The research, published in the journal Food Hydrocolloids, may offer formulators an interesting avenue of exploration to improve the stability of tapioca-based emulsions, an area of growing interest highlighted recently when Cargill acquired Thai-based Chai Charoen Tapioca Flour Factory Company that specialises in developing and producing native tapioca starches primarily for the food industry.
"The results [of this study] indicate that the best treatment conditions for the reduction of starch retrogradation was the addition of 0.50 per cent xanthan gum with a freezing rate of 2.30 degrees Celsius per min," wrote authors Janya Muadklay and Sanguansri Charoenrein from Kasetsart University, Bangkok.
"Furthermore, it could retard changing of texture in tapioca starch gel to a spongy structure during repeated freeze-thawing," they added.
The researchers tested the effectiveness of four commercial hydrocolloids - xanthan gum, locust bean gum and guar gum (donated by Berli Jucker Public Company), and konjac-glucomannan (DKSH Company) - for stabilising tapioca starch gels.
The chemical structure of the hydrocolloid was found to determine their ability to stabilise tapioca, with xanthan gum the most effective in reducing the formation of curd (syneresis), while the locust bean gum and konjac-glucomannan bothe performed better than guar gum.
"It is assumed that molecules of guar gum were not suitable for interaction with amylose molecules of tapioca starch in this study or it might have occurred from an excessive concentration of guar gum," wrote the researchers.
Xanthan gum is said to be one of the only exceptions in avoiding the price rises being experienced by many hydrocolloids. Rising energy, raw material and transportation costs have seen the cost of nearly all hydrocolloids increase in the last year according to hydrocolloid information service IMR's Quarterly Review.
Source: Food Hydrocolloids (Elsevier)
Published on-line ahead of print, doi: 10.1016/j.foodhyd.2007.06.008
"Effects of hydrocolloids and freezing rates on freeze-thaw stability of tapioca starch gels"
Authors: J. Muadklay, S. Charoenrein