Love Soylent 1.5; but I'm really frustrated with variations in taste

Over the last month or so, I’ve been enjoying Soylent 1.5 for lunch. It gives me basic nutrition during a busy time of my day.

However, I’ve noticed something odd that’s happened in about 20% of my batches: occasionally it tastes completely different from the taste I’ve come to know and love. My lot number is L5133.

From time to time, I’ve found that I end up with an overwhelmingly sweet blend (rather than having mild sweetness mixed with a hint of savory goodness). It’s especially noticeable in the aftertaste. I’m not sure what is causing this, so I wanted to get some ideas from the community.

I’ve been racking my brain for possible reasons for my inconsistent experience. Here is my shortlist of possibly related factors, which I haven’t thoroughly evaluated yet:

  1. Production differences: for some unknown reason, is the end product not similar enough between bags?
  2. Preparation differences: cold water mixed with hot water? Add powder, then water, then powder, etc or add all powder then water?
  3. Different amounts of clumps forming: From time to time I’ve noticed visible chunks of dry powder when preparing, prompting me in some cases to mix with a spatula.
  4. Variations in amount of water added: Is a difference in the amount of water I’m adding causing significantly different taste?
  5. Different pitchers: I switch back and forth between the standard Takeya pitcher and a 2L Frigoverre Jug with Hermetic lid (I tend to prefer this one). Could this be prompting me to add different levels of water?
  6. Contamination from cleaning: Are bits of soap not getting rinsed off on my pitchers? Are my sponges not clean enough? Is there any residue from my drying towels that are introducing a change in taste?
  7. Sealing the pitcher: When leaving a batch to chill overnight (as I always do), should the pitcher be fully sealed or allow a bit of air to come in?

Here’s a confusing tidbit to add to the mix: I did an experiment where I made a batch in my Frigoverre pitcher, poured about 250mL into the Takeya pitcher, then left both pitchers overnight in the refrigerator. Just as a test, I left the Takeya pitcher completely unsealed. In the morning, I sealed the Takeya pitcher, shook it, and then poured it into a glass. Delicious. Then I shook and poured a bit of Soylent from my other pitcher: it tasted terrible.

Anyway, now that I’ve articulated the above points I’ll be trying to watch out for them in relation to my Soylent.

I’m also curious to see if anyone has any more suggestions to add on how to keep the taste more consistent.