Changing consumers’ taste for chemical and thermally processed food and preference for perceived healthier minimally processed alternatives is a challenge to food industry. At present, several technologies have found usefulness as choice methods for ensuring that processed food remains unaltered while guaranteeing maximum safety and protection of consumers. However, the effectiveness of most green technology is limited due to the formation of resistant spores by certain foodborne microorganisms and the production of toxins. Cold plasma, a recent technology, has shown commendable superiority at both spore inactivation and enzymes and toxin deactivation. However, the exact mechanism behind the efficiency of cold plasma has remained unclear. In order to further optimize and apply cold plasma treatment in food processing, it is crucial to understand these mechanisms and possible factors that might limit or enhance their effectiveness and outcomes. As a novel non-thermal technology, cold plasma has emerged as a means to ensure the microbiological safety of food. Furthermore, this review presents the different design configurations for cold plasma applications, analysis the mechanisms of microbial spore and biofilm inactivation, and examines the impact of cold plasma on food compositional, organoleptic, and nutritional quality.

Berries are delicious and nutritious, making them among the popular fruits. There are various types of berries, the most common ones include blueberries, strawberries, raspberries, blackberries, grapes, and currants. Fresh berries combine high nutritional value and perishability. The processing of berries ensures high quality and enhanced marketability of the product. Sorting, disinfection, and decontamination are essential processes that many types of fruits such as citrus fruits, berries, pomes, and drupes must undergo to ensure improved quality, uniformity, and microbiological safety of the product. Drying and freezing are excellent processing methods to extend the shelf life of berries which also provide new options to the consumer of a wide variety of berries. With the demand for high quality and automatic high-throughput detection of the quality of fruit products, intelligent and rapid detection of various parameters during processing has become the development direction of modern food processing. Therefore, this paper reviews the application of advanced detection technologies, artificial intelligence-based methods for detection and prediction during berry sorting, drying, disinfecting, sterilizing, and freezing processing. These advanced detection techniques include computer vision system, near infrared, hyperspectral imaging, thermal imaging, low-field nuclear magnetic resonance, magnetic resonance imaging, electronic nose, and X-ray computed tomography. These artificial intelligence methods include mathematical modeling, chemometrics, machine learning, deep learning, and artificial neural networks. In general, advanced detection techniques incorporating artificial intelligence have not yet penetrated into all aspects of commercial berry processing, which include drying, disinfecting, sterilizing, and freezing processes.

Food quality and safety are the essential hot issues of social concern. In recent years, there has been a growing demand for real-time food information, and non-destructive testing is gradually replacing traditional manual sensory testing and chemical analysis methods with lagging and destructive effects and has strong potential for application in the food supply chain. With the maturity and development of computer science and spectroscopic techniques, machine learning and hyperspectral imaging (HSI) have been widely demonstrated as efficient detection techniques that can be applied to rapidly evaluate sensory characteristics and quality attributes of food products nondestructively and efficiently. This paper first briefly described the basic concepts of hyperspectral imaging and machine learning, including the imaging process of HSI, the type of algorithms contained in machine learning, and the data processing flow. Secondly, this paper provided an objective and comprehensive overview of the current applications of machine learning and HSI in the food supply chain for sorting, packaging, transportation, storage, and sales, based on the state-of-art literature from 2017 to 2022. Finally, the potential of the technology is further discussed to provide optimized ideas for practical application.

Liposomes provide protection, transport, and delivery systems for drugs and functional ingredients. This review studied liposome-based functional ingredients, effects of electric fields on lipid membranes, methods to determine the degree of electroporation, and some governing equations of the electroporation phenomenon. The objective of this review was to provide an overview of some aspects to consider when designing and manufacturing food liposomes that are stable in electric fields; this was based on studies conducted in medicine, pharmacology, and the food industry. The effects of pulsed electric fields and high voltage electrical discharge processing on phospholipid membranes were studied; these can be extrapolated to liposomes under food processing conditions using electric fields. The chemical compositions of the lipid membrane and adding layers to the liposome surface were related to higher electrical resistance. Fluorescence, impedance, conductivity, and voltage methods were defined to determine the degree of electroporation and mathematical models that can facilitate the analysis of the mechanism. Finally, the study of the electrical properties used by the different materials to manufacture liposomes remains for future research.

Capillary pressure plays a critical role in driving fluid flow in unsaturated porous (pores not saturated with liquids but also containing air/gas) structures. The role and importance of capillary pressure have been well documented in geological and soil sciences but remain largely unexplored in the food literature. Available mathematical models for unsaturated food systems have either ignored the capillary-driven flow or combined it with the diffusive flow. Such approaches are bound to impact the accuracy of models. The derivation of the microscale definition of capillary pressure is overviewed, and the limitations of using the microscale definition at the macroscale are discussed. Next, the factors affecting capillary pressure are briefly reviewed. The parametric expressions for capillary pressure as a function of saturation and temperature, developed originally for soils, are listed, and their application for food systems is encouraged. Capillary pressure estimation methods used for food systems are then discussed. Next, the different mathematical formulations for food systems are compared, and the limitations of each formulation are discussed. Additionally, examples of hybrid mixture theory–based multiscale models for frying involving capillary pressure are provided. Capillary-driven liquid flow plays an important role in the unsaturated transport during the processing of porous solid foods. However, measuring capillary pressure in food systems is challenging because of the soft nature of foods. As a result, there is a lack of available capillary pressure data for food systems which has hampered the development of mechanistic models. Nevertheless, providing a fundamental understanding of capillary pressure will aid food engineers in designing new experimental studies and developing mechanistic models for unsaturated processes.

Process engineering of food materials is strongly associated with their microstructure, which quantification allows proper selection of equipment operating conditions, monitoring sensorial attributes and consumer’s acceptance. This evaluation has been carried out by applying the fractal approach using microscopy images that depict complex, ragged and irregular forms. Therefore, this review aimed to summarise the fundamentals, calculation methods and applications of fractal dimension (FD), lacunarity (\(\Lambda\)) and multifractals for describing the microstructure of selected food systems including the calculation methods derived from the digital image analysis and recent investigations involving the fractal analysis in vegetal materials, animal food products, doughs, gels, starch, food-related micro- and nanoparticles, powders and fats. It was noted that several microscopy techniques were used broadly, and their selection depended on the sample type and specific region of interest. Regarding the calculation of fractal parameters, the box-counting method performed on images of the surface was prevalent in most of the revised pieces of research, finding FD values from 1.60 (for binary images) to 2.99 (for grayscale images). Also, several relationships were found between FD and temperature, composition and textural parameters. It was noted, however, that a specific trend was not detected given that variations in acquisition procedures and observation scale prevailed among the reported works. Besides, it was noteworthy that \(\Lambda\) and multifractals were unexploited, notwithstanding that these fractal properties can aid to achieve a thorough examination of food microstructure. Based on the inspection of fractals in the imaged microstructure, the present review is helpful to improve the management and control of food engineering processes based on food microstructure for obtaining higher quality products.

Food packaging materials are crucial to maintaining food quality, as they play an important role in preventing food deterioration, dehydration, and oxidation. Unlike synthetic polymers, natural biopolymers, such as polysaccharides and proteins, are abundant and widespread resources that are nontoxic, biocompatible, and biodegradable. In food packaging, contact between packaging materials and moist foods can frequently degrade the performance of the materials. This has increased research into the development of hydrophobic biopolymer-based films. Here, we summarize the effective preparation strategies, mechanical and barrier properties, pH responsiveness, self-cleaning performance, and antibacterial and antioxidant functions of hydrophobic biopolymer-based films. The most effective methods for preparing hydrophobic biopolymer-based films are electrospinning with hydrophobically modified biopolymers, adding micro/nanofillers and hydrophobic compounds to the films, and hydrophobically modifying the films. These methods can even generate superhydrophobic films with excellent barrier properties. We also discuss the current opportunities and challenges presented by hydrophobic biopolymer-based films.

Hyperbaric storage (HS) is a developing food preservation technology based on the application of moderate hydrostatic pressure. Having a quasi-zero energetic cost, this technology has been proposed as sustainable alternative to refrigeration. However, despite HS was conceived in 1972, it has not attracted interest of researchers and industries until few years ago. Hence, literature, technical knowledge, and working unit design are still lacking. The purpose of the present review is to provide an overview on hyperbaric storage, highlighting its potentialities as a sustainable food storage technology. Moreover, process constraints and unexplored applications of HS conditions are envisaged. Finally, critical aspects that still need to be investigated are highlighted to provide the foundations for future research. The review of the literature indicates that HS is a promising technology, which could extend food microbiological stability and boost the metabolism of microorganisms involved in biotechnological processes, such as fermentations. HS also affects food matrix biomolecules, with particular reference to protein structures and activity, and lipid physical properties. In the investigated matrices (i.e. plant derivatives, meat, fish, and dairy products), HS produced minor sensory changes. On the other hand, lipid oxidation was significantly increased. Proteins and fat structure modification might be used to tailor food ingredient functionality, opening the way for pioneering HS applications. Nevertheless, still several issues, such as poor technical knowledge, scarcity of investigated food matrices, and lack of appropriate packaging solutions, need to be overcome to make HS industrially viable.

Non-dairy matrices represent 63% of the vehicles used for probiotication. However, their benefits to human health may be hindered by food processing, storage, and movement through the gastrointestinal tract. The microencapsulation of probiotic bacteria is an alternative to increase their resistance to such challenges. This review outlines the current advances in the encapsulation of probiotics using emulsification methods. The review also addresses the influence of encapsulating agents on the yield, the final size of microcapsules, and the survival rate of probiotic microorganisms. The main drying methods for probiotic microparticles, the kind of foods used for probiotication, and the emerging methods of emulsification are discussed. Emulsion microencapsulation has proven to be a viable technique for the production of probiotic microcapsules, while freeze-drying is the most suitable drying technique due to the mild process conditions. Emulsification through membranes and microfluidic devices are potential encapsulation techniques owing to their ability to control particle size and to work under mild conditions. The emulsion microencapsulation is thus a potential technique for ensuring the safe delivery of next-generation probiotics applied to non-dairy products.Graphical Abstract

The processing of selected foods by nonthermal technologies is gaining relevance in the food industry because, in many cases, the final product keeps the nutritional value and other fresh-like characteristics of the original one. There are several nonthermal technologies including high pressure processing, pulsed electric fields, ultrasound, and cold plasma which are at different stages of development. The impact of a given technology on bioactive compounds is a good indicator to assess changes on the nutritional attributes of a given food product before and after processing. Quite frequently, it is mentioned that nonthermal technologies are very appropriate to process foods minimizing changes in quality attributes. This broad claim only applies for certain processing, packaging and storage conditions, and as expected, on the food product. There are extensive scientific publications on how these processes alter the food products, but the reported results have been attained by a disparity of treatments; therefore, comparisons of these results are difficult and sometimes useless. Nevertheless, the gathered information allows to identify, in many cases, valuable trends on how a process affects the different bioactive compounds of a given food product. At the same time, the available data allows to assert, that in general, nonthermal processing is a very sound alternative to conventional thermal treatments to minimize the impact of processing on bioactive compounds. This review summarizes and analyzes the effects of these processes on relevant bioactive compounds present in selected food products as reported in the scientific literature.

Separation of two fluids or particles from an emulsion is a fundamental process in many applications such as creaming of milk in dairy sector and extraction of various oils (avocado oil, palm oil, etc.) among many others. The aim of this paper is to elaborate on the development of various methods and technologies employed for the separation process including gravity, chemical, and centrifugation as well as the newer acoustic separation technology. Influential parameters affecting the performance, advantages, and disadvantages for each method will be discussed and compared. Various transducer configurations and corresponding experimental set-ups and operating parameters are also examined for acoustic separation. Accordingly, the future trend is proposed for introducing new transducer configurations to diminish or preferably eliminate the current disadvantages and barriers and to improve the separation process performance.

Traditionally, the effect of temperature on the rate of biochemical reactions and biological processes in foods, and on the mechanical properties of biopolymers including foods, has been described by the Arrhenius equation which has a single adjustable parameter, namely the “energy of activation.” During the last three decades, this model has been frequently replaced by the WLF equation, borrowed from Polymer Science, which has two adjustable parameters and hence better fit to experimental data. It is demonstrated that the WLF model (and hence also the VTF model) is identical to an expanded version of the Arrhenius equation where the absolute temperature is replaced by an adjustable reference temperature. Both versions imply that the curve describing a process or reaction’s rate rise with temperature or the viscosity or modulus drop with temperature must have the same characteristic upper concavity above and below the glass transition temperature, Tg, however it is defined and determined. Nevertheless, at least some reported experimental data recorded at or around the transition regime suggest otherwise and in certain cases even show concavity direction inversion. The mathematical description of such relationships requires different kinds of temperature-dependence models, and two such alternatives are described. Also suggested are two different ways to present the temperature as a dimensionless independent variable which enables to lump and compare different transition patterns in the same graph. The described approach is purely formalistic; no fit considerations are invoked and neither model is claimed to be exclusive.

Air source heat pump drying systems in the agricultural production sector were reviewed in this study in terms of optimal designs, leading to the optimization of the heat pump drying process. Several intricate designs have been used to optimize the heat pump drying process. Multiple evaporators with multiple condensers, multiple drying chambers, cascade heat pump drying systems, hybrid heat pump drying systems, different configurations of the heat pump components, and refrigerants with lower environmental impacts have been used to accomplish optimal heat pump dryer designs and thereby optimum drying conditions for agricultural products.

The response of microorganisms to chemical preservatives and disinfectants can be described by the traditional Chick-Watson-Hom’s (CWH) model or more general Weibullian survival model, of which it is a special case. The chemical agent efficacy and its concentration dependence can be described by either a power-law or log-exponential term. For dynamic inactivation, the unstable or volatile agent’s dissipation can be described by a flexible two-parameter model, which is inserted as an algebraic term into the differential rate equation. In principle, both models can be used to estimate a targeted microbe’s survival parameters from the agent’s concentrations when constant or its initial and final concentrations only if not, and the corresponding final survival ratios reached. This Endpoints Method eliminates the need to determine the entire survival curves, and in the dynamic case the agent’s entire dissipation curves too. Static inactivation requires the numerical solution of simultaneous nonlinear algebraic equations, and dynamic, of simultaneous nonlinear equations whose right-hand side is the numerical solution of differential rate equations in which the agent’s dissipating pattern is incorporated as a term. When the Weibullian survival model’s shape factor is known a priori, the theoretical minimum of experimental final survival ratios needed is two and when unknown three. However, validation of the model and mathematical procedure must come from their ability to predict correctly final survival ratios not used in the parameter magnitudes calculation, which requires at least one additional experimental final survival ratio determination.

Whey is a by-product of cheese, casein, and yogurt manufacture. It contains a mixture of proteins that need to be isolated and purified to fully exploit their nutritional and functional characteristics. Protein-enriched fractions and highly purified proteins derived from whey have led to the production of valuable ingredients for many important food and pharmaceutical applications. This article provides a review on the separation principles behind both the commercial and emerging techniques used for whey protein fractionation, as well as the efficacy and limitations of these techniques in isolating and purifying individual whey proteins. The fractionation of whey proteins has mainly been achieved at commercial scale using membrane filtration, resin-based chromatography, and the integration of multiple technologies (e.g., precipitation, membrane filtration, and chromatography). Electromembrane separation and membrane chromatography are two main emerging techniques that have been developed substantially in recent years. Other new techniques such as aqueous two-phase separation and magnetic fishing are also discussed, but only a limited number of studies have reported their application in whey protein fractionation. This review offers useful insights into research directions and technology screening for academic researchers and dairy processors for the production of whey protein fractions with desired nutritional and functional properties.

Based on the design of printing models, three-dimensional (3D) and four-dimensional (4D) printing technologies have shown extensive and promising application potential in the food industry. The majority of previous researches on printing models focus on single or multiple models to test the performance of printers and inks, assess the influence of printing parameters on product performance, and print new products. This review compares the differences between the recently proposed 3D/4D printing models and summarizes the key factors needing to be considered in model design. The solid models are mainly used to explore printing parameters, while the filling models are used to study the texture characteristics of food. Models with changing shapes or colors reflect the importance of model structural design. The reasons for distortion in the process of transition from digital models to food models are analyzed, and the corresponding solutions are proposed. In the future, it is necessary to expand model database and develop cloud platform services so as to facilitate the sharing of related resources and strengthen the personalized nutrition of different consumer groups.

Tea (Camellia sinensis) is the most widely consumed beverage in the world, with an excellent source of bioactive compounds such as catechins, caffeine, and epigallocatechin. There is an increasing trend to extract these bioactive compounds to deliver them as value-added products. Generally, the extraction of polyphenols and other functional compounds from different parts of tea is carried out using different solvents (e.g., water, water–ethanol, ethanol, methanol, acetone, ethyl acetate, and acetonitrile). The extraction efficiency of functional compounds from tea depends on the type and polarity of the solvent as well as the applied process. Several conventional techniques, such as boiling, heating, Soxhlet, and cold extraction, are used to extract bioactive ingredients. However, these procedures are unsuitable for achieving high yields and biological activities due to the long extraction times of cold brewing and the high temperatures in other heating methods. Many efforts have been carried out in food and pharmaceutical industries to replace conventional extraction techniques with innovative technologies (e.g., microwave (MAE), ultrasonic (UAE), pressurized liquid (PLE), pulsed electric field (PEF), and supercritical fluid (SFE)), which are fast, safe, energy-saving, and can present eco-friendly characteristics. These innovative extraction techniques have proven to improve the recovery rate of phenolic-based antioxidant compounds from tea and increase their extraction efficiency. In this review, the application of novel processing technologies for the extraction of value-added compounds from tea leaves is reviewed. The advantages and drawbacks of using these technologies are also highlighted.

The application of hurdle interventions can improve microbial efficacy as well as ensure food quality. Light-emitting diodes (LEDs), as a promising non-thermal food preservation technology, have increasingly attracted attention in the food industry; however, the technology possesses certain limitations that have impeded widespread adoption by the food industry. In recent years, the combination of LEDs with other intervention strategies (e.g., exogenous photosensitizers, traditional, and novel approaches) has been proposed and attracted much interest. This review aims to provide a comprehensive summary of the current status of LED-based hurdle technologies in the food industry. The review focused on the combined effect and mechanism of different hurdles and LEDs in improving food safety. In addition, the potential as a pre-treatment tool for LEDs was also evaluated for their ability to reduce microbial resistance to other interventions. Finally, some critical issues and challenges have been proposed to be addressed to ensure the efficacy and safety of LED-based hurdles in food systems.

The first-order kinetics for microbial inactivation was derived more than 100 years ago and is still used, although more and more researchers are aware of very common non-linear survival curves. The Weibull model is just a simple alternative to the linear model and can be used to describe convex, concave, and linear survival curves. The objective of this review is not to criticize the first-order kinetics or to praise the Weibull model. In this review, the Peleg and Mafart versions of the Weibull model were compared with emphasis on the parameters of those model expressions, the scaled sensitivity coefficients of the model parameters, and the dependency of the model parameters to each other. Secondary modeling was also considered. It was concluded that both Peleg and Mafart versions can be safely used to describe linear and non-linear (convex or concave) survival curves under constant conditions. However, concerning the secondary model, predictions under dynamic conditions, and availability of an Excel®-based workbook for this purpose, the Peleg model seemed to be one step ahead. One of the parameters of the Weibull model and the secondary model derived from this parameter could be used as an alternative to the conventional D value. This work confirms that the Weibull model can serve as the microbial survival model instead of the now obsolete linear model whatever the lethal treatment is.

The annual global amount of water consumed to produce food ranges from 600,000 to 2.5 million liters per capita depending on food habits and food waste generation. Humans need approximately 2–3 L of water daily to maintain health, but only 0.01% of the world’s water is drinkable. Food supplies cannot be generated without land, water, and energy use. The current use of water for production of food is most concerning and requires immediate and increased awareness. Minimal attention has been devoted to the increasing water scarcity and loss of drinking water. Food waste also contains water and therefore also adds to water scarcity that is affecting almost 4 billion people. We summarize the human need of water, its significance for life and for the production, processing, and consumption of foods. This review includes an examination of the history of water; the unique properties of water for sustaining life; water for food production including agriculture, horticulture, and mariculture; the properties of water exploited in food processing; water scarcity due to water demands exceeding availability or access; and its consequences for our world. Means to reduce water scarcity, including using water treatment and promoting change of human habits, are discussed. The future of water and the recommendations for action are proposed for decreasing water scarcity and reducing water use during food production, food processing, food preparation, and consumption.