Effect of supplemental vitamin E on the performance of growing-finishing pigs fed stored versus freshly harvested barley and on the storage stability and eating quality of frozen pork

Lihasikojen E-vitamiinin tarve ruokittaessa vastapuidulla ohralla ja rehuun lisätyn E-vitamiinin vaikutus lihan pakastussäilyvyyteen ja syöntilaatuun

Growth of and partitioning between shoot and storage root of carrot in a northern climate

Selostus: Porkkanan kasvu ja biomassan jakautuminen varastojuuren ja verson välillä pohjoisissa oloissa

The effect of storage ageing and spring sprouting of seed tubers on the yield of three potato varieties in the Finnish Lapland : Research Note

Selostus: Siemenmukuloiden varastointiaikaisen lämpökäsittelyn ja kevätidätyksen vaikutus kolmen perunalajikkeen satoon Lapissa

Effect of harvest time on storage loss and sprouting in onion

Selostus: Sadonkorjuuajan vaikutus sipulin varastohävikkiin ja varastoinnin jälkeiseen versomiseen

Food packaging indicators and sensors

Various categories of food packaging indicators namely; VTT, Ageless Eye, Mocon, Åbo Akademi and Impak were selected and incorporated into food trays manufactured at LUT packaging laboratory. Each of these food packaging indicators was used to investigate (visually and qualitatively) the transmission of oxygen through the seal, and tray material, as well as to detect microbial activity within the content of the package. Applications of different methods of gas flushing, content variation and introduction of two distinct levels of oxygen scavengers were employed as treatments to evaluate the packaging performance of the food packaging indicators. Ease of handling of each food packaging indicator was also taken into considerations. Findings showed that for packages, which contained chicken product, the amount of oxygen in the package, measured immediately after the sealing operation on the first day gradually decreased to zero percent by the third day of the storage period. The oxygen level remained at this point throughout the duration of storage for the chicken packages. Besides, level of oxygen in the packages without product continued to increase with the storage time, at moderate rate of 0.1% for 100%N2 and 0.3% for 30%CO2/70%N2 empty packages. More carbon dioxide gas was recorded for packages flushed with 30%CO2/70%N2. Results also revealed that visual analysis of one of the color indicators for example Ageless Eye, conformed to the data derived from the luminescence food-packaging indicator. This shows that packaging operation of the packaging line was considerably stable, and efficient with negligible exception. However, it was found that most of the food packaging indicators investigated in this research study exhibited considerable packaging challenges, such as, reaction with the content of the package (Impak); over sensitivity (Åbo Akademi and Impak); ease of handling problem (Åbo Akademi); and ease of activation problem (VTT indicators). In this study, the strengths and limitations of different indicators were analyzed. This study demonstrates the applicability of various indicators in MAP using chicken package application.

Modification of commercial poly-lactide for extrusion coated food packaging applications

Poly-L-lactide (PLLA) is a widely used sustainable and biodegradable alternative to replace synthetic non-degradable plastic materials in the packaging industry. Conversely, its processing properties are not always optimal, e.g. insufficient melt strength at higher temperatures (necessary in extrusion coating processes). This thesis reports on research to improve properties of commercial PLLA grade (3051D from NatureWorks), to satisfy and extend end-use applications, such as food packaging by blending with modified PLLA. Adjustment of the processability by chain branching of commercial poly-L-lactide initiated by peroxide was evaluated. Several well-defined branched structures with four arms (sPLLA) were synthesized using pentaerythritol as a tetra-functional initiator. Finally, several block copolymers consisting of polyethylene glycol and PLLA (i.e. PEGLA) were produced to obtain a well extruded material with improved heat sealing properties. Reactive extrusion of poly-L-lactide was carried out in the presence of 0.1, 0.3 and 0.5 wt% of various peroxides [tert-butyl-peroxybenzoate (TBPB), 2,5-dimethyl-2,5-(tert-butylperoxy)-hexane (Lupersol 101; LOL1) and benzoyl peroxide (BPO)] at 190C. The peroxide-treated PLLAs showed increased complex viscosity and storage modulus at lower frequencies, indicating the formation of branched/cross linked architectures. The material property changes were dependent on the peroxide, and the used peroxide concentration. Gel fraction analysis showed that the peroxides, afforded different gel contents, and especially 0.5 wt% peroxide, produced both an extremely high molar mass, and a cross linked structure, not perhaps well suited for e.g. further use in a blending step. The thermal behavior was somewhat unexpected as the materials prepared with 0.5 wt% peroxide showed the highest ability for crystallization and cold crystallization, despite substantial cross linking. The peroxide-modified PLLA, i.e. PLLA melt extruded with 0.3 wt% of TBPB and LOL1 and 0.5 wt% BPO was added to linear PLLA in ratios of 5, 15 and 30 wt%. All blends showed increased zero shear viscosity, elastic nature (storage modulus) and shear sensitivity. All blends remained amorphous, though the ability of annealing was improved slightly. Extrusion coating on paperboard was conducted with PLLA, and peroxide-modified PLLA blends (90:10). All blends were processable, but only PLLA with 0.3 wt% of LOL1 afforded a smooth high quality surface with improved line speed. Adhesion levels between fiber and plastic, as well as heat seal performance were marginally reduced compared with pure 3051D. The water vapor transmission measurements (WVTR) of the blends containing LOL1 showed acceptable levels, only slightly lower than for comparable PLLA 3051D. A series of four-arm star-shaped poly-L-lactide (sPLLA) with different branch length was synthesized by ring opening polymerization (ROP) of L-lactide using pentaerythritol as initiator and stannous octoate as catalyst. The star-shaped polymers were further blended with its linear resin and studied for their melt flow and thermal properties. Blends containing 30 wt% of sPLLA with low molecular weight (30 wt%; Mwtotal: 2500 g mol-1 and 15000 g mol-1) showed lower zero shear viscosity and significantly increased shear thinning, while at the same time slightly increased crystallization of the blend. However, the amount of crystallization increased significantly with the higher molecular weight sPLLA, therefore the star-shaped structure may play a role as nucleating agent. PLLA-polyethylene glycol–PLLA triblock copolymers (PEGLA) with different PLLA block length were synthesized and their applicability as blends with linear PLLA (3051D NatureWorks) was investigated with the intention of improving heat-seal and adhesion properties of extrusion-coated paperboard. PLLA-PEG-PLLA was obtained by ring opening polymerization (ROP) of L-lactide using PEG (molecular weight 6000 g mol-1) as an initiator, and stannous octoate as catalyst. The structures of the PEGLAs were characterized by proton nuclear magnetic resonance spectroscopy (1H-NMR). The melt flow and thermal properties of all PEGLAs and their blends were evaluated using dynamic rheology, and differential scanning calorimeter (DSC). All blends containing 30 wt% of PEGLAs showed slightly higher zero shear viscosity, higher shear thinning and increased melt elasticity (based on tan delta). Nevertheless, no significant changes in thermal properties were distinguished. High molecular weight PEGLAs were used in extrusion coating line with 3051D without problems.

The transfer of 137Cs through the soil-plant-sheep food chain in different pasture ecosystems

Selostus: Radiocesiumin kulkeutuminen eri laidunekosysteemien maa-ruoho-lammas -ravintoketjussa

Contribution of livestock to food production in developing countries

Selostus: Kotieläintuotannon osuus kehitysmaiden ruoantuotannosta

The biotechnology of lactic acid bacteria with emphasis on applications in food safety and human health

Selostus: Terveyttä ja ruoan turvallisuutta edistävät maitohappobakteerien biotekniset sovellukset

Web-based reference databases and subject gateways to locate current research information in agricultural and food sciences : a Finnish perspective

Selostus: Maatalous- ja elintarviketieteiden www-pohjaiset viitetietokannat ja aihehakemistot - suomalaisen tiedonetsijän näkökulma