Improvement of Paper Resistance against Moisture and Oil by Coatings with Poly(-3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) and Polycaprolactone (PCL)

Surface hydrophobicity and grease resistance of paper may be achieved by the application of coatings usually derived from fossil-oil resources. However, poor recyclability and environmental concerns on generated waste has increased interest in the study of alternative paper coatings. This work focuses on the study of the performances offered by two different biopolymers, poly(3hydroxybutyrate-co-3hydroxyvalerate) (PHBV) and polycaprolactone (PCL), also assessing the effect of a plasticizer (PEG) when used as paper coatings. The coated samples were characterized for the structural (by scanning electron microscopy, SEM), diffusive (water vapor and grease barrier properties), and surface properties (affinity for water and oil, by contact angle measurements). Samples of polyethylene-coated and fluorinated paper were used as commercial reference. WVTR of coated samples generally decreased and PHBV and PCL coatings with PEG at 20% showed interesting low wettability, as inferred from the water contact angles. Samples coated with PCL also showed increased grease resistance in comparison with plain paper. This work, within the limits of its lab-scale, offers interesting insights for future research lines toward the development of cellulose-based food contact materials that are fully recyclable and compostable

Mitigation of Acrylamide Content in Biscuits through Combined Physical and Chemical Strategies

Acrylamide in biscuits represents a major concern. This research work was aimed at modifying the current formulation of biscuits to reduce the acrylamide content while maintaining the chemical, physical, and sensory characteristics of the original product. A strategy based on the FoodDrinkEurope Acrylamide Toolbox was adopted. The content of the leavening agent ammonium bicarbonate, the baking temperature program, and the time duration of steam released during the baking process were the three factors evaluated through a factorial design of experiment. The partial replacement of ammonium bicarbonate (from 9.0 g to 1.5 g per 500 g of flour) with sodium bicarbonate (from 4.5 g to 12.48 g), lowering of the temperature in the central phase of the baking process (from 170 degrees C to 150 degrees C), and the release of steam for 3 min resulted in an 87.2% reduction in acrylamide concentration compared to biscuits of reference. CIELab color indices and a(w) were the parameters that showed the most significant correlation with acrylamide concentration in biscuits and could, therefore, become markers to predict the acrylamide content along production lines for an instant evaluation

Polycaprolactone/Starch/Agar Coatings for Food-Packaging Paper: Statistical Correlation of the Formulations’ Effect on Diffusion, Grease Resistance, and Mechanical Properties

Paper is one of the most promising materials for food packaging and wrapping due to its low environmental impact, but surface treatments are often needed to improve its performance, e.g., the resistance to fats and oils. In this context, this research is focused on the formulation of a new paper bio-coating. Paper was coated with liquids containing poly(hexano-6-lactone) (PCL), glycerol and variable percentages of starch (5–10% w/w PCL dry weight), agar-agar (0–1.5% w/w PCL dry weight), and polyethylene glycol (PEG) (5% or 15% w/w PCL dry weight) to improve coating uniformity and diffusion. A design of experiments approach was implemented to find statistically reliable results in terms of the best coating formulation. Coated paper was characterized through mechanical and physical properties. Results showed that agar content (1.5% w/w PCL dry weight) has a beneficial effect on increasing the resistance to oil. Furthermore, the best coating composition has been calculated, and it is 10% w/w PCL dry weight of starch, 1.5% w/w PCL dry weight of agar, and 15% w/w PCL dry weight of PEG

Strategies for acrylamide mitigation in biscuits

Food safety deals with handling, preparation (processing), and storage of food to prevent food-borne illness. During all these phases, food might be subject to microbial, physical, and chemical contamination. Acrylamide is a process contaminant that is formed during heat treatment of food rich in proteins and sugars, while it is absent in raw foodstuffs. Most acrylamide is formed primarily through the Maillard reaction, which specifically involves the amino group of asparagine, the carbonyl group of reducing sugars, and intermediate molecules of the Maillard reaction. Acrylamide in biscuits represents a major concern. To date, there are no technological strategies to completely prevent acrylamide formation, although there are some ways to mitigate its concentration in food. This research work was aimed at modifying the current formulation of biscuits to reduce the acrylamide content while maintaining the chemical, physical, and sensory characteristics of the original product. A strategy based on the FoodDrinkEurope Acrylamide Toolbox was adopted. The content of the leavening agent ammonium bicarbonate, the baking temperature program, and the time duration of steam released during the baking process were the three factors evaluated through a factorial design of experiment. The partial replacement of ammonium bicarbonate (from 9.0 g to 1.5 g per 500 g of flour) with sodium bicarbonate (from 4.5 g to 12.48 g), lowering of the temperature in the central phase of the baking process (from 170 °C to 150 °C), and the release of steam for 3 min resulted in an 87.2% reduction in acrylamide concentration compared with control biscuits. Different analyses were performed on the sample set, CIELab color indices and aw were the parameters that showed the most significant correlation with acrylamide concentration in biscuits and could, therefore, become markers to predict the acrylamide content along production lines for an instant evaluation

ToF-SIMS and XPS charcterisation of urban aerosols for pollution studies

Huge amount of particulate matter are endlessly released in the atmosphere by anthropogenic, industrial and natural sources. Since aerosols play a fundamental role in the physical and chemical processes governing the global climate and strongly affects human health as well, their characterisation focus a steadily growing interest. In the present work, the usefulness of ToF-SIMS and XPS for aerosol characterisation is evaluated. In particular, urban aerosols are considered for introductory assessment of techniques helpfulness for pollution-related studies

ToF-SIMS study of adhesive residuals on device contact pads after wafer taping and backgrinding

Wafer thinning prior to bonding and packaging of integrated circuits (IC) is accomplished by back-surface grinding using abrasive tools. At this stage of device fabrication, most of the IC surface but the contact pads is covered by the passivation layer. Being unprotected, the pads could thus be easily contaminated by particles and chemicals. An adhesive tape is commonly used to shield the IC front surface. However, adhesive residuals that can detrimentally affect the pad/wire bonding and seriously alter the sticking of the package plastic with the device surface can be likely present as a consequence. TOF-SIMS was used to investigate the adhesive residuals on the contact pads after using different tapes, allowing to recognise the compounds transferred from time to time on the IC surface. Semi-quantitative evaluations of the adhesive residual amount after exploiting several cleaning recipes were also obtained, allowing the tailoring of the cleaning process parameters after contamination identificatio

Conservation-Compatible Retrofit Solutions in Historic Buildings: An Integrated Approach

Historic, listed, or unlisted, buildings account for 30% of the European building stock. Since they are complex systems of cultural, architectural, and identity value, they need particular attention to ensure that they are preserved, used, and managed over time in a sustainable way. This implies a demand for retrofit solutions able to improve indoor thermal conditions while reducing the use of energy sources and preserving the heritage significance. Often, however, the choice and implementation of retrofit solutions in historic buildings is limited by socio-technical barriers (regulations, lack of knowledge on the hygrothermal behaviour of built heritage, economic viability, etc.). This paper presents the approach devised in the IEA-SHC Task 59 project (Renovating Historic Buildings Towards Zero Energy) to support decision makers in selecting retrofit solutions, in accordance with the provision of the EN 16883:2017 standard. In particular, the method followed by the project partners to gather and assess compatible solutions for historic buildings retrofitting is presented. It focuses on best practices for walls, windows, HVAC systems, and solar technologies. This work demonstrates that well-balanced retrofit solutions can exist and can be evaluated case-by-case through detailed assessment criteria. As a main result, the paper encourages decision makers to opt for tailored energy retrofit to solve the conflict between conservation and energy performance requirements