[Fine Chemicals] Turning pale at the word 'additive'—how much do you know about additives in meat products?

[Fine Chemicals] Turning pale at the word 'additive'—how much do you know about additives in meat products?

Gelatin is a high polymer of high-molecular-weight polypeptides obtained by partially hydrolyzing collagen-rich tissues such as animal skin, bone, cartilage, ligaments, and muscle membranes. Gelatin looks white or pale yellow—translucent, slightly glossy thin sheets or powder granules—with a distinctive odor somewhat like meat broth. It spoils easily when damp because bacteria break it down quickly. Gelatin doesn't dissolve in cold water, but when you add water it slowly absorbs it, swells, and softens, taking up about 5 to 10 times its own weight. In hot water it dissolves fast into a viscous solution, and on cooling it sets into a solid gel. It doesn't dissolve in organic solvents like ethanol, ether, or chloroform, but it does dissolve in acetic acid and glycerol. You generally need about 5% gelatin in water to form a gel. The gel is soft, springy, and tender on the palate, and it melts and sets at around 25–30°C. The gel is thermally reversible—melts when heated, sets when cooled—and this property is often put to use in meat processing. For things like crystal pork trotter aspic or crystal pork stomach, gelatin is what gives you that high-clarity product. In meat processing, gelatin's roles come down to four things: nutrition, emulsification, binding and water retention, and stabilizing, thickening, and gelling.

5. Agar
   Agar is a polysaccharide, mainly polygalactoside. It comes as translucent white to pale yellow thin film strips, flakes, granules, or powder: odorless or with a faint peculiar odor; slippery and slightly slimy on the tongue; wrinkled surface, slightly glossy, light and soft but tough, hard to break—fully dried product is brittle; insoluble in cold water, but in cold water it can absorb 20 times its weight and swell and soften. It dissolves in boiling water; on cooling, a concentration below 0.1% gives a viscous liquid, 0.5% forms a firm gel, and 1% sets at 32–42°C, and that gel is elastic. When agar starts to gel, gel strength increases with time, but once fully set it shrinks from syneresis and strength drops. Agar gels are firm and give a product some shape, but the texture is coarse and brittle and the surface tends to shrink and wrinkle. Although agar is fairly heat-resistant, heating too long or strongly acidic conditions will destroy its gelling ability.

6. Carrageenan
   Carrageenan is the calcium, potassium, sodium, and ammonium salts of polysaccharide sulfates made of galactose and anhydrogalactose. It's a white or light brown granule or powder, odorless or faintly odorous, tasteless or with a slight seaweed taste. It dissolves in 80°C water; if you first wet it with ethanol, glycerol, or saturated sucrose water, it disperses easily in water. Boil carrageenan with 30 times its weight of water for 10 minutes and cool it, and it forms a gel; it reacts with protein to emulsify, and the emulsion is stable. Dry carrageenan is stable and doesn't degrade on long storage; it's stable in neutral and alkaline solutions, with an optimum pH of 9.0, where it won't hydrolyze even when heated. Its gel strength is lower than agar's, but it's more transparent.

Carrageenan is used as a thickener, emulsifier, blending agent, gelling agent, and stabilizer. The hygiene standard for food additive use says carrageenan may be used in various foods in amounts according to production needs.

It can be combined with many other gums. For example, adding xanthan gum makes carrageenan gels softer, more viscous, and more elastic; interacting with konjac gum forms an elastic thermally reversible gel. In meat processing, adding carrageenan gives products a fat-like mouthfeel, so it can be used to make premium low-fat meat products.