Texture Evaluation of Yeast Blocks

Application

A processor of yeast blocks was looking for a quantifiable, consistent way to measure and ultimately better control the texture of their product. Current methods involved simple visual inspections and very subjective human sensory evaluation.

Problem

Yeast blocks are extremely susceptible to either drying out too quickly or retaining moisture and becoming clay-like if not handled and packaged in the proper manner. In addition, the company runs different formulations and therefore the texture will vary between formulations. Because of these factors, a consistent and repeatable method of measuring and therefore controlling the texture is essential.

Solution

Before testing, samples were left in their wrapping to hold the sample together for testing. All testing was done using a TMS-Pro with a 4mm cylinder probe which ran at a speed of 50 mm/min and 15mm into the block. The graph to the right shows the probe entering the product (1st curve) and the probe exiting the product (curve under line). This negative force tells us how the product fractures, if at all, when probe is exiting. This indicates whether the product is dry and crumbly or moist and sticky.

Conclusion

Test method and system proved differences between blocks of different formulations Allows for more concise control of textural attributes of the product Reduces the possibility of downtime due to a product that does not meet quality standard.