Efficient and accurate simulation of the packaging forming process

To allow for large‐scale forming applications, such as converting paperboard into package containers, efficient and reliable numerical tools are needed. In finite element simulations of thin structures, elements including structural features are required to reduce the computational cost. Solid‐shell elements based on reduced integration with hourglass stabilization is an attractive choice. One advantage of this choice is the natural inclusion of the thickness, not present in standard degenerated shells, which is especially important for many problems involving contact. Furthermore, no restrictions are imposed on the constitutive models since the solid‐shell element does not require the plane stress condition to be enforced. In this work, a recently proposed efficient solid‐shell element is implemented together with a state‐of‐the‐art continuum model for paperboard. This approach is validated by comparing the obtained numerical results with experimental results for paperboard as well as with those found by using 3D continuum elements. To show the potential of this approach, a large‐scale forming simulation of paperboard is used as a proof of concept.     

在减少碳足迹的道路上——Stora Enso集团减少碳足迹实例

近年来,为了人类的可持续发展和应对全球气候变暖,减少碳排放及发展低碳经济已成为全球共识。林纸产品行业在遏制气候变化方面握有先机,可持续森林和人工林管理在减缓气候变化方面发挥着重要作用。     

Computer aided boar semen motility analysis for cereulide detection in different food matrices

Computer Aided Semen Analysis (CASA) study of the boar semen motility has been demonstrated to be an appropriate assay for detection of cereulide (Bacillus cereus emetic toxin). Application of the boar semen bio-assay to detect cereulide directly in foods requires investigation of potential interference of food components, preservatives and other microbial and chemical food contaminants with the bio-assay. Current study provides evidence that none of included Staphylococcus aureus enterotoxins A, B, C and D nor B. cereus Hemolysin BL (HBL) and non-hemolytic enterotoxin (NHE) and three mycotoxins (Sterigmatocystin, Fumonisin B1 and Patulin) exhibited a toxic impact on semen progressive motility. Aflatoxin M1, M3 and zearalenone impaired semen motility only at concentrations (0.004 mg ml(-1), 0.1 mg ml(-1) and 10 mg ml(-1), respectively) much higher than those found in foods and those permitted by legislation, in comparison to cereulide which induces motility cease at concentrations lower than 20 ng ml(-1). Ten commonly used preservatives, namely potassium sorbate, sodium benzoate, (DL) malic acid, citric acid, (L+) tartaric acid, acetic acid, (DL) lactic acid, (L+) ascorbic acid, sodium chloride and sucrose induced no cease in spermatozoa motility even at preservative concentrations higher than permitted by legislation. Dioxins, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD), and acrylamide had no acute effect on spermatozoa motility at concentrations of 500 and 10,000 mg ml(-1), respectively. Robustness of computer aided boar semen motility analysis, tested with 14 different foods inoculated with cereulide producing B. cereus, showed distinct cereulide production in seven samples (although B. cereus growth to counts higher than 8 log CFU g(-1) was noted in 11 samples), in amounts close to those reported in foodborne outbreaks. Test evaluation in 33 samples suspected to hold cereulide showed actual cereulide presence in ten samples and no interference of food matrix with the assay.     

Pasting,thermal, gel texture,resistant starch and colour properties of unripe banana flour from 10 desert banana varieties cultivated in South Africa

Unripe banana flour is a potential commercial ingredient in various food products for increased resistant starch and reduced gluten contents. In the present study, the pasting (rapid visco-analysis), gel texture (penetration test), thermal (differential scanning calorimetry), colour (tri-stimulus colour indices) and the resistant starch properties of unripe banana flour produced from different dessert banana varieties (n?=?10) cultivated in South Africa, were analysed and juxtaposed to wheat and maize flour. The functional properties varied significantly (p?≤?0.05) between banana varieties, and from wheat and maize flours, to various extents. Selected functional property ranges of unripe banana, wheat and maize flours, respectively included; flour colour index (63.16–76.42, 77.34 and 80.96), paste viscosity (405.5–556.6, 124.7 and 115.6 RVU), gelatinization temperature (64.67–71.21, 71.11 and 69.95?°C), gel firmness (7.24–11.44?×?10^??2 N, 3.49?×?10^??2 N and 6.56?×?10^??2 N) and resistant starch content (19.9–47.4, 2.8 and 2.2% w/w). Multivariate analysis (principle component analysis) showed that the unripe banana flours from different varieties were distinguished from each other based on the pasting temperature. The unripe banana flours were distinguished from both wheat and maize flour based on breakdown and peak paste viscosities. The breakdown viscosity was the most positively related measure to the resistant starch content with a linear regression R-squared value of 0.898, indicating a significant role played by granule structure in resistance to enzymatic hydrolysis. The present research demonstrates that selection of appropriate dessert banana variety is important when replacing staple flours (wheat and maize) with unripe dessert banana flour as a functional ingredient.     

The Saccharomyces cerevisiae alcohol acetyl transferase Atf1p is localized in lipid particles

The yeast alcohol acetyl transferase I, Atf1p, is responsible for the major part of volatile acetate ester production in fermenting Saccharomyces cerevisiae cells. Some of these esters, such as ethyl acetate and isoamyl acetate, are important for the fruity flavours of wine, beer and other fermented beverages. In order to reveal the subcellular localization of Atf1p and further unravel the possible physiological role of this protein, ATF1::GFP fusion constructs were overexpressed in brewer's yeast. The transformant strain showed a significant increase in acetate ester formation, similar to that of an ATF1 overexpression strain, indicating that the Atf1p-GFP fusion protein was active. UV fluorescence microscopy revealed that the fusion protein was localized in small, sphere-like organelles. These organelles could be selectively stained by the fluorescent dye Nile red, indicating that they contained high amounts of neutral lipids and/or sterols, a specific characteristic of yeast lipid particles. Purification of lipid particles from wild type and ATF1 deletion cells confirmed that the Atf1p-GFP fusion protein was located in these organelles. Furthermore, a clear alcohol acetyl transferase activity could be measured in the purified lipid particles of both wild type and transformed cells. The localization of Atf1p in lipid particles may indicate that Atf1p has a specific role in the lipid and/or sterol metabolism that takes place in these particles.     

Synergy between bio‐based industry and the feed industry through biorefinery

Processing biomass into multi‐functional components can contribute to the increasing demand for raw materials for feed and bio‐based non‐food products. This contribution aims to demonstrate synergy between the bio‐based industry and the feed industry through biorefinery of currently used feed ingredients. Illustrating the biorefinery concept, rapeseed was selected as a low priced feed ingredient based on market prices versus crude protein, crude fat and apparent ileal digestible lysine content. In addition it is already used as an alternative protein source in diets and can be cultivated in European climate zones. Furthermore, inclusion level of rapeseed meal in pig diet is limited because of its nutritionally active factors. A conceptual process was developed to improve rapeseeds nutritional value and producing other bio‐based building blocks simultaneously. Based on the correlation between market prices of feed ingredients and its protein and fat content, the value of refined products was estimated. Finally, a sensitivity analysis, under two profit scenario, shows that the process is economically feasible. This study demonstrates that using biorefinery processes on feed ingredients can improve feed quality. In conjunction, it produces building blocks for a bio‐based industry and creates synergy between bio‐based and feed industry for more efficient use of biomass. © 2015 Society of Chemical Industry     

The effect of inoculum size on the growth of Penicillium expansum in apples

Penicillium expansum is the most important cause of blue mould rot, a major post-harvest disease of apples worldwide. The objective of this study was to evaluate the effect of the inoculum size on the germination and growth parameters of P. expansum under different storage conditions in apples. Growth of P. expansum was observed in more than 90% of the inoculations, when the inoculum was equal or higher than 2x10(4) spores. The use of a low inoculum level resulted in longer lag phases and a larger variability of the estimated lag phase. This indicates that more replications are necessary to estimate the lag phase of the mould in the specified circumstances. At lower temperature, more inoculum was necessary to reduce the variability of the estimated lag phase, showing that this effect is temperature dependent. Moreover, the effect of the inoculum level on the lag phase is even more pronounced for a slower growing strain. These results imply that the inoculum size influences the estimated growth parameters and should be considered in quantitative risk assessments and for the design of challenge tests and experiments to gather data for predictive growth models.