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Teas & Tisanes

Background

In the technical sense, true tea is made exclusively from the Camellia sinensis plant, whereas herbal teas (or tisanes) are infusions made from other botanical ingredients.

A variety of traditional herbal teas can be wild-harvested or sourced in the Northeast United States:

This project aims to discover how traditional tea-making techniques and wisdom can be applied to a variety of local herbs, spices, vegetables, and fruits in the Northeast to produce delicious, complex, tea-like beverages.

Many local plants are traditionally used fresh or simply dried, which limits their aromatic potential. Applying techniques like withering, controlled oxidation, or microbial fermentation can break down glycosides and cell walls, releasing complex volatile compounds, organic acids, and savory amino acids that are otherwise inaccessible.

A common challenge in non-alcoholic pairings is the lack of body, astringency, and length on the palate. By manipulating tannin extraction, enzymatic browning, and roasting (such as toasting or char-roasting), we can build additional mouthfeel and complexity.

This framework allows us to utilize invasive species like Japanese Knotweed or underutilized agricultural byproducts (such as the leaves of Red Raspberry or orchard prunings) to create high-value pantry items. It shifts the focus from imported commodities to a resilient, hyper-local beverage culture.

Tea Classifications

Non-Grain Herbal Teas

  • Infusions of wild or cultivated leaves, roots, flowers, fruits, barks, needles, seeds, and fungi.
Leaf Teas
  • Nettle
  • Red Raspberry Leaf
  • Fireweed
  • Mint
  • Lemon Balm
  • Catnip
  • Skullcap
  • Verbena / Vervain
  • Yarrow
Flower Teas
  • Chamomile
  • Linden
  • Elderflower
  • Clover
  • Meadowsweet
Fruit / Berry Teas
  • Rose Hip
  • Elderberry
  • Hawthorn
  • Staghorn Sumac
Root / Rhizome Teas
  • Dandelion
  • Burdock
  • Valerian
  • Japanese Knotweed
  • Kudzu
Bark / Twig Teas
  • Spicebush
  • Birch
  • Sassafras
Needle Teas
  • Pine
  • Spruce
Seed / Spice Teas
  • Caraway
  • Spicebush Berry
Fungal Teas
  • Chaga
  • Reishi

Grain Teas

Roasted Grain Infusions
Popped / Cooked Grain Teas

Notes and Observations

Extraction and Brewing Dynamics

Brewing techniques dictate which volatile compounds enter solution. Temperature and agitation heavily influence the final profile:

  • Hot Brews: High temperatures extract bitter compounds more rapidly. Over-extracting or brewing too long at high temperatures leads to harsh bitterness.
  • Cold Brews: Cold Brewing avoids extracting many of these bitter compounds, yielding a milder, often cleaner flavor profile.
  • Solvent Extraction: While water is the standard solvent, other mediums can capture different aromatic profiles. As Harold Mcgee notes in On Food and Cooking: “They do infuse herbs in watery vinegar and in alcohols, but both alcohol and vinegar’s acetic acid are small cousins of fat molecules, and help dissolve more aromatics than plain water could.” This principle is highly relevant when managing flavor extraction in ferments like kombucha, wherein acetic acid contributes to the dissolution of flavor compounds.

Enzymatic “Fermentation” and Oxidation

In traditional tea-making, the term “fermentation” historically refers to enzymatic Oxidation rather than microbial activity.

  • The Process: Tea makers bruise or press the leaves to rupture cell walls, exposing cell contents to oxygen and activating polyphenoloxidase.
  • The Chemistry: Polyphenoloxidase links simple polyphenols into longer chains, which progressively darken the leaves and reduce bitterness and astringency. This oxidation process liberates complex aromas from their sugar-bound precursors.
  • Temperature Tolerance: Because black tea has undergone this extensive enzymatic oxidation, it can tolerate high-temperature brewing without becoming overly bitter. Green tea, which is unoxidized, retains its highly reactive, bitter compounds and must be brewed at lower temperatures to prevent harshness.

Tea is naturally mildly acidic, slightly bitter, and contains trace salts. It is also rich in theanine, a unique amino acid that contributes sweet and savory (umami) notes. During processing, theanine partially breaks down into glutamic acid, further enhancing the savory character of the brew.

Herbal teas can often be elevated by borrowing processing methods from traditional tea production:

  • Oxidation: Bruising and oxidizing non-tea leaves to alter their flavor profile (e.g., Blue Hill’s Apple Blossom Tea).
  • Fungal Fermentation: Utilizing microbes to age and transform botanicals, mimicking the Pu’er tea process (e.g., Nordic Food Lab’s research into non-tea fermentations).

Processing Techniques

Traditional tea processing is generally understood as a sequence of steps. For example, black tea quality is highly dependent on plucking, withering, rolling, oxidation parameters (time, temperature, humidity), drying, and storage. We can adapt these steps into a reusable processing vocabulary for local botanicals:

  • Withering: Controlled moisture loss to soften tissue and initiate aroma development.
  • Bruising / Rolling / Maceration: Rupturing cell walls to expose enzymes to oxygen.
  • Fixing / Kill-Green: A heat step (steaming or pan-firing) to deactivate enzymes and halt enzymatic oxidation.
  • Oxidation: Enzymatic browning and polyphenol transformation to darken leaves and round out harsh flavors.
  • Roasting / Toasting: Applying dry heat to develop Maillard, caramel, nutty, or cereal notes.
  • Smoking: Introducing wood smoke for phenolic aromas and preservation.
  • Char / Roast-Darkening: Deep roasting techniques suited for roots (dandelion, chicory, burdock) and grains.
  • Microbial Fermentation: Utilizing lactic acid bacteria, yeasts, acetic acid bacteria, or molds to drive biochemical transformations.
  • Aging: Slow, long-term oxidation and microbial/enzymatic changes under controlled dryness.

Sources

  • Harold McGee, On Food and Cooking (pp. 413, 416)
  • Blue Hill – Apple Blossom Tea oxidation techniques
  • Nordic Food Lab – “Tea, But Not” (exploration of Pu’er-style fungal fermentation on local botanicals)

In this project

Black Oat Koji Tea

The cold-brewed black oat koji has a slightly cherry-like, fruity, and chocolatey taste, which extracted nicely. The oats have lost all of their black color, an...