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Discussion in 'In-Depth Kava Discussion' started by Bula Kava House, Sep 27, 2019.

  1. Henry

    Henry . Moderator The Kava Society of New Zealand

    From what I understood on the basis of my conversation with Dr Lebot and others, the exact chemotype determination is not really possible with this kind of device.
  2. Bula Kava House

    Bula Kava House Portland, OR Kava Vendor

    Not sure what Dr. Lebot's concern was, but it must have been worked out. I've seen the data and Kavalytics is VERY accurate for chemotype. It's validated at something like 95% accurate. It was developed based on HPLC results, in fact. Tyler sent hundreds of samples in for HPLC analysis to use as a baseline for comparative NIRS analysis. If you use HPLC to test an identical sample, it will have a result within a few hundredths or tenths of a percent of Kavalytics.

    Testing for non-noble blends is a little more nuanced since what defines a tudei or a noble isn't really properly defined. From Tyler: "Kavalytics is trained to ID mixes above 30% tudei, but it depends on how flagrant the mix is. Anymore we now just rely upon the actual analytics like kavain to DHM ratio, and flavokavain percentage (we don’t want above 0.25%). There’s all kinds of nobles, all kinds of tudeis and there’s no possible way to assign some percentage of tudei cutoff. Some noble like MOI is already at 0.2% (flavokavain) so a small amount of tudei makes it flag. Some tudei is real flagrant with high FK levels whereas others are almost noble. Lots of factors. The cutoff is that we don’t want material where K: DHM is below 1 or Flavokavains above 0.2-0.25. You can look at the analytics and know right away if borogu has 2-3x as much kavain and 0.15% FK, and to get something that’s 243, but with a K to DHM of 1.3 and FK of 0.275 that it’s a mix."

    Unfortunately, there still isn't a 100% accurate way to know the exact amount of tudei that may be mixed into your kava powder. Kavalytics is as good or better than anything we've seen yet to help figure it out though.
    Last edited: Oct 1, 2019
  3. verticity

    verticity I'm interested in things

    The Kavalytics web site states the the accuracy of the first 3 digits of the chemotype is 60%. But it does cite excellent accuracy for positive ID (100%), noble/tudei sorting (95%) and total kavalactones (84%):

    "KavaLytics™ 3.5 Model Features and Accuracy
    • Positively identify Kava – 100%
    • Determine if Kava is Noble or Non-Noble – 95%+
    • Provide total Kavalactone content - 84%+
    • Provide the first three numbers of the chemotype i.e. “4-2-3” - 60%+ (Beta)
    • Detect common adulterants of Kava including:
      • Excessive Peeled stems or “White Kasa” Content
      • Unpeeled stems or stem peelings or “Black Kasa”
      • Aerial stalks, stems, and leaves
      • Spent kava or “Makas”

    The concern was probably that in the NIRS studies that were done in the past (the paper by Gautz and another one by Lebot himself) they used instruments capable of measuring wavelengths between 400-2500 nm, and found that the region above 2000 nm was especially important for determining accurate chemotypes. The accuracy of individual KL measurements in Gautz's paper was about 90% relative to HPLC. The Kavalytics instrument can only detect NIR wavelengths between 900-1700nm, so a 60% accuracy for a partial chemotype makes sense to me based on working with half the NIR spectrum compared to those previous papers. Reproducing a result for an identical sample wouldn't tell you much. The real test would be completely different unknown samples.
  4. Gourmet Hawaiian Kava

    Gourmet Hawaiian Kava Kava Expert Kava Vendor

    I have a question about this, mentioned above that this can detect common adulterants like makas, how does it do that? How can it tell the difference from spent makas and the real makas that is supposed to be in there. Honest question here.
  5. Bula Kava House

    Bula Kava House Portland, OR Kava Vendor

    I didn't develop kavalytics and I'm not a data scientist, so I won't get too into the weeds here, but apparently, the 60% accuracy for chemotype is something of a technicality. Chemotypes as we know them are often separated by fractions of a percent. The same sample could test with ever so slightly different percentages and the first three numbers will completely switch. Having experience with HPLC, this is often the case as well. The same sample could be sent to three different labs, or even tested at the same lab, and you'll get three different chemotypes. The measurement of each individual kavalactone using kavalytics is very accurate.
    nashfire likes this.
  6. verticity

    verticity I'm interested in things

    I noticed on the web site that it says "Validated. Accepted by the Scientific Community as a Validated Method by Peer Reviewed Publication." This is in one of the scrolling images at the top. Thumbnail screenshot:

    2019-10-01 23_21_58-Kavalytics.png

    Which publication is this referring to? I would be very curious to read it if there is a pre-print or something available.
    Intrepidus_dux likes this.
  7. Kojo Douglas

    Kojo Douglas Kava Enthusiast

    This is why we can’t have nice things.
    nashfire, Kavashua and avahZ like this.
  8. nashfire

    nashfire Stay Rooted

    Eat, drink kava, and be happy!::tanoa::::KavaChug::::kavaleaf::
    The only kava I haven't really enjoyed I think may have been seriously fire-dried / super smokey strong flavor...but I still drank it...10 karat gold is still Gold to me!
    Kojo Douglas and JohnMichael like this.
  9. Kojo Douglas

    Kojo Douglas Kava Enthusiast

    This reminds me of a scene from one of the best American family films ever:

    nashfire likes this.