What is Liquid Detergent Made Of? (and 15 Reasons Why it Matters)

Liquid detergent production by STPP Group - from laboratory to consumer

It has been a long road since the first soap bars appeared, and even longer since doing laundry indicated hard physical labor.

Animal fat-based detergents have been known since the 18th century, while synthetic detergents hit the market about 70 years ago. From that day forward, fresh innovations keep making our lives easier.

With the addition of enzymes, the idea of “stubborn stains” started to gradually disappear, but smudges of grease and hard water still caused a lot of headaches. And then came the liquid washing detergent.

In this article you can read about:

What is liquid washing detergent?

Laundry detergent is manufactured in two essential varieties: powder and liquid form.

While powdered detergents still hold a significant portion of the market, liquid detergents feature a set of advantages worth considering.

The term “Liquid detergent” is vague and refers to various types of cleaning products in liquid forms.

Apart from liquid laundry detergent, it also includes dishwashing liquid, hand soap liquid, a range of different household cleaners, and more.

All kinds of liquid detergents and related formulas (such as fabric softeners, e.g.) can be produced in the same plant.

What is liquid detergent used for?

Liquid detergent can be used for any kind of washing.

However, it delivers its best when used to clean oily stains, and/or in areas with hard water. It’s all about the formula – liquid detergents possess a higher ability to release and break down fat, and their ingredients are resilient to minerals typically found in hard water.

Moreover, liquid detergents are more suitable for washing colored fabrics, since many formulas preserve the hue better than powder detergents.

What it takes to make liquid detergent?

The simplest explanation of the liquid detergent manufacturing process is that all ingredients are blended and then if dry, liquidized. The latter requires a solubilizer, a solution composed of water and various chemicals.

STPP Group’s Liquid detergent production line
STPP Group’s Liquid detergent production line

How do you make high-quality liquid detergent?

The production can be manual, semi-, or fully automated.
Each process comprises similar essential steps:

1. Dosing and mixing major components – raw materials, creating a base

Liquid detergent ingredients come in dry or liquid forms. Following the desired formulation, they are measured and dosed into the homogeneous mixer and exposed to physical mixing and chemical reaction.

Typically, it means a neutralization reaction between LABSA and pre-dissolved Caustic soda.

2. Adding balancing components – pH adjusting, buffering, stabilizing the formula

After physical mixing, it’s time for thickeners, pH adjusters, and other balancing ingredients. Their addition is necessary in order to achieve desired viscosity, stability, and pH value.

3. Filtration – final perfecting of the liquid detergent product

The fully-mixed final detergent sits 5-12 hours in intermediate storage tankers. In this phase, the air bubbles and foam are removed and the product is ready for bottling.

4. Packaging and labeling

The bottling and capping process can be manual, semi-automated, and automated. A bottled liquid detergent is then labeled, branded, and finished. 

Finally, to make a liquid detergent, the blended mass of dry ingredients needs to be mixed with a solution consisting of water and solubilizers. The result is a viscous, transparent liquid ready for packaging.

Key takeaway

Liquid detergent is a useful alternative to powder detergents, especially in areas with hard water. It’s created by mixing the right proportion of the prescribed ingredients. The production process comprises several essential steps, from mixing the builders in a base to adding a range of perfectors.

What are the ingredients in liquid laundry detergent?

There are plenty of detergent brands on the market, and each manufacturer has its own formulas.

Although most of the essential ingredients are often the same, it’s the proportion and small details that affect the finished product’s performance and its ability to clean well. 

Here we will pass through the standard list of ingredients, necessary to create a good washing detergent formula.

Alkaline Builders: A Base

You might have heard that the old ways of doing laundry included using weird agents such as ash and lye. In fact, those agents are not weird at all. They are simply – alkalies.

Alkaline builders make the essential component in the majority of laundry detergents. It’s the base, typically composed of soluble salts that react with acids in order to neutralize them.

Alkalies are the magic that helps you to remove stains and dirt from the clothes without endless rubbing. 

Alkalis, however, feature no wetting properties on their own and need to be combined with surfactants. The cleaning power of the final formula heavily depends on the right proportion of ingredients, as this study shows.

The first soaps and detergents contained plant ashes as the base. Modern versions are mainly composed of caustic soda (sodium hydroxide) or caustic potash (potassium hydroxide). These alkalies are chemically produced by running electricity through the salty water.

Caustic soda samples - pearls & flakes
Caustic soda samples – pearls & flakes

Alkaline substances feature different strengths, and the most potent ones can even damage fabrics. For instance:

  • Gentle alkali is sodium bicarbonate (baking soda)
  • Medium-strength alkali is borax, often used in DIY cosmetics as an emulsifier and buffering agent with the ability to soften hard water and suspend soap particles. Other examples can be household ammonia and sodium tripolyphosphate (STPP).
  • Potent alkalies are lye (caustic soda) and sodium carbonate (washing soda).

If you want to be sure that your washing detergent contains alkalies (although it’s least probable that it doesn’t), look for ingredients like potassium or sodium in the ingredient list printed on the package.

Surfactants: The Foamers

Have you seen a washing detergent that is not foaming?

Although the pioneering attempts to create effective non-foaming formulas produced some successful results, the bubbles are still a crucial part of cleaning processes. And that’s why we need surfactants. 

Surfactants are the second major component of washing detergents. Apart from enhancing the foaming ability of the formula, they also break up stains and disperse the dirt that doesn’t dissolve in water.

Anionic surfactants contain negatively charged molecules that help them remove dirt and greasy stains.

However, they don’t perform well in hard water. Minerals, such as magnesium and calcium, react with anionic surfactants, preventing them from working properly. 

If you live in an area with hard water, better look for a liquid detergent with a non-ionic surfactant. Their molecules have no electrical charge. Alternatively, try a combination of anionic surfactants to complement and boost cleaning action.

  • Anionic surfactants: alkyl sulfates, alkyl ethoxylate sulfates
  • Non-ionic surfactants: fatty alcohols or ethers
Linear Alkyl Benzene Sulfonic Acid (LABSA) sample
Anionic surfactant sample – LABSA – provided by STPP Group

If you want to know what surfactants are contained in your favorite detergent brand, look at the ingredients list. 

Suppose you find ammonium lauryl sulfate, sodium laureth sulfate, sodium lauryl sulfate, alfa olefin sulfonate, sodium myreth sulfate, sodium pareth sulfate, sodium lauryl sarcosinate, or ammonium laureth sulfate. In that case, your washing detergent is powered by anionic sulfates. 

Cocamide monoethanolamine (cocamide MEA), cocamide diethanolamine (cocamide DEA), fatty alcohol ethoxylates, amine oxides, and sulfoxides indicate the presence of non-ionic surfactants.

Catalytic Enzymes: The Superheroes

Enzymes are the silent superheroes that changed the laundry detergent industry for good.

Different enzymes target specific soils, and the catalytic action breaks the soil into smaller molecules to be washed away.

Each class of detergent enzyme provides particular benefits to make the laundry detergent formula more efficient.

What they have in common is shortening washing time, also allowing washing and lower temperatures. That way, they also minimize water and electricity consumption, making the formulas more environmentally friendly.

Additionally, enzymes produced by fermentation technologies support the use of renewable resources.

  • Protease: Works well against protein-based soils, improving detergent efficiency. Great for household laundry detergents used at a lower temperature, and lower pH levels.
  • Amylase: Its role is to degrade starch-based or carbohydrate soils. Similar to protease, it’s improving detergent efficacy at lower temperatures and pH levels.
  • Cellulase: Releases soils by breaking down cotton fibers, which results in the rejuvenated appearance of washed items.
  • Lipase: Great in degrading greasy, oily, fat-based stains. Other performances are similar to protease and amylase. 
  • Mannanase: Best when used against food-based stains, ideal for washing kids’ clothes. 
  • Pectinase: Efficiently dissolves vegetable- and fruit-based stains.

Proteases were the first enzymes ever used in the mass production of laundry detergents. Over time, lipases and amylases joined to support the performances and environmental protection levels of the detergent formula.

Enzymes can reduce an environmental load of detergent products as the chemicals used in conventional detergents are reduced, as presented by Academic Journals in this study. They are biodegradable, non-toxic, and leave no harmful residues.

The new generation of washing detergents introduced industrial biotechnology or “white biotech.” It’s based on upgrading enzyme cells and their components in order to generate improved, industrial-strength laundry detergents with exceptional sustainability and eco-friendliness.

PH Modifiers: The Balancers

The role of pH modifiers is balancing acids and bases in water to create an optimal washing environment. The “pH” stands for “potential of hydrogen” and measures the level of acidity or alkalinity.

When chemical ingredients are dispersed in water, the mixture’s pH level defines whether it’s an acidic, alkaline, or neutral compound.

For example, with a pH level of 7.0, pure water is neutral. Also, you might remember the ads promoting cosmetic products with pH 5.5 – that’s the pH of human skin. Slightly acidic, it presents the first barrier against germs and external aggressors.

Acid and basic are two extreme ends of the pH scale.

  • Mineral-acid cleaner: It belongs to the pH range of 0-2, suitable for cleaning heavy oxide scales.
  • Mild acid cleaner: With pH 2-5.5, it works well against inorganic salts and water-soluble metal complexes
  • Neutral cleaner: The pH scale of 5.5-8.5 defines neutral compounds, such as glass cleaners. It’s useful against light oily stains and small particles of dirt. 
  • Mild alkaline cleaner: The pH level of 8.5-11 is efficient against all kinds of greasy stains, standard for powerful grease-cutting dishwashing liquids.
  • Alkaline cleaner: Harsher variety with pH 11.5-12.5 is the enemy of heavy fats and proteins.

Highly alkaline cleaner: Often featured in cleaners with bleach and chlorine, pH 12.5-14 is potent against soils but bad for skin/fabrics.

Optical Brighteners: Alternative to Bleach

Optical Brightener sample provided by STPP Group
Optical Brightener sample provided by STPP Group

Optical brightening agents (OBAs), also called “fluorescent whitening agents (FWAs),” and “fluorescent brightening agents (FBAs),” improve the appearance of whiteness on the fabrics.

When we say “on,” – it’s not a typo. The optical brighteners protect the fibers by eliminating the need for traditional, harsh bleach.

Instead, they work on the surface to absorb ultraviolet light. Reflecting in the blue region results in an effect of improved whiteness, or better said – brightness. 

Textile fibers absorb optical brighteners from the formula, so they don’t rinse out. Once deposited, even at low levels, they keep improving the visual quality of the fabric.

Optical brighteners already existing in fabrics get progressively removed by successive washes, but at the same time, they get replaced by OBAs from the detergent.

Other supporting ingredients

  • Water conditioners – used to manage hard water and inhibit dye transfer
  • Suds – take control over surfactants activity to prevent excess foaming
  • Preservatives – work to prevent microbial growth.
  • Fragrances – enhance the effect of “cleanliness” and improve the sensory value of the formula.
  • Dyes, colorful speckles – enhance the appeal of the formula, helping with visual identity.

PRO tip: If you have sensitive skin, opt for detergents with no dyes because dermatologists have found that dyes in detergents are the main cause of skin irritation.

Key takeaway

A good detergent formula relies on several vital points. Alkali base is essential, but its cleaning power is low without surfactants. Catalytic enzymes are superheroes that simplify the washing process, making it diverse and easy. pH modifiers stabilize the formula in a range ideal for the best-targeted performance. Finally, a range of enhancers defines the finished washing detergent, easily identified by its customers.

15 common questions about liquid detergent formulas

As manufacturers, we face many questions from our clients and customers. As transparent suppliers who believe in shared knowledge as a path to progress, we are happy to provide the answers.

Here we have gathered a collection of the most frequently asked questions about liquid detergents, from those who genuinely depend on the correct answers: the end consumers.

Is there animal fat in liquid laundry detergent?

It depends on the manufacturer and the formula. On average, liquid detergents do feature animal fat, sometimes in high concentrations.

Does liquid detergent damage washing machines?

If everything works properly, then the risk of any serious damages to the washing machine is minuscule to none.

However, if animal fats contained in most liquid detergents do not dissolve properly, they may clog up lines and solenoid valves.

It will cause them to drip and pile up inside the machine over the years, leading to other issues. However, those problems typically require only minor fixes and thorough cleaning of all components. 

In short, the possibility of liquid detergent causing any harm to the washer, or draining system, is very low.

Does liquid detergent cause mold?

In certain instances, liquid detergents may turn your high-efficiency washing machine into a breeding ground for mold. This happens more often with the frequent cold-water setting.

Here’s what to do to prevent it from happening:

– Wipe the damp parts of the washing machine after use.
– Leave the lid open to lighten and ventilate the washer, creating an environment that prevents mold from growing.
– Take all wet clothes out as soon as the washer has finished.
– Regularly clean the seals and gaskets of front-load washers.

Does liquid laundry detergent clog pipes?

Although liquid detergents typically do not clog pipes, there is a slightly increased risk of clogging. It’s significantly lower, though than with powdered detergents.

The key to prevent clogging from happening is to thoroughly read and follow the instructions for use, including recommended dosage for one load.

Proper dosing is especially important when using high-performance, ultra-concentrated detergent liquids.

What is the harm of liquid detergent?

There is a minimal chance that liquid detergent will cause any substantial harm to your washer or the drainage system.

However, if the washing machine already has a problem, it may get worse after a while.

Also, in washers that don’t drain instantly, such as front loaders, animal fat from the liquid detergent dissolved in residual water might cause some unpleasant smells.

How do you make liquid detergent at home for commercial use?

We don’t recommend trying to make a liquid detergent at home for commercial use.

Also, it’s almost impossible. Producing a commercial-grade liquid detergent requires very specific equipment and environment.

DIY liquid detergents are not likely to get all licenses and approvals necessary for commercial use.

Finally, making detergents at home is not safe, especially without proper, professional training.

Still, that doesn’t mean that you have to give up the idea of making your own brand of detergent. There are other, simple and convenient options such as private labeling.

Private Labeling service by STPP Group

Many independent companies offer such services, along with others like contract manufacturing. That means they possess all the equipment needed to produce quality, detergent licensed formulas, and, even better – the knowledge and experience to do it right. 

Using contracting services such as private labeling might, in the end, prove more affordable and more stable investment than trying to establish something from scratch. Especially if you don’t possess the proper knowledge and tools.

What is the best liquid detergent?

The best choice of liquid detergent is the one that fits your needs.

It should be effective on various types of soils or perhaps targeting some specific issues. Then, there are some personal preferences such as form, appearance, fragrance, and last but not least- value and price.

Suppose that your most frequent laundry task is washing lightly-soiled clothes with a few or no stains. In that case, any average quality liquid detergent may suit your needs.

On the other hand, if your family is highly active and toddlers keep changing several times a day, you probably need a versatile, heavy-duty, high-quality detergent in mega-packs.

Make sure to check the ingredient list, compare it with our ingredients guide, and find the formula that suits your needs. 

Also, if you prefer to wash in cold water, opt for a specialized liquid detergent for the best results.

Check out the concentrated formulas. They come in smaller, more convenient packaging, but offer the same performance as the standard versions – just with a smaller single dose.  

If you want more information on how to select the best detergent, our friends from Spruce wrote some words about it.

Is liquid detergent better than powder?

That depends on what you consider as “better.” Liquid detergent offers similar performances as powder detergent, but it’s more efficient in hard water and against grease.

Is liquid detergent better than powder for washing machines?

Liquid detergent has some advantages over powder detergent, and those are most prominent in the field of washer safety.

Powders contain more chemicals than liquids, and their residue causes more problems in septic tanks. At the same time, liquid detergents are already pre-dissolved and do not pile up in the draining system.

The only problem with liquid detergents is that overdosing may result in foam leaks and similar issues.

Is liquid detergent the same as fabric softener?

The answer is no.

Liquid detergent and fabric softeners are often packed in a very similar manner and placed together on supermarket shelves.

However, they serve entirely different functions. The purpose of detergent is to clean fabrics by removing dirt and stains. The fabric softener rejuvenates and protects the fabric during the process.

Can you put liquid detergent directly in the washer?

You may put liquid detergent straight on your dry clothes, ready for washing. That can sometimes help with removing heavy stains.

Can I put liquid detergent in the drum or directly on clothes?

You can pour the dose of liquid detergent directly into the drum, on top of the laundry, but there is a slight possibility that it won’t dissolve properly. 

One thing to consider, though, is never just to pour the liquid detergent into the empty drum. It will leak and get lost inside the machine before getting a chance to do the job.

Can liquid detergent be used in the front load washer?

The answer to this depends on the machine model and manufacturer’s instructions. Some models are made for use with powder detergent only.

Is liquid detergent better than pods?

Liquid detergent is convenient, versatile, and comes in a broad range of scents and targeted options.

Pods have one advantage – they are packed as pre-measured portions eliminating the risk of overdosing.

However, that kind of convenience also comes with a cost: it requires a lot of plastics. If you are environmentally conscious, a large bottle of liquid detergent is probably a better solution.

Is liquid or powder detergent cheaper?

There are many detergents on the market, and the price range is huge.

Depending on the brand and the formula, you might find both cheap and pricey versions of both powder and liquid detergents.

However, liquid detergent often comes in highly concentrated formulas that cover dozens of washing loads with a similar price tag as the standard packages.

Key takeaway

Liquid detergents bear a whole lot of advantages that will give you great laundry results. It’s powerful enough to remove tough stains with a single washing cycle, without any adverse effects on fabric quality or bright colors. The most stubborn stains can be pre-treated by pouring liquid detergent straight to the spot before loading the washer. Moreover, liquid detergent poses a minuscule threat to the health of your washing machine, since it dissolves better than powders at lower temperatures. Finally, liquid detergents outperform powders in hard water.

Bottom line

Liquid detergents bear a whole lot of advantages that will give you great laundry results. Choosing the right set of ingredients can greatly enhance your washing results if you tailor them according to your needs and the region you live in. We hope we have managed to help you get there. 

If you have any specific questions or you are thinking about starting your own detergent production, our experts are ready and available 24/7.