Bread is one of the most widely consumed foods in the world. Among the different properties that define its quality, the aroma of bread is considered essential to its approval by consumers. Knowing ...what the compounds found in bread are, as well as the most important ones in crumb and crust, and understanding their biological sources and how they affect the final aroma of bread, could make it possible to modify the steps of bread manufacturing in order to enhance those with a positive impact and reduce those with a negative impact. The aim of this review is to provide a guideline correlating a great deal of the information now available regarding wheat bread aroma. For this purpose, a total of 326 volatile compounds reported in the literature have been included. The sensorial correlation of these compounds with the final aroma of wheat bread has also been explained, as well as the biological sources that generate them. Finally, it is shown how modifying the production stages of wheat bread could also affect the odour quality.
•A guideline with the available information of wheat bread aroma is provided.•A total of 326 volatile compounds in crumb and crust are collected in a table.•The biological origin of these compounds has been reviewed in crumb and crust.•The main factors that affect the final aroma of bread are shown.•The impact of these volatiles on the aroma perceived by consumers is presented.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Wine fermentation processes are driven by complex microbial systems, which comprise eukaryotic and prokaryotic microorganisms that participate in several biochemical interactions with the must and ...wine chemicals and modulate the organoleptic properties of wine. Among these, yeasts play a fundamental role, since they carry out the alcoholic fermentation (AF), converting sugars to ethanol and CO
together with a wide range of volatile organic compounds. The contribution of
, the reference organism associated with AF, has been extensively studied. However, in the last decade, selected
strains received considerable commercial and oenological interest due to their specific pro-technological aptitudes and the positive influence on sensory quality. This review aims to highlight the inter-specific variability within the heterogeneous class of non-
in terms of synthesis and release of volatile organic compounds during controlled AF in wine. In particular, we reported findings on the presence of model non-
organisms, including
spp. and
, in combination with
. The evidence is discussed from both basic and applicative scientific perspective. In particular, the oenological significance in different kind of wines has been underlined.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Lignin, the second most abundant biopolymer, is a promising renewable energy source and chemical feedstock. A key element of lignin biosynthesis is unknown: how do lignin precursors (monolignols) get ...from inside the cell out to the cell wall where they are polymerized? Modeling indicates that monolignols can passively diffuse through lipid bilayers, but this has not been tested experimentally. We demonstrate significant monolignol diffusion occurs when laccases, which consume monolignols, are present on one side of the membrane. We hypothesize that lignin polymerization could deplete monomers in the wall, creating a concentration gradient driving monolignol diffusion. We developed a two-photon microscopy approach to visualize lignifying Arabidopsis thaliana root cells. Laccase mutants with reduced ability to form lignin polymer in the wall accumulated monolignols inside cells. In contrast, active transport inhibitors did not decrease lignin in the wall and scant intracellular phenolics were observed. Synthetic liposomes were engineered to encapsulate laccases, and monolignols crossed these pure lipid bilayers to form polymer within. A sink-driven diffusion mechanism explains why it has been difficult to identify genes encoding monolignol transporters and why the export of varied phenylpropanoids occurs without specificity. It also highlights an important role for cell wall oxidative enzymes in monolignol export.
The use of polyols as sugar replacers in bakery products is a common practice. In these products, pasting and gelation properties of starches have a strong influence on the process and on the quality ...of final products. In this study, the influence of different polyols (maltitol, sorbitol, xylitol and mannitol) on pasting properties of two starches (wheat and maize) was analysed and compared to those made only from native starches and their combinations with sucrose. Rheological properties of gels as well as their texture and colour were also analysed. Even though differences among the different studied polyols and the interactions among them and among starches were observed, in general polyols showed an influence on starch properties similar to those of sucrose. Thereby, in general peak viscosity and setback as well as gel hardness were increased and L* was reduced with the use of polyols. In all cases, the polyol which showed more similar results to those made from sucrose was maltitol. Meanwhile, xylitol was the polyol which modified the native starch properties to a lesser extent, both in RVA curve, especially in the cooling stage, and in gel rheology and hardness.
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•Paste and gel properties of different sucrose/polyol–starch combinations were studied.•In general polyols showed an influence on the starch properties similar to sucrose.•The polyol which showed results more similar to those of sucrose was maltitol.•Xilytol was the polyol which modified the native starch properties to a lesser extent.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Losses of volatile compounds during baking are expected due to their evaporation at the high temperatures of the oven, which can lead to a decrease in the aroma intensity of the final product, which ...is crucial for gluten-free breads that are known for their weak aroma. Volatiles from fermentation and lipids oxidation are transferred from crumb to crust, and they flow out to the air together with Maillard and caramelisation compounds from the crust. In this study, the release to the oven of volatile compounds from five gluten-free breads (quinoa, teff and rice flours, and corn and wheat starches) and wheat bread during baking and toasting was measured in real-time using proton transfer reaction-time of flight-mass spectrometry (PTR-ToF-MS). Baking showed different volatile release patterns that are described by bell-shaped curves, plateaus and exponential growths. Flour-based breads had the higher overall volatile release during baking, but also high ratios in the final bread, while starch-based breads showed high pyrazine releases due to moisture losses. Meanwhile, toasting promoted the release of volatile compounds from the bread matrix, but also the additional generation of volatiles from Maillard reaction and caramelisation. Interestingly, gluten-free breads presented higher losses of volatiles during baking than wheat bread, which could partially explain their weaker aroma.
•Effect of pulsed light (3, 6, and 9 J cm-2) on blueberry quality were investigated.•Slight loss in antioxidant activity and total soluble solids were observed.•At 6 J cm-2 firmness, titratable ...acidity increased, but weight loss decreased.•Pulsed light can maintain blueberry quality and enhance post-harvest shelf-life.
Blueberry consumption has been a burgeoning interest attributed to their nutritional and health benefits. However, the main limitation to blueberry marketability is their perishability due to water loss, fungal, and mechanical damage during post-harvest preservation. In this study, pulsed light (PL) treatments with doses of 3, 6 and 9 J cm-2 were applied in the 6-week storage of highbush blueberry (cv. Draper) at 0.5°C under 90-95% relative humidity (RH) conditions. The quality changes of berry were assessed by using physicochemical attributes and antioxidant activity bi-weekly at week 0, 2, 4, 6. The results show that in spite of the partial loss of the antioxidant activity and total soluble solids (TSS), PL at dose of 6 J cm-2 was found to increase firmness and titratable acidity (TA), and decrease weight loss, rot incidence, and pH during post-harvest storage, which lead to a better maintenance of blueberry quality and shelf-life extension.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Societal impact statement
Plant biodiversity is fundamental to the future of food security and agriculture. Berries are the most economically important fruit crops in Canada. Within this article, we ...explore the nutritional, cultural, and botanical importance of berries, including crop wild relatives (plant species that are closely related to domesticated crops) and plants that are significant to Indigenous Peoples. Using berries as a case study, we explore opportunities for the conservation, use, and public engagement of crop wild relatives. Our objective is to lay the groundwork for future collaborative efforts across these diverse plants.
Summary
Conservation of plant biodiversity, in particular crop wild relatives including those tended and cultivated by Indigenous Peoples, is critical to food security and agriculture. Building on the 2019 road map for crop wild relatives, we examine berries as a case study for crop wild relative conservation, use, and public engagement. We focus on berries due not only to their economic, cultural, and nutritional importance but also because they are consumed fresh, providing a unique opportunity for individuals and communities to connect with plants. We outline health benefits, geographic distribution, and species at risk for Canadian berries. We describe practices, strategies, and approaches used by Indigenous Peoples to steward berries and emphasize the importance of traditional knowledge. We highlight opportunities for in situ and ex situ berry conservation and use of berries in plant breeding and Indigenous foodways. Our aim is to lay the groundwork for future collaborative efforts in these areas and to showcase berries as a useful case study for conservation of food plant biodiversity and public engagement.
Plant biodiversity is fundamental to the future of food security and agriculture. Berries are the most economically important fruit crops in Canada. Within this article, we explore the nutritional, cultural, and botanical importance of berries, including crop wild relatives (plant species that are closely related to domesticated crops) and plants that are significant to Indigenous Peoples. Using berries as a case study, we explore opportunities for the conservation, use, and public engagement of crop wild relatives, with the objective of continuing to expand efforts across these diverse plants.
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DOBA, FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UILJ, UKNU, UL, UM, UPUK
Pulsed light (PL) is a novel, non-thermal technology being used to control the microbial spoilage of foods and beverages. Adverse sensory changes, commonly characterized as "lightstruck", can occur ...in beers when exposed to the UV portion of PL due to the formation of 3-methylbut-2-ene-1-thiol (3-MBT) upon the photodegradation of iso-α-acids. This study is the first to investigate the effect of different portions of the PL spectrum on UV-sensitive beers (light-colored blonde ale and dark-colored centennial red ale) using clear and bronze-tinted UV filters. PL treatments with its entire spectrum, including the ultraviolet portion of the spectrum, resulted in up to 4.2 and 2.4 log reductions of
in the blonde ale and centennial red ale beers, respectively, but also resulted in the formation of 3-MBT and small but significant changes in physicochemical properties including color, bitterness, pH, and total soluble solids. The application of UV filters effectively maintained 3-MBT below the limit of quantification but significantly reduced microbial deactivation to 1.2 and 1.0 log reductions of
at 8.9 J/cm
fluence with a clear filter. Further optimization of the filter wavelengths is considered necessary to fully apply PL for beer processing and possibly other light-sensitive foods and beverages.
•HPLC-QTOF method was validated for determining 31 phenolic compounds in blueberries.•ESI (+) mode led to MS/MS fragmentation patterns common for the same chemical group.•PCA phenolic groupings ...agreed with the seasonal phenology of blueberry cultivars.•Malvidin-3-O-galactoside and chlorogenic acid were the most abundant free phenolics.•Syringic acid was the most abundant bound phenolic, being highest in ‘Duke’.
Blueberry consumption has increased in recent years, partially due to the health benefits attributed to their phenolic content. This study aimed to optimize and validate a high-performance liquid chromatography/quadrupole-time of flight mass spectrometry (HPLC/QTOF-MS) methodology for the determination of free (i.e., solvent extractable) and bound (i.e., covalently bound to the plant cellular structures) phenolics in northern highbush blueberries. A total of 31 phenolics, including anthocyanins, flavonols, flavan-3-ols, and phenolic acids, were targeted in the positive electrospray ionization mde ESI (+), including MS/MS confirmation of their product ions. Free phenolics determination was validated in terms of sensitivity, reproducibility, linearity, and accuracy, and 21 free phenolic compounds were found above their limits of detection among six commercial blueberry cultivars, which were quantified with correction for the matrix effect. ‘Elliott’ presented the highest free phenolic and anthocyanin contents (3640 and 3430 mg kg−1 fresh weight, respectively). Malvidin-3-O-galactoside was the most abundant free phenolic for ‘Duke’, ‘Draper’, ‘Elliott’, and ‘Last Call’ while chlorogenic acid predominated for ‘Bluecrop’ and ‘Calypso’. Syringetin-3-O-glucoside was the most abundant bound phenolic compound among the six blueberry cultivars.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
•SPME-GC/MS method was validated for determining 73 volatiles in blueberries.•Sensitivity, reproducibility, linearity, and accuracy of the method were evaluated.•Duke, Draper, Bluecrop, Calypso, ...Elliott, and Last Call volatiles were quantified.•Linalool and 2-(E)-hexenal concentrations distinguished the six blueberry cultivars.•(+)-Linalool and (−)-limonene predominate for the six blueberry cultivars.
Blueberry aroma is one of the most important quality traits that influences consumer purchasing decisions. This study aimed to optimize and validate a solid-phase microextraction-gas chromatography/mass spectrometry (SPME-GC/MS) method for the quantification of 73 volatile compounds in northern highbush blueberries. A SPME extraction of blueberries with water and specific proportions of sodium chloride, citric acid, and ascorbic acid, for 60 min at 50 °C using a divinylbenzene/carboxen/polydimethylsiloxane (DVB/CAR/PDMS) fiber was optimal. The method was validated for sensitivity, reproducibility, linearity, and accuracy, and used to quantify volatile compounds through matrix-matched calibration curves in six blueberry cultivars (‘Duke’, ‘Draper’, ‘Bluecrop’, ‘Calypso’, ‘Elliott’, and ‘Last Call’). Terpenes represented the most abundant volatile fraction, followed by aldehydes and alcohols. Linalool and 2-(E)-hexenal were key compounds that differentiated blueberry cultivars via Principal Component Analysis (PCA). Enantiomeric analyses revealed an excess of (−)-limonene, (−)-α-pinene, and (+)-linalool for all cultivars with potential impacts on the blueberry aroma.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP