Food Waste Management and Value-added Products

ABSTRACT: Optimization of thermal treatments has been proven to enhance the quality of food products, especially when operated together with a validation method that confirms the safety of the processing operations. Recent developments in the understanding and application of pasteurization treatments have allowed this area to grow at a rapid rate. UK and European consumers now have a wide variety of high-quality pasteurized foods to choose from in the retail and catering markets. Food producers have used this to their advantage by converting processing operations from severe treatments such as sterilization to milder ones that can be categorized under the pasteurization umbrella. This has increased food product quality and added value to existing products. Two examples will be given, both of which utilized a novel validation method based on time-temperature integrators to provide process safety data that were difficult to obtain by alternative methods. The first was in applying a novel processing technology, ohmic heating, to produce higher-quality fruit products when compared with traditional processing methods. The second was in the production of high-quality sous vide ready meals supplied chilled or frozen to the catering sector. These developments in technology and validation have been made possible by work at CCFRA that has taken the pasteurized foods sector forward. CCFRA has been active in pasteurization research for many years and has produced industry guideline documents on, for example, pasteurization treatments and sous vide processing. Microbiological research on the growth and death of target microorganisms has been linked with processing, hygiene, and validation research, which provided the underpinning science for these guidelines. Food manufacturers work closely with CCFRA to apply their pasteurization processes in order to produce high-quality value-added products.     

Thermal pasteurization requirements for the inactivation of Salmonella in foods

Thermal processing is still one of the most effective methods for inactivating undesirable microorganisms in foods. Heat is used to inactivate pathogens and in developing typical flavours, aromas, texture and colour of a cooked food. Pasteurization produces safer foods with longer shelf-life. Since mild temperatures are applied for a specified time, complementary food preservation techniques such as modified atmospheres, addition of preservatives or the use of refrigerated storage and distribution, might be needed to control the growth of the surviving microorganisms. This review starts by addressing food contamination by Salmonella spp., referring to some examples of outbreaks, and the benefits of pasteurization in terms of Salmonella inactivation. A section covering the thermal resistance studies of Salmonella in poultry and other animal-based foods is presented. Based on Salmonella thermal resistance data, minimum pasteurization times are suggested at different heating temperatures, to meet the guidelines and recommendations of governmental food agencies for meat products (7 log reduction). Validation of a minimum pasteurization time must be done for each specific food-thermal process, by inserting a thermocouple into the “coldest” spot of the food , and ensuring that this point is submitted to the minimum pasteurization value required. This procedure will guarantee food safety with respect to Salmonella. Salmonella pasteurization requirements of low moisture foods such as some nuts, chocolate and peanut butter are also reviewed.     

Technologies and Mechanisms for Safety Control of Ready-to-eat Muscle Foods: An Updated Review

Ready-to-eat (RTE) muscle foods refer to a general category of meat and poultry products that are fully cooked and consumable without reheating. These products, including whole and sliced pork, beef, turkey, chicken, and variety of meats, in the forms of ham, roast, rolls, sausage, and frankfurter, are widely available in the delicatessen section of retail stores or various food service outlets. However, difficulties in avoidance of contamination by foodborne pathogens, notably Listeria monocytogenes, during product postlethality repackaging render RTE meats labile to outbreaks. Accordingly, the USDA-FSIS has established processing guidelines and regulations, which are constantly updated, to minimize foodborne pathogens in RTE products. Technologies that complement good manufacturing practice have been developed to control RTE meat safety. Among them, various antimicrobial product formulations, postpackaging pasteurization (thermal and nonthermal), and antimicrobial packaging are being used. Through these efforts, outbreaks linked to RTE meat consumption have substantially reduced in recent years. However, the pervasive and virulent nature of L. monocytogenes and the possible presence of other cold-tolerant pathogens entail continuing developments of new intervention technologies. This review updates existing and emerging physical and chemical methods and their mode of action to inactivate or inhibit threatening microorganisms in RTE muscle foods.     

Nonthermal Food Processing Alternatives and Their Effects on Taste and Flavor Compounds of Beverages

Food drinks are normally processed to increase their shelf-life and facilitate distribution before consumption. Thermal pasteurization is quite efficient in preventing microbial spoilage of many types of beverages, but the applied heat may also cause undesirable biochemical and nutritious changes that may affect sensory attributes of the final product. Alternative methods of pasteurization that do not include direct heat have been investigated in order to obtain products safe for consumption, but with sensory attributes maintained as unchanged as possible. Food scientists interested in nonthermal food preservation technologies have claimed that such methods of preserving foods are equally efficient in microbial inactivation as compared with conventional thermal means of food processing. Researchers in the nonthermal food preservation area also affirm that alternative preservation technologies will not affect, as much as thermal processes, nutritional and sensory attributes of processed foods. This article reviews research in nonthermal food preservation, focusing on effects of processing of food drinks such as fruit juices and dairy products. Analytical techniques used to identify volatile flavor-aroma compounds will be reviewed and comparative effects for both thermal and nonthermal preservation technologies will be discussed.     

代谢组学在食品质量安全领域的应用进展

食品质量安全是保障现代经济社会和谐稳定发展的基础与前提，目前，食源性致病微生物、兽药残留、转基因食品及掺假等问题均会造成或可能造成食品安全隐患。代谢组学作为新兴技术不断发展，通过研究生物体受外界干扰前后小分子代谢产物的变化，进而探究机体内代谢机制，适用于食品安全多种微量危害因子的鉴别和监测。此外，危害因子在食品分解过程中产生的代谢物可成为特定的潜在生物标志物，为致病菌作用机制和品质安全控制的研究提供参考。本文阐述靶向代谢组学和非靶向代谢组学，介绍代谢组学技术常用的数据采集和数理统计方法，总结代谢组学技术在食源性致病菌、兽药残留、转基因食品、生鲜食品品质和肉制品掺假等食品品质和安全领域的研究进展，并对多组学联用技术提出展望，以期推动该技术在食品质量安全领域更广泛的应用。     

Recent Advances in Food Processing Using High Hydrostatic Pressure Technology

High hydrostatic pressure is an emerging non-thermal technology that can achieve the same standards of food safety as those of heat pasteurization and meet consumer requirements for fresher tasting, minimally processed foods. Applying high-pressure processing can inactivate pathogenic and spoilage microorganisms and enzymes, as well as modify structures with little or no effects on the nutritional and sensory quality of foods. The U.S. Food and Drug Administration (FDA) and the U.S. Department of Agriculture (USDA) have approved the use of high-pressure processing (HPP), which is a reliable technological alternative to conventional heat pasteurization in food-processing procedures. This paper presents the current applications of HPP in processing fruits, vegetables, meats, seafood, dairy, and egg products; such applications include the combination of pressure and biopreservation to generate specific characteristics in certain products. In addition, this paper describes recent findings on the microbiological, chemical, and molecular aspects of HPP technology used in commercial and research applications.     

Validation of process technologies for enhancing the safety of low-moisture foods: A review

The outbreaks linked to foodborne illnesses in low-moisture foods are frequently reported due to the occurrence of pathogenic microorganisms such as Salmonella Spp. Bacillus cereus, Clostridium spp., Cronobacter sakazakii, Escherichia coli, and Staphylococcus aureus. The ability of the pathogens to withstand the dry conditions and to develop resistance to heat is regarded as the major concern for the food industry dealing with low-moisture foods. In this regard, the present review is aimed to discuss the importance and the use of novel thermal and nonthermal technologies such as radiofrequency, steam pasteurization, plasma, and gaseous technologies for decontamination of foodborne pathogens in low-moisture foods and their microbial inactivation mechanisms. The review also summarizes the various sources of contamination and the factors influencing the survival and thermal resistance of pathogenic microorganisms in low-moisture foods. The literature survey indicated that the nonthermal techniques such as CO₂, high-pressure processing, and so on, may not offer effective microbial inactivation in low-moisture foods due to their insufficient moisture content. On the other hand, gases can penetrate deep inside the commodities and pores due to their higher diffusion properties and are regarded to have an advantage over thermal and other nonthermal processes. Further research is required to evaluate newer intervention strategies and combination treatments to enhance the microbial inactivation in low-moisture foods without significantly altering their organoleptic and nutritional quality.     

Food Quality Evaluation using Model Foods: a Comparison Study between Microwave-Assisted and Conventional Thermal Pasteurization Processes

Thermal process optimization has focused on traditional sterilization, with limited research on pasteurization or microwave-assisted thermal processing. Model foods have been developed as quality evaluation tools for thermal pasteurization processes, but there are no comprehensive studies demonstrating how these model foods could be used to evaluate and compare the resulting food quality after different pasteurization processes. The aim of this study was to develop a methodology using image and quantitative analyses for quality evaluation of pre-packaged food pasteurized using a microwave-assisted pasteurization system (MAPS) and traditional hot water method. Four pasteurization processes (MAPS and hot water method at 90 and 95 °C) were designed to have an equivalent accumulated thermal lethality at the cold spot of at least 90 °C for 10 min to control nonproteolytic Clostridium botulinum spores. Color-based time-temperature indicators in mashed potato and green pea model foods were quantified using image analysis. Results showed that median color values were useful in assessing overall color change, and interquartile range was an indicator of burnt areas. MAPS 95 °C was the best process because it had the smallest hot spot cook values and the least color change, while the 90 °C hot water process was the worst. Model foods and image analysis techniques were useful pasteurization process quality evaluation tools and made it possible to visualize the potential food quality change volumetrically, throughout a food package. In the future, these tools could be combined with computer simulations to optimize the quality of pilot-scale and industrial MAPS or conventional pasteurization processes.     

真空-蒸汽-真空食品表面杀菌技术

食品安全质量一直是人们高度关注的焦点,畜禽肉、水果和蔬菜等固体食品的表面在生产过程中极易受到致病菌的污染,导致食物中毒和产品召回事件,对食品产业造成严重影响。真空-蒸汽-真空(vacuum-steam-vacuum,VSV)表面杀菌技术使食品交替暴露于真空和蒸汽环境,不但可以有效杀死致病菌,而且不会对食品品质造成不良影响。本文主要介绍了VSV杀菌技术的原理、设备构造和实际应用,并指出该技术今后一段时期内的研究重点。     

The challenges for global harmonisation of food safety norms and regulations: issues for India

Safe and adequate food is a human right, safety being a prime quality attribute without which food is unfit for consumption. Food safety regulations are framed to exercise control over all types of food produced, processed and sold so that the customer is assured that the food consumed will not cause any harm. From the Indian perspective, global harmonisation of food regulations is needed to improve food and nutrition security, the food trade and delivery of safe ready‐to‐eat (RTE) foods at all places and at all times. The Millennium Development Goals (MDGs) put forward to transform developing societies incorporate many food safety issues. The success of the MDGs, including that of poverty reduction, will in part depend on an effective reduction of food‐borne diseases, particularly among the vulnerable group, which includes women and children. Food‐ and water‐borne illnesses can be a serious health hazard, being responsible for high incidences of morbidity and mortality across all age groups of people. Global harmonisation of food regulations would assist in facilitating food trade within and outside India through better compliance, ensuring the safety of RTE catered foods, as well as addressing issues related to the environment. At the same time, regulations need to be optimum, as overregulation may have undue negative effects on the food trade. © 2013 Society of Chemical Industry     

Advances in Ultraviolet Light Technology for Non-thermal Processing of Liquid Foods

A negative, public reaction is growing over the addition of chemical preservatives to liquid foods and beverages to extend their shelf life and to protect against foodborne pathogens. As a physical method, ultraviolet light (UV) irradiation has a positive consumer image and is of interest to the food industry as a low cost non-thermal method of preservation. Recent advances in the science and engineering of UV light irradiation have demonstrated that this technology holds considerable promise as an alternative to traditional thermal pasteurization for liquid foods and ingredients, fresh juices, soft drinks, and beverages. However, its use for treating foods is still limited due to low UV transmittance of liquid foods. The goal of this review is to provide a summary of the basic principles of UV light generation and propagation with emphasis on its applications for liquid food processing. The review includes information on critical product and process factors that affect UV light inactivation and consequently the delivery of a required scheduled process in liquids foods; measuring and modeling of UV inactivation, and the important effects of UV light on overall quality and nutritional value of liquid foods. The commercially available UV light sources and UV reactor designs that were used for liquid foods treatment are reviewed. The research priorities and challenges that need to be addressed for the successful development of UV technology for liquid foods treatment are discussed.     

Reaction Kinetics at High Pressure and Temperature: Effects on Milk Flavor Volatiles and on Chemical Compounds with Nutritional and Safety Importance in Several Foods

Consumers demand, in addition to excellent eating quality, high standards of safety and nutrition in ready-to-eat food. This requires a continuous improvement in conventional processing technologies and the development of new alternatives. Prevailing technologies such as thermal processing can cause extensive and undesirable chemical changes in food composition while minimal processing strategies cannot eliminate all microbial pathogens. This review focuses on pressure-assisted thermal processing, a new alternative for shelf-stable foods. Its implementation requires an analysis of reaction kinetics at high pressure and elevated temperature. Acceleration of the inactivation of bacterial spores by the synergistic effect of pressure and temperature is expected to allow processing at lower temperature, shorter process time, or a combination of both. Therefore, thermal degradation of quality is expected to be lower than that of conventional thermal processes. However, few studies have focused on the effect of the conditions required for the inactivation of bacterial spores on the kinetics of chemical reactions degrading food quality, particularly at the high temperatures required for the processing of low-acid foods.     

Green Pea and Garlic Puree Model Food Development for Thermal Pasteurization Process Quality Evaluation

Development and selection of model foods is a critical part of microwave thermal process development, simulation validation, and optimization. Previously developed model foods for pasteurization process evaluation utilized Maillard reaction products as the time–temperature integrators, which resulted in similar temperature sensitivity among the models. The aim of this research was to develop additional model foods based on different time–temperature integrators, determine their dielectric properties and color change kinetics, and validate the optimal model food in hot water and microwave‐assisted pasteurization processes. Color, quantified using a^* value, was selected as the time–temperature indicator for green pea and garlic puree model foods. Results showed 915 MHz microwaves had a greater penetration depth into the green pea model food than the garlic. a^* value reaction rates for the green pea model were approximately 4 times slower than in the garlic model food; slower reaction rates were preferred for the application of model food in this study, that is quality evaluation for a target process of 90 °C for 10 min at the cold spot. Pasteurization validation used the green pea model food and results showed that there were quantifiable differences between the color of the unheated control, hot water pasteurization, and microwave‐assisted thermal pasteurization system. Both model foods developed in this research could be utilized for quality assessment and optimization of various thermal pasteurization processes.     

Promises and problems of functional foods

"Functional" foods are branded foods, which claim, explicitly or implicitly, to improve health or well being. We review typical functional foods and their ingredients, efficacy, and safety. We also review regulations for health claims for foods worldwide. These regulations often allow manufacturers to imply that a food promotes health without providing proper scientific evidence. At the same time, regulations may ban claims that a food prevents disease, even when it does. We offer a plea for regulations that will permit all health claims that are supported by the totality of scientific evidence, and ban all claims that suggest an unproven benefit.     

Recent developments in applications of radio frequency heating for improving safety and quality of food grains and their products: A review

Abstract

Food grains constitute a vital part of the daily diet of the population worldwide, and are generally considered as safe products with high storage stability due to their low moisture contents. However, post-harvest losses (PHL) caused by insects, fungi, food-borne pathogens, and undesirable enzymes remain a major concern for the grain industry. Thermal treatments are commonly used to reduce the PHL of grains and their products without any chemical residues. Among which, radio frequency (RF) technology has been regarded as a promising alternative to traditional heating methods for improving safety and quality of food grains due to its fast, volumetric, and deep penetration heating characteristics. This review provided comprehensive information about principles of RF technology and its main applications including disinfestation, pasteurization, enzyme inactivation, drying, and roasting for processing food grains and their products. The methods to improve the RF heating uniformity and effects of RF heating on product quality were also reviewed. Finally, the current problems and recommendations for future work related to RF processing of grains and their products were discussed. This review would improve the understanding of RF heating for food grains and their products and promote the application of RF technology in the food grain industry.     

Microbiology of Fresh Produce: Route of Contamination,Detection Methods,and Remedy

Fresh fruits and vegetables are an important part of a healthful diet. They provide vitamins, minerals and fiber to help keep our body healthy. Occasionally, fresh fruits and vegetables can become contaminated with harmful bacteria or viruses, which are also known as pathogens. The major family of pathogen associated with food are members of Enterobacteriaceae which commonly form a part of microbiological criteria and their presence is traditionally related to hygiene and safety of foods. Organic fertilizers, irrigation water quality and soil are major source of contamination. For removal of pathogens, various decontamination procedures are also followed to reduce microbial load on the fruits. These are chemical preservatives and irradiation. Microbiological study of fresh produce can be done by various phenotypic, biochemical and molecular techniques so that pathogen can properly be identified. The World Health Organization (WHO) developed global risk communication message and training materials to assist countries in strengthening their food educating programs. There is a need for improved surveillance systems on food-borne pathogens, on food products and on outbreaks so that comparable data are available from a wider range of countries.     

Using Photocatalyst Metal Oxides as Antimicrobial Surface Coatings to Ensure Food Safety—Opportunities and Challenges

Cross‐contamination of foods with pathogenic microorganisms such as bacteria, viruses, and parasites may occur at any point in the farm to fork continuum. Food contact and nonfood contact surfaces are the most frequent source of microbial cross‐contamination. In the wake of new and emerging food safety challenges, including antibiotic‐resistant human pathogens, conventional sanitation and disinfection practices may not be sufficient to ensure safe food processing, proper preparation, and also not be environmentally friendly. Nanotechnology‐enabled novel food safety interventions have a great potential to mitigate the risk of microbial cross‐contamination in the food chain. Especially engineered nanoparticles (ENPs) are increasingly finding novel applications as antimicrobial agents. Among various ENPs, photocatalyst metal oxides have shown great promise as effective nontargeted disinfectants over a wide range of microorganisms. The present review provides an overview of antimicrobial properties of various photocatalyst metal oxides and their potential applications as surface coatings. Further, this review discusses the most common approaches to developing antimicrobial coatings, methods to characterize, test, and evaluate antimicrobial efficacy as well as the physical stability of the coatings. Finally, regulations and challenges concerning the use of these novel photocatalytic antimicrobial coatings are also discussed.     

Advanced applications of chemo-responsive dyes based odor imaging technology for fast sensing food quality and safety: A review

Public attention to foodquality and safety has been increased significantly. Therefore, appropriate analytical tools are needed to analyze and sense the food quality and safety. Volatile organic compounds (VOCs) are important indicators for the quality and safety of food products. Odor imaging technology based on chemo-responsive dyes is one of the most promising methods for analysis of food products. This article reviews the sensing and imaging fundamentals of odor imaging technology based on chemo-responsive dyes. The aim is to give detailed outlines about the theory and principles of using odor imaging technology for VOCs detection, and to focus primarily on its applications in the field of quality and safety evaluation of food products, as well as its future applicability in modern food industries and research. The literatures presented in this review clearly demonstrated that imaging technology based on chemo-responsive dyes has the exciting effect to inspect such as quality assessment of cereal , wine and vinegar flavored foods , poultry meat, aquatic products, fruits and vegetables, and tea. It has the potential for the rapid, reliable, and inline assessment of food safety and quality by providing odor-image-basedmonitoring tool. Practical Application : The literatures presented in this review clearly demonstrated that imaging technology based on chemo-responsive dyes has the exciting effect to inspect such as quality assessment of cereal , wine and vinegar flavored foods, poultry meat, aquatic products, fruits and vegetables, and tea.     

The Impact of Cooling Rate on the Safety of Food Products as Affected by Food Containers

In recent decades, the demand for ready‐to‐eat (RTE) food items prepared by the food catering sector has increased together with the value of cook‐serve, cook‐chill, and cook‐freeze food products. The technologies by which foods are cooked, chilled, refrigerated for storage, and reheated before serving are of prime importance to maintain safety. Packaging materials and food containers play an important role in influencing the cooling rate of RTE foods. Food items that are prepared using improper technologies and inappropriate packaging materials may be contaminated with foodborne pathogens. Numerous research studies have shown the impact of deficient cooling technologies on the survival and growth of foodborne pathogens, which may subsequently pose a threat to public health. The operating temperatures and cooling rates of the cooling techniques applied must be appropriate to inhibit the growth of pathogens. Food items must be stored outside the temperature danger zone, which is between 5 and 60 °C, in order to inhibit the growth of these pathogens. The cooling techniques used to prepare potentially hazardous foods, such as cooked meat, rice, and pasta, must be properly applied and controlled to ensure food safety. This paper critically reviews the effects of cooling and its relationship to food containers on the safety of RTE foods produced and sold through the food service industry.     

食品胶体研究进展与未来趋势：组分互作、未来食品结构设计及胶体营养学视角

食品胶体一般指食品中的蛋白质、脂质、碳水化合物及其自组装所形成的多尺度微纳米构造。食品胶体作为食品结构的骨架基础,承载着食品的质构、风味、口感、稳定性、营养及健康特性,是维持食品品质的重要组成部分。本文将从食品胶体与食品组分互作、食品胶体与未来食品结构设计、食品胶体与细胞互作（胶体营养学）、食品胶体的体内代谢与安全性等方面,总结近年来食品胶体相关最新研究进展,展望食品胶体未来发展趋势,以期促进该领域朝前沿方向的快速发展。