Oil Syneresis

Nut butters are becoming increasingly popular and are advertised as ‘superfoods’ with a high content of proteins, unsaturated fatty acids, vitamins, minerals and trace elements. In addition to traditional peanut butter, almond, hazelnut and cashew butter are the favorite varieties. The shelf life of nut butters is significantly limited by oil syneresis. The oil released from the nuts after processing often separates and collects on the surface – the so called “oil syneresis”. The speed and extent of oil syneresis depends on the quality, ageing and composition of the raw materials. Processing (thermal and mechanical treatment) also has an effect on oil syneresis in the product. Less oil syneresis means better acceptance and marketability.

The interaction of frequently used analytical methods (gas chromatography, Soxhlet extraction, rheology and NMR (Nuclear Magnetic Resonance)) that are to be developed should provide insights into the development of oil syneresis in order to be able to make predictions in the aforementioned parameter field. Rheo-NMR in particular is suitable for simulating and analyzing the crushing and stirring process for nut butter under mechanical stress. A simple, robust NMR method in QC-capable low-field NMR, which detects oil syneresis before it is optically visible, is being developed and established.

Companies, and Small and medium-sized enterprises (SMEs) in particular, can only compete in this environment if they offer innovative products with added value and exceptional quality. A better understanding of the oil syneresis tendency in crushed nuts and nut butters can help SMEs to develop recipes more effectively and to adapt manufacturing processes, reduce storage trials and speed up product development.