Soft and hard wheat samples were tempered using ozonated water (1.5 and 11.5 mg ozone/l). Milling (rate of extraction), rheological (farinograph and extensograph characteristics)., chemical (protein, falling number, sedimentation volume), colour (Hunter Lab values and microbiological (total bacterial and yeast/moulds) properties of the parent flours were evaluated. Results indicated that tempering with ozonated water did not significantly alter the chemical, physical and rheological properties of the flours, A statistically significant reduction in the total bacterial and yeast/mould counts were obtained after tempering with ozonated water (p<0.05). Results suggest that the water ozonated up to 11.5 mg/ ozone/l can be successfully used in the tempering of soft and hard wheat without deterioration in the flour quality.
Ozone is a powerful antimicrobial intervention commonly used in food processing and storage applications. There is a desire to bring the benefits of ozone to the flour milling industry, this research was performed to evaluate the potential negative or positive effect of ozone on the properties of the wheat, and finished flour product. This research also evaluated the effectiveness of ozone as an antimicrobial intervention on the finished flour product, this was evaluated by testing the total bacteria count, and Mold/yeast count in the finished flour.
Two different wheat varieties were used for this testing: Adiyaman Beyaz (a soft white wheat) and Arjantin (a hard red wheat). These varieties were selected to represent a strong and weak wheat commonly used in flour for bread making. Soft wheat was tempered to a moisture content of 15.5%, while hard wheat was tempered to a moisture content of 16.5%. Full analysis of the flour was performed on three separate samples of each type of wheat, these were as follows:
- Wheat was tempered with water
- Wheat was tempered with 1.5 mg/l dissolved ozone
- Wheat was tempered with 11.5 mg/l dissolved ozone
Microbiological analysis was also performed on untempered wheat ground into flour
Results show that the ozone treatment did not alter the milling efficiency of either the soft or hard wheat. The physical, chemical, rheological, and color of the finished flour was also not affected by either the ozone treatment of either the hard or soft wheat flour samples.
Total bacteria along with mold and yeast counts were statistically lower in the ozone treated samples of both the hard and soft wheat flour samples. These results can be seen the table below.
This research does suggest that ozone can be implemented into the tempering process as an effective antimicrobial intervention step without negatively affecting the finished flour product.
Influence of tempering with ozonated water on the selected properties of wheat flour
Department of Food Engineering, Faculty of Engineering, The University of Gaiziantep, 27310 Gaintep, Turkey
Accepted 14 October, 2000
Author: Senol Ibanoglu