Cinnamon, ground

David Fisher, The Complete Photo Guide to Soap Making (Creative Publishing International, 2018), p. 20: dyes "give a full range of hues—from subtle to bright and bold", but "can bleed between layers or swirls of soap, especially in melt-and-pour soap. Some are not stable in cold process soap, so test them first"; oxides "are very stable and strong in soap". Natural colours, pp. 82–84. In an infused oil: "Annatto: yellow-orange"; "Alkanet: light to deep purple, depending on the amount used"; "Paprika: orange-peach". In the lye solution: "Indigo: light to deep blue"; "Madder root: pinkish-red"; "Rose clay: deep rose pink". Added to the oils or at trace: "Activated charcoal: light gray to deep black"; "Black walnut hull (ground): speckled brown, also an exfoliant"; "Calendula flower petals (whole or ground): nice, warm yellow"; "Carrots (puréed or juiced): muted orange"; "Cinnamon: reddish tan to brown"; "Cocoa powder: tan to brown"; "Cucumber: pale yellow-green"; "Rosehips (ground): speckled reddish brown"; "Sage: muted green"; "Spirulina: pastel green/blue-green". For "a bright, white bar of soap": "Add titanium dioxide: about 1 teaspoon per 1 pound (454 g) of oils."

Kelly Cable, The Natural Soap Making Book for Beginners (Althea Press, 2017): "Replacing 25 percent of the water with juice gives the bar a more golden color without browning or causing sugar difficulties"; most juices "turn a dark color within the soap, typically brown"; juices frozen "to a slush" before the lye; "when adding purées, always remove the same weight in water"; 2 ounces of puréed strawberries at light trace for 33 oz of oils, all of it in half of the batch, where "the sugars from the purée can cause this soap to possibly overheat"; "Beet root powder starts off a pretty, bright pink, but when added to soap, it turns brown"; "most herbs turn brown when added at trace. If you want to avoid this, add them to the top of your soap right before it sets"; "Make sure your herbs are very dry before adding them to the soap, as moisture left within herbs can bleed into the soap over time, leaving a brown halo". "Green can be made with spirulina, comfrey leaf, and parsley leaf". Activated charcoal: "Add 1 teaspoon per pound of soap". Recipes, per 31–35 oz of oils: "2 tablespoons ground turmeric" blended into the whole batch (32 oz), and "3 teaspoons ground turmeric" in one of four equal parts (31 oz); "2 teaspoons woad powder" and "1 tablespoon white kaolin clay", each in one of three equal parts (34 oz); 1 tablespoon of dried nettle leaf, or 2 tablespoons; 1 tablespoon of ground cinnamon; 1 tablespoon of dried peppermint flakes, "plus more to sprinkle on top"; 1 tablespoon of steeped chamomile flowers at light trace and 2 on top; comfrey, "1 heaping tablespoon comfrey leaf powder" infused in 8 ounces of olive oil, 3 ounces of that oil in the recipe.

Susan Miller Cavitch, The Natural Soap Book (Storey Publishing, 1995), chapter 5, pp. 53–54: "Powdered cinnamon is a favorite, but try cloves, nutmeg, and allspice as well. The soaps they produce are speckled and range anywhere from a caramel color to a dark chocolate. Curry powder and turmeric yield shades of yellow and peach"; "Cayenne pepper and paprika create beautiful, salmon-colored soaps"; "first beat it into a small amount of the soap mixture or into a tablespoon of avocado or olive oil"; "Experiment with the desired degree of color, from 1 tablespoon (15 ml) of spice up to ¼ cup (59 ml). If you increase the amount up to ½ cup (118 ml) for a 12-pound (5.45 kg) batch of soap, you run the risk of spicy lathers and a heavy-duty cleanup job." Her batches are 12 pounds, so 1 tablespoon to ¼ cup is 0.25–1 teaspoon per pound of soap.

Lovely Greens, natural soap colorants: cinnamon, "use up to 1 tsp ground cinnamon powder PPO. Be aware that cinnamon leaves a slightly gritty feeling"; beetroot, "Warm to dull brown", "Unfortunately, beets do not color CP/HP soap red"; black walnut hull powder, "Add powder at trace and be aware that they create a scratchy or exfoliating texture"; red sandalwood, "Add 1/4-1/2 tsp powder PPO at trace after premixing in a little oil. Can be very scratchy if you use more than this"; woad, "Add 1-2 tsp powder PPO to the lye solution"; rose hips, "Up to 1 tsp ground rosehip powder PPO"; nettle leaf, "muted green", "Premix dried and powdered nettle leaf with a little water and add at trace. Use 1-3 tsp PPO"; kelp, "Dark green", "at trace at up to 3 tsp PPO. Pre-mix in an equal amount of distilled water"; sage, "muted green that fades with time", or "1 tsp PPO dried sage at trace for dark speckles"; peppermint, "1 tsp PPO finely ground peppermint leaves at trace"; liquid chlorophyll, "stunning greens from using about 1 TBSP PPO", fading "into a greeny-yellow"; cucumber, "initially green but usually fades to a muted yellow"; chamomile, "Infuse flowers in distilled water and use the strained liquid to make the lye solution"; green tea, "Brown-green"; rhassoul clay, "Brown"; French green clay, "pale pastel green to earthy green"; "plant-based greens tend to be fugitive". PPO is per pound of oils.

P. V. Rao and S. H. Gan, "Cinnamon: a multifaceted medicinal plant", Evidence-Based Complementary and Alternative Medicine (2014) 642942, Table 1: cinnamon bark oil, "Cinnamaldehyde: 65.00 to 80.00%".

Scientific Committee on Consumer Safety, Opinion on fragrance allergens in cosmetic products, SCCS/1459/11 (2012): List A, "Fragrance chemicals, which according to existing knowledge, are most frequently reported and well-recognised consumer allergens", includes cinnamal, coumarin, eugenol and isoeugenol.

Regulation (EC) No 1223/2009, Annex III, entries 71 (eugenol) and 76 (cinnamal), as amended by Regulation (EU) 2023/1545: the substance must be named in the list of ingredients "when its concentration exceeds ... 0,01 % in rinse-off products". Both have been named allergens since Directive 2003/15/EC.

EU: Regulation (EC) No 1223/2009, Article 14(1)(c), a product may contain as colourants only those in Annex IV. US: 21 CFR Part 73 Subpart C lists the colour additives for cosmetics, and turmeric, paprika and spirulina are listed for food only; under 21 CFR 701.20 a true soap, sold only as soap, is not a cosmetic.

USDA FoodData Central, food 171320: Spices, cinnamon, ground (1 tsp = 2.6 g; 1 tbsp = 7.8 g).