Image	Information/Resources
	These are a number of many temperature measuring devices. Since so much of food quality is influenced by temperature it is important to select one of these devices to quantitate the history.
	The thermocouple is essentially two different metals joined at one end and hooked up to some voltage detector at the other. This particular thermocouple is made of copper and constantan. It is hooked to a temperature recorder which converts the voltage into temperature.
	There are a number of different type of thermometers. This is a griddle thermometer.
	This is the linesource set-up which allowed the gathering of data to calculate the thermal conductivity and thermal diffusivity. Essentially, it consists of a wire of known resistance and length where one can send a voltage down. This voltage will cause a temperature change in the sample around the wire. Also, within a set distance there is a thermocouple to measure the temperature change. Through the fantastic process of computerization and the expertise of mechanical engineering, thermal properties can be calculated from this data.
	The pycnometer is a little known device to measure specific gravity of foam products. The advantage is that one can put the sample into the small container, screw on the lid, wipe off the extra sample that comes out the top and weigh the totality. This can be compared to the previous weight of water.
	Specific gravity of fruits and vegetables, such as potatoes, can be determined by using solutions of various salt concentrations.
	Measuring of distance can be done with vernier calipers.
	Certainly, a ruler is an effective crude method of evaluating length, width or other distance parameters.
	This visopan allows for projection on a screen of microscopic slides/materials/and such.
	History, quality control and experimental control can be assisted with by the weighing of ingredients. In this particular picture, the cake batter is being weighed as it is placed in the pan.

Brady, P.L. and S.M. Mayer. 1985. Correlations of sensory and instrumental measures of bread texture. Cereal Chemistry : 70.

Table 1. Sensory and Instrumental Description for Each Textural Characteristic

Textural Parameter	Sensory Definitiona, b	Instrumental Definition
Hardness	Force required to compress between the molar teeth. 1=soft; 14=hard	Height of curve 1 (kg)
Cohesiveness	Force necessary to break apart; degree of compression by molar teeth before breaking. 1=compresses a lot before rupture; 14=ruptures easily	area under Curve 2 over area under Curve 1
Elasticity	The degree and quickness of recovery after compressing force of molar teeth is removed. 1=stays compressed; 14=quickly returns to size and shape	Width of Curve 2 from start of rise to point of maximum height (i.e during downstroke [mm])
Chewiness	Amount of time (in seconds) required to chew until ready to swallow. 1=not chewy; 14=chewy. Number of chews to prepare sample for swallowing.	Hardness x cohesiveness x elasticity

aFrom Szzesniak (1963)
bA separate bread disc was used for each parameter.
cUsing an Instron TPA curve (Bourne 1978).

Updated: Wednesday, December 5, 2007.