Effects of Cross-Linking on Physicochemical and Film Properties of Lotus (Nelumbo nucifera G.) Seed Starch

Ankita Chandak; Sanju Bala Dhull; Sneh Punia Bangar; Alexandru Vasile Rusu

doi:10.3390/foods11193069

Effects of Cross-Linking on Physicochemical and Film Properties of Lotus (Nelumbo nucifera G.) Seed Starch

Foods. 2022 Oct 3;11(19):3069. doi: 10.3390/foods11193069.

Authors

Ankita Chandak¹, Sanju Bala Dhull¹, Sneh Punia Bangar², Alexandru Vasile Rusu^{3

4}

Affiliations

¹ Department of Food Science and Technology, Chaudhary Devi Lal University, Sirsa 125055, India.
² Department of Food, Nutrition and Packaging Sciences, Clemson University, Clemson, SC 29631, USA.
³ Life Science Institute, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania.
⁴ Animal Science and Biotechnology Faculty, University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca, 400372 Cluj-Napoca, Romania.

Abstract

Lotus seed starch was cross-linked using sodium trimetaphosphate (STMP) in varying amounts (1, 3, and 5%), and its rheological, pasting, thermal, and physicochemical properties were investigated. These cross-linked lotus seed starches (CL-LS-1, CL-LS-3, CL-LS-5) were also used to produce films (CL-LSFs), which were then examined for their mechanical characteristics, water vapor permeability, moisture content, opacity, thickness, and water solubility. After cross-linking, the solubility, amylose content, and swelling power of all the starch samples decreased. Cross-linking resulted in an increased pasting temperature, while peak viscosity (PV) decreased, with CL-LS-5 exhibiting the lowest peak viscosity (1640.22 MPa·s). In comparison to native starch, the thermal characteristics of CL-LS demonstrated greater gelatinization temperatures (T_o, T_p, T_c) and gelatinization enthalpy (ΔH_gel). The gelatinization enthalpy of CL-LS varied between 152.70 and 214.16 J/g, while for native LS the value was 177.91 J/g. Lower moisture content, water solubility, and water vapor permeability were observed in the CL-LSFs. However, the cross-linking modification did not produce much effect on the film thickness. The highest tensile strength (12.52 MPa) and lowest elongation at break (26.11%) were found in CL-LSF-5. Thus, the starch films' barrier and mechanical qualities were enhanced by cross-linking.

Keywords: cross-linking; edible film; lotus seed starch; properties.

Grants and funding

The APC was supported by a grant from the Romanian National Authority for Scientific Research and Innovation, CNCS-UEFISCDI, project number PN-III-P2-2.1-PED-2019-1723 and PFE-14, within PNCDI III.