The primary difference in risk between these proteins lies in the physiological structure of the animal and the typical environments where their pathogens reside.

In poultry, pathogens like Salmonella and Campylobacter often colonize the intestinal tracts and skin of the birds. During industrial slaughter and feather-removal, it's common for these bacteria to be spread across the entire surface and into the muscle tissue. Because poultry muscle is relatively porous compared to bovine muscle, bacteria can migrate more deeply into the meat.

Beef, on the other hand, is significantly more dense than poultry. In intact cuts of beef, like a steak, pathogenic bacteria like E. coli are usually only on the exterior surface. Searing the outside of a steak to 145°F (63°C) effectively kills these surface pathogens, which is why the interior can safely remain rare. However, once beef is ground, those surface bacteria are mixed throughout the meat, necessitating an internal cooking temperature of 160°F (71°C). The same is true if the meat is punctured (such as with a Jaccard) — it will need to be cooked to 160°F since the bacteria are pushed inside the meat.

While fish certainly carry risks, they differ in type and magnitude. Salmonella is occasionally found in fish (usually due to contaminated water or poor handling), but it is far less common than in land-based poultry. The primary concerns with raw fish are parasites (like anisakid nematodes) and histamine poisoning. Tuna is uniquely less susceptible to many common parasites because it is a highly migratory, pelagic (open-ocean) fish. Most parasites require an intermediate host found in shallower, coastal waters. Because tuna spend much of their lives in the deep, open sea, their exposure to these specific life cycles is greatly reduced. "Sushi-grade" fish is typically frozen to temperatures as low as —31°F (—35°C), which is a kill step designed to destroy any parasites before consumption. This is not required in the U.S. for tuna or for some farmed fish.

Ceviche "cooks" fish through a process called acid denaturation. The citric acid from lime or lemon juice lowers the pH, causing the proteins to unwind and coagulate, which mimics the texture of heat-cooked fish. While this can reduce some bacterial load, it is not a reliable kill step for all pathogens or parasites, which is why using high-quality, previously frozen fish is essential. We don't eat raw poultry because of the high prevalence of Salmonella and E. Coli in grocery store chicken, and because of the permeable nature of the meat, which makes the risk-to-reward ratio far too high compared to the relatively lower and more manageable risks associated with beef and deep-sea fish.

Chef Michael

Breaking down cellulose specifically to release glucose for the Maillard reaction is a challenge of chemical kinetics. While starch is a polymer of α-glucose that enzymes and heat can readily dismantle, cellulose is composed of β-glucose monomers linked by β-1,4-glycosidic bonds. These chains are reinforced by extensive hydrogen bonding, creating crystalline microfibrils that are incredibly resistant to thermal and chemical degradation.

To understand why breaking down cellulose is so difficult, you have to look at the geometry of the bonds you are trying to break. The α-bonds in starch create a coiled, helical structure that is easily accessible to water and enzymes. But the β-bonds in cellulose create a flat, linear ribbon, which get very close to one another and form strong hydrogen bonds, as you point out in your question. These stacked molecules make it extremely difficult for water to penetrate.

To maximize the speed of cellulose breakdown and subsequent browning, you could take any of these approaches:

1. Alkaline Environment (shifting the pH upward). This is the most effective way to accelerate the breakdown of hemicellulose and weaken the cellulose matrix. Pectin, which acts as the "intercellular glue," dissolves rapidly in alkaline conditions. To do this, add a small amount of sodium bicarbonate (baking soda) to the cooking water or directly onto the vegetables. The alkaline environment catalyzes the " β-elimination" reaction in the pectin and starts to loosen the cellulose fibers. This also lowers the activation energy required for the Maillard reaction, allowing browning to begin at lower temperatures and much faster than it would at a neutral or acidic pH. Obviously if you start in water you'll need to dry and roast or use some other high-heat cooking process to allow Maillard browning to occur at any reasonable pace. 

2. High-Pressure Steam. Cellulose has a high thermal stability, meaning boiling at the normal temp of 212°F (100°C) is relatively inefficient at breaking those β-bonds. Instead, use a pressure cooker. By increasing the pressure, you can raise the boiling point of water to around 250°F (121°C). This extra thermal energy significantly increases the rate of hydrolysis. When combined with the baking soda method mentioned above, you can turn fibrous vegetables into a browned puree in a fraction of the usual time. Here, it's even possible to brown without getting rid of the water. You might want to try this recipe: https://modernistcuisine.com/recipes/caramelized-carrot-soup-no-centrifuge-necessary/

3. Exogenous Cellulase Enzymes. If you want to be precise about releasing glucose without relying solely on blunt-force heat, you can use biotechnology. Treat the vegetable mash with a food-grade cellulase enzyme (often derived from Trichoderma reesei) before cooking. These enzymes specifically target and cleave the β-1,4-glycosidic bonds, converting the insoluble fiber directly into fermentable and "Maillard-ready" sugars. You would hold the vegetables at the enzyme's optimal temperature — usually around 120 – 140°F (49 – 60°C) — for thirty to sixty minutes before proceeding to high-heat cooking.