Design and functionality of a prototype for cold needle perforation of wheat

Wheat is a vital crop in global food security, but up to 25% of the wheat harvested is contaminated with mycotoxins that have detrimental effects on human health. To address this issue, biological detoxification strategies have been developed using microorganisms and enzymes. Perforating the whole wheat kernel using cold needle perforation (CNP) followed by a detoxification step could be a promising approach to reduce cross-contamination during the milling of mycotoxin-containing wheat. In this study, a pilot-scale CNP prototype was developed to perforate wheat kernels, and its effectiveness was evaluated. The height-adjustable perforation unit consists of 3120 needles. The throughput of the CNP prototype was adjusted to 6 kg/h, and the kernels were perforated for 1, 5, or 10 cycles. The results show that the CNP prototype effectively perforates wheat kernels, as evidenced by the significant increase in pore count. Fluorescence microscopy confirmed the penetration of particles in the size range of enzymes and microorganisms into the kernel. This study demonstrates the successful scale-up of CNP for wheat kernel perforation and highlights the potential of CNP as a cost-effective and efficient method for the biological detoxification of mycotoxin-contaminated wheat

Effectiveness of perforation methods for wheat kernels

Wheat is an important staple food worldwide, but often contaminated with moulds, which in specific cas es, form toxic mycotoxins as secondary metabolites. The aim of this study was to investigate different pre processing methods of wheat kernels that allow active agents such as functional microorganisms and en zymes to pass through the water-repellent hyaline layer in order to break down possible mycotoxins into less or non-toxic compounds. To be able to assess the processing efficacy, a qualitative visualisation meth od was developed and implemented. A wide range of processing techniques to perforate the outer layers while maintaining structural integrity of the kernel were tested, including ohmic heating, pulsed electric fields (PEF), ultrasonication, cold needle perforation (CNP), heat stress and steam explosion. It was shown that both the application of PEF as well as CNP are promising paths to perforate the outer wheat layers. The effectiveness of CNP was shown through a combined microscopic approach involving scanning elec tron microscopy and fluorescence microscopy with fluorescing particles in the size range of both enzymes and lactic acid bacteria