The attributes of D’limonene are compelling and are nature’s boost to cleaning. They include: biodegradable; 100% natural; derived from a by-product of orange peels crushed for juice; environmentally friendly solvent listed on EPA Safer Ingredients List; “Generally Recognized As Safe” rating from FDA; effective at degreasing; and pleasing citrus aroma. The combination of outstanding degreasing and fragrance is rare for any raw material. Either they clean or they provide a fragrance; not both.
D’limonene is a solvent that is not soluble in water. D’limonene is a great degreaser that is challenging and costly to formulate into a water-based product. To make d’limonene water-soluble, it requires at least four times more surfactant than d’limonene to create a clear solution in water. D’limonene is also expensive, so even if you could easily add it to a water-based product, why would you add to the cost of a typical pre-spray when it is not always necessary?
Based on these natural traits, it makes sense to formulate without water. Citrus boosters are the result of this common sense approach. The attributes of the best citrus boosters are also compelling. They include: great degreasing; phenomenal activity on removing tar, gum, adhesives, filtration soil, etc.; efficient as 1 to 2 ounces is enough to boost pre-spray efficacy; no impact on pH of solution; use food-grade d’limonene and orange oil for the ultimate natural orange scent; uses special surfactant to make it easier to add to pre-sprays, and extract with water, etc.
Add it as a booster where the need and extra expense is warranted. One to two ounces in a ready-to-use preconditioning agent provides a great fragrance and enough additional degreasing power when it is required. This limited amount will form a liquid solution as a result of the surfactants available in both the pre-spray and citrus booster.
I have heard it said often that any cleaning agent which needs “boosting” — or increasing the original strength of a product — is not a good cleaning agent. It can also be said that if you have an extremely soiled carpet and subsequently do not boost your cleaning agent for optimum performance, then you are not concerned about the best results and/or labor costs of the job. While there are varying opinions on this, we have seen several million pounds of citrus boosters sold over the years. Based on these facts, many, if not most, professional cleaners agree with the benefits of using citrus boosters— when needed.