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The objective of this study was to evaluate the relative impact of 12 odour-active compounds on the odours of three different non-processed semi-hard kinds of cheese using a combination of different odour stimulation tools. Based on a previous study, eight odorants were identified as contributors to the basic odour of the cheeses, and four additional odorants were identified as contributors to the specificity of each cheese. The eight basic odorants were dispatched into four vessels of an olfactometer, which delivered mixtures following a Box-Behnken design. Each odour mixture was compared with each real cheese odour based on a direct similarity rating. An optimal basic composition of the four olfactometer vessels for each of the three cheeses was obtained. One vessel that contained a mixture of four odorants significantly impacted the odour similarity scores; thus, the four odorants (3-methyl butane-1-ol, butanoic acid, 3-methylbutanoic acid and dimethyl trisulphide) were individually tested along with four additional odorants (2,3-dimethyl pyrazine, benzaldehyde, methyl 2-methyl-3-furyl disulphide and gamma heptalactone) in a second experiment using the olfactoscan technique. A paired comparison between real cheese odours and the odour mixtures delivered by the olfactometer combined with odorants eluted from a gas-chromatograph indicated that dimethyl trisulphide primarily contributed to one of the cheese odours and butanoic acid contributed to another cheese odour. Gamma heptalactone had a positive impact, whereas benzaldehyde and 1-octen-3-one had a negative impact, on the similarity between the recombined odour and the odour of the third cheese. This original approach is a promising tool for the reformulation of food aromas.

The purpose of this study was to investigate semi-hard cheese aroma by explaining sensory characteristics of cheese by gas chromatography–olfactometry (GC–O) data obtained via intensity ratings. Sensory (13 odour attributes) and GC–O profiles obtained by trained panels were carried out on seven non-processed semi-hard cheeses. Intensity scores for significant sensory attributes and significant odour-active compounds were analysed by partial least squares to determine correlations between these datasets. A total of nine sensory attributes and 15 odour-active molecules significantly discriminated between the cheeses. There were strong correlations (89% of the sensory data was explained by 68% of the GC–O data) between sensory attributes and odour-active compounds. We observed expected correlations between the sensory sweaty-attribute and carboxylic acids, but also observed less trivial correlations suggesting that perceptual interactions could take place within the complex cheese aroma. Correlations between sensory attributes and odour-active compounds with very low-perception thresholds were also observed.

As a response to the economic crisis and sustainability challenges the world is facing, the discussion related to green growth and green economy was launched by the Organisation for Economic Co-operation (OECD) and United Nations Environment Programme. Green growth and green economy have been seen as opportunities to foster economic growth and development, while ensuring that natural assets continue to provide the resources and ecosystem services on which our well-being relies. The central message is that greening the economies can help to generate new jobs and skills, promote clean technologies, and reduce environmental risks and poverty. This report summarises the key results of a PEER project analysing the green economy. The project explored green economy concepts and 10 practical cases from Finland, France, Germany, the Netherlands and Denmark. The work is based on three article manuscripts and thus divided into three parts: 1) a conceptual and methodological framework for the implementation and the monitoring of the different dimensions of a green economy (Loiseau et al., 2015), 2) critical factors for achieving a green economy in practice (Pitkänen et al., 2015), and 3) governance factors with respect to institutional frameworks that may facilitate a transition to a green economy (Droste et al., 2015). The concept of a green economy can encompass several meanings and be related to different economic theories, concepts and practical approaches aiming to achieve environmental, economic and social benefits. In order to measure the effects of these solutions, different assessment tools can be used. The concepts and practical approaches related to the green economy are varyingly implemented in the cases of enhancing green economy in practice. For instance, principles of industrial ecology lie behind several of our case study approaches. Similarly, circular economy and waste hierarchy concepts were present in several of the studied cases, combined for instance with energy or material efficiency approaches. The results emphasise that transitioning to green economies is never purely based on win-win solutions, but requires taking into account potential trade-offs among multiple goals, across sectors and international leakage. The case studies indicate the need for far-sighted and multiple-source planning of funding of green economy initiatives. The results emphasise a better and more holistic integration of research in green economy initiatives and projects from the beginning. As illustrated by our study, the complexity and multi-sectoral nature of the green economy calls for a broad co-integration of policies bridging the environment, innovation, transport, housing, energy, agriculture and spatial planning. Our case studies also illustrate the need for comprehensive analysis of the effects of regulation and legislation. Many of our cases also illustrate the importance of stakeholder commitment, good leadership and coordination. Transforming the economy requires innovation in terms of available technology, organisational support, market and broader societal conditions, and an overarching governance framework, but most of all, political will. The practical implementation of the green economy is related to a multiplicity of factors and causalities depending on the context. Some solutions are more compliant with the mainstream economy and require few changes (e.g. cleaner production), whereas other solutions are more system-oriented and based on profound transformations in the patterns of production and consumption (e.g. industrial ecology).

A new and original statistical approach was used to compare the effectiveness of 4 different methods to analyse aroma compounds of seven different commercial semi-hard cheeses with regard to their orthonasal sensory perception. Four extraction methods were evaluated: Purge and Trap, Artificial Mouth, Solid-Phase Microextraction (SPME) and Solvent-Assisted Flavour Evaporation (SAFE). Among the headspace methods, Artificial Mouth gave the closest representation of the studied product space to the sensory perception one. The SAFE method was complementary to the dynamic headspace methods, as it was very efficient in extracting the heavy molecules but less efficient for extracting the most volatile compounds. SPME and Purge and Trap gave intermediate representations. At the product level, results indicate that carboxylic acids are present in similar amounts in the different commercial marks of semi-hard cheeses, that esters and aldehydes vary in small proportions and that the proportions of sulphur compounds, alcohols and ketones mainly explain the sensory differences between the commercial marks.