Toward sustainable material usage: evaluating the importance of market motivated agency in modeling material flows

Increasing recycling will be a key strategy for moving toward sustainable materials usage. There are many barriers to increasing recycling, including quality issues in the scrap stream. Repeated recycling can compound this problem through the accumulation of tramp elements over time. This paper explores the importance of capturing recycler decision-making in accurately modeling accumulation and the value of technologies intended to mitigate it. A method was developed combining dynamic material flow analysis with allocation of those materials into production portfolios using blending models. Using this methodology, three scrap allocation methods were explored in the context of a case study of aluminum use: scrap pooling, pseudoclosed loop, and market-based. Results from this case analysis suggest that market-driven decisions and upgrading technologies can partially mitigate the negative impact of accumulation on scrap utilization, thereby increasing scrap use and reducing greenhouse gas emissions. A market-based allocation method for modeling material flows suggests a higher value for upgrading strategies compared to a pseudoclosed loop or pooling allocation method for the scenarios explored.     

Optimisation of rancidity stability in long‐chain PUFA concentrates obtained from a rainbow trout (Oncorhynchus mykiss) by‐product

This research was focused on the production of polyunsaturated fatty acid concentrates from a farmed rainbow trout (Oncorhynchus mykiss) by‐product (i.e. belly muscle). The effect of different process variables (urea/fatty acids (FA) contents ratio, crystallisation time and temperature and stirring speed of the urea/FA mixture) on the lipid oxidation development during the urea complexation process was investigated. For this purpose, an experimental design (26 runs) following the response‐surface methodology was developed. As a result, peroxide value and TOTOX index showed to be dependent on the crystallisation time and temperature and the urea/FA ratio, while no influence of the crystallisation stirring speed was detected on both indices; additionally, polyene index was affected by the urea/FA ratio and its interaction with the crystallisation time. An optimised desirability score near 1.0 was attained provided values of 2.8 °C, 3.05 h and 3.57 were applied for crystallisation temperature, crystallisation time and urea/FA ratio, respectively.     

Cactus stem (Opuntia ficus‐indica Mill): anatomy,physiology and chemical composition with emphasis on its biofunctional properties

Cactus stem (Opuntia ficus‐indica Mill) is native to Mesoamerica and marketed in different forms such as fresh, frozen or pre‐cooked. Worldwide, this vegetable is recognized for its pharmaceutical actions, including its antioxidant, diuretic, anticarcinogenic, anti‐inflammatory, anti‐diabetic, and anti‐hypercholesterolemic properties, as well as their antiviral and antispermatogenic effects. However, not all of these properties have been associated with its chemical composition; therefore, this review aims to present and integrate information available on the physiology and anatomy of cactus stem and its chemical composition, focusing on some of the many factors that determine its biofunctionality. © 2017 Society of Chemical Industry     

Seed oils of ten traditional Portuguese grape varieties with interesting chemical and antioxidant properties

To increase the potential and better exploring of grape seeds that are an important wine-industrial waste, oils of ten traditional Portuguese grape varieties were evaluated in relation to their vitamin E content (tocopherols and tocotrienols), fatty acid profile, as well as, antioxidant properties. Our results showed that the grape-seed oils were a good source of γ-tocotrienol (499–1575 mg/kg), α-tocopherol (85.5–244 mg/kg) and α-tocotrienol (69–319 mg/kg). Concerning fatty acid profile, linoleic (C18:2cc), oleic (C18:1), palmitic (C16:0) and stearic (C18:0) acids were the predominant. Grape-seed oils demonstrated to be a good source of polyunsaturated fatty acids (PUFAs) (63.64–73.53%), whereas monounsaturated fatty acid (MUFA) and saturated fatty acid (SFA) ranged between 14.19–21.29% and 11.64–14.94%, respectively. Interesting values of DPPH and ABTS radical scavenging activities were also obtained. This study demonstrated that these seeds may be reused and their oils incorporated in other food products, taking into account the compounds with positive effects on human health that are present in their composition.     

Brominated flame retardants in archived serum samples from Norway: a study on temporal trends and the role of age

The temporal trends and influence of age and gender on levels of selected brominated flame retardants (BFRs) in human serum have been assessed by analyzing archived samples from Norway. Serum from 40 to 50 year old men collected at six time periods during 1977 to 1999 and from eight groups of differing age and gender sampled in 1998 were pooled into six and eight samples, respectively. The BFRs were isolated using solid-phase extraction (SPE) and the serum lipids decomposed bytreatmentwith concentrated sulfuric acid directly on the polystyrene-divinylbenzene SPE column, prior to elution of the BFRs. Following diazomethane derivatization, the samples were analyzed by gas chromatography-electron capture mass spectrometry. Eight BFRs were quantified in the serum samples: 2,4,4'-tribromodiphenyl ether (BDE-28), 2,2',4,4'-tetrabromodiphenyl ether (BDE-47), 2,2',4,4',5-pentabromodiphenyl ether (BDE-99), 2,2',4,4',6-pentabromodiphenyl ether (BDE-100), 2,2',4,4',5,5'-hexabromodiphenyl ether (BDE-153), 2,2',4,4',5,6'-hexabromodiphenyl ether (BDE-154), 2,4,6-tribromophenol (TriBP), and tetrabromobisphenol A (TBBP-A). The serum concentrations of all the BFRs, increased during the entire period with the exception of TriBP, and the sum of the six polybrominated diphenyl ethers increased from 0.44 ng/g lipids in 1977 to 3.3 ng/g lipids in 1999. The BFR concentrations in the serum from the different age groups were relatively similar, except for the age group 0-4 years, which had 1.6-3.5 times higher serum concentrations. Women older than 25 years had lower serum concentrations of BFRs compared to the corresponding group of men. No trend related to age or gender, nor time during the period 1977 to 1999 was observed for TriBP. The present study indicates an ongoing increase in human exposure to BFRs, and the current body burden appears to be independent of age, except for infants (0-4 years old), who seem to experience elevated exposure.