3D printing, also referred to as additive manufacturing, offers a wide range of new processing possibilities to the food industry. This technology allows a layer by layer (bottom to top) printing of predefined slices of designed and desired objects. 3D printing potentially allows rapid manufacturing of complex objects, which are unhindered by design complexity, thus providing substantial liberty to create new and untested geometric shapes. In terms of food manufacturing, the potential that 3D food printing technologies can bring may revolutionize certain aspects of food manufacturing, providing the convenience of low-cost customized fabrication and even tailored nutrition control. The most common materials suitable for 3D food printing are carbohydrate, fat, protein, fiber and functional components. In the present study, the characteristics of raw materials or additives used during 3D printing, and requirements for estimating and improving their printing performance and self-supporting ability in extrusion-based printing regarding rheological characteristics of 3D food printing materials are reviewed. As an innovative process, 3D food printing may induce a revolution in certain areas of food manufacturing.

As an efficient heating method, microwave processing has attracted attention both in academic research and industry. However, the mechanism of dielectric heating is quite distinct from that of the traditional conduction heating, and is widely applied as polar molecules and charged ions interaction with the alternative electromagnetic fields, resulting in fast and volumetric heating through their friction losses. Such a heating pattern would cause a certain change in microwave treatment, which is an unarguable reality. In this review, we made a retrospect of the essential knowledge about dielectric properties and summarized the concept of microwave heating, and the impact of microwave application on the main components of foods and agricultural products, which are classified as carbohydrates, lipids, proteins, chromatic/flavor substances, and vitamins. Finally, we offered a way to resolve the drawbacks of relevant microwave treatment and outlined the directions for future research.

Salmonellosis outbreaks related to consumption of raw almonds have encouraged the scientific community to study the inactivation kinetics of pathogens in this dry commodity. However, the low moisture content of the product presents a challenge for thermal control, because the time required to achieve the desired thermal inactivation of microorganisms increases sharply with reduced moisture content and water activity. In this study, we explored and modeled the heat inactivation of Salmonella enterica serovar Enteritidis PT 30 in almond cultivar 'Nonpareil' kernel flour at four water activity (a(w)) values (0.601, 0.720, 0.888, and 0.946) using four temperatures for each a(w). The results showed that the inactivation was well fitted by both Weibull distribution (R(2) = 0.93 to 1.00) and first-order kinetics (R(2) = 0.82 to 0.96). At higher a(w) values, the rate of inactivation increased and less time was needed to achieve the required population reduction. These results suggest that, to avoid deterioration of product quality, shorter process times at lower temperatures may be used to achieve desired inactivation levels of Salmonella Enteritidis PT 30 by simply increasing the moisture content of almonds. These goals could be achieved with the use of existing procedures already practiced by the food industry, such as washing or prewetting scalding before heat inactivation.