A café notices its lattes look paler this month. A manufacturer’s ice cream base drifts yellow. A brand’s tin, reordered from the same supplier, tastes more astringent than the launch batch. Nothing was “wrong” with the supplier; the harvest changed, the blend was adjusted, or the powder aged. Consistency in matcha is achievable, but only if both sides work at it.

01 · Why lots vary

Sources of variation

  • Harvest year and weather: sweetness, color and yield differ between years
  • Field and cultivar mix: blends change as lots run out
  • Harvest timing: earlier or later picking within the same season
  • Processing: steaming, drying and sorting differences between factories
  • Milling: method, mill condition, heat and moisture; see particle size and milling
  • Age: time since milling and storage conditions; see shelf life and bulk storage

02 · How suppliers manage it

How good suppliers manage consistency

Suppliers who supply beverage chains and manufacturers manage variation deliberately:

PracticeWhat it does
Tencha inventory across fields and yearsGives blenders room to hit a target
Blending to a referenceEach blend adjusted against a retained standard
Cold storage of tencha, milling to orderPowder is fresh at shipment
Color and sensory checks per lotCatches drift before shipping
Particle size checksKeeps texture and suspension stable
Lot recordsEnables traceability when a question arises

Ask candidates which of these they do. Suppliers who cannot describe a process will struggle to deliver consistency at scale; see tea farm, factory or trading company.

03 · Buyer side

What buyers must do

Consistency is a shared responsibility. On the buyer’s side:

  • Keep sealed retained samples of the approved reference and of every lot received
  • Write a specification with color reference, taste description, particle size and test panel
  • Approve each production lot against the reference before shipment where possible, or on arrival with a defined window
  • Record dose adjustments, sensory notes and photos per lot
  • Store powder correctly after arrival so you do not create drift yourself
Retained samples settle arguments

When a lot seems different, the conversation is quick if both parties can compare against the same sealed reference. Without it, it is opinion against opinion.

04 · Harvest change

Managing the annual harvest change

Every year there is a moment when the new harvest replaces the old. Ask suppliers how they handle the transition: a blended crossover, an early sample of the new-year lot, or a straight switch. Plan a formal re-approval of the reference each year, and update your reference sample when the new harvest is accepted. The supply calendar shows when this usually happens.

05 · Contract

Writing consistency into the agreement

Specification, reference samples, lot approval and what happens when a lot misses belong in a supply agreement, however short; see what to put in a matcha supply agreement.

06 · Support

Handling issues on the Japan side

Consistency issues are best raised quickly, in Japanese, with the retained samples in hand. Our quality and documentation service does that with your supplier and helps set up lot approval so the next lot arrives right.

07 · FAQ

Frequently asked questions

Why does my matcha taste different from the last order?

Harvest year, field and cultivar mix, milling and age all cause variation, and powder that has sat in stock fades. Compare the new lot with your sealed retained reference, check the milling date, and raise the difference with the supplier promptly.

Can a supplier guarantee identical matcha every lot?

Not identical — it is an agricultural product — but a supplier with tencha inventory, blending to a reference and per-lot checks can keep a grade within a tight, agreed tolerance.

What is lot approval?

A step where you receive a sample of the actual production lot, compare it with the reference and any test results, and approve it before shipment. It catches drift while it is still the supplier’s problem to fix.

Japan-side support

Having consistency problems with a supplier?

Send us the specification, retained samples and the issue. We raise it with the supplier in Japanese, agree corrective steps and set up lot approval going forward.

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