Chemistry 102 | Exam III | Chapter 18

Spoilage has two primary causes: microbial action (bacteria or molds) and the action of enzymes which are normal components of the produce or meat itself.

Freezing does more than simply lower the temperature further than refrigeration. Below 0 C, the water molecules undergo a phase change from the liquid phase to the solid phase; in the solid crystal lattice the water molecules are much less available to participate in chemical reactions, and hence the biochemical reactions of spoilage which take place in aqueous solution are slowed drastically.

Adding lots of salt or sugar to a food kills bacteria and molds or slows down their growth drastically by drying up their cells. Osmosis is the movement of solvent molecules through a partially permeable membrane into a higher solute concentration, in order to equalize concentrations on the two sides.

When bacteria find themselves in a highly concentrated solution of salt (curing) or sugar (preserving), water migrates out through the membranes of their cell walls to make the surrounding solution more dilute and the concentration of dissolved substances inside the cells more concentrated in a kind of "balancing act." If the surrounding solution contains high enough concentrations of dissolved material, the bacterial cells in the food become too dried out from this process to be able to function, and the bacteria may die.

Sugar, usually sucrose.

Sodium Chloride, Potassium Chloride, Potassium Nitrate,

KNO3, NaCl, KCl,

No, the functional group (benzoate) is still the same.

Nitrites not only preserve and flavor meat, but give it an attractive bright pink color.

In 1956 it was shown that nitrite ion can combine with the amine functional group on amino acids or other organic compounds found in the body to form compounds called nitrosamines, which are known to cause cancer in animals. The concern is that cancer-causing nitrosamines can be formed by the reaction between nitrite and amines in acid conditions like those of the human stomach.

Salted meats like ham, bacon, and hot dogs are a dietary source of nitrite.

The 3, very hydrogen bondable with water, “hydroxyl” groups OH

This is because of its long chained hydrocarbon region and the fact that only one OH group is presents to hydrogen bond with and dissolve almost 30 carbon atoms. It’s very non polar

l this is Vitamin E, a natural vitamin in our body and some plants

The oxidation reactions which cause fats to become rancid takes place most readily in unsaturated fats, because the carbon atoms next to carbon-carbon double bonds react with oxygen, making organic compounds called hydroperoxides. Hydroperoxides react further, breaking apart to form aldehydes, ketones, and lower-molecular-weight acids, typically odorous compounds that produce the smells of rancid fat. Polyunsaturated fats, those with more than one double bond, are especially prone to this type of oxidation, because they can have a carbon atom located between two double bonds, with both double bonds acting to enhance the formation of hydroperoxides at that site. Hence saturated fats with no double bonds are much less prone to rancidity because of the lack of formation of hydroperoxides.

Yes, by supplying it with the following chemical recipes for taste and odor respectively.

Solvent

Coloring agent

flavoring agents.

Artificial sweetener

Preservatives

Stimulant

The candy is transmitting yellow wavelengths of visible light and hence is subtracting or absorbing its complementary color blue at wavelengths 435-480 nm.

We see the colors that are not absorbed by the dye molecule bonds i.e. Yellow