Emerging technologies in food and drink production
Emerging technologies such as high-pressure processing (HPP) are now well established for achieving products with ‘fresh’ like properties, but with a shelf life of weeks or months rather than days. But more recently, technologies such as HPP and power ultrasound are also being used to change the properties of foods, to give an improved or novel product. Our ‘new technologies’ project has been evaluating many of these processing methods for over a quarter of a century, as the examples below illustrate.
There is a growing focus on a structured approach to NPD to optimise appeal and the chances of success in a competitive market, especially given the squeeze on product launch timelines. Reliable insight into what consumers want from products – derived from a rigorous, structured approach – is essential.
HPP can preserve the organoleptic properties of fresh products by providing a microbiological reduction treatment without the associated thermal quality changes. HPP is now a mature technology and has reached the point where, rather than addressing scientific fundamentals, technologists are interested in the practical implementation, validation and management of HPP manufacturing. When validating HPP processes, a clear understanding of factors which could impact on process lethality is required. Factors such as pH and water activity are important as well as strain selection and growth phase. Maintenance and hygiene management of HPP equipment needs to be effectively managed. Previous work, for example, has highlighted that higher bacterial counts are associated with the sealing arrangement and closures of the HPP vessel.
The viscosity of a food can significantly affect processing efficiency. The effect of power ultrasound on hydrated solutions of thickening agents and food products was studied. A thinning effect of the ultrasound treatment was observed in a gelatinised starch solution, a mushroom sauce and a fruit preparation. The level of viscosity reduction depended significantly on the amplitude. In the three model systems, the modification of the sample viscosity was partially or fully reversible. A significant increase in viscosity after treatment (up to 62%) was observed in tomato paste, with the effect depending on treatment time. Reversible modification of viscosity could help optimise processes such as spray drying and filtration.
Uptake of robotics for food manufacturing is limited, and has primarily focused on end-of-line packaging handling. Increased automation is now leading to robots being used for food handling applications. A feasibility study investigated microbial build up on 3 different grippers and product during simulated production and looked at potential cross contamination using fluorescent dyes. Prolonged operation of the gripper handling the contaminated food product was necessary to understand where the microbial build-up might occur during production. There was no statistically significant effect on microbial counts in food of using vacuum and Bernoulli grippers, but contact grippers did result in greater microbial counts, suggesting that build-up on the gripper claws could also cause an increased microbial loading on the product over time.