Writing in the Journal of Dairy Science, researchers at South Dakota State University in the US suggested that just a small change in storage temperature could help put the freeze on energy costs.
Currently the industry standard for storing ice cream is – 28.9oC. The International Dairy Foods Association states that any ice cream stored at the manufacturer or during shipping and distribution above that temperature should not be sold at retail.
Analysing impact on ice cream quality
But the new study indicates that this limit is too conservative. The authors said manufacturers could easily increase the temperature of their freezers to – 26.1oC without putting product quality at risk.
They came to this conclusion by analysing both full fat and low fat vanilla ice cream kept at different temperatures for up to 39 weeks.
The ice crystals in ice cream were measured. This is because higher temperatures can cause crystals to expand, giving an undesirable icy texture. And a sensory panel was drafted in to judge the body/texture and flavour.
The authors of the study found no significant differences in the quality of ice cream stored at different temperatures – even at the highest level of - 23.3oC. Changes in ice crystal size over time were no different at the different temperatures and the sensory panel did not find any variation either.
Freezer temperature recommendations
The scientists concluded that freezer temperatures could be increased 2.8oC to -26.02oC but preferred not to recommend any further increase although the results indicated that storage at - 23.3oC would not affect product quality.
Study author Professor Robert J. Baer told DairyReporter.com: “Freezers typically fluctuate several degrees from their set point. Thus, even though the -23.3 C temperature did not affect ice cream quality, we did not feel comfortable in recommending that temperature, due to possible fluctuations in temperature.”
Baer added that even a small temperature increase of 2.8oC could make a significant difference to energy bills, although the research team did not evaluate the impact.
He said: “By increasing the temperature it would for sure lower energy costs. Just guessing, I would think it would be several percentage points in energy savings (which would be significant, particularly with energy costs going through the roof).”
Source: Journal of Dairy Science
Vol. 94, Issue 5, Pages 2213-2219, May 2011
Effect of storage temperature on quality of light and full-fat ice cream
Authors: J.R. Buyck, R.J. Baer, and J. Choi