Assessment of technical and environmental performances of wheat‐based foams in thermal packaging applications

This paper presents an assessment of the technical and environmental performance of a wheat‐based foam (WBF) and bio‐composite for shipping chilled products. The thermal conductivity of the WBF was found to be higher than that of polyurethane foams commonly used in high‐value insulation packaging, but close to that of low‐density (expanded polystyrene) EPS foams and significantly lower than that of polyethylene (PE) foams, which are typically used in thermal packaging of foods. The insulation performance of a simple cool box constructed from both the WBF and EPS sandwich panels without the use of any refrigerant was studied experimentally. The comparison demonstrated that the performance of the WBF cool box was comparable to that of the EPS counterpart. Two industrial case studies were conducted on WBF cool boxes with refrigerants in comparison with PE or EPS counterparts. The WBF cool boxes had comparable thermal performance to the EPS and PE counterparts on the basis of identical foam thickness. The performance of the WBF cool boxes was also simulated with finite element (FE) modelling. Good agreement was achieved between experimental data and the FE prediction. The model was then used to assist cool box design. WBF cool boxes made from renewable raw materials are inherently biodegradable and may be used as an alternative to those based on polymer foams in thermal packaging applications. Life‐cycle assessment (LCA) was used to investigate environmental profiles of cool boxes made with WBF, EPS and PE foams. The WBF cool boxes offer substantially lower global warming and abiotic depletion potentials than equivalent cool boxes made from petrochemical foams. Copyright © 2010 John Wiley & Sons, Ltd.     

Potential of migration of active compounds from protein‐based films with essential oils to a food and a food simulant

Migration tests at different temperatures and storage periods were performed to evaluate the release of active compounds from active whey protein films (WPFs) to a food and food simulants. Whey protein film incorporated with different levels of an optimized essential oils (EOs) blend (1%, 2%, 2.7%, and 5%, w/w) were prepared by casting. This blend contained EOs from rosemary and 2 species of cinnamon. Salami was packaged with WPF and stored during 180 days at 5°C. Temperature influenced significantly the migration of compounds (P<.1). It was observed that eucalyptol was the compound that presented the highest potential of migration into 95% ethanol (v/v). After contact of film with salami, it was observed that, in general, more than 50% of active compounds released from WPF to salami. It was observed that higher amounts of active compounds were released to salami than to fatty food simulant. Results suggested that the release of compounds depends on their affinity with the food/food simulant, temperature, their concentration in packaging, and composition of food. Active packaging may ensure the quality of food due the migration of compounds from EO with antimicrobial and antioxidant activity incorporated in the film to the foodstuff.     

Migrants from food cans revisited – application of a stochastic model for a more realistic assessment of exposure to bisphenol A diglycidyl ether (BADGE)

We have used a two‐dimensional probabilistic model to estimate the short‐term dietary exposure of UK consumers to bisphenol A diglycidyl ether (BADGE) migrating from light metal food packaging. Using three UK National Dietary and Nutrition Surveys comprising 4–7‐day dietary surveys for different ages and genders, actual body weights and survey years, a sample representative of the UK population was obtained, comprising around 4200 food items. The packaging type of each food item was assigned by utilizing known packaging type from the database or by sampling from a distribution based upon market share information or expert judgement. For concentration data, we have used published data for foods or food simulants or a combination of both. The probabilistic approach allowed sensitivity analysis to evaluate the relative importance of the input parameters and placed confidence bounds on the outputs to show the effect of the uncertainties. The refined estimates gave an exposure for UK consumers, at the 97.5th percentile level, of 0.41–0.83 μ/kg body weight (bw)/day for the different age ranges and scenarios run. All estimates are well below the new tolerable daily intake value of 150 μ/kg bw/day for BADGE and its two hydrolysed forms, and are also well below the restriction value of 17 μ/kg bw/day for the other regulated BADGE derivatives. The main contributors to exposure are beverages, along with aqueous and acidic foods. This is because of the high consumption of these classes of foodstuffs, even though levels of migration into these foodstuffs and into their appropriate simulants is normally non‐detectable. Reducing the non‐detectable level six‐fold reduced the estimate of exposure by 40–60%. Copyright © 2006 John Wiley & Sons, Ltd.     

Determination of ϵ‐caprolactam migration from polyamide plastics: a new approach

A new gas chromatography method for determination of ?‐caprolactam (CPR) migration from packaging materials such as: polyamide (PA) films, PA granulates, PA/PE (polyethylene) laminates, PA casings, etc., to food simulants has been developed. Water, 3% w/v acetic acid, 15% and 95% v/v ethanol and olive oil have been used as a food simulants. Using the 1,4‐butanediol (BUG) as an internal standard (instead of aza‐2‐cyclononanone), calibration curves were constructed. Very good separation of CPR from BUG was achieved by using a Nukol fused silica capillary column (Supelco), 25 m × 0.32 mm. The time of analysis is shorter than 12 min: 7.69 min for BUG and 11.60 min for CPR. The regression line equation for CPR migration to water is: y = 0.080x + 0.14; to olive oil: y = 0.010x. The sensitivity of the developed method is appropriate for the quantitative determination of CPR in an analyte concentration of approximately 0.2 mg/kg, when the specific migration limit (SML) for this compound, according to Directive 90/128/EEC, is 15 mg/kg food simulant. Copyright © 2001 John Wiley & Sons, Ltd.