Red Lakes: Cochineal and Logwood

Table of Contents

Red Lakes: Cochineal and Logwood
2015.October.19, 10:10am
Name: Cindy and Yuan (Kathryn and Siddhartha)
Date and Time:

2015.October.19, 10:10am

Location: Chandler 260
Subject:

Station 1

• pour ground cochineal into distilled water/potassium carbonate mixture (300ml)
• 
  
• 10:26 combined cochineal and distilled water/potassium carbonate with Kathryn and Siddhartha (now 600 ml) (now at Station 2)
  • 10:34 38 degrees C (Yuan)
  • 10:40 54 degrees C (Siddhartha)
  • 10:42 reduced heat to 3.5
  • 10:46 65 degrees C (Siddhartha) (seems to be going up 10 degrees every 5 min)
  • turned heat back up to 4.5
  • 10:50 cochineal water bat) begins boiling
  • 10:54 76 degrees C (Siddhartha)
  • 11:02 80 degrees C (Donna)
  • 11:03 turned heat back up to 5
  • Questions: we are using a water bath and we have combined two cochineal and water/potassium carbonate mixtures--does this mean it will take longer to heat?
  • 11:06 turned hot plate off to transfer mixture into a beaker so we can boil directly
    • can tell it has cooked down a bit, started will 600 ml, now about 520 ml
  • 11:10 76 degrees C, turned hot plate on again at 1 (boil about 5 min)
  • 11:15 77 degrees C, turned hot plate up to 1.5
  • 11:17 75 degrees C, turned hot plate up to 2
  • 11:19 turned hot plate up to 3
  • 11:22 split into two beakers, both beakers start boiling slightly
  • 11:26 both beakers 85 degrees C (Yuan), turned hot plate up to 4
  • 11:29 rolling boil in both beakers
  • 11:32 pour cochineal solution into jar through filter, solution now at 68 degrees C, dark purple translucent color somewhat like wine but more purple
  • 11:37 poured potash solution into cochineal solution while stirring, turned opaque magenta with effervescence, ammonia-like smell
  • 11:42 measured PH, about 5-6

• 10:41 add 10 g potash in 50 ml distilled water
  • Donna made a small handle out of wire for the beaker (to hold in water bath), small amount of water spilled
  • 10:48-10:53 Yuan held mixture in water bath while I stirred until potash crystals dissolved
  • meanwhile (around 10:50) the water bath around the cochineal mixture began boiling

• 11:45 start brazil wood recipe using logwood in 200 ml distilled water/potassium carbonate mixture, boiling on hot plate set at 3 in 250 ml beaker
  • unboiled logwood mixture the color of dark red wine
  • 11:50 48 degrees C (Siddhartha)
  • 11:58 started boiling, lower hot plate to 2
  • 12:04 turn hot plate up to 4 (brazilwood in larger 1000ml beaker has finished boiling and been taken off and filtered)
  • 12:10 rolling boil, turn hot plate back down to 1
  • 12:14 boiled to 150 ml, take off heat, filter into jar, 66 degrees C, deep blackish purple color
  • 12:16 pour potash/distilled water solution while stirring into logwood mixture, dark purple effervescence
  • cannot measure PH, color too deep and dyes PH strip

• 11:54 add 6 g potash alum in 50 ml distilled water
  • heat and stir on hot plate on 3
  • 11:58 fully dissolved (started to boil), take off hot plate

• 1:18 filtering logwood, liquid coming through very clearly, sediment left in filter
• 
  

---

ASPECTS TO KEEP IN MIND WHEN MAKING FIELD NOTES

• note time
• note (changing) conditions in the room
• note temperature of ingredients to be processed (e.g. cold from fridge, room temperature etc.)
• document materials, equipment, and processes in writing and with photographs
• notes on ingredients and equipment (where did you get them? issues of authenticity)
• note precisely the scales and temperatures you used (please indicate how you interpreted imprecise recipe instruction)
• see also our informal template for recipe reconstructions

---