The study ‘Effect of freezing treatments and yeast amount on sensory and physical properties of sweet bakery products’ experimented formulating Kougelhopf with different freezing temperatures and yeast quantities to achieve results comparable to a fresh product.
The authors, Smail Mezianiet al.,said that products made with unfermented frozen dough presented a better prospect for the industry compared to partly-baked and fully-baked products, but were associated with volume decreases and a poorer final product.
The study said: “Increasing yeast in frozen sweet doughs improved the overall quality of Kougelhopf compensating for the loss of yeast activity during the freezing process.”
“Kougelhopf produced from sweet dough with higher yeast content (DY) presented a higher specific volume, whereas freezing rate increases its hardness,” it said.
To reach its findings, the researchers used two types of sweet dough simple yeasted (SY) and double yeasted to produce Kougelhopf.
They froze the sweet doughs at different temperatures (-20°C, -30°C and -40°C) and conducted a physical assessment and sensory evaluation of the final product, where taste and appearance was assessed by 140 people.
These Kougelhopfs were compared to the control sample, a fresh Kougelhopf.
The researchers found that single yeasted dough Kougelhopfs exhibited lower volumes compared to fresh ones.
However, Kougelhopfs with double yeasted dough showed comparable volumes to fresh products and did not result in a yeast aftertaste.
Double yeasted dough frozen at -30°C and -40°C were found to give the best results.
The research was published in the Journal of Food Engineering and funded by French bakery firm Coco LM Company.
Study: Meziani, S., et al. Effect of freezing treatments and yeast amount on sensory and physical properties of sweet bakery products. Journal of Food Engineering (2012), doi:10.1016/j.jfoodeng.2012.02.015