Developing high-quality gluten-free bakery products

Author institution (Vodovotz): Department of Food Science and Technology, The Ohio State Universit

The sustainable materials roadmap

Over the past 150 years, our ability to produce and transform engineered materials has been responsible for our current high standards of living, especially in developed economies. However, we must carefully think of the effects our addiction to creating and using materials at this fast rate will have on the future generations. The way we currently make and use materials detrimentally affects the planet Earth, creating many severe environmental problems. It affects the next generations by putting in danger the future of the economy, energy, and climate. We are at the point where something must drastically change, and it must change now. We must create more sustainable materials alternatives using natural raw materials and inspiration from nature while making sure not to deplete important resources, i.e. in competition with the food chain supply. We must use less materials, eliminate the use of toxic materials and create a circular materials economy where reuse and recycle are priorities. We must develop sustainable methods for materials recycling and encourage design for disassembly. We must look across the whole materials life cycle from raw resources till end of life and apply thorough life cycle assessments (LCAs) based on reliable and relevant data to quantify sustainability. We need to seriously start thinking of where our future materials will come from and how could we track them, given that we are confronted with resource scarcity and geographical constrains. This is particularly important for the development of new and sustainable energy technologies, key to our transition to net zero. Currently 'critical materials' are central components of sustainable energy systems because they are the best performing. A few examples include the permanent magnets based on rare earth metals (Dy, Nd, Pr) used in wind turbines, Li and Co in Li-ion batteries, Pt and Ir in fuel cells and electrolysers, Si in solar cells just to mention a few. These materials are classified as 'critical' by the European Union and Department of Energy. Except in sustainable energy, materials are also key components in packaging, construction, and textile industry along with many other industrial sectors. This roadmap authored by prominent researchers working across disciplines in the very important field of sustainable materials is intended to highlight the outstanding issues that must be addressed and provide an insight into the pathways towards solving them adopted by the sustainable materials community. In compiling this roadmap, we hope to aid the development of the wider sustainable materials research community, providing a guide for academia, industry, government, and funding agencies in this critically important and rapidly developing research space which is key to future sustainability.journal articl

Classification of the characteristics of two mango cultivars harvested at different stages of maturity using gas chromatography and sensory data

The classification of the characteristics of two Mexican mango varieties (Tommy Atkins and Haden) ripened under two conditions (in cold storage and on the tree) was attempted using several multivariate analysis techniques. The aroma of the different mango purees was analyzed using both capillary gas chromatography and sensory analysis. A new portable gas chromatograph (SRI model 8610, Torrance, CA) equipped with a purge and trap was used and the area count of relevant peaks calculated. These results and those obtained from a sensory panel comprised the classification factors. In addition, parameters such as the Magness Taylor pressure values, pH and acid/sugar ratio were determined. Two familiar classification techniques namely Principal Component Analysis (PCA) and Linear Discriminant Analysis (LDA) were used as well as a new program developed in our laboratory: PCA- Similarity (PCA-SIM). Results showed that differences exist between varieties as well as ripening conditions when analyzed both by GC and sensory techniques. Distinct groups were formed when the results of these techniques were independently subjected to LDA and PCA-SIM. PCA was more successful as a variable reduction technique than a classification method. Although both GC and sensory methods were successful in characterizing the differences between the groups, one could not replace the other since no correlation was found between the two methods. The other physico/chemical parameters were useful, but only to a limited extent, and none could account for both differences between varieties and ripening conditions.Land and Food Systems, Faculty ofGraduat

Aging of starch and bread as studied by DSC, DMA, NMR and confocal microscopy

Structural, thermo-mechanical and molecular changes in starch gels and bread were studied at variable moisture contents, storage times and temperature. Glassy-rubbery transition was characterized in systems with and without freezable water using thermal analysis and NMR (Nuclear Magnetic Resonance). Dynamic Mechanical Analysis (DMA) in conjunction with Differential Scanning Calorimetry (DSC) were used to describe structural relaxation (long range) while \sp1H cross-relaxation NMR and \sp{13}C CP-MAS (Cross-Polarization/Magic Angle Spinning) NMR were used to observe the starch molecular motions (short range). DMA results showed a transition region covering a large temperature range which was found to be moisture dependent. Overlapping tan $\delta$ (T) curves were deconvoluted into asymmetric double Sigmoidal curve (glassy-rubbery transition) and Gaussian curve (ice melting). The latter was found to highly correlate with the amount of freezable water (DSC data). The asymmetric curve was also confirmed as a glassy-rubbery transition on a molecular level using \sp1H cross-relaxation NMR and \sp{13}C CP-MAS NMR. Both NMR data showed a decrease in starch mobility with lowering temperature around the asymmetric (glassy-rubbery) transition observed by DMA. As the moisture content decreased so that the amount of freezable water was depleted, the transition temperature range increased, shifting to a higher temperature, typical of a glassy-rubbery transition. Firming of aging starch gels was related to amylopectin recrystallization (which followed amylose crystallization), glassy-rubbery transition or network formation (DMA), starch molecular mobility (NMR) and freezable water. A distribution of glassy-rubbery transition temperatures increased with storage time. The structural network was nonuniformly distributed leading to heterogeneous domains exhibiting different glassy-rubbery transition temperatures. However, only increased overall solid fractions (intensity) was observed by both \sp1H cross-relaxation and \sp{13}C CP-MAS NMR methods but no change in the molecular transition temperature range. This suggested that the network formation formed during the aging of starch did not occur on the molecular level but on a structural one

Synergistic Mechanisms Underlie the Peroxide and Coagent Improvement of Natural-Rubber-Toughened Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Mechanical Performance

Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a promising bio-based and biodegradable thermoplastic with restricted industrial applications due to its brittleness and poor processability. Natural rubber (NR) has been used as a toughening agent, but further physical improvements are desired. In this study, rubber toughening efficiency was significantly improved through the synergistic use of a trifunctional acrylic coagent and an organic peroxide during reactive extrusion of PHBV and NR. The rheological, crystallization, thermal, morphological, and mechanical properties of PHBV/NR blends with 15% rubber loading were characterized. The peroxide and coagent synergistically crosslinked the rubber phase and grafted PHBV onto rubber backbones, leading to enhanced rubber modulus and cohesive strength as well as improved PHBV–rubber compatibility and blend homogeneity. Simultaneously, the peroxide–coagent treatment decreased PHBV crystallinity and crystal size and depressed peroxy-radical-caused PHBV degradation. The new PHBV/NR blends had a broader processing window, 75% better toughness (based on the notched impact strength data), and 100% better ductility (based on the tensile elongation data) than pristine PHBV. This new rubber-toughened PHBV material has balanced mechanical performance comparable to that of conventional thermoplastics and is suitable for a wide range of plastic applications

Effect of chickpea protein concentrate on the loaf quality of composite soy-wheat bread

Soy bread has been successfully reformulated with chickpea protein concentrate to expand saponin profile of the product. The aim of the current study was to ascertain the quality of changes resulting from this reformulation. Chickpea protein concentrate deleteriously affected textural quality of the bread at 2/3 of soy substitution, resulting in higher hardness, chewiness and lower specific loaf volume, while a 1/3 of soy substitution was found to be a viable tool to deliver a diverse saponin profile, without negative effects on texture, other than a limited increase in hardness

Use of 1H cross-relaxation nuclear magnetic resonance spectroscopy to probe the changes in bread and its components during aging

1H nuclear magnetic cross-relaxation spectroscopy was used to probe the molecular mobility/rigidity in bread and its components during storage. The Z-spectra lineshapes, attributed to the solid-like polymer fractions of the samples, differed for the bread, gelatinized waxy starch (GX), gelatinized wheat starch (GW), heated flour (HF), and heated gluten (HG). Upon storage, no change was observed in the Z-spectrum of the bread sample, while the Z-spectra for GX, GW, and HG increased in the width at half height of the decomposed broad component (increased rigidity). These trends in the Z-spectra detected by NMR were contradictory to the DSC results that showed an increase in amylopectin retrogradation enthalpy for all samples containing starch, including bread. These trends in the Z-spectra detected by NMR were not reflected by the DSC results that showed an increase in amylopectin retrogradation enthalpy for all samples, including bread. The differences in molecular mobility could not be therefore, due to recrystallized amylopectin and may be attributed to the role of gluten and/or redistribution of water in the amorphous regions of the samples