS 75–77) was used. Tan spot dominated in 2018, 2019, and 2021, but Septoria tritici blotch dominated in 2020. Fungicides significantly decreased the severity of tan spot and Septoria tritici blotch, but the efficacy of used fungicide treatment schemes differed during trial years – it was more pronounced under higher pressures of leaf blotches. In the year with a high severity of Septoria tritici blotch, the best efficacy was obtained when fungicide was used two times (at GS 32–33 and GS 55–59), but for tan spot – when the dose of fungicide was done in two or three applications. Usage of fungicides increased wheat yield only under high pressure of diseases. A strong significant correlation between the severity of Septoria tritici blotch at GS 75–77 and grain yields was established only in 2020, when the severity of the disease was higher.
اظهر المزيد [+] اقل [-]Fatty acid composition of different breed goat milk
2023
Marcinkoniene, Liga | Ciprovica, Inga
The chemical composition of goat milk, especially fatty acid profile is recently renewed due to the role of monosaturated and polyunsaturated fatty acids in human nutrition. These nutrients are important to analyse in connection with the different breeds receiving the same breeding and feed. The aim of this study was to analyse goat milk fatty acid profile in relation to different breeds. Specimens for fatty acid analyses were collected from individual animals of breeds like Latvian Native (n=5), Saanen (n=5), and crossbreeds (n=5). Bulk milk samples (n=5) were also taken for milk quality testing and fatty acid range determination. Fat content was analysed according to ISO 1211:2011 and fatty acids were measured with the chromatographic method. Protein, lactose, casein and urea concentration was analysed according to ISO 13366-2:2007 and somatic cell count to ISO 9622/IDF141:2013.The highest fat concentration was determined in crossbreed milk samples (3.81 g 100 gE−1) and the lowest (2.96g 100 gE−1) in the Latvian Native breed goat milk samples. The highest butyric acid (0.12 g 100 gE−1) and caproic acid (0.12 g 100 gE−1) concentration was established in Saanen goat milk samples. Compared to other breeds, the milk of the Latvian Native breed goats is characterised by a higher capric acid (0.20 g 100 gE−1) concentration, while a higher concentration of total unsaturated and monounsaturated fatty acids was detected in the samples of crossbreed goat milk. The average fatty acid composition of bulk milk samples was 68% for saturated fatty acids, 23% for monosaturated fatty acids and 4.3% for polyunsaturated fatty acids. In analysed goat milk samples, fatty acids showed the characteristic fatty acid profile of goat milk.
اظهر المزيد [+] اقل [-]Evaluation of fatty acid composition in amaranth pasta developed for a vegan diet
2023
Marisheva, Alla | Beitane, Ilze
Consumers’ growing demand for vegan products creates a need for new nutrient-dense products. Amaranth seeds are characterised as a nutritious product due to the content of proteins, fats, etc. Considering the high-quality fats and their amount in amaranth seeds, the aim of this study was to analyse the profile of fatty acids in amaranth pasta which was developed for a vegan diet. Seven samples: amaranth, amaranth-oat, and amaranth-buckwheat pasta in different ratios, were analysed in the study. The preparation of samples for analysis was carried out according to LVS EN ISO 6498:2012; fatty acid composition was determined using thug/MS analytic method. The highest total fat content was determined in the amaranth pasta – 5453.62 mg 100 gE−1 of product, followed by the amaranth-oat pasta (85%/15%) – 4988.14 mg 100 gE−1 of product and amaranth-oat pasta (70%/30%) – 4772.93 mg 100 gE−1 of product. In the developed pasta samples, over 70% of total fat was unsaturated fatty acids and more than one-third of total fat was PUFA. The highest PUFA/SFA ratio was determined for amaranth-oat pasta (70%/30%), amaranth-buckwheat pasta (85%/15%), and amaranth-buckwheat pasta (70%/30%). Quantitatively, the essential fatty acids were oleic acid, linoleic acid, and palmitic acid. The triterpene squalene was detected with a probability of 90% in all amaranth, amaranth-oat, and amaranth-buckwheat pasta samples. The developed pasta for a vegan diet contains good-quality fat.
اظهر المزيد [+] اقل [-]Studies on potential pests of Japanese quince (Chaenomeles japonica (Thunb.) Lindl. ex Spach) in Latvia
2023
Gailis, Jānis | Jakobija, Inta | Jakobsone, Edīte | Ozoliņa-Pole, Laura | Rancāne, Regīna | Salmane, Ineta
The objective of this research was to study potential pests of Japanese quince (Chaenomeles japonica) plantations in Latvia. Studies were carried out in eight plantations during 2017–2019. Major pests that would regularly cause significant yield losses for this plant were not observed. Black-veined white (Aporia crataegi) was considered a local pest, mass outbreaks of which can occur in individual plantations and cause significant losses of plant foliage. Four species were considered minor pests: garden chafer (Phyllopertha horticola), yellow-banded weevil (Chlorophanus viridis), silver-green weevil (Phyllobius argentatus) and copse snail (Arianta arbustorum); they are also pests of plant foliage. The European red spider mite (Panonychus ulmi) was not considered as a pest of Japanese quince. A small population was observed in summers only in one plantation, which was located next to a heavily infested orchard. Overwintering eggs were not found on the plants in any year, and we concluded that the species was an accidental immigrant in this plantation. No aphid (Aphididae) colonies were observed on the quince plants. Monitoring and evaluation of potential harmfulness of four tortrix moths – large fruit-tree tortrix (Archips podana), rose tortrix (Archips rosana), codling moth (Cydia pomonella) and holly tortrix (Rhopobota naevana) – was done. It was concluded that rose tortrix is a minor fruit pest, but the other three species were not yet considered pests of Japanese quince. Significant pests of quince flowers and fruits were not detected in our study.
اظهر المزيد [+] اقل [-]Sound absorption properties of the patented wood, lightweight stabilised blockboard
2023
Roziņš, Rihards | Brencis, Raitis | Spulle, Uldis | Spulle-Meiere, Ivanda
It is well known that wood tends to shrink and swell as the relative humidity of the air changes. There have been, and still are, attempts to make dimensionally stable wood panels such as Dendrolight®. The physical-mechanical, operational, including acoustic, properties of this material have been significantly improved compared to traditional wood-based panels. However, the production of this material requires very specific processing equipment and a large energy investment. The developers of this material in Latvia invented and patented wood, Lightweight Stabilised Blockboard (LSB). In order for this material to be used in the production of various products, it is necessary to clarify its characteristic, technological, as well as operational properties. The study gathers information about the sound absorption properties of various natural and wood materials, characteristics, and the sound absorption of the studied material at different sound frequencies. The reviewed sources of information indicate that nowadays there are still problems in sound conduction and absorption and isolation issues are being addressed in building acoustics. The production of samples and the determination of sound absorption were carried out using a developed methodology developed in accordance with regulatory requirements. The data obtained in the practical study were compared with the relevant indicators of the Dendrolight® and wood-based panels used for building structures and to determine their compliance with the requirements set forth in the standards ISO 10534-2 and ISO 11654. Research data show that LSB corresponds to E sound absorption class in some of the investigated frequencies.
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