Glossary of food & beverage ingredient terms
P
| Term | Definition |
|---|---|
| Particle size |
Usually expressed as a particle size distribution giving the full range particle sizes found in the sample. Particle size of soluble products recovered from solution by drying e.g. maltodextrins, or by crystallization e.g. dextrose are determined by dry sieve methods. |
| Pasting temperature |
The temperature at which the viscosity curve produced in the Brabender viscograph leaves the baseline as the temperature rises during the initial heating process. |
| Peak viscosity |
The highest viscosity reached during gelatinization of starch usually corresponding to the point where all the granules are swollen to occupy a high proportion of the available volume with each in contact with its immediate neighbors. May be conveniently observed on the Brabender Viscograph. Note that on cooling the starch paste, the viscosity may rise above this level, but only the initial shoulder (Cornstarch) or true peak (Potato starch) values determined on the hot paste are termed peak viscosity. |
| pH |
The negative logarithm to the base 10 of the hydrogen ion concentration in solution. Universally used as a scale [from 0 to 14] as a measure of acidity [which increases from pH7 to pH0], and of alkalinity [which increases pH7 to pH 14]. pH7 represents the negative logarithm of the hydrogen ion concentration in pure water i.e. neutrality. |
| Physically-modified starch |
Starch which has been physically trated by the manufacturer without the introduction of new chemical groupings. Examples of physical modification include roll-drying, extrusion, spray drying, heat/moisture treatment etc. |
| Pituitous |
An undesirable textural attribute characterized by a long, stringy, snotty, discontinuous appearance usually caused by overcooked starch. An example would be uncooked egg whites. |
| Polydextrose |
a randomly branched anhydroglucose polymer made by heating glucose in the presence of acid and sorbitol. It is poorly digested because of its structure and, therefore, it has a caloric value of 1Kcal/gm compared to starch of 4Kcal/gm. It is used to replace nutritive sweeteners and sometimes fats in reduce calorie, low calorie, and sugar-free foods. |
| Potato starch |
Starch from potatoes. Potato starch granules are large, extending up to about 100 u in diameter. This starch has a low gelatinization temperature and is quite sensitive to alkalis. It is a highly swellable starch giving a pronounced viscosity peak. Potato starch pastes are more resistant to retrogradation than those of corn starch. |
| Powedered starch |
Commercial starch that has been milled and pre-sifted so that it passes through a sieve of specified size. |
| Pre-gelatinized starches |
these are instant starches that are precooked and dried by the starch manufacturer. A roll dryer is commonly used for cooking and drying. These starches are used, for example, in instant dry mixes. They exhibit a grainier texture than cold water swelling or granular instant starches in these products. |