Through an examination of transport planning in Australia, this book challenges conventional wisdom by showing, through original research, how 'car dependence' is as much an institutional as a ...technical phenomenon. The authors' case studies in three metropolitan cities show how transport policy has become institutionally fixated on a path dominated by private, road-based transport and how policy systems become encrusted around investment to accommodate private cars, erecting an impenetrable barrier against more sustainable mobility and accessibility solutions. The findings are applicable to most cities of the developed world, and to fields beyond transport planning.
The physicochemical and emulsifying properties of lentil protein isolates (LPI) were investigated as a function of their degree of hydrolysis (DH of 4, 9 and 20%) following exposure to trypsin/heat. ...Specifically, interfacial tension, surface characteristics (charge and hydrophobicity) and intrinsic fluorescence were determined. These parameters were then related to changes in the emulsification activity (EAI) and stability indices (ESI) of unhydrolyzed (u-LPI) and hydrolyzed LPI (h-LPI) in a flaxseed oil–water emulsion. Interfacial tension was found to decrease from ~6.5 to ~6.1mN m−1 for u-LPI and h-LPI (DH 4–20%), respectively. A similar trend was observed for surface hydrophobicity, which declined from ~30 to ~24 for the u-LPI and h-LPI (DH 4–20%), respectively. In contrast, surface charge values were similar for all materials (~−37mV). Intrinsic fluorescence as a function of emission wavelengths (300–400nm) indicated a slight change in the tertiary conformation of LPI upon hydrolysis, where the magnitude of fluorescence intensity declined relative to that of u-LPI. Changes in physicochemical properties upon hydrolysis had a detrimental effect on EAI and ESI values, which declined from ~51 to ~47m2g−1 and ~12 to ~11min for u-LPI and h-LPI (DH 4–20%), respectively.
► Limited hydrolysis of lentil proteins negatively impacted emulsifying properties. ► Limited hydrolysis of lentil proteins led to a decrease in surface hydrophobicity. ► Physiochemical and emulsifying properties were similar over the DH range of 4–20.
The emulsifying (emulsion capacity, EC; emulsion activity/stability indices, EAI–ESI and creaming stability, CS) and physicochemical properties (surface charge/hydrophobicity, protein solubility, ...interfacial tension, and droplet size) of chickpea (ChPI), faba bean (FbPI), lentil (LPI), and pea (PPI) protein isolates produced by isoelectric precipitation and salt extraction were investigated relative to each other and a soy protein isolate (SPI). Both the legume source and method of isolate production showed significant effects on the emulsifying and physicochemical properties of the proteins tested. All legume proteins carried a net negative charge at neutral pH, and had surface hydrophobicity values ranging between 53.0 and 84.8 (H
0-ANS), with PPI showing the highest value. Isoelectric precipitation resulted in isolates with higher surface charge and solubility compared to those produced via salt extraction. The EC values ranged between 476 and 542
g oil/g protein with LPI showing the highest capacity. Isoelectric-precipitated ChPI and LPI had relatively high surface charges (~−22.3
mV) and formed emulsions with smaller droplet sizes (~
1.6
μm), they also displayed high EAI (~
46.2
m
2/g), ESI (~
84.9
min) and CS (98.6%) results, which were comparable to the SPI.
► Emulsifying and physicochemical properties of protein isolates correlate strongly. ► Isoelectric-precipitated proteins showed good emulsifying properties. ► Chickpea and lentil proteins could serve as an alterative to soy – as emulsifiers.
► Microcapsule formation employing emulsion technology. ► Encapsulation of flaxseed oil in a legume protein–maltodextrin matrix. ► Microcapsule characterisation. ► Microcapsule release ...characteristics as a function of pH and ionic strength. ► Enhanced oxidative stability of microencapsulated flaxseed oil.
Flaxseed oil was microencapsulated, employing a wall material matrix of either chickpea (CPI) or lentil protein isolate (LPI) and maltodextrin, followed by freeze-drying. Effects of oil concentration (5.3–21.0%), protein source (CPI vs. LPI) and maltodextrin type (DE 9 and 18) and concentration (25.0–40.7%), on both the physicochemical characteristics and microstructure of the microcapsules, were investigated. It was found that an increase in emulsion oil concentration resulted in a concomitant increase in oil droplet diameter and microcapsule surface oil content, and a decrease in oil encapsulation efficiency. Optimum flaxseed oil encapsulation efficiency (∼83.5%), minimum surface oil content (∼2.8%) and acceptable mean droplet diameter (3.0μm) were afforded with 35.5% maltodextrin-DE 9 and 10.5% oil. Microcapsules, formed by employing these experimental conditions, showed a protective effect against oxidation versus free oil over a storage period of 25d at room temperature.
•Phenolic composition of three commercial Saskatoon berry varieties were determined.•TPCI and LC-MS were used to determine phenolic subclass and phenolic structures.•The Northline variety had the ...highest phenolic content and antioxidant activity.•Pomace from commercial juice production was a significant source of phenolics.•A saskatoon berry phenolic extract slowed the oxidation of borage oil by ∼65%
Total phenolic chromatographic indices (TPCI) of three commercially grown saskatoon berry varieties and a pomace from commercial juice production were determined. Northline was shown to have the highest TPCI of 504.2 mg/100 g FW. These results agreed with total phenolic content results for these varieties. The TPCI of the commercial pomace was 404.2 mg/100 g pomace indicating that a significant concentration of phenolics were present in this co-product, showing the commercial relevance of this material. A phenolic rich extract (PRE; 500 ppm) of the Northline variety was compared to BHT (0.02% w:w) and Rosamox (0.2% w:w) for delaying the oxidation of borage oil via rancimat analysis. Induction times were 1.46 h (borage oil), 1.44 h (Rosamox), 2.18 h (BHT), and 2.42 h (PRE), which was a ∼65% delay in the oxidation of borage oil. These results clearly support the value of this material as an antioxidant ingredient in foods, pharmaceuticals, nutriceuticals and cosmetics.
Turbidity measurements were used to study the formation of soluble and insoluble complexes between pea protein isolate (PPI) and gum arabic (GA) mixtures as a function of pH (6.0−1.5), salt ...concentration (NaCl, 0−50 mM), and protein−polysaccharide weight mixing ratio (1:4 to 10:1 w/w). For mixtures in the absence of salt and at a 1:1 mixing ratio, two structure-forming transitions were observed as a function of pH. The first event occurred at a pH of 4.2, with the second at pH 3.7, indicating the formation of soluble and insoluble complexes, respectively. Sodium chloride (≤7.5 mM) was found to have no effect on biopolymer interactions, but interfered with interactions at higher levels (>7.5 mM) due to substantial PPI aggregation. The pH at which maximum PPI−GA interactions occurred was 3.5 and was independent of NaCl levels. As PPI−GA ratios increased, structure-forming transitions shifted to higher pH.
Chlorogenic acids are among the most abundant phenolics found in the human diet. Of these, the mono-caffeoylquinic acids are the predominant phenolics found in fruits, such as apples and pears, and ...products derived from them. In this research, a comprehensive study of the electrospray ionization (ESI) tandem mass spectrometric (MS/MS) dissociation behavior of the three most common mono-caffeoylquinic acids, namely 5-O-caffeoylquinic acid (5-CQA), 3-O-caffeoylquinic acid (3-CQA) and 4-O-caffeoylquinic acid (4-CQA), were determined using both positive and negative ionization. All proposed structures of the observed product ions were confirmed with second-generation MS3 experiments. Similarities and differences between the dissociation pathways in the positive and negative ion modes are discussed, confirming the proposed structures and the established MS/MS fingerprints. MS/MS dissociation was primarily driven via the cleavage of the ester bond linking the quinic acid moiety to the caffeic acid moiety within tested molecules. Despite being structural isomers with the same m/z values and dissociation behaviors, the MS/MS data in the negative ion mode was able to differentiate the three isomers based on ion intensity for the major product ions, observed at m/z 191, 179 and 173. This differentiation was consistent among various MS instruments. In addition, ESI coupled with high-field asymmetric waveform ion mobility spectrometry-mass spectrometry (ESI-FAIMS-MS) was employed for the separation of these compounds for the first time. By combining MS/MS data and differential ion mobility, a method for the separation and identification of mono-caffeoylquinic in apple/pear juice samples was developed with a run time of less than 1 min. It is envisaged that this methodology could be used to identify pure juices based on their chlorogenic acid profile (i.e., metabolomics), and could also be used to detect juice-to-juice adulteration (e.g., apple juice addition to pear juice).
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•MS/MS behavior of three the most common mono-caffeoylquinic acids were determined.•Similarities and differences between the dissociation pathways in the positive and negative ionization are illustrated.•The MS/MS in the negative ion mode differentiated the three isomers based on product ion intensities.•ESI-FAIMS-MS/MS successfully separated the three isomers in juice samples with a run time of less than 1 min.
Flaxseed oil was microencapsulated employing a wall material matrix of either chickpea (CPI) or lentil protein isolate (LPI) and maltodextrin using a benchtop spray dryer. Effects of emulsion ...formulation (oil, protein and maltodextrin levels) and protein source (CPI vs LPI) on the physicochemical characteristics, oxidative stability, and release properties of the resulting capsules were investigated. Microcapsule formulations containing higher oil levels (20% oil, 20% protein, 60% maltodextrin) were found to have higher surface oil and lower encapsulation efficiencies. Overall, LPI–maltodextrin capsules gave higher flaxseed oil encapsulation efficiencies (∼88.0%) relative to CPI–maltodextrin matrices (∼86.3%). However, both designs were found to provide encapsulated flaxseed oil protection against oxidation over a 25 d room temperature storage study relative to free oil. Overall, ∼37.6% of encapsulated flaxseed oil was released after 2 h under simulated gastric fluid, followed by the release of an additional ∼46.6% over a 3 h period under simulated intestinal fluid conditions.
•4-O-p-Coumarylquinic acid was identified as a fingerprint phenolic in apple juice.•Isorhamnetin-3-O-rutinoside was identified as a fingerprint phenolic in pear juice.•Abscisic acid was identified as ...an additional fingerprint compound in pear juice.•Chromatographic differences were found between production regions in pear juice.
The ability to detect the undeclared addition of a juice of lesser economic value to one of higher value (juice-to-juice debasing) is a particular concern between apple and pear juices due to similarities in their major carbohydrate/polyol profiles. Fingerprint compounds for the detection of this type of adulteration were identified in both commercial apple and pear juices by HPLC-PDA, were isolated chromatographically, and structurally identified by LC-MS/MS. The apple juice fingerprint was identified as 4-O-p-coumarylquinic acid and two pear compounds as isorhamnetin-3-O-rutinoside and abscisic acid. Additionally, the HPLC-PDA profile of pear juices in combination with pear fingerprint compounds including arbutin could be used to identify samples originating from China versus those from other geographical locations.
The physical properties of lentil protein-based maltodextrin microcapsules with entrapped flaxseed oil was investigated using native (n-LPI) and pre-treated (heated, un-hydrolyzed (u-LPI); and ...heated, hydrolyzed (h-LPI)) lentil proteins and as a function of oil load (10, 20 and 30% of total solids). Specifically, the moisture, water activity, surface oil and entrapment efficiency (EE) were assessed, along with droplet size and emulsion morphology of all formulations. Moisture (<6%) and water activity (<0.2) of all capsules were characteristics of dried powder ingredients. Light microscopy imaging of the emulsions, revealed that the h-LPI had slightly larger oil droplets than the n-LPI and u-LPI, which both appeared similar. Findings were confirmed by light scattering, where droplet sizes were 6.7, 4.2 and 4.2μm for the h-LPI, u-LPI and n-LPI stabilized emulsions, respectively. Overall capsules prepared from h-LPI showed significantly higher surface oil and lower EE than both the n-LPI and u-LPI materials. Furthermore, as the oil content increased, overall surface oil became higher and EE became lower. Based on testing, capsules prepared using n-LPI with 10% oil loading was found to have the lowest surface oil content (~3.7%) and highest EE (~62.8%) for all formulations, and was subjected to an oxidative storage stability test over a 30d period vs. free oil. The encapsulation process proved to be effective at lowering the production of primary and secondary oxidative products than free oil.
•Entrapment unmodified lentil protein isolate led to the lowest surface oil.•Encapsulation protected the oil from oxidation compared to the free oil.•Partially hydrolyzed lentil proteins were not effective as an encapsulating agent.
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