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Summary: Origin of coffee, precursors concentration, post‐harvesting processes and commercial roasting degrees were evaluated for their impact on acrylamide content in roasted coffee. Forty Seven Specialty Arabica and 7 high‐quality Robusta green coffee samples were analysed to determine sugars, asparagine and Aw. Acrylamide was quantified on light, medium and dark roasted samples. In green coffee, glucose and fructose content resulted lower after wet and honey processes, no remarkable differences were found for sucrose and asparagine. In all samples, the content of asparagine was generally lower than what provided in previous works. Acrylamide concentration never exceeded the limit of 400 μg kg−1 in Arabica samples and it does once in Robusta, it peaked between light and medium roasting, and it was higher in Robusta. Moreover, it was lower in honey coffee than in others. Acrylamide correlated with asparagine in Robusta, while with monosaccharides and Aw in dry and honey Arabica. Coffee Origin impacted on precursors and acrylamide. [ABSTRACT FROM AUTHOR]

Summary: Specialty coffee (SC) has been showing an increasing interest from the consumers which appreciate its traceability and the peculiar flavours from each single origin. Additionally, the processes to which coffee fruits underwent to get green coffee characterise the beans in terms of macromolecules acting as substrates during the roasting. This work evaluates via sensory analysed eight SC, roasted at light, medium, and dark level, submitted to Italian espresso extraction, to assess how different roasting levels exalt the expected cup profile obtained by the suppliers via cupping in origin countries. Finally, roasted beans were characterised for physico‐chemical features (pH, titratable acidity, caffeine, melanoidins, polyphenols and acrylamide). Sensory analysis demonstrated that the intermediate roasting level and espresso extraction match better attributes from in‐origin cupping. Melanoidins (mmol g−1 coffee d.b.) was able to discriminate among roasting levels (light 0.12 ± 0.01; medium 0.13 ± 0.003; dark 0.14 ± 0.01; α = 0.05). Acrylamide analyses ensured compliance with the food safety standards (light 301.9 ± 37.2 ppb; medium 126.1±19ppb; dark 107.9 ± 22.5ppb). Physico‐chemical features were able to cluster samples from different origins within the same roasting level (α = 0.05). Results showed correlations (α = 0.01) between sensory analysis and physico‐chemical values: direct for caffeine and astringency, reverse for perceived acidity in relation to astringency, roasted, dried fruits and nutty notes. [ABSTRACT FROM AUTHOR]

BACKGROUND A survey on 68 dairy farms was carried out to evaluate the ensiling procedures adopted to store corn silage. Samples from core, lateral and apical zones of the feed-out face of silos were analysed. A principal factor analysis ( PFA) was carried out on the entire database (196 silage samples and 36 variables) and 11 principal factor components ( PCs) were retained and interpreted. RESULTS Ensiling procedures influenced the area exposed to risk of air penetration. Cores had higher dry matter, starch and lactic acid content or lower pH, fibre, propionate and butyrate concentrations than peripheral samples ( P < 0.05). The highest ( P < 0.05) mycophenolic acid and roquefortina C concentrations were detected in lateral samples. Chemical and digestibility variables loaded on two PCs; four PCs were characterized by end-products associated with clostridia, heterolactic, homolactic and aerobic fermentations; two PCs were associated with mycotoxins, whereas three PCs explained ensiling procedures. CONCLUSION The main quality traits of corn silages differed throughout the entire silo face. Minimization of the area exposed to risk of air penetration represents the best strategy to preserve the nutritional value and safety of corn silages. PFA allowed a clusterization of original variables into 11 PCs, appearing able to discriminate well and poorly preserved corn silages. © 2015 Society of Chemical Industry [ABSTRACT FROM AUTHOR]