Gelatin is made from collagen, the main structural protein found in animal skin, bones, and connective tissue. Manufacturers extract it primarily from pig skin and cattle hides, then process it into the odorless, translucent powder used in everything from gummy bears to medicine capsules. The largest single source of commercial gelatin is pork skin, followed by cowhide and cattle bones.
Which Animals and Parts Are Used
The animals used for gelatin are the same ones raised for meat. Pig skin is the most common raw material worldwide, while bovine sources (skin and bone) accounted for the largest market revenue share at about 35% in 2024. Poultry and fish make up smaller but growing segments of the market.
The specific parts used are the ones left over after meat processing. For pigs and cattle, that means hides, split skins, and bones. For poultry, it’s primarily skin and feet. For fish, the skin, bones, scales, and swim bladders all contain usable collagen. Fish skin alone makes up about 8 to 10% of a fish’s total body weight, and roughly 40% of a fish’s total catch weight ends up as byproducts that can be processed this way.
None of these raw materials would otherwise end up on your plate. Gelatin production is essentially a way of converting slaughterhouse and processing byproducts into a useful ingredient.
How Collagen Becomes Gelatin
Collagen in its natural state is tough and insoluble. It’s what makes tendons strong and skin elastic. Turning it into gelatin requires breaking down that rigid structure, and the process happens in stages.
First, the raw materials are cleaned and pretreated with either an acid or an alkaline solution. This step softens the tissue and begins loosening the tightly wound collagen fibers. Acid-treated material produces what’s called Type A gelatin, while alkaline-treated material produces Type B. Pig skin is typically acid-processed, and cattle hides are typically alkaline-processed. The pretreatment stage can take anywhere from a day (for acid) to several weeks (for alkaline).
Next comes the extraction itself: the pretreated material is heated in water at temperatures between 40 and 80°C (roughly 105 to 175°F). Heat unwinds the collagen’s triple-helix structure, converting it into soluble gelatin that dissolves into the water. The resulting liquid is filtered, concentrated, and then dried into sheets, granules, or powder. Drying typically happens in hot air ovens at around 45°C or through freeze-drying at extremely cold temperatures near negative 50 to 60°C.
What Gelatin Actually Contains
Gelatin is almost entirely protein, roughly 85 to 90% by weight, with the rest being water and trace minerals. Its amino acid profile is distinctive and quite different from other protein sources. About a quarter of gelatin’s amino acids are glycine (25.5%), followed by proline (18%) and hydroxyproline (14.1%). That last one, hydroxyproline, is almost exclusive to collagen-derived proteins and is part of what gives gelatin its unique gelling ability.
What gelatin lacks is also notable. It contains almost no cysteine (0.1%) and is missing tryptophan entirely, which means it’s not a complete protein. You couldn’t rely on it as your sole protein source, but that’s not really how anyone uses it.
How Gelatin Quality Is Graded
If you’ve ever compared gelatin products and noticed different “bloom” numbers on the packaging, that’s a standardized measure of gel firmness. Bloom strength is tested by measuring how much force (in grams) it takes to push a small probe 4 millimeters into a set gelatin sample. Higher bloom numbers mean firmer, stronger gels. Professional-grade gelatins range from about 50 bloom (very soft) to 300 bloom (very firm). Most consumer gelatin falls somewhere in the middle.
This matters practically because higher-bloom gelatin sets faster, produces a firmer texture, and requires less product to achieve the same result. Lower-bloom gelatin creates softer, more delicate gels.
Gelatin in Medicine and Supplements
Pharmaceutical companies prefer mammalian gelatin over fish or poultry sources because it produces more stable capsule shells. Hard gelatin capsules need 12 to 16% moisture to maintain their structure, and the gelatin works best between pH 4 and 7. Soft gel capsules use the same base material with added plasticizers to keep them flexible.
Safety-wise, the FDA classifies gelatin as “generally recognized as safe” (GRAS). One concern specific to bovine gelatin is the theoretical risk of transmissible spongiform encephalopathy, the family of diseases that includes mad cow disease. For this reason, gelatin processors avoid using skull and spinal column material from cattle, and alkaline processing further reduces any potential risk. Skin-derived gelatin carries less risk than bone-derived gelatin overall.
Fish Gelatin as an Alternative
Fish gelatin has become increasingly important for communities that avoid pork or beef products for religious or dietary reasons. Fish skin collagen dissolves more easily in acid than mammalian collagen, and the resulting gelatin is typically Type A. It works well in many of the same applications, though fish gelatin generally sets at lower temperatures and produces softer gels than pork or beef gelatin.
Because fish skin is already a major byproduct of the filleting industry, it’s a practical and readily available source. It also sidesteps concerns about mad cow disease entirely.
Plant-Based Substitutes
No plant produces actual gelatin, since collagen is exclusively an animal protein. But several plant-derived ingredients can mimic gelatin’s gelling behavior in recipes and food manufacturing.
- Agar is derived from red seaweed and sets firmer than gelatin. It’s the most common direct substitute in cooking and is widely used in Asian cuisines.
- Pectin is a carbohydrate found in plant cell walls, commercially extracted mainly from apple pomace and orange peel. It’s what makes jams and jellies set.
- Carrageenan also comes from seaweed and is used in dairy products, desserts, and plant-based meat alternatives to create gel-like textures.
- Konjac is a root vegetable used in Japanese cooking that produces a firm, resilient gel. It’s the base ingredient in shirataki noodles.
These substitutes don’t behave identically to gelatin. Each has a different melting point, texture, and setting behavior, so swapping one for another in a recipe often requires adjusting ratios and expectations. Agar, for instance, doesn’t melt in your mouth the way gelatin does, because it stays solid at much higher temperatures.