In the late 1980s the demands for a more ecological life style and sustainability set off intense research for methods to analyse and assess the environmental impact of products and systems. The methodology crystallizing from this research is called life cycle assessment (LCA). This paper presents the concept, methodology, applications and present status of LCA. LCA as applied to food production systems is discussed in terms of needs, special demands on methodology, the studies that have been performed and ongoing activities. © 1994.

Chitosans having degrees of N-acetylation, FA, ranging from 0 to 0·6, were randomly degraded to different molecular weights and studied by multi angle static laser light scattering (LLS). Under the given experimental conditions, negative second virial coefficients of the solutions, A?2, revealed the presence of concentration dependent aggregates. Attempts to remove the aggregates, or to influence the aggregation behavior, were made by ultracentrifugation and extensive filtering of the solutions. Modification of the solvent conditions such as pH, ionic strength and temperature were carried out, and chitosan solutions were digested with an acidic proteinase. Non-degraded samples and chitosans prepared by both heterogeneous and homogeneous N-deacetylation of chitin were also studied. In all cases, the negative A?2 remained. However, it was observed that ultracentrifugation and filtering of the solutions decreased the measured molecular weights and radii of gyration, indicating that some of the material of high molecular weight and size could be removed by ultracentrifugation and filtration. The chemical nature of the physical basis of the molecular association was not revealed. Nevertheless, by the use of gel permeation chromatography coupled to an on-line low angle laser light scattering instrument and a differential refractive index concentration detector (HPSEC-LALLS-RI), a bimodal molecular weight distribution was observed in which about 5% of the sample had a very high molecular weight. These results coupled with the positive virial coefficients obtained earlier from osmotic pressure measurements suggest that a small fraction of the chitosan is aggregated to high molecular weight material, probably following a closed association model. Electron microscopy revealed the presence of some supramolecular structures. The positive second virial coefficients obtained earlier from osmometry are in harmony with these findings. The results demonstrate the occurrence of reversible aggregation in chitosan solutions. Static laser light scattering therefore cannot readily be used to determine molecular weights and sizes of chitosans under these conditions. It was not possible to correlate the extent of aggregation with the chemical composition of the chitosans. © 1994.

A seminested polymerase chain reaction (PCR)-based diagnostic assay was evaluated for detection and verification of Neisseria meningitidis, Haemophilus influenzae, Streptococcus pneumoniae, Steptococcus agalactiae and Listeria monocytogenes in cerebrospinal fluid (CSF) and other biological samples. A general bacterial amplicon from the 16S rRNA gene was amplified in a first step, and species-specific regions in a second. The detection level was 4 fg DNA/reaction, corresponding to about one bacterial genome per reaction tube. Sample preparations (Dynabeads DNA DIRECT kit) were assayed from 140 bacterial strains suspended in saline. In CSF the detection level for bacteria was 103 CFU ml-1 for N. meningitidis, H. influenzae and S. pneumoniae, 104 CFU ml-1 for Escherichia coli and 105 CFU ml-1 for S. agalactiae and L. monocytogenes. The detection levels for these bacteria were the same in the other tested biological samples, like blood with or without culture media. Clinical CSF samples were evaluated from 71 patients with proven bacterial meningitis, as were 61 CSF samples from individuals without bacterial meningitis. The diagnostic sensitivity of the assay in detecting bacteria in general was 0.97, and for the specific species in the clinical CSF samples 0.87-0.94. The specificity was 1.0 for detecting bacteria in general. Some cross-reactions were noted within the streptococcus group. The PCR results were verified by banding patterns of HaeIII digested PCR products.

A pilot plant process simulation of dry and wet hydrothermic treatment of oats was performed in order to study the effect of the different process steps on lipase activity and the storage stability of the fat phase. A comparison was made between oats that had passed through a dry kiln treatment prior to steam preparation and oats that had only been steam-treated. Samples were taken after step in the process as well as during storage at +30°C for up to 44 weeks. The lipase activity disappeared after steam preparation, but not after the dry-heat treatment used in this process experiment. The fat phase was analysed with regard to the amount of free fatty acids (FFA) and the content of individual fatty acids. The initial content of FFA was about 8-9%. The hydrolysis of fat, giving an increase in the amount of FFA, took place in all the stored samples, but was much more pronounced in the samples that had not undergone dry- heat treatment. In the dry-heat-treated samples, the FFA concentration reached a maximum at 13-15% after 16 weeks of storage. In the samples that had not been dry- heat-treated, the FFA reached over 30% in whole oat grains after 16 weeks of storage and continued to increased to over 40% after 30 weeks of storage. In the flour the FFA concentration was lower than in whole grains. Unexpectedly, lipolysis in this case was more pronounced in the whole kernels than in the flour samples. Lipolysis was not related to the measured remaining lipase activity. Head-space analyses of hexanal indicated that the formation of volatile lipid oxidation products was dependent on the process design, but the hexanal concentration was not related to the amount of FFA.

The food and drink (F & D) sector in Europe ranks low in innovation and the European F & D industry has been losing importance in the global market. The food professionals, i.e., food scientists and technologists (FSTs), may not be meeting the varied demands of the sector. Here, education, experience and skills of current FSTs were identified and compared geographic regions and employment areas. Between 2009 and 2012, 287 questionnaires representing over 4000 FSTs were collected from employers in 16 countries. Analyses showed that more than 80% of FSTs have a university degree; but only in Industry in the Central European region are most degrees in food science/technology. More than half of FSTs, and almost 60% in the South, have less than 10 years' experience. The most common FST job title is Quality Manager, but with several variations based on region and employment area. Among skills, the most common is Communicating; found in over 90% of FSTs in all regions and employment areas. Food Safety is the most common of the food sector-specific skills, present in more than 75% of FSTs, yet there are differences in food sector skills based on employment area. Overall, these data suggest similarities among currently employed food professionals throughout Europe; they are young and highly educated, but also differences, especially in their food sector-specific skills. An understanding of the current FST should contribute to the improvement of FST training and thus benefit the European food sector.

A double-blind cross-over study was conducted during two 3-week periods. Two series of seafood products were prepared, one containing n-3 fatty acids derived from fish oil triglyceride concentrate and one containing n-6 rich sunflower oil in identical amounts. These products were added to the subjects' ordinary diet. After a wash-out period of at least 4 weeks they switched over to the other diet. Twenty-three subjects with borderline high blood lipids participated, five women and 19 men, with a mean age of 48 ± 9 years. The inclusion of the n-3 enriched seafood products in the diet caused significant reductions of serum triglycerides (25%) and of the systolic blood pressure of 3.7%. An increase in the proportion of long-chain fatty acids in the serum phospholipids after the fish oil period was pronounced. Positive effects were seen on insulin and free fatty acid concentrations with a reduction of 37% of free fatty acids on the fish oil period and of 18.6% of serum insulin concentration. An increase of malondialdehyde concentration in plasma by 21% was seen during the fish oil period. The positive effects on the serum triglyceride and blood pressure are interesting from the viewpoint of public health with regard to the risk of the cardiovascular disease.

The formation of volatile compounds in potato slices was analyzed by means of gas Chromatographie headspace analysis. The experimental variables selected for the treatment of the potato slices were chosen to simulate the conditions during the first stages of an "add-back type" of process for production of potato granules. The potato slices (2 cm thick) were exposed to air of low temperature (4°C) and water at blanching temperature (76°C). Both the surface and the middle of each slice were analyzed for volatile compounds. Hexanal was the most abundant aldehyde formed. At the elevated temperature, in particular, there was an obvious formation of hexanal. After 15 min of blanching, the amount of hexanal was higher in the middle of the slices than at the surface. This difference in hexanal concentration was probably due both to the leakage of hexanal into the blanching water from the surfaces of the potato slices, and to the inac-tivation of lipoxygenase at the surfaces which prevented further oxidation during the subsequent chilling period. The hexanal formation indicates that lipid oxidation occurs during the process. The formation of other volatile compounds also is discussed. © 1990 American Oil Chemists' Society.

In this article, we describe how starch functionality can be explained in terms of structure. The behaviour of different types of starches is demonstrated by showing how the microstructure of potato and wheat starch is related to their rheological properties. The results illustrate the structural importance of amylose and amylopectin. The microstructure of a completely new type of genetically engineered potato amylopectin starch is presented for the first time.

Lipid hydrolysis and oxidation were evaluated by multivariate statistical methods in farmed rainbow trout (Oncorhynchus mykiss). The trout were acclimatized at 5 or 12°C and then frozen as fillets and stored at -15°C for up to 34 weeks. Results from analyses of lipid hydrolysis and lipid oxidation during frozen storage of light and dark muscle revealed that the major cause of lipid deterioration is hydrolysis. Hydrolysis resulted in an increase in free fatty acids by between 1 and 10%, particularly in the nutritionally important polyunsaturated n-3 fatty acids, 20:5 and 22:6. The phosphatidylcholine content of the muscle decreased by 25-50% during frozen storage. Phosphatidylethanolamine was stable in dark muscle but decreased in light muscle. By multivariate statistical evaluation it was possible to group the samples according to storage time or acclimatization temperature. A lower water temperature (5°C) resulted in reduced lipid stability during frozen storage. © 1995 American Chemical Society.