REDUCTION IN MICROBIAL GROWTH AND IMPROVEMENT OF STORAGE QUALITY IN FRESH-CUT PINEAPPLE AFTER METHYL JASMONATE TREATMENT

Maintaining the quality of a fresh‐cut fruit or vegetable product is a major concern and a priority in the development and in the production of fresh‐cut produce products of the industry. The industry has been searching for alternative methods to protect fresh‐cut produce from decay and to prolong shelf life. The objective of this research is to enhance the quality and the shelf life of fresh‐cut pineapple by exposure to methyl jasmonate (MJ). The exposure of the diced pineapple to a MJ emulsion at a concentration of 10 ^?4 M for 5 min in a sealed container decreased microbiological growth by 3 logs after 12 days of storage at 7C, compared with the control pineapple. Methyl jasmonate as vapor or as dip did not affect the firmness or the color of the fruit. Methyl jasmonate may be a practical treatment to ensure the safety and the quality of fresh‐cut pineapple and other fruits and vegetables.     

Flavor quality of fruits and vegetables

Fruits and vegetables are important sources of vitamins, minerals, dietary fiber, and antioxidants. The relative contribution of each commodity to human health and wellness depends upon its nutritive value and per capita consumption; the latter is greatly influenced by consumer preferences and degree of satisfaction from eating the fruit or vegetable. Flavor quality of fruits and vegetables is influenced by genetic, preharvest, harvesting, and postharvest factors. The longer the time between harvest and eating, the greater the losses of characteristic flavor (taste and aroma) and the development of off‐flavors in most fruits and vegetables. Postharvest life based on flavor and nutritional quality is shorter than that based on appearance and textural quality. Thus, it is essential that good flavor quality be emphasized in the future by selecting the best‐tasting genotypes to produce, by using an integrated crop management system and harvesting at the maturity or ripeness stage that will optimize eating quality at the time of consumption, and by using the postharvest handling procedures that will maintain optimal flavor and nutritional quality of fruits and vegetables between harvest and consumption. Copyright © 2008 Society of Chemical Industry     

Modified Atmosphere Packaging of Pomegranate Fruit and Arils: A Review

Ongoing global drive for a healthier diet has led to a rise in demand for convenient and fresh food produce, with high nutritional value and free of additives. Minimally fresh processed fruits and vegetables, satisfies the consumers’ perception of a high nutritional quality and convenience produce. Minimally processed fruit and vegetables are susceptible to increased deterioration in quality and microbial infestation due to increase in endogenous enzymatic processes and respiration rate. Modified atmosphere packaging (MAP) technology offers the possibility to retard produce respiration rate and extend the shelf life of fresh produce. However, it is important to correlate the permeability properties of the packing films with the respiration rate of the produce, in order to avoid anaerobic conditions which could lead into fermentation of produce and accumulation of ethanol. Hence, mathematical prediction modelling is now widely applied in the design and development of effective MAP technology in both whole and minimally processed fresh produce. With increasing global interest in postharvest handling and nutrition value of pomegranate, MAP of minimally processed pomegranate arils offers additional innovative tool for optimal use and value addition, including the utilization of lower-grade fruit with superficial peel defects such as; cracks, splits, and sunburnt. This review paper highlights the current status and applications of modified atmosphere packaging in whole fruit and minimally processed pomegranate arils and identifies future prospects.     

Sweet cherry: Composition,postharvest preservation,processing and trends for its future use

BackgroundSweet cherries (Prunus avium L.) are a nutritious fruit which are rich in polyphenols and have high antioxidant potential. Most sweet cherries are consumed fresh and a small proportion of the total sweet cherries production is value added to make processed food products. Sweet cherries are highly perishable fruit with a short harvest season, therefore extensive preservation and processing methods have been developed for the extension of their shelf-life and distribution of their products.Scope and approachIn this review, the main physicochemical properties of sweet cherries, as well as bioactive components and their determination methods are described. The study emphasises the recent progress of postharvest technology, such as controlled/modified atmosphere storage, edible coatings, irradiation, and biological control agents, to maintain sweet cherries for the fresh market. Valorisations of second-grade sweet cherries, as well as trends for the diversification of cherry products for future studies are also discussed.Key findings and conclusionsSweet cherry fruit have a short harvest period and marketing window. The major loss in quality after harvest include moisture loss, softening, decay and stem browning. Without compromising their eating quality, the extension in fruit quality and shelf-life for sweet cherries is feasible by means of combination of good handling practice and applications of appropriate postharvest technology. With the drive of health-food sector, the potential of using second class cherries including cherry stems as a source of bioactive compound extraction is high, as cherry fruit is well-known for being rich in health-promoting components.     

Possibilities for the utilisation of marine by‐products

Fish industry by‐products can account for up to 75% of the catch depending on postharvest or industrial preparation processes. Different terms such as ‘fish waste’, ‘by‐product’ and ‘rest raw materials’ have been used. The review gives an overview of value‐added processes that provide an alternative to low‐profit uses such as silage, fish meal and mince. The preparation of different by‐product fractions such as fish blood, marine lipids, omega‐3 fatty acids, fish protein fractions and bioactive components with nutraceutical potential, i.e. antioxidants and bioactive peptides, is considered. There are several future opportunities for the preparation of high‐value by‐products such as enzymes, minerals and other bioactive substances including hydroxyapatite, phosphorus, taurine and creatine. Both regulatory status and future market potential need to be considered. In addition, there is a need for technologies that maintain good quality by‐products and ‘simple’ processes to produce bulk products for further refining.     

Current Scenario of Adsorbent Materials Used in Ethylene Scavenging Systems to Extend Fruit and Vegetable Postharvest Life

Fruit and vegetables are much appreciated by consumers due to their nutritional values and health-promoting compounds. However, different factors affect the postharvest life of such products, in where ethylene is a major one, even at low concentrations, besides temperature and relative humidity. Therefore, high attention has been focused on the development of effective tools to remove ethylene from the atmosphere surrounding these products during storage or in transit. Potassium permanganate scrubbers are one of the most used technologies to remove ethylene from horticultural products. To facilitate and improve the oxidation process, potassium permanganate has been supported onto inert solid materials of a small particle size. In this review, we aim to provide an outline of the most common materials used as potassium permanganate supports on postharvest treatment and their respective effects on quality aspects of various fresh produce during postharvest life. Vermiculite, activated alumina, zeolite, silica gel, activated carbon and clays are the most popular materials that have been used as a support of potassium permanganate-based ethylene scrubbers. The literature suggests that potassium permanganate supported onto silica gel or zeolite seems to be a promising tool to maintain fruit and vegetables quality attributes for long-term storage. Although vermiculite and activated alumina are the most commonly used materials to reach this goal, not promising results have been reported.     

Maintaining Antioxidant Potential of Fresh Fruits and Vegetables After Harvest

The consumption of fruits and vegetables has increased in the past few years, not only because of their attractive sensorial properties, but also for their nutritional and health benefits. Antioxidants are compounds found in fresh fruits and vegetables, and evidence of their role in the prevention of degenerative diseases is continuously emerging. However, the antioxidants in some fruits and vegetables can be lost during handling after harvest, even during minimal processing and storage. In this sense, postharvest treatments are needed to preserve the quality and antioxidant potential of fresh produce. Postharvest treatments and technologic strategies (including ultraviolet light, controlled and modified atmospheres, heat treatments, and application of natural compounds, such as edible coatings, active packaging, microencapsulation, and nanoemulsion) have shown positive and promising results to maintain fruit and vegetable antioxidant potential. The purpose of this review is to analyze and propose the application of postharvest strategies to maintain, or even improve, the antioxidant status of fruits and vegetables, thus offering options to maximize health benefits to consumers.     

Fresh‐Cut Onion: A Review on Processing,Health Benefits,and Shelf‐Life

The ready‐to‐eat produce market has grown rapidly because of the health benefits and convenience associated with these products. Onion is widely used as an ingredient in an extensive range of recipes from breakfast to dinner and in nearly every ethnic cuisine. However, cutting/chopping of onion is a nuisance to many consumers due to the lachrymatory properties of the volatiles generated that bring tears to eyes and leave a distinct odor on hands. As a result, there is now an increasing demand for fresh‐cut, value‐added, and ready‐to‐eat onion in households, as well as large‐scale uses in retail, food service, and various food industries, mainly due to the end‐use convenience. Despite these benefits, fresh‐cut onion products present considerable challenges due to tissue damage, resulting in chemical and physiological reactions that limit product shelf‐life. Intensive discoloration, microbial growth, softening, and off‐odor are the typical deteriorations that need to be controlled through the application of suitable preservation methods. This article reviews the literature related to the fresh‐cut onion, focusing on its constituents, nutritional and health benefits, production methods, quality changes throughout storage, and technologies available to increase product shelf‐life.     

Quality of fresh‐cut tomatoes as affected by salt content in irrigation water and post‐processing ultraviolet‐C treatment

BACKGROUND: There is little information available concerning the effect of sanitizing agents, including ultraviolet (UV‐C) light, on nutritional composition of fresh‐cut produce. In this study, the influence of UV‐C light irradiation (3.2–19.2 kJ m^?2) on the nutritional quality of fresh‐cut tomato cv. Durinta grown under either low (2.4/2.8 dS m^?1) or high (4.9/7.7 dS m^?1) electrical conductivity (EC) of the hydroponic nutrient influx/efflux solution was investigated. RESULTS: When grown under low EC UV‐C light treatment reduced development of microbial population of fresh‐cut tomato, increased phenolic content and delayed degradation of vitamin C after 7 days of storage at 4–6 °C. UV‐C light irradiation had no significant effect on appearance, color or lycopene content of fresh‐cut tomato. In recently harvested intact tomatoes, the lycopene and vitamin C contents were 30% higher in tomatoes irrigated with high EC, whereas the phenolic content was unaffected by the salt treatment. After fresh‐cut processing, phenolic and vitamin C contents of fresh cuts produced from tomatoes treated with high EC decreased by > 10%. This decline was initially accelerated in tomato treated with UV‐C light irradiation. CONCLUSIONS: Our results revealed that fresh‐cut tomatoes are affected dissimilarly by UV‐C treatments, depending on the degree of salt stress undergone by plants before harvest. We determined the impact of a sanitizing procedure on nutritional composition, an effect often overlooked but with great significance to ensure overall quality of fresh produce. Our findings revealed the need for more nutritional studies addressing the effect of multiple stress factors from pre‐harvest to post‐processing stages. Copyright © 2008 Society of Chemical Industry     

The Use of Controlled Postharvest Abiotic Stresses as a Tool for Enhancing the Nutraceutical Content and Adding-Value of Fresh Fruits and Vegetables

This paper proposes a concept based on applying postharvest abiotic stresses to enhance the nutraceutical content of fresh fruits and vegetables. We hypothesize that selected abiotic stress treatments, such as wounding, phytohormones, temperature, ultraviolet light, altered gas composition, heat shock, and water stress, among others, will affect the secondary metabolism of fresh produce and increase the synthesis of phytochemicals with nutraceutical activity or reduce the synthesis of undesirable compounds. Controlled stresses may be used as tools by the fresh produce industry to enhance the health benefit properties of fresh‐cut or whole fresh produce and by the food processing and dietary supplement industries to obtain healthier processed products or enhance extractable nutraceutical yields.     

Influence of Heat Treatments on Quality Retention of Fresh and Fresh-Cut Produce

Postharvest decay and insect infestation are two major causes that contribute towards higher postharvest losses during the fresh produce supply chain. Although decay and pest infestation could be controlled successfully via pesticide applications, the use of chemicals at the postharvest stage is becoming limited due to the strict regulations regarding pesticide residue levels enforced by importing countries. Heat treatments are environmentally friendly and recommended as alternative treatments to replace pesticide applications, especially with regard to fresh produce. These treatments help to eradicate pathogens or pests that are present on the fruit surface while maintaining the overall quality of the fresh produce during the supply chain. Browning is regarded as an economically important physiological disorder that causes detrimental effects on the quality maintenance of fresh-cut produce. Contamination of fresh produce by foodborne pathogens could occur at any stage during the production, harvesting, postharvest chain, or processing, and heat treatments could be recommended as an antibrowning or disinfection treatment for the fresh-cut industry. In light of the above, this review summarizes the effects of postharvest heat treatments on postharvest decay, insect infestation, physiological disorders, fruit ripening, retention of color, and bioactive compounds.     

Date fruit: chemical composition,nutritional and medicinal values,products

Date fruit has served as a staple food in the Arab world for centuries. Worldwide production of date fruit has increased almost threefold over the last 40 years, reaching 7.68 million tons in 2010. Date fruit can provide many essential nutrients and potential health benefits to the consumer. Date fruit goes through four ripening stages named kimri, khalal, rutab and tamer. The main chemical components of date fruit include carbohydrates, dietary fibre, enzymes, protein, fat, minerals, vitamins, phenolic acids and carotenoids. The chemical composition of date fruit varies according to ripening stage, cultivar, growing environment, postharvest conditions, etc. The nutritional and medicinal activities of date fruit are related to its chemical composition. Many studies have shown that date fruit has antioxidant, antimutagenic, anti‐inflammatory, gastroprotective, hepatoprotective, nephroprotective, anticancer and immunostimulant activities. Various date fruit‐based products such as date syrup, date paste, date juice and their derived products are available. Date by‐products can be used as raw materials for the production of value‐added products such as organic acids, exopolysaccharides, antibiotics, date‐flavoured probiotic‐fermented dairy produce, bakery yeasts, etc. In this paper the chemical composition and nutritional and medicinal values of date fruit as well as date fruit‐based products are reviewed . © 2013 Society of Chemical Industry     

The effects of ozonated water on the microbial counts and the shelf life attributes of fresh‐cut spinach

Fresh‐cut vegetables became more and more popular due to healthy eating habits, with main problem safety of the product because of microbial spoilage as well as visual and nutritional quality changes. Ozone may act as a sanitizer; however, due to its strong oxidant activity care is needed, as in some cases, that is, if the dose being used is too high, the quality of the produce may be reduced. In this study, ozonated water at various concentrations and dipping times (0, 0.4, 0.8, or 1.2 mg/L for 0, 1, 15, or 30 s) were tested. Results revealed that application of ozonated water (0.8 mg/L for 30 s) before packaging reduced yellowing and maintained compositional characteristics of the fresh‐cut spinach leaves, ensuring a shelf‐life extension of 3 days. Moreover, a positive effect on microbial population control was recorded during the first 5 days of storage.

Practical applications

The use of chlorine or other chemicals in fresh‐cut industry is decreasing while alternatives treatments are proposed. Ozone even had remarkable antimicrobial action however because of its oxidation action could be negative for the horticultural products. This work investigated the efficiency of ozone treatment (concentration and dipping time) to control yellowing of fresh‐cut spinach as well as the effect on microbial counts and leaves composition. The information obtained from this study provide the chance to extend the postharvest life of a highly perishable product with an alternative to chemical treatment that could be easily applied in processing line.     

Mechanical Models of Compression and Impact on Fresh Fruits

Well‐designed and well‐operated postharvest mechanical handling processes are vital if fresh fruits are to enter markets with minimal damage. The susceptibility of fruit to quality loss during handling is largely determined by mechanical contact and damage. This article reviews current understanding concerning the effect of impact and other mechanical contacts on fruits. It also discusses the major mechanical models that represent the interaction between fruits or a fruit and a surface. In total, 25 mechanical models associated with compression and impact behaviors of fresh fruits, mainly characterizing such behavior between 2 deformable spherical bodies and between a deformable spherical body and a rigid plate are reviewed. Finally, possible future research directions are discussed. The main challenge in fruit handling is to recognize and prevent microscopic damage to fruits, especially internal tissue/cell damage and microcracks resulting from multiple/repetitive impacts and compressions.     

Mandarin fruit quality: a review

During the last decade, there has been a continuous rise in consumption and global marketing of fresh, easy‐to‐peel mandarins, with current annual production of nearly 29 million tons. Nevertheless, most of the existing knowledge on quality traits of citrus fruit comes from research conducted on oranges and grapefruit, which are the main products for the citrus juice manufacturing industry; relatively little is yet known regarding the unique fruit quality traits of mandarins, nor about the great diversity in these traits among the various natural sub‐groups and varieties of mandarins. In the present review we discuss the physiological, biochemical, and molecular factors governing key fruit quality attributes of mandarins, including fruit colour, size and shape, ease of peeling, seedlessness, flavour, and nutritional quality. Fruit colour, size, and shape contribute to external appearance; peelability and seedlessness to ease of consumption; and flavour and nutritional quality to internal quality. © 2017 Society of Chemical Industry     

Electronic nose as a tool for early detection of diseases and quality monitoring in fresh postharvest produce: A comprehensive review

Postharvest diseases and quality degradation are the major factors causing food losses in the fresh produce supply chain. Hence, detecting diseases and quality deterioration at the asymptomatic stage of produce enables growers to treat the diseases earlier, maintain quality and reduce postharvest food losses. With the emergence of numerous technologies to detect diseases early and monitor the quality of fresh produce, such as polymerase chain reaction, gas chromatography-mass spectrophotometry, and near-infrared spectroscopy, electronic nose (EN) has also gained acknowledgement and popularity in the past decade as a robust and non-invasive analysis tool to detect odor profile and establish volatile biomarkers for metabolomics databases. However, literature reviewing the EN research on the early detection of diseases in produce after harvest is scarce. The fundamental concept of EN working principles (odor sampling, gas detection, and data acquisition method), as well as the application of EN as a whole, are covered in the first section of the review. An in-depth discussion of the application of EN analysis in the early identification of postharvest diseases and quality monitoring is provided in the subsequent sections, which is the key objective of this comprehensive review. The prospect, limitations, and likely future developments of EN in the postharvest sector are further highlighted in the last section.     

Colour Measurement and Analysis in Fresh and Processed Foods: A Review

Colour is an important quality attribute in the food and bioprocess industries, and it influences consumer’s choice and preferences. Food colour is governed by the chemical, biochemical, microbial and physical changes which occur during growth, maturation, postharvest handling and processing. Colour measurement of food products has been used as an indirect measure of other quality attributes such as flavour and contents of pigments because it is simpler, faster and correlates well with other physicochemical properties. This review discusses the techniques and procedures for the measurement and analysis of colour in food and other biomaterial materials. It focuses on the instrumental (objective) and visual (subjective) measurements for quantifying colour attributes and highlights the range of primary and derived objective colour indices used to characterise the maturity and quality of a wide range of food products and beverages. Different approaches applied to model food colour are described, including reaction mechanisms, response surface methodology and others based on probabilistic and non-isothermal kinetics. Colour is one of the most widely measured product quality attributes in postharvest handling and in the food processing research and industry. Apart from differences in instrumentation, colour measurements are often reported based on different colour indices even for the same product, making it difficult to compare results in the literature. There is a need for standardisation to improve the traceability and transferability of measurements. The correlation between colour and other sensory quality attributes is well established, but future prospects exist in the application of objective non-destructive colour measurement in predictive modelling of the nutritional quality of fresh and processed food products.     

Aqueous chlorine dioxide treatment of horticultural produce: Effects on microbial safety and produce quality–A review

Microbial load on fresh fruit and vegetables causes decay and losses after harvest and may lead to foodborne illness in case of contamination with human pathogens on raw consumed produces. Washing with tap water only marginally reduces microorganisms attached to produce surfaces. Chlorine is widely used for decontamination on fresh horticultural produces. However, due to harmful by-products and the questionable efficacy it has become increasingly challenged. During the last 20 years, the interest to study ClO₂ treatments as an alternative sanitation agent for industrially prepared fresh produce has largely increased. For a wide range of commodities, the application of gaseous ClO₂ has meanwhile been investigated. In addition, since several years, the interest in aqueous ClO₂ treatments has further risen because of the better manageability in postharvest processing lines compared to gaseous application. This article critically evaluated the effects of postharvest application of aqueous ClO₂, either alone or in combination with other treatments, on microbial loads for various horticultural produces. In laboratory investigations, application of aqueous ClO₂ at concentrations between 3 and 100 ppm effectively reduced counts of natural or inoculated microorganisms (bacteria, yeasts, and mold) in the range of 1 and 5 log. However, various effects of ClO₂ treatments on produce quality have been described. These mainly comprise implication on sensory and visual attributes. In this context, there is increasing focus on the potential impacts of aqueous ClO₂ on relevant nutritional components of produces such as organic acids or phenolic substances.     

龙眼果实品质劣变和贮藏保鲜技术研究进展

龙眼是中国南方重要的亚热带特色水果,其果实成熟于高温季节,采后极易发生果皮褐变、果肉自溶及病原菌侵染所致果实腐烂等品质劣变,是限制龙眼果实采后保鲜期的主要因素。本文就龙眼果实采后品质劣变(果皮褐变、果肉自溶、病原菌侵染导致果实变质腐烂),热处理、紫外线-强效应波长(UV-B)辐照处理、二氧化氯处理、壳聚糖处理、低温贮藏、气调冷藏、微生物生物保鲜等龙眼果实采后处理及保鲜技术的国内外研究进展进行综述,旨在为延缓采后龙眼果实品质劣变、延长龙眼果实保鲜期提供技术参考。     

A Systems Approach to the Evaluation of Changes in Quality During Postharvest Handling of Southern Peas

A systems approach was used to identify the step(s) which result in the greatest loss of quality during postharvest handling of southern peas. A maturity index was used to separate effects of handling and maturity on quality loss. In-field holding of the peas during truck loading is the most critical step in postharvest quality of southern peas. Attempts to control quality during transit from field to processing plant will be ineffective if proper control does not start during loading. Immature peas are more susceptible to loss of green color while more mature peas accumulate more lactic acid during handling. Use of a systems approach has ready applicability to the study of handling of fresh and processed fruit and vegetable products.