Enzymes – the biggest question of trust among all boilie ingredients
“Enzymes in boilies” is currently one of the biggest trends in the carp scene — and at the same time one of the most misunderstood terms of all. Many anglers – and some manufacturers too – have no clear idea what enzymes are, how they work and under which conditions they function.
That makes enzymes the biggest question of trust among all boilie ingredients — for a reason that doesn’t apply in this form to any other topic: with poor raw ingredients you buy poor quality. With enzymes, that’s not enough of an explanation. Here a manufacturer can use top-quality raw ingredients — and wipe out the entire enzymatic effect with a single processing mistake. The result looks like a good boilie, smells almost like one, and is biochemically useless.
You can’t see it. You can barely smell it. You can’t test it. You have to trust the manufacturer — or understand the biochemistry yourself. This article gives you the knowledge you need to do both.
What enzymes are – the scientific basis
Enzymes are biocatalysts — protein molecules that speed up biochemical reactions without being used up themselves. They lower the activation energy of a reaction and make processes possible that wouldn’t happen without them or would take years.
What matters is their task specificity (substrate specificity): every enzyme fits one very specific molecule like a key. A protein splitter (protease) splits proteins — but not fats. A starch splitter (amylase) splits starch — but not protein. The term “enzymes in boilies” without further detail tells you as much as “medicines” without saying which ones. The question is always: which enzyme, for which target substance (substrate), under which conditions?
Important up front: according to Arlinghaus (2002), enzymes themselves are not attractants for carp — their value lies in what they produce: water-soluble amino acids, simple sugars and fatty acids. It’s these breakdown products that carp detect and respond to. How amino acids, betaine and other breakdown products work as attractants in the bait is explained in the article Boilie attractants – amino acids, betaine and DMPT.
The three enzyme classes that matter for carp baits
Proteases – the key to the attraction cloud
Proteases split proteins into shorter peptides and finally into free amino acids. Biochemically, this is the most important process for a boilie’s attraction.
Complete protein molecules are too large to dissolve quickly in water. Single amino acids and short peptides, on the other hand, are water-soluble and diffuse immediately. Carp detect them via specialised chemoreceptors in the mouth, lips and barbules. For carp, the signal profile of free amino acids is the biochemical equivalent of “real food here”. Free amino acids rank second in the attractant hierarchy according to Arlinghaus (2002) — right after natural extracts from invertebrates.
Protease sources in practice:
- Papain — from papaya sap. One of the most potent natural proteases. Used industrially as a meat tenderiser. In boilies: breaks down fishmeal and liver proteins. Only active in fresh or gently dried form.
- Bromelain — from pineapple. A protease with a similar effect to papain. Fresh pineapple juice is active as a liquid — industrially processed, heated pineapple juice no longer contains active bromelain.
- Microbially produced proteases — from Bacillus subtilis, Aspergillus oryzae. Produced industrially, very efficient, optimised for specific pH ranges.
- Pre-digested protein solutions (hydrolysates) — fish hydrolysate, squid hydrolysate, krill hydrolysate, liver hydrolysate. The enzyme process is already complete — free amino acids are present, the product is heat-stable and can go straight into the base mix.
Amylases – turning starch into attractant
Amylases split polysaccharides — complex carbohydrates such as starch — into simple sugars (maltose, glucose). That matters for boilies because starch is insoluble in water: a boilie with lots of wheat or maize flour releases hardly any soluble attractants from its starch content. Amylase-treated starch, on the other hand, delivers instantly water-soluble sugars that diffuse into the water.
The same mechanism explains why fermented grains are so effective: yeasts and bacteria produce amylases during fermentation that break the starch down into sugar. The enzymatic route is faster and easier to control.
Natural amylase source: raw, unheated honey contains diastase (an amylase). Heated honey no longer contains active enzymes.
Lipases – an important difference from oils
Lipases split fats (triglycerides) into glycerol and free fatty acids. An important distinction is needed here: according to Arlinghaus (2002), oils and fats have no attractant effect on carp — they’re insoluble in water and barely detectable by the carp’s chemoreceptors themselves. Oil does, however, carry flavours and forms an oil film from which water-soluble attractants are released.
The benefit of lipase lies elsewhere: phospholipid-bound fatty acids, as in Krill Esterblend, disperse much better in water than pure triglycerides thanks to enzymatic splitting — they emulsify better and spread more evenly in the water. That improves the physical distribution of other water-soluble attractants in the mix. Lipases are therefore more structure improvers than direct attractants.
The most critical point: boiling destroys all enzymes
It’s a mistake many anglers – and some manufacturers – make — and it explains why many enzyme boilies don’t live up to their promise.
Enzymes are proteins. At temperatures above 60–70°C they start to denature — their three-dimensional structure collapses and they lose their catalytic function. At 100°C (the boiling temperature for boilies), all natural enzymes are completely and irreversibly destroyed within minutes. The same applies to steamed boilies – the comparison boiling or steaming boilies shows why.
Consequence: enzymes that go into the boilie paste and are boiled straight away are useless afterwards – the end product no longer contains any active enzymes. It’s only different with a targeted paste treatment: if the enzymes get enough time in the paste before boiling, their breakdown products (free amino acids, sugars) stay in the boilie after boiling. On top of that, overheating or too long a cooking time brings in the Maillard reaction: amino acids form insoluble compounds with carbohydrates, and the availability of the attractants drops (Arlinghaus/Meyer 2002). With short boiling at around 100 °C, though, it hardly plays a role.
When enzymes work — the reliable routes:
- Enzyme soak after boiling — soak finished, cooled boilies in an enzyme solution (details below)
- Enzyme liquids as a dip or coating — applied just before use
- Pre-digested protein solutions (hydrolysates) directly in the paste — the enzymatic process is already complete, the product is heat-stable and keeps its attraction even after boiling
- Targeted paste treatment before boiling — possible, but involved and more a job for bait companies: the enzymes work in the paste and are destroyed during boiling, while their breakdown products stay in the boilie
Pre-digested fishmeal – the best-known enzyme product
Hydrolysed fish protein is the most prominent and longest-known enzyme product in the fishing industry — even if it’s rarely called that. Fishmeal is treated with proteases at a controlled temperature and pH. The protein molecules are split into free amino acids and short peptides.
The result: almost 100% water-soluble, an instant attraction cloud on contact with water, easier to digest than whole fishmeal, a much more intense smell. And crucially: heat-stable — the enzyme product can go straight into the base mix without losing its effect through boiling.
When buying, always check the degree of hydrolysis (DH): a hydrolysate with a high degree of breakdown (degree of hydrolysis DH >30%) has more free amino acids and stronger attraction than one with a low degree of breakdown.
Key hydrolysate products for boilies:
- Fish hydrolysate — various fish species, broad amino acid profile
- Squid hydrolysate — squid broken down enzymatically, 95% pepsin digestibility, high proportion of water-soluble peptides. Squid + Scopex is regarded as one of the best-known boilie combinations of all
- Krill hydrolysate — intensely marine, rich in DMPT (dimethyl-β-propiothetin), a sulphur-containing attractant from marine algae that has been shown to trigger feeding reflexes in carp — with a stronger effect than glutamine (scientifically confirmed, Nakajima 1989)
- Liver hydrolysate — highly soluble beef liver, releases betaine immediately
- Casein hydrolysate — broken-down milk protein, creamy and slightly sweet, for light milk protein mixes
Process conditions – temperature and pH
Two factors matter for a correct enzyme soak:
Optimum temperature: the optimum temperatures differ: papain (from papaya) works best at 60–65°C, bromelain (from pineapple) at 50–60°C, starch splitters (alpha-amylase) at 55–70°C. For the enzyme soak: soaking boilies in an enzyme solution at 50–60°C is much more effective than soaking them cold — the water penetrates faster and both main enzyme classes work in their optimum range.
Optimum pH: neutral proteases work at pH 6–8 — matching most boilies (pH 7–8). Acidic enzymes (pepsin, pH 1.5–2) would be ineffective in a neutral boilie. For boilie applications, always choose neutral or slightly alkaline enzyme preparations.
Fermentation vs enzymatic breakdown — the big comparison
Fermentation and enzymatic breakdown produce the same end products — free amino acids, simple sugars, fatty acids. The process is fundamentally different:
That explains why fermented grains often smell more intense than enzymatically treated ones despite the slower process: the by-products (butyric acid, esters, alcohols) are themselves a strong attractant signal for carp — in practice, butyric acid is regarded as a particularly strong signal. Enzymatic breakdown is “cleaner”, but not automatically more effective.
Are enzymes the same as the bacteria in sourdough, yeast or salt fermentation?
No — but they’re closely related. The difference is fundamental and explains why the two processes deliver different results.
Enzymes are isolated protein molecules — no cells, no metabolism, no reproduction. They’re the tool. A protein splitter (protease) splits proteins into amino acids. Done. Nothing else.
Bacteria and yeasts are living organisms — they produce enzymes as part of their metabolism, and much more besides. When Lactobacillus bacteria break down particles in salt fermentation, all of this happens at the same time:
- Proteins → free amino acids (via the bacteria’s own proteases)
- Starch → sugar → lactic acid, acetic acid, butyric acid (via bacterial metabolism)
- Plus: esters, complex aroma molecules — a biochemically richer profile than isolated enzymes could ever produce
Butyric acid doesn’t come from enzyme treatment. It’s a by-product of bacterial metabolism. Isolated enzyme treatment alone doesn’t produce it — that’s one biochemical reason why fermented baits are often so effective.
The analogy: sourdough (Lactobacillus + wild yeasts) → a complex profile of lactic acid, acetic acid, CO₂ and hundreds of aroma compounds. Isolated amylase → only starch to sugar. No sourdough aroma, no complexity. In this sense, fermentation with brine or yeast is the natural enzyme soak — with the decisive advantage that living organisms keep producing new enzymes and adapt to the substrates.
The best strategy combines both: pre-digested protein solutions (hydrolysates) and an enzyme soak (fast, controlled, reliable) + fermented components (biochemically rich, butyric acid, complex attractants). Each approach covers what the other can’t.
Natural enzyme sources in everyday ingredients
Many boilie ingredients naturally contain active enzymes — without it saying so on the packaging:
- Fresh pineapple — contains bromelain (a protease). Fresh pineapple juice is active as a liquid. Industrially processed, heated pineapple juice no longer contains active bromelain
- Fresh papaya — contains papain (a protease). As a fresh extract or papaya powder made from raw fruit
- Raw, unheated honey — contains diastase (an amylase) and glucose oxidase. Heated honey no longer contains active enzymes
- Fermented CSL (corn steep liquor) — contains active enzymes from the fermentation process that break down residual starch further
- Fermented particles (hemp, tiger nuts) — contain active enzymes from the fermentation microorganisms after fermentation
Enzymes in practice – four application methods
Method 1 — enzyme soak after boiling (recommended)
- Boil the finished boilies and let them cool completely to room temperature
- Dissolve the enzyme liquid in warm water (50–60 °C)
- Soak the boilies for 12–48 hours
- Let them dry until the moisture level you want is reached
- Freeze them or use them straight away
The enzyme penetrates the boilie structure and keeps working until it’s frozen; in the freezer the activity largely rests and starts again after thawing. The best method for hookbaits.
Method 2 — pre-digested protein solutions (hydrolysates) directly in the paste
The safest and most reliable method. Ingredients that have already been broken down enzymatically keep their attraction even after boiling, because the enzymatic process is already complete. Add fish hydrolysate, squid hydrolysate, krill hydrolysate or liver hydrolysate directly to the base mix.
Method 3 — enzyme coating / enzyme dip
Concentrated enzyme liquid as a hookbait dip shortly before casting. Instant effect on the boilie surface. Limited depth of effect — ideal for short sessions without an established baited spot.
Method 4 — enzymes for particles
Soak maize, tiger nuts or hemp in an enzyme solution after cooking. Amylase breaks down remaining starch, protease breaks down protein. Result: particles with much stronger attraction, without the extra cost of expensive hydrolysates.
Special case — paste treatment before boiling
For anglers who roll their own, the enzyme soak after boiling is the standard. Treating the paste before boiling is possible but involved: the paste needs enough time at the right temperature for the enzymes to break down protein and starch – only then is it boiled. The enzymes themselves don’t survive boiling, but their breakdown products stay in the boilie and are released gradually in the water. This is more a job for bait companies – one example is Supreme Baits SupZym+ (see assessment below).
Which enzyme for what – overview
Preservatives and enzymes – an underestimated contradiction
This point is almost never discussed in the fishing industry — even though it directly affects how well many enzyme boilies work. Most shelf-life boilies are preserved. And the most commonly used preservatives can inhibit or destroy enzyme activity — including those from the food industry.
How preservatives attack enzymes
Potassium sorbate (E202) / sorbic acid — the most critical combination. Sorbic acid reacts with sulphur groups (thiol groups) in enzyme molecules. Particularly affected: protein splitters (proteases) that need a cysteine sulphur-group centre to function — these include papain and bromelain. This inhibition mechanism is well documented scientifically. An enzyme boilie preserved with potassium sorbate therefore loses a large part of its active cysteine proteases.
Sodium benzoate (E211) — inhibits a wide range of enzymes at the concentrations usual in boilies (0.1–0.3%). Not as specific as sorbate, but measurably effective as an enzyme inhibitor.
Propionates (E280/281) — less direct effect on enzymes, mainly antimicrobial. Less of a problem for isolated enzyme preparations.
Salt (NaCl) — in high concentrations, salt denatures proteins and so also reduces enzyme activity. In moderate amounts less problematic than chemical preservatives — but not a harmless enzyme soak partner either.
Tocopherols / vitamin E (E306–309) — no problem. Antioxidants, no antimicrobial effect on enzyme proteins. Enzyme-compatible.
When the contradiction matters — and when it doesn’t
The preservative–enzyme conflict is only relevant if enzymes are supposed to stay active in the finished boilie — i.e. with an enzyme soak or enzyme dip on shelf-life boilies. Potassium sorbate or benzoate in the finished boilie inactivate soaked-in enzymes at the surface.
For manufacturers who carry out the enzymatic breakdown in the raw paste before boiling, this point is irrelevant: the enzymes have already done their job in the paste, are destroyed during boiling, and the preservative-resistant breakdown products (free amino acids, sugars) stay in the boilie. After that, the preservation only protects the finished product — not active enzymes.
Practical recommendation: if you want to use an enzyme soak or enzyme dip, use freezer baits — no preservatives, no enzyme conflict. Shelf-life boilies with potassium sorbate or benzoate are biochemically unsuitable for subsequent enzyme treatment. Using tocopherol-preserved boilies is an acceptable compromise.
Critical assessment – what really works
Sound and proven: pre-digested protein solutions (hydrolysates) directly in the mix (heat-stable, reliable). Enzyme soak after boiling at the right temperature (50–60 °C) and pH. Full paste treatment before boiling (involved, more a job for bait companies) — the enzymes do their work in the raw paste and are destroyed during boiling, but their products (free amino acids, monosaccharides) stay heat-stable in the boilie. Supreme Baits SupZym+ takes this involved route: according to the manufacturer, the complete boilie paste is enzymatically prepared throughout the entire production process, and the bait type is protected as a registered utility model.
Questionable: enzymes that only go into the paste immediately before boiling — denatured without exposure time, practically useless. “Enzyme boilies” with no information on which enzymes were used and how they were processed. Claims of “activated” enzymes that survive boiling. So if you buy ready-made boilies, look for clear labelling – what else to look for when buying is covered in the guide to buying boilies.
The simple test: does an enzyme boilie smell more intense than a comparable normal boilie? Is the smell more complex, deeper — less like synthetic flavour, more like real food? Then a lot points to effective enzyme treatment – but the smell alone isn’t proof. No difference in smell is at least a warning sign.
Bottom line – two rules that decide everything
Enzymes aren’t a marketing gimmick — they’re real biochemistry that delivers real results when used correctly.
Rule 1 — active enzymes come after boiling. Always use an enzyme soak or enzyme dip after boiling and cooling – the standard for anglers who roll their own. If you put enzymes into the raw paste and boil straight away, you’re wasting money. A targeted paste treatment that runs long enough before boiling works – but it’s involved and more a job for bait companies.
Rule 2 — hydrolysates are the easiest solution. Pre-digested protein sources (fish hydrolysate, squid, krill, liver) reliably deliver the enzymatic attraction effect without any process risk — and can go straight into the base mix.
The best combination: hydrolysates directly in the mix + an enzyme soak after boiling for the hookbaits + natural enzyme sources (papain, bromelain, fermented CSL) as a boost.
→ All the background on ingredients, attractant systems and betaine in the complete boilie guide.
→ What really belongs in good feed boilies: feed boilies guide.
→ All boilie companies at Carp Austria at a glance.
Scientific sources
Arlinghaus, R. & Meyer, J. (2002) — „Wieso, Weshalb, Warum – Teil 3“. Scientific analysis of attractants, amino acids, betaine, flavour biochemistry and the attractant hierarchy in carp. Includes the assessment: enzymes, lecithin, oil/fat = no attractant effect.
Arlinghaus, R. & Meyer, J. (2001) — „Wieso, Weshalb, Warum – Teil 4“. Five factors for food intake in carp.
Nakajima, K. et al. (1989) — “A New Feeding Attractant, Dimethyl-β-propiothetin, for Freshwater Fish”. Nippon Suisan Gakkaishi 55(4): 689–695. Evidence of DMPT as a feeding trigger in carp with a stronger effect than glutamine.
Smith, L.H. & Hong-Shum, L. (2003) — Food Additives Data Book. Papain optimum temperature 65°C, pH range 5–8.
Carp Austria Editorial Team — Wolfgang G., master fish farmer (master craftsman qualification 2008) · carp angler for more than 40 years
