In this study we show that a nonaqueous capillary electrophoresis mass spectrometry (NACE-MS) method carefully optimized by a design of experiment can be applied to a very large number of alkaloids in different plant extracts. It is possible to characterize the pattern of the psychoactive alkaloids in several plant samples and preparations thereof, each presenting different challenges in their analysis. The method is shown to be able to separate structurally closely related substances, diastereomers and further isobaric compounds, to separate members of different alkaloid classes within one run and to tolerate significant matrix load. A comparison with methods presented in the literature reveals that a near-generic NACE-MS method for the fast profiling of alkaloids in forensically relevant plant samples has been developed.

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Maple sap is a complex nutrient matrix collected during spring to produce maple syrup. The characteristics of sap change over the production period and its composition directly impacts syrup quality. This variability could in part be attributed to changes in tree metabolism following dormancy release, but little is known about these changes in deciduous trees. Therefore, understanding the variation in sap composition associated with dormancy release could help pinpoint the causes of some defects in maple syrup. In particular, a defect known as “buddy”, is an increasing concern for the industry. This off-flavor appears around the time of bud break, hence its name. To investigate sap variation related to bud break and the buddy defect, we monitored sap variation with respect to a dormancy release index (Sbb) and syrup quality. First, we looked at variation in amino acid content during this period. We observed a shift in amino acid relative proportions associated with dormancy release and found that most of them increase rapidly near the point of bud break, correlating with changes in syrup quality. Second, we identified biological processes that respond to variation in maple sap by performing a competition assay using the barcoded Saccharomyces cerevisiae prototroph deletion collection. This untargeted approach revealed that the organic sulfur content may be responsible for the development of the buddy off-flavor, and that dormancy release is necessary for the appearance of the defect, but other factors such as microbial activity may also be contributing.

Buddy maple syrup is characterized by an unpleasant cabbage‐like flavor occurring generally toward the end of the sap harvest season. Occurrence of buddy off‐flavor leads to a decrease in syrup value and economic loss for the industry. It is therefore relevant to characterize the off‐flavor in order to apply corrective treatments. HS‐SPME combined with GC/MS was applied to analyze volatile aroma compounds in buddy maple syrup samples. Two novel volatile sulfur compounds were found in maple syrup: dimethyl disulfide (DMDS) and dimethyl trisulfide. A 3‐alternative forced choice in ascending concentration of different buddy syrups diluted in good quality syrup was conducted in triplicate to assess buddy syrup concentration thresholds leading to detection and recognition of the off‐flavor by 16 panelists while monitoring volatile aroma compounds in diluted samples. Results showed that DMDS was associated with the flavor defect. The recognition threshold concentration of buddy syrup varies depending on the syrup sample and the off‐flavor can be detected in syrups containing very low DMDS content. Application of a continuous heat treatment on buddy syrups for 2 hr at 104.5 °C led to a removal of the buddy off‐flavor as well as a significant reduction in DMDS content. Practical Application The results of this study provide a better understanding of the buddy off‐flavor in maple syrup and the heat treatment applied allowed us to eliminate this defect and obtain a syrup with a better sensory quality.

In this project, samples of osmosed maple saps were demineralized to 12.5 and 25% levels by electrodialysis (ED). The effect of this treatment on the composition and the physicochemical and sensory properties of maple syrups obtained from demineralized maple sap was evaluated. The ED technology was efficient to decrease levels of malic acid and calcium in osmosed maple saps. Effectively, 38% and 24% decreases in malic acid and calcium respectively were reached for ED with a demineralization level of 25% without any changes in the other measured components of osmosed maple saps. The demineralization process had no effect on the yield of syrups produced and on their characteristics: no significant difference was observed during sensory analysis and viscosity. Moreover, the percentage of light transmission of syrups produced from demineralized osmosed saps was higher than for the control. This work suggests that ED could be a potential technology to decrease or avoid sugar sand formation during maple syrup production.