Preparation of mango kernel fat stearin-based hard chocolate fats via physical blending and enzymatic interesterification

Mango kernel fat-third stearin (MKF-TS) is one of the most valuable cocoa butter improvers. Hard chocolate fats were prepared using MKF-TS, hard palm-mid fraction (HPMF) and cocoa butter (CB) via physical blending and enzymatic interesterification. The optimal physical blend (PB) produced from 10% HPMF, 55% MKF-TS and 35% CB contained 60.9 g/100 g 1,3-distearoyl-2-oleoyl-glycerol, 21.1 g/100 g 1-palmitoyl-2-oleoyl-3-stearoylglycerol and 9.5 g/100 g 1,3-dipalmitoyl-2-oleoylglycerol. The optimal interesterified blend (IB) enzymatically synthesized from 20% HPMF, 60% MKF-TS and 20% CB shared similar triacylglycerol composition to PB. Both PB and IB showed improved thermostabilities compared to CB in terms of sold fat contents, melting and crystallization behaviors. They also exhibited beta polymorphic forms and 50-120 mu m featherlike crystals, which were close to those of CB. The melting of IB tended to be sharper than non-interesterified blend (Non-IB) and its crystals were more continuous and uniform, indicating that enzymatic interesterification is a potential technique for manufacturing hard chocolate fats.