Developments such as the Common Agricultural Policy reform, growth of the bio‐based economy, increasing energy prices, increasing sustainability demands, and expected growth of global sugar demand change the environment in which the sugar producing industry operates. In order to remain competitive and profit from this, the traditional large‐scale sugar producing industry can adapt. The aim of this study was to address sustainability and energy issues of the traditional sugar production process and to provide opportunities for improving the process and value chain. The methodological approach included evaluating function and resource usage of the unit operations. More sustainable alternative unit operations and processes were identified and studied. The results indicate that the current sugar production and by‐product valorization focuses on centralized processing and has been individually optimized per sector and industry based on relatively inexpensive transportation and energy without a focus as such on the bio‐based economy. For incorporation of the opportunities, a process for targeting new bio‐based markets and supplementing large‐scale sugar production was designed. It was found that small‐scale biorefineries as an alternative and/or supplementation of the traditional large‐scale process have the ability to increase the overall sustainability of sugarbeet processing, for example reduce energy usage and carbon footprint, by reducing transportation movements. Moreover, it provides opportunities for leaving out certain unit operations and using less capital‐intensive technologies. With a holistic approach throughout the value chain, the introduction of small‐scale biorefineries can help meet the challenges of the sugar producing industry, while simultaneously benefitting people, planet, and profit.

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Amino acids are important in human and animal diet, as well as being potential feedstocks for chemical production. Amino acids can be obtained from protein after hydrolysis. In addition, several agro-industrial residues already contain a mixture of free amino acids. The objective of this study was to develop a method for amino acids separation, starting from mixtures containing amino acids, and using antisolvent precipitation with ethanol. Protamylasse, rubber seed protein hydrolysates, and grass juice were used in the experiments, representing existing and potential agro-industrial residues. Our results show that in a water–ethanol system, some amino acids had lower solubility in mixtures than as a single component, thereby facilitating precipitation. A sufficiently high total amino acid concentration in the mixture is needed to achieve precipitation; therefore, a concentration step is sometimes required. Ethanol precipitation can be applied as a pretreatment to separate mixtures into groups of amino acids or a polishing step to increase purity.

Processes such as chromatographic separation and nanofiltration can remove low molecular weight sugars from liquid mixtures of oligosaccharides. As an alternative for the separation of such liquid mixtures, we studied mass diffusion separation of such sugars in a microfluidic device with incorporated nanofiltration membranes. This separation method is based on differences between diffusivities of components and does not require high transmembrane pressures. The effects of channel depth and flow rate were studied in experiments. The key parameters selectivity and rejection increased with increasing channel depth due to increased external mass transfer limitations. Among the studied membranes, the obtained selectivities and rejections correlated to the specified retention values by the manufacturers. Compared to more conventional nanofiltration where high pressure forces solutes through membranes, we obtained corresponding selectivities and fluxes of only an order of magnitude smaller. Simulated results indicated that with optimized microchannel and membrane dimensions, the presented separation process can compete with currently available separation technologies.

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