# Application PNR 12: Consistency of Margarine and Other Edible Fats

## The Penetrometer PNR 12 is suitable for consistency measurements required in the food industry. Various accessories and test kits according to the AOCS and the Unilever method are available for edible fats like butter, margarine and others.

### PNR 12 – Test Principle

The PNR 12 is a gravity penetrometer and measures the resistance a material provides against being pierced by a specifically shaped test body. A needle-shaped or conical test body is lowered precisely to the sample surface, and then sinks into the material by its own weight during a defined period of time. This penetration, which is indicated in penetration units (PU) or directly in millimeters, allows a rating of the plasticity or consistency.

Due to its easy handling and convertibility the penetrometer PNR 12 has gained a wide scope of application. It is an ideal solution for consistency tests of butter, margarine and other edible fats.
Common procedures of testing these products are the AOCS method Cc16-60 or the Unilever method. These methods use test cones with different angles.

Fig. 1: Penetrometer PNR 12 without accessories

Fig. 2: Test Kit "AOCS" (106946)

Fig. 3: Test Kit "Unilever" (106922)

The penetration depth in tenth of millimeters is reported and used to calculate the C-value (yield point or consistency value of margarine) in g/cm2.
The PNR 12 will display the C-value directly after the measurement is finished.

### C-Value Calculation

C = K • W / Pn

Where:
C = yield point value
K = factor cone angle dependent (20° factor 19000 or 40° factor 5840)
W = weight of cone and plunger in g
P = penetration in 0.1 mm
n = 1.6 for margarine, baking fat and butter

### Examples for Yield Point Values

C-Value
< 100 200 to 800 > 1500
very soft,
not shape retaining
best consistency,
too hard,

### Test Kits Available According:

AOCS method (106946)
Consisting of:
1 aluminum cone 20°, 45 g
1 plunger, 47.5 g

Unilever method (106922)
Consisting of:
1 aluminum cone 40°, 31.5 g
1 plunger, 48.5 g