Numerical simulations of pulsed electric fields for food preservation: A review

The application of pulsed electric fields is a novel technique to preserve foods in a non-thermal way. One key component of this technology is the treatment chamber, in which the food is exposed to a pulsed electric field to induce permeabilization of biological cells, e.g. to inactivate microorganisms. For a high efficiency of the method and a high product quality a detailed knowledge of the electric field strength and temperature distribution in the chamber is necessary. The numerical simulation of the fluid dynamics coupled with the electric and thermal fields inside the treatment chamber can provide such information with high spacial and temporal resolution. An important goal of the simulations is the optimization of the treatment chamber geometry to improve the uniformity of the electric and thermal fields between the electrodes in order to avoid the over or under-processing of foods or dielectric breakdowns. This article reviews numerical investigations performed on the pulsed electric field process and presents numerical results of a treatment chamber optimization and the solution of coupled fluid dynamical, electrical and thermal problems.

Industrial relevance:

Numerical simulations of the pulsed electric field process provide detailed information of the fluid flow, the temperature and the electric field distributions in treatment chambers under various conditions. Such local information inside the electric field is difficult to obtain experimentally. For a further development of the pulsed electric field technology, numerical simulations can be applied to improve the fundamental understanding of the physical phenomena occurring and to optimize the process with respect to the chamber design and operating conditions.     

高强脉冲电场对食品成分的影响

强脉冲电场是近年来发展起来的一项非热食品绿色加工新技术,有望取代传统热处理技术,从而引起了业内广泛关注。本文综述了强脉冲电场处理对液态食品品质和成分的影响,与热处理相比,强脉冲电场处理具有保存食品原有风味和营养价值的特性。      

Recent advances in phosphorylation of food proteins: A review

Phosphorylation is a useful method for improving the functional properties of food proteins. In this article, various methods of phosphorylation are reviewed. Dry-heating phosphorylation, a method developed recently, is also introduced. Some characteristics of phosphate groups are involved, and the effects of phosphorylation on the structural changes, the functional properties, and the physiological functions in vitro of food proteins, are discussed. The types of phosphate linkages and the phosphopeptides from phosphorylated proteins are identified. The molten (partially unfolded) conformations of food proteins formed by phosphorylation are discussed. The phosphorylation of food proteins improved a number of functional properties, including heat stability, emulsifying properties, foaming properties, gelling properties, water absorption capacity, oil absorption capacity, and calcium phosphate-solubilizing ability. In vitro physiological function studies of protein (α-lactoalbumin) indicated that the digestibility (ovalbumin) was improved and the inflammatory response (α-lactoalbumin) was suppressed by phosphorylation. Experiments with animals are necessary to evaluate the toxicity and physiological functions of phosphorylated proteins.     

计算流体动力学在食品热处理中的应用

简要介绍了计算流体动力学(CFD)在食品热处理中的求解过程、软件结构及常用软件,并对CFD模拟食品焙烤与热杀菌过程的相关研究进行了综述,同时总结了CFD的优点与不足,并展望了其在食品热处理中的发展与应用前景。      

Modification of plant proteins for improved functionality: A review

The market trend towards plant-based protein has seen a significant increase in the last decade. This trend has been projected to continue in the coming years because of the strong factors of sustainability and less environmental impact associated with the production of plant-based protein compared to animal, aside from other beneficial health claims and changes in consumers' dietary lifestyles. In order to meet market demand, there is a need to have plant-based protein ingredients that rival or have improved quality and functionality compared to the traditional animal protein ingredients they may replace. In this review article, we present a detailed and concise summary of the functionality challenges of some plant protein ingredients with associated physical, chemical, and biological processing techniques (traditional and emerging technologies) that have been attempted to enhance them. We cataloged the differences between several studies that seek to address the functionality challenges of selected plant-based protein ingredients without overtly commenting on a general technique that addresses the functionality of all plant-based protein ingredients. Additionally, we elucidated the chemistry behind some of these processing techniques and how they modify the protein structure for improved functionality. Although, many food industries are shifting away from chemical modification of proteins because of the demand for clean label product and the challenge of toxicity associated with scale-up of this technique, so physical and biological techniques are widely being adopted to produce a functional ingredient such as texturized vegetable proteins, hydrolyzed vegetable protein, clean label protein concentrates, de-flavored protein isolates, protein flour, and grits.     

Interactions between proteins and phenolics: effects of food processing on the content and digestibility of phenolic compounds

Phenolic compounds have recently become one of the most interesting topics in different research areas, especially in food science and nutrition due to their health-promoting effects. Phenolic compounds are found together with macronutrients and micronutrients in foods and within several food systems. The coexistence of phenolics and other food components can lead to their interaction resulting in complex formation. This review article aims to cover the effects of thermal and non-thermal processing techniques on the protein–phenolic interaction especially focusing on the content and digestibility of phenolics by discussing recently published research articles. It is clear that the processing conditions and individual properties of phenolics and proteins are the most effective factors in the final content and intestinal fates of phenolic compounds. Besides, thermal and non-thermal treatments, such as high-pressure processing, pulsed electric field, cold plasma, ultrasonication, and fermentation may induce alterations  in those interactions. Still, new investigations are required for different food processing treatments by using a wide range of food products to enlighten new functional and healthier food product design, to provide the optimized processing conditions of foods for obtaining better quality, higher nutritional properties, and health benefits. © 2024 Society of Chemical Industry.     

高压脉冲电场杀菌技术在紫菜食品加工中的应用

高压脉冲电场(PEF)用于食品杀菌具有时间短、能耗低、能有效保存食品营养成分和天然色、香、味特征,非常具有工业化前途。本文是高压脉冲电场(PEF)在食品杀菌中的实践及它在工业生产加工中的应用。鲜紫菜加工厂应用PFE杀菌的技术工艺过程,设备的选型,参数设计。以往高压脉冲电场(PEF)技术多数停留在实验研究阶段,实际生产中的应用不多,此项目是对高压脉冲电场(PEF)杀菌技术的集成实施,从生产反馈中获得优化数据,有较好的推广前景。     

Effects of thermal processing on antioxidant activities,amino acid composition and protein molecular weight distributions of jasmine rice bran protein hydrolysate

This research aimed to evaluate the effects of thermal processing on the amino acid composition, molecular weight distribution (MW) and antioxidant activities of Jasmine rice bran protein hydrolysates (JBH). JBH was prepared by enzymatic hydrolysate (alcalase and flavourzyme at a ratio of 9.81:90.19, 2.84% w/w) for 60 min. JBH samples were treated as follows: non-heat (NJBH), pasteurisation (72ºC, 15 min; PJBH) and sterilisation (121ºC, 15 min; SJBH). For SJBH treatment, the browning index and fluorescence intensity increased (P < 0.05). FTIR showed that thermal process changed the intensities and location of some bands. Thermal processing affected MW by decreasing it from high MW (>10 kDa) to medium (3–10 kDa) and low MW (<3 kDa). Val, Met, Ile and Leu contents increased after thermal processing. Compared with NJBH, the IC₅₀ values of ABTS and FRAP of SJBH were not significantly different, while the IC₅₀ of DPPH increased (P ≥ 0.05).     

植物蛋白高湿挤压组织化综述

随着社会发展进步,营养、健康的生活理念以及可持续发展的人文环境越来越受到认同。组织化植物蛋白因其营养丰富、绿色环保而广受关注,其工业生产近年来发展迅猛。高湿挤压工艺可以使组织化植物蛋白具有更类似肉的纤维状组织结构,是目前人造肉加工技术及产业关注的焦点。高湿挤压过程涉及分子的复杂构象改变与理化变化,且影响产品最终品质的因素众多、复杂。如何理清机理,控制条件,优化工艺仍是一大挑战。本综述旨在梳理高湿挤压技术的发展,归纳设备、工艺及机理研究的主要进展,重点分析在此技术中原料、温度、水分含量、进料速度和螺杆转速对产品品质的影响,描述挤压后产品的性质特性,为高湿挤压技术生产组织化植物蛋白的发展提出建议与展望。     

Investigating consumers' perception of apple juice as affected by novel and conventional processing technologies

This work evaluates consumers' perception of apple juice processed by high pressure processing (HPP) and pulsed electric field (PEF) compared with thermal processing. As a case study, young Chinese immigrants living in New Zealand were selected. Targeting a broad understanding of process impact, three industrially relevant apple cultivars (New Zealand Jazz, Rose and Granny Smith) were chosen. The consumer study was performed using napping with ultra‐flash profiling technique (n = 38). The process impact on sensory perception seems to vary among the investigated apple cultivars. For Jazz and Granny Smith apple cultivars, PEF‐ and HPP‐treated juices are perceived as fresh, natural, sweet and balanced flavour. For Rose apple cultivar, however PEF‐processed juices appear to be perceived as fresh flavour in comparison with HPP and thermally treated juices. Moreover, thermal processing caused cooked flavour. With respect to colour, immediately after processing, HPP retains the natural apple juice colour compared with other treatments.     

非热加工技术消减食物过敏原研究进展

主要介绍了低温等离子体技术、高压处理、超声波处理、辐照处理等非热物理加工技术及其优缺点,这些技术均能够通过暴露或掩盖食物中过敏原的抗原表位,改变过敏原的二级结构,破坏维持三、四级结构的非共价键如氢键、疏水相互作用等方式来改变致敏蛋白的空间结构,从而消减其致敏性。     

Bacillus Spores in the Food Industry: A Review on Resistance and Response to Novel Inactivation Technologies

The importance and challenges presented by Bacillus spores in the food industry are briefly outlined with a focus on Bacillus cereus. The structure and the mechanism of resistance exhibited by Bacillus spores are described, and the steps involved in their germination are included. Novel technologies, using no or only mild heat treatments, to inactivate Bacillus spores are covered, including ultraviolet radiation, pulsed electric field, and high‐pressure processing, both as stand‐alone techniques or techniques as part of a hurdle approach.     

Efficient and robust multi-objective optimization of food processing: A novel approach with application to thermal sterilization

The optimization of thermal processing of foods is a topic which has received great attention during the last decades. The majority of the authors have considered the use of single-objective (criteria) for the optimization. However, the simultaneous optimization of several objectives is much more realistic and desirable, but the associated non-linear programming problems can be very challenging to solve. Here, we describe an efficient and robust multi-criteria optimization method which can be successfully applied to large dynamic systems, like those arising from the modelling of thermal processing of foods. Further, their capabilities for better design and operation of these processes will be highlighted with selected case studies, where the generated Pareto solutions will be analysed. Finally, we will also illustrate their advantages over other recently proposed strategies.     

Applied and Emerging Methods for Meat Tenderization: A Comparative Perspective

The tenderization process, which can be influenced by both pre‐ and post‐slaughter interventions, begins immediately after an animal's death and is followed with the disruption of the muscle structure by endogenous proteolytic systems. The post‐slaughter technological interventions like electrical stimulation, suspension methods, blade tenderization, tumbling, use of exogenous enzymes, and traditional aging are some of the methods currently employed by the meat industry for improving tenderness. Over the time, technological advancement resulted in development of several novel methods, for maximizing the tenderness, which are being projected as quick, economical, nonthermal, green, and energy‐efficient technologies. Comparison of these advanced technological methods with the current applied industrial methods is necessary to understand the feasibility and benefits of the novel technology. This review discusses the benefits and advantages of different emerging tenderization techniques such as hydrodynamic‐pressure processing, high‐pressure processing, pulsed electric field, ultrasound, SmartStretch^?, Pi‐Vac Elasto‐Pack® system, and some of the current applied methods used in the meat industry.     

Techno-functional properties of dry-fractionated plant-based proteins and application in food product development: a review

Dry-fractionated protein concentrates are gaining attention because they are produced using a versatile and sustainable technology, which can be applied to a wide range of plant material. To facilitate their utilization in new product development, it is crucial to obtain a comprehensive overview of their techno-functional properties. The present review aims to examine the techno-functional properties of dry-fractionated protein concentrates and describe their primary applications in food products, considering the published works in the last decade. The techno-functional properties of proteins, including water absorption capacity, emulsifying and foaming properties, gelling ability or protein solubility, are relevant factors to consider during food formulation. However, these properties are significantly influenced by the extraction technology, the type of protein and its characteristics. Overall, dry-fractionated proteins are characterized by high protein solubility, high foaming ability and foam stability, and high gelling ability. Such properties have been exploited in the development of food, such as bakery products and pasta, with the aim of increasing the protein content and enhancing the nutritional value. Additionally, innovative foods with distinctive textural and nutritional characteristics, such as meat and dairy analogues, have been developed by using dry-fractionated proteins. The results indicate that the study of these ingredients still needs to be improved, including their application with a broader range of plant materials. Nevertheless, this review could represent an initial step to obtaining an overview of the techno-functional properties of dry-fractionated proteins, facilitating their use in foods. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.     

Identification and molecular docking study of novel cholesterol esterase inhibitory peptides from camel milk proteins

Novel bioactive peptides from camel milk protein hydrolysates (CMPH) were identified and tested for inhibition of cholesterol esterase (CEase), and their possible binding mechanisms were elucidated by molecular docking. Papain-generated CMPH showed the highest degree of hydrolysis. All CMPH produced upon enzymatic degradation demonstrated a dramatic enhancement of CEase inhibition compared with intact camel milk proteins, with papain-generated hydrolysate P₉ displaying the highest inhibition. Peptide identification and their modeling through PepSite 2 revealed that among 20 potential bioactive peptides in alcalase-generated hydrolysate A₉, only 3 peptides, with sequences KFQWGY, SQDWSFY, and YWYPPQ, showed the highest binding toward CEase catalytic sites. Among 43 peptides in 9-h papain-generated hydrolysate P₉, 4 peptides were found to be potent CEase inhibitors. Molecular docking revealed that WPMLQPKVM, CLSPLQMR, MYQQWKFL, and CLSPLQFR from P₉ hydrolysates were able to bind to the active site of CEase with good docking scores and molecular mechanics–generalized born surface area binding energies. Overall, this is the first study reporting CEase inhibitory potential of peptides generated from milk proteins.