Brookfield AMETEK

Peanut Butter

Peanut Butter (creamy style)

Laboratory Viscometer Application Data Sheet

APPLICATION

Creamy Peanut Butter is typically spread onto other foods, such as breads, in making peanut butter and jelly sandwiches, for example, or incorporated into various food products.

Test Equipment

  • Spring Torque Range: Various, such as HB
  • Spindle: Various T-bars, such as T-C
  • Accessory: Helipath Stand
  • Speed, rpm: Various, such as 5 rpm

The products were tested in their jars at room temperature.

The Helipath Stand may be used with various Brookfield Viscometers or Rheometers. The choice of Spring Torque Range, spindle and speed may vary widely, depending upon the creamy peanut butter. In our example, we used a Brookfield HBDV-II+PRO, with Rheocalc v3.1 software for automated instrument control and data acquisition. Representative data from the analyses are shown in Figure 1, below:


Figure 1: Creamy Style Peanut Butters at room temperature.

Brand B, shown in light brown, is significantly more viscous than Brand A, shown in dark brown. The Helipath data traces progress from "zero" viscosity - before the spindle drills down into the material - to a "plateau" region where the spindle is in the bulk of the sample. The system then reverses direction, and the measured torque - and calculated viscosity - then drops to "zero" as the spindle rises up and out of the sample. The "plateau" for both product data is between approximately 50 and 400 seconds. The decrease in viscosity, at about 225 seconds, occurs as the system first reverses direction. The spindle now travels through material whose structure may have been partially disrupted by the initial portion of the test. Therefore, the "plateau" viscosity from 250 to 400 seconds is somewhat lower than the "plateau" from 50 to 200 seconds. Some users, therefore, prefer to use data from only the first "plateau".

The Rheocalc data may be exported to a spreadsheet, and the plateau-region data averaged, to give a QC/QA number for viscosity. On the other hand, the Data Averaging feature available in the Rheocalc Wizard may also be used to output averaged data values. Another choice may be to simply have the system "drill" down into the sample for a specified amount of time, say 100 or 120 seconds, and then have the operator record the viscosity value at that time. This last procedure provides a one-point test.