1. Density
Usually the density of the material is calculated based on the ratio between the weight and volume of materials (weight-volume ratio). There are three kinds, namely density, relative density (relative density), absolute density (absolute density), and the apparent density (apparent density). Absolute density is defined as the volume of mass unity. Mass is multiplied by the weight of gravity. Therefore the earth’s gravity affect the absolute density.
Relative density is a relationship between the density of the material at a certain temperature compared with standard density (usually water) at the same temperature. Real density (apparent density) is defined as the volume of material (apparent displacement) divided by the weight of the material. In this case, a container of known volume is filled with a number of ingredients that have been known to weigh. Divided by the weight of the container volume is a real density of the material.
2. Length, width and diameter
Measurement, length, width and diameter of a material is usually intended to determine the uniformity of the material. Rapid measurement usually use a colander or sieve which is based on the size of the filter holes of the sieve with holes of the above come to the small hole in the bottom. Hole shape adapted to form a desirable material for example circular, square and triangle. A kind of sieve apparatus used in the sorting of materials. Measurement of the length, width and diameter can also be done using tools such as rulers and micrometers. Micrometer accuracy is much higher than the crossbar.
3. The color and luster
Color is a material nature to be attributed to the spread spectrum, as well as gloss properties of the material is influenced by light primarily reflected ray. Beam that can be seen someone limited by the wave, ie from 380-770 nm (nanometers). Outside of these wavelengths, practical eye can not feel it.
If you look further, the color is not a substance or object but only a sensation of a person due to the stimulation of the energy beam of radiation that falls onto the retina of the eye. The emergence of color is limited by the most important factor is the presence of a light source. Influence is seen when a material or object seen in a dreary place and in a dark place, will provide striking color differences. This experience is usually used by traders to manipulate cloth products traded with the use of colorful lights.
4. Viscosity and consistency
Viscosity and consistency is an important trait, especially for foodstuffs such as juice, sweets, oil, syrup and so on. Viscosity and consistency are very closely related to the sense of touch and sight. This quality factor is not only measured to demonstrate the consistency of the final results processed, but also raw materials or changes of each stage of processing for estimating the final consistency.
Viscosity is useful as a measurement criterion for change material (disagregation) or depolymerization such as might occur due to hydrolysis of proteins, starch and pectin. The quality factor is also important in the determination of molecular weight. To conduct measurements of viscosity and consistency of materials used instrument called “viscosimeter” and “consistometer”.
5. Texture or kinesthetics
Nature “kinesthetics” closely related to the sense of touch, these properties are also often called the “sensory characteristics” that belong to the nature of which is determined by the sense of touch (finger feel) is firmness (firmness) and tenderness (softness) that can be measured by way of emphasis (compression), and the “juiciness” tested to be massaged by the thumb for example, testing the maturity of corn. In addition to the physical factors that have been discussed above, there are many physical factors that typically applies unique to each type of material associated with the purposes, the use of such materials.
Physical factors in question include the refractive index and optical rotation that is often used as a determinant of the quality of essential oils; elasticity, tensile strength that is often used as a determinant of the quality of rubber and other polim; receive strength and power of divisive pressures are often used as a determinant of the quality of hard board (hardboard) for building materials.
Table 1. Grouping / grading of the mangosteen fruit
