A series of co-crystals of vanillic acid (VA) with caffeine (CAF), theophylline (THP), theobromine (THB), nicotinamide (NAM), isonicotinamide (INM), acridine (ACR) and urea (U) have successfully been prepared. The co-crystals involving the methylated xanthines indicate different host: guest ratios with co-crystals VA·2CAF, 2VA·THP and the co-crystal hydrate VA·THB·2H₂O. The nicotinamide and acridine co-crystals (VA·NAM and VA·ACR) displayed 1 : 1 molar ratios in contrast to the isonicotinamide co-crystal hydrate 2VA·2INM·2H₂O. Co-crystallisation of vanillic acid with urea gave 2VA·2U. The co-crystals and co-crystal hydrates were characterised by single crystal X-ray diffraction and thermal analysis. Grinding and slurry experiments were also performed.

Inclusion compounds were formed between the host cyclotriveratrylene, H, (2,3,7,8,12,13-hexamethoxy-5,10-dihydro-15H-tribenzo[a,d,g]cyclononene) and the guests carbon tetrachloride, 1,1,1-trichloroethane, 1,1,1-trichloropropane and 1,1,2-trichloroethane. 1 (H·CCl₄) has guest molecules in channels alternating with channels of host molecules. 2 (H·C₂H₃Cl₃·C₃H₅Cl₃) and 3 (H·2C₂H₃Cl₃) exhibit a slightly different packing arrangement with one guest molecule in the host cavity and the rest of the guest molecules in channels. The stability and reactivity of these inclusion compounds were investigated.

Bambara groundnut (BGN) starch extracted from BGN flour was modified through complexation methods using alpha and beta cyclodextrin. Complexation methods used included the microwave, co-evaporation and kneading methods. Cyclodextrin (alpha and beta) were used as initiators for grafting catechin to the BGN starch molecule. The functional properties of native and modified BGN starches were assessed. The swelling capacity of BGN starches increased with an increase in temperature. The swelling capacities of BGN starches ranged from 0.36 g/g (BGN starch modified through the co-evaporation method, beta cyclodextrin + catechin) to 4.84 g/g (BGN starch modified through the microwave method, beta cyclodextrin + catechin). Complexation methods significantly reduced the swelling capacity of native BGN starch. Temperatures had a significant (p ≤ 0.05) effect on the swelling capacity of BGN starches. The solubility of BGN starches ranged from 0.61 g/100 g (native BGN starch) to 46.04 g/100 g (BGN starch modified through the kneading method, alpha cyclodextrin); using water as a solvent. The water absorption of native and modified BGN starches ranged from 0.23 to 1.17 g/g, respectively. Starches complexed with β-cyclodextrin showed increased water absorption capacity in comparison to the starches complexed with alpha cyclodextrin. The modification methods had a significant (p ≤ 0.05) effect on the water absorption capacities of BGN starches. There was no significant difference in the oil absorption capacities of BGN starches and they ranged from 1.02 to 1.07 g/g. Pasting properties of BGN starches were assessed using a rapid visco analyser (RVA). The modified starches exhibited lower breakdown, setback, and final viscosities as well as significant increase in gelatinisation temperature compared to the native BGN starch.