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Vineyard exposure to wildfire smoke can taint grapes and wine. To understand the impact of this taint, it is imperative that the analytical methods used are accurate and precise. This study compared the variance across nine commercial and research laboratories following quantitative analysis of the same set of smoke-tainted wines. In parallel, correlations between the interlaboratory consensus values for smoke-taint markers and sensory analyses of the same smoke-tainted wines were evaluated. For free guaiacol, the mean accuracy was 94 ± 11% in model wine, while the free cresols and 4-methylguaiacol showed a negative bias and/or decreased precision relative to guaiacol. Similar trends were observed in smoke-tainted wines, with the cresols and glycosidically bound markers demonstrating high variance. Collectively, the interlaboratory results show that data from a single laboratory can be used quantitatively to understand smoke-taint. Results from different laboratories, however, should not be directly compared due to the high variance between study participants. Correlations between consensus compositional data and sensory evaluations suggest the risk of perceivable smoke-taint can be predicted from free cresol concentrations, overcoming limitations associated with the occurrence of some volatile phenols, guaiacol in particular, as natural constituents of some grape cultivars and of the oak used for barrel maturation.

Purpose: Rising atmospheric CO2 levels associated with climate change increase plant nutrient demands. However, few studies have examined the interactions of atmospheric CO2 and P supply on root exudation which plays a crucial role in mobilising non-labile P in soil. This study aimed to examine the interactive effects of elevated CO2 and P deficiency on root exudation of organic acid anions and sugars over time. Methods: White lupin (Lupinus albus L.) was grown at 1, 5 and 50 µM P in solution culture under ambient (380 ppm) and elevated (700 ppm) CO2 levels. Root exudates were collected after 3, 4, 5 and 6 weeks of treatment, and organic acid anions and sugars were quantified using liquid chromatography-mass spectrometry. Results: Elevated CO2 and P deficiency positively interacted to enhance citrate exudation between 3 and 5 weeks of growth, while malate was only sporadically affected by elevated CO2 and fumarate remained unaffected. Elevated CO2 also increased exudation of glucose and fructose with larger increases being observed in P-deficient plants, which was largely constrained after 4 weeks. Elevated CO2 had no effect on exudation rates as plants matured. Conclusion: The positive interaction between CO2 and P deficiency led to increases in organic acid anion and sugar exudation, indicating that rising atmospheric CO2 levels could allow plants to access greater amounts of non-labile P when faced with P deficiency thereby reducing their reliance on non-renewable fertiliser inputs. [ABSTRACT FROM AUTHOR]

Abstract: Bovine milk is considered to be a good dietary source of vitamins A, E and β-carotene. This paper describes a robust method for the simultaneous determination of these compounds using high performance liquid chromatography–ion trap mass spectrometry (HPLC–MS n ) as the determinative step. The compounds were separated with a 5μm Polaris 2.1×150mm C18-A column and an aqueous-methanol mobile phase and the levels determined using the MS2 fragments (vitamin A, m/z 213 and m/z 199, vitamin E m/z 165 and β-carotene m/z 413). The HPLC–MS n was operated in the positive ion APCI mode. The method was validated using repeatability studies, duplicate analyses, recovery experiments, proficiency study data and comparison with previously validated high performance liquid chromatographic ultraviolet/visible (HPLC–UV/Vis) and fluorescence (HPLC–Fl) procedures used in our laboratory. Expanded measurement uncertainties were similar for HPLC–MS n , HPLC–UV/Vis and HPLC–Fl, e.g. vitamin A 45μg/100ml, HPLC–MS n ±8%, HPLC–UV ±9%; vitamin E 150μg/100ml, HPLC–MS n ±11%, HPLC–Fl ±9%; β-carotene 12μg/100ml, HPLC–MS n ±18%, HPLC–Vis ±21%. [Copyright &y& Elsevier]

Abstract: A renewed international interest in vitamin D status has revealed significant deficiencies in several populations, including Australia. Vitamin D exists in two forms, cholcalciferol (D3) and ergocalciferol (D2). The main source of vitamin D3 is from exposure of 7-dehydrocholesterol present in the skin to UV irradiation. However, there is an absolute requirement for vitamin D through proper dietary intake if humans live in the absence of sunlight or exclusively indoors. Bovine milk is considered to be a good dietary source of vitamin D3, even though the levels are quite low. This paper describes robust methods using liquid chromatography–linear ion trap mass spectrometry (LC–MSn) and liquid chromatography–tandem mass spectrometry (LC–MS/MS) to measure the levels of vitamin D3 in fresh bovine milk (0.05μg/100ml), commercial (natural and fortified) milk samples (0.01–2μg/100ml) and a dairy based infant formula (8μg/100g), without the need for extensive clean-up procedures. The limits of quantification (LOQ) are 0.01μg/100ml and 0.02μg/100ml for LC–MSn and LC–MS/MS, respectively. Recoveries of vitamin D3 added to the samples prior to saponification were satisfactory (range 60–90%). 25-Hydroxyvitamin D3 was not present in any of the samples analysed (LOQ=0.01μg/100ml, recovery range 30–40%). [ABSTRACT FROM AUTHOR]

This study investigated the impact of feeding pelleted diets containing camelina ( Camelina sativa L. Crantz) hay (CAHP) or camelina meal (CAMP) as a supplement compared with a control pellet (CONP) diet, without vitamin E fortification. The fatty acid profile, retail colour, and lipid oxidative stability of lamb and yearling meat ( m. longissimus lumborum ) stored for short-, medium-, or long-periods (2 days (fresh), 45 days and 90 days) under chilled to semi-frozen conditions were determined. The CAMP diet altered key fatty acids ( p < 0.05) in a nutritionally beneficial manner for human health compared to the other diets, with increased total omega-3, decreased omega-6 fatty acids and decreased omega-6/omega-3 ratio of muscle. Muscle vitamin E concentration was lower ( p < 0.05) for both camelina diets (CAMP and CAHP) when compared with the CONP diet, with the average concentrations less than 1 mg/kg muscle for all three treatments. Animal type and storage length were factors that all affected ( p < 0.05) colour and lipid oxidative stability of meat. These results emphasise the importance of vitamin E concentration in meat stored for extended periods under semi-frozen conditions to maintain desirable meat colour during retail display, and to avoid off-flavour development of the cooked meat.