Strawberry purée
Label appeal: a soap made with a favourite fruit or vegetable. Soap Queen supplier or guide
Opens the calculator’s starter recipe, 1000 g of oils, with this additive at the dose it fills in, ready to change.
What it is
Raw strawberries, puréed: mostly water, with some sugar and some citric and malic acid.
USDA FoodData Central primary source, USDA FoodData Central primary source
How much
- 0.97–1.94 oz per pound of oils filled in (from a published recipe that adds it to one part of the batch: the lower figure over the whole batch, the higher within that part) Cable, The Natural Soap Making Book for Beginners primary source
- up to 6 % of the batch Fisher, The Complete Photo Guide to Soap Making primary source
The calculator fills in 0.97 oz per pound of oils: 60.6 g for the 1000 g of oils in its starter recipe.
When and how
- Usually: at light trace.
- Blend it smooth first.
Cable, The Natural Soap Making Book for Beginners primary source, Fisher, The Complete Photo Guide to Soap Making primary source
What it does to the recipe
- Every 100 g takes 0.56 g of sodium hydroxide, which the calculator adds to the lye.
- 90.95 % is water, taken off the recipe’s water.
- 0.3 % is fat, which stays in the bar as extra superfat.
- 4.89 % is sugar, which heats the batch.
USDA FoodData Central primary source, USDA FoodData Central primary source, Stoichiometry primary source
Worth knowing
- About 0.9 % of it is fruit acid, mostly citric, and the calculator adds the lye that acid takes. USDA FoodData Central primary source, Stoichiometry primary source
- Caution: It heats the batch: work cool and do not insulate it, or it can crack or overflow the mould. Cable, The Natural Soap Making Book for Beginners primary source
- Caution: Blend it smooth: pieces left in the bar can spoil. Fisher, The Complete Photo Guide to Soap Making primary source
- It darkens the soap, to tan or brown. Lovely Greens supplier or guide
Spoons and drops
- 1 tsp ≈ 4.83 g
- 1 tbsp ≈ 14.5 g
- 1 cup ≈ 232 g
USDA FoodData Central primary source
INCI name
Fragaria Ananassa Fruit
- CAS number
- 1175540-74-5
Guides that discuss it
Sources
Soap Queen, purées in soap: "natural purees in bath and beauty products are fantastic from a marketing standpoint. Who doesn’t want a bar of soap made with their favorite fruit or veggie?"; "a strawberry puree will add extra sugar and water. Using an avocado puree will add extra fats and water"; pumpkin purée gives "a very gentle orange color", and in one soap "turned a soft orange hue"; at thin trace; "adding too much puree could cause mold and bacteria growth".
USDA FoodData Central, food 167762: Strawberries, raw (1 cup, pureed = 232 g).
USDA FoodData Central, food 2263887: Strawberries, raw (citric acid 699.8 mg, malic acid 198.1 mg per 100 g).
Neutralisation stoichiometry with IUPAC 2013 molar masses: grams of NaOH per gram = protons × 39.997 ÷ molar mass. Disodium EDTA dihydrate (372.24 g/mol) takes 2; sodium bicarbonate (84.007 g/mol) 1; magnesium sulfate heptahydrate (246.47 g/mol) 2; borax decahydrate (381.37 g/mol) 2, to sodium metaborate; malic acid (134.087 g/mol) 2; citric acid (192.124 g/mol) 3. An acidity given in milliequivalents per litre takes that many millimoles of NaOH per litre.
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.
David Fisher, The Complete Photo Guide to Soap Making (Creative Publishing International, 2018), p. 113: "keep the additives to no more than 5 or 6 percent of the soap’s total weight—or 1 ounce (28 g) per 1 pound (454 g) of soap"; "If you leave chunks of fruit or other additives in the soap, they are likely to turn rancid or moldy, or both". P. 114, cucumber purée soap: "Though it contains more than 95 percent water"; it "adds a lovely natural pastel yellow-green color"; the purée replaces "half the lye-water" and is added to the batter at light trace.
Lovely Greens, herbs and dried flowers in soap: "I tend to use 1-3 tsp of plant material per pound (454 g) of soap. One teaspoon for dense material, like poppy seeds, and three teaspoons for fluffier herbs, like calendula petals"; "Calendula flower petals don’t discolor in soap recipes"; "rose petals will turn rusty brown wherever they touch soap, and almost every herb turns dark brown when mixed in"; lavender, "Inside the soap, the buds turn brown"; "most fruit and vegetable juices or purees will turn your soap brown or fade to an unexciting tan or yellow"; "Botanicals can soften, mold, and rot if kept in moist or humid places"; "Too many dried seeds or herbs stirred in can feel scratchy or stop the soap from lathering properly".