Moisture sorption characteristics of crystalline and amorphous 2'-fucosyllactose, a human milk oligosaccharide

Sungahm Ahn; Hee Chung; Dong Zhao; Donghwa Chung

doi:10.1016/j.foodchem.2024.142505

Moisture sorption characteristics of crystalline and amorphous 2'-fucosyllactose, a human milk oligosaccharide

Food Chem. 2024 Dec 16:468:142505. doi: 10.1016/j.foodchem.2024.142505. Online ahead of print.

Authors

Sungahm Ahn¹, Hee Chung², Dong Zhao³, Donghwa Chung⁴

Affiliations

¹ Food Technology Major, Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Republic of Korea; CJ BIO Research Institute, CJ CheilJedang, Suwan 16495, Republic of Korea.
² Institute of Food Industrialization, Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea.
³ Sericultural and Agri-Food Research Institute, Guangdong Academy of Agricultural Sciences/Key Laboratory of Functional Foods, Ministry of Agriculture and Rural Affairs/Guangdong Key Laboratory of Agricultural Products Processing, Guangzhou 510610, China.
⁴ Food Technology Major, Graduate School of International Agricultural Technology, Seoul National University, Pyeongchang 25354, Republic of Korea; Institute of Food Industrialization, Institutes of Green Bio Science and Technology, Seoul National University, Pyeongchang 25354, Republic of Korea; Center for Food and Bioconvergence, Seoul National University, Seoul 08826, Republic of Korea. Electronic address: dchung@snu.ac.kr.

PMID: 39700813
DOI: 10.1016/j.foodchem.2024.142505

Abstract

The moisture sorption characteristics of crystalline and amorphous forms of 2'-fucosyllactose (2'-FL) were investigated and compared with those of two forms of lactose. The moisture sorption isotherms showed that, relative to crystalline α-lactose monohydrate (α-LM), crystalline 2'-FL was more susceptible to moisture sorption. Crystalline 2'-FL exhibited a lower deliquescence point (89.8 %) but threefold greater water solubility (57.1 %) than crystalline α-LM at 25 °C. Time-dependent moisture sorption, X-ray diffraction, and scanning electron microscopy analyses confirmed that amorphous 2'-FL underwent moisture-induced crystallisation (similar to amorphous lactose), but required more humid conditions (a_w > 0.53; a_w > 0.33 for amorphous lactose) due to lower molecular mobility. Dynamic oscillatory rheology showed that amorphous 2'-FL exhibited a higher sticky point temperature (T_s) compared with amorphous lactose at any given a_w, and T_s decreased from 78.9 °C to 43.6 °C as a_w increased from 0.23 to 0.53 due to the plasticizing effect of moisture.

Keywords: 2′-Fucosyllactose; Crystallisation; Deliquescence; Moisture sorption; Stickiness.