Observing the staling of white pan bread using the TVT texture analyzer

Jennifer M.C. Dang and Bronwyn Elliott
Perten Instruments of Australia

The most common objective method for bread texture assessment is the single compression test, where the sample is subjected to a low compressing force, which mimics the subjective measurement of crumb texture made by the fingers during squeezing (Cauvain, 2009). The TVT performs fast, easy to use, objective texture analysis of ingredients, in-process and finished foods and other products. Force, distance and time measurements were analyzed to define physical properties of the products in question. In this study the TVT was used to observe the staling of white pan bread using AACCI Standard Method 74-09.01 (AACCI, 1999).

Texture analysis was performed, in triplicate, at days 1, 3, and 7 after baking, according to test settings as shown in Table 1. During the test, the probe compressed the sample to a pre-defined percentage (40%) of the sample height, and the compression force recorded. The low compression force is insufficient to rupture the crumb matrix, and the product will generally return to its uncompressed form on removal of the compressing force (Cauvain, 2009). In this method, the firmness, a measure of freshness and quality, is taken as the Compression Force Value (CFV), which is the force required to compress the sample by 25% (distance of 6.25 mm). The firmness is a measure of freshness and quality.

Figure 1 shows the force-time curve of the commercial white bread throughout testing. The firmness of the bread increased upon storage, consistent with the effects of staling (retrogradation of amylopectin).

 

 

 

 

 

 

 

 

Table 1. TVT test mode settings.
Test mode name: 01-01.02 Bread Crumb Firmness, AACCI (74-09.01)
Sample thickness: 2.5 cm slice (or 2 x 1.25 cm slices) 

 

 

 

 

 










Figure 1
. Force-time curves of commercial white bread at one (white), three (yellow) and seven (red) days after baking.

References

  1. AACC International. Approved Methods of Analysis, 11th Ed. Method 74-09.01. Approved November 8, 1995, Reapproved November 3, 1999. AACCI, St. Paul, MN, doi: 10.1094/AACCIntMethod-74-09.01
  2. Cauvain, S.P. 2009. The relevance of testing to the manufacture of bread and fermented products. In: Ceeals, Flour, Dough and Product Testing – The ICC Handbook of Methods and Applications, eds S.P. Cauvain and L. Young, pp. 125–155, Lancaster PA, ICC, DEStech Publications, Inc.