Changes

Jump to: navigation, search

Tetrahydropyridine

1,344 bytes added, 18:18, 10 June 2023
update to Detection Methods
Tempère et al. (2019) developed what they suggest is a better way to test for mousy off-flavor in wine via oral sensory, specifically as a way to enable panelists who are not as sensitive to THP to detect it during sensory testing. They compared the alkaline strips method to a method where the wine's pH is increased by adding sodium bicarbonate to a pH of 5 and a pH of 7. This mild base is contained in human saliva. At a pH of 5, sensory panelists were more easily able to detect APY and to correctly order the intensity of APY in wine than when they used alkaline strips. For example, the range of detection level for all panelists went from a range of 15 - 300 µg/L to a range of 0.3 - 30 µg/L. At a pH of 7, panelists were not as easily able to detect the aroma of APY. Keep in mind that this test does not reflect the real world tasting of wine since the pH would never be raised during normal consumption, but it could be used by a sensory program as a way to more reliably detect smaller amounts of APY in wine <ref name="Tempère_2019">[https://oeno-one.eu/article/view/2350 Comparison between standardized sensory methods used to evaluate the mousy off-flavor in red wine. Tempère, S., Chatelet, B., de Revel, G., Dufoir, M., Denat, M., Ramonet, P.-Y., Marchand, S., Sadoudi, M., Richard, N., Lucas, P., Miot-Sertier, C., Claisse, O., Riquier, L., Perello, M.-C., & Ballestra, P. 2019. DOI: https://doi.org/10.20870/oeno-one.2019.53.2.2350.]</ref>.
Other techniques for detected THP in food have been developed, which might be applicable to wine or beer. For example, Grimm Kiyomichi et al. (20012023) developed a technique for detecting 2simple method to accurately detect ATHP, ETHP, and APY using gas chromatography-acetyl pyrroline mass spectrometry with stir bar sorptive extraction (APY or 2APSBSE-GC–MS instrumentation) in rice. The rice samples had to be heated to 80-85°C in order to extract the volatile APY, Thermal desorption and then APY levels in the headspace of the rice container could be detected injection were performed using solid phase microextraction a Twisterthermal desorption unit (SPMETDU) and a Gerstel CIS 4 cooled injection system with a programmable temperature vaporization (PTV) inlet, installed on an Agilent 6890 gas chromatograph combined with fibers that operate an Agilent 5975 Mass Selective Detector (Agilent Technologies, Massy,France), equipped with a Gerstel MPS 2 autosampler (Gerstel, Mülheim an der Ruhr, Germany). An HP-5MS fused-silica capillary column (30 m × 0.25 mm, 0.25 µm, film thickness, SGE, Courtaboeuf, France) was used, with helium as carrier gas (Messer France S.A.S, Suresnes, France)at the higher temperatures a constant pressure of 70 kPa, corresponding to an initial flow of 1.3 mL.min−1 <ref>[https://www.ncbisciencedirect.nlm.nih.govcom/science/article/abs/pubmedpii/11170584 Screening for 2-acetyl-1S0308814623000705 Daiki Kiyomichi, Céline Franc, Pierre Moulis, Laurent Riquier, Patricia Ballestra, Stéphanie Marchand, Sophie Tempère, Gilles de Revel. Investigation into mousy off-pyrroline flavor in the headspace of rice wine using SPME/GCgas chromatography-MSmass spectrometry with stir bar sorptive extraction. Grimm CCFood Chemistry, Volume 411, 2023, Bergman C135454, Delgado JTISSN 0308-8146, Bryant Rhttps://doi.org/10.1016/j.foodchem.2023. 2001135454.]</ref>. It isn't known if such methods would also work for measuring THP compounds in beer or wine, but they could provide a potential option for beer and wine researchers.
Other techniques for detected THP in food have been developed, which might be applicable to wine or beer. For example, Grimm et al. (2001) developed a technique for detecting 2-acetyl pyrroline (APY or 2AP) in rice. The rice samples had to be heated to 80-85°C in order to extract the volatile APY, and then APY levels in the headspace of the rice container could be detected using solid phase microextraction (SPME) with fibers that operate at the higher temperatures <ref>[https://www.ncbi.nlm.nih.gov/pubmed/11170584 Screening for 2-acetyl-1-pyrroline in the headspace of rice using SPME/GC-MS. Grimm CC, Bergman C, Delgado JT, Bryant R. 2001.]</ref>. It isn't known if such methods would also work for measuring THP compounds in beer or wine, but they could provide a potential option for beer and wine researchers. Cider makers have used a baking soda in water solution to help detect THP. Dissolve a small amount of baking soda in water, swish the solution in your mouth for a few seconds, and then spit it out. While the pH of the saliva in your mouth is raised from the baking soda solution, taste the beer/wine/cider to more easily detect THP <ref>[https://groups.google.com/g/cider-workshop/c/a9JcCERQTYk?pli=1 "testing for mouse". Testing for Mouse. Retrieved 04/06/2021.]</ref>. The effectiveness of these methods in beer has not been reported to our knowledge (please report any research or anecdotes in the [https://www.facebook.com/groups/MilkTheFunk/ MTF Facebook group]).
===University of Southern Maine Methods===

Navigation menu