Gelling properties of gelatin–xanthan gum systems with high levels of co-solutes

• Large deformation rheological properties of gelatin–xanthan gum and co-solutes were studied.
• XG addition strengthened the network.
• More flexible polymer network was obtained by increasing GS:sucrose ratio.
• Texture maps revealed that systems become rubbery with XG addition.

The effects of moisture content, xanthan gum (XG) addition and glucose syrup (GS):sucrose ratio on elastic (G′) and viscous (G″) moduli during in situ gelation and on large deformation rheological properties of cured gels were investigated. An increase in both moduli of the samples with XG addition indicates network structure being strengthened. All gel samples exhibited distinct fracture. An increase in GS:sucrose ratio led to a decrease in fracture stress and an increase in fracture strain, implying more flexible polymer network. Decreasing moisture content may lead to phase separation between sugar-rich and polymer-rich phases to form stronger connection within the network structure. Textural characteristics of samples analyzed using a texture map, indicated that increasing GS:sucrose ratio rendered the sample texture more rubbery when the samples contained XG. We also related factors affecting the gelling mechanisms in terms of Tg measured by different techniques including DMA and modulated DSC.