WEST LAFAYETTE, IND. — A study conducted by Purdue University, West Lafayette, and published in the Journal of Food Science uncovered answers to why food ingredient blends are more sensitive to climate changes than single ingredients.
“Blending crystalline ingredients such as salt and sugar with amorphous solids (without uniform shape) such as proteins, starch-based ingredients, and gums destabilizes the ingredients when heated or exposed to increasing humidity,” said Lisa Mauer, professor of food science, Purdue. “This can be frustrating to food formulators and consumers alike.”
Ms. Mauer’s previous research focused on the deliquescence of crystalline ingredients. She identified the humidity levels at which crystalline ingredients begin to dissolve. Formulators looking to prevent deliquescence need to keep the humidity below a certain threshold, which becomes more difficult when amorphous ingredients are added.
“Picture amorphous ingredients as little sponges,” Ms. Mauer explained. “These sponges absorb water from the environment and their texture changes.”
The Purdue study is the first to identify the exact crossover point between the crystalline ingredient deliquescence point and amorphous ingredient water activity. The blends studied included ingredients found cake mixes, vitamin preblend mixes and snack flavoring powders.
Findings in the study have broad implications for companies who ship their food products to grocery or retail channels, encounter wide climate variances while in transit.
“While the moisture sorption-related problems can be solved by packaging ingredient blends in individual serving sizes, this approach increases costs and the environmental burden associated with packaging and does not solve the enhanced temperature-sensitivity of the ingredient blends,” Ms. Mauer said.
Other findings of the study include the moisture sorption properties of tested ingredients, how deliquescence points of crystalline ingredients and water activities of amorphous ingredients are affected by temperature and how ingredient blends are affected by various environments over time. It also shed light on the physical state and thermal properties of ingredients and blends by using powder x-ray diffraction and differential scanning calorimetry.
Ms. Mauer elaborates on her research in a video produced by the Journal of Food Science called Take 5 for Food Science.