Electron beam radiation of dried fruits and nuts to reduce yeast and mold bioburden

Dried fruits and nuts make up a significant portion of the commodities traded globally, and the presence of yeasts and molds on dried fruits and nuts can be a public health risk because of the potential for exposure to toxigenic fungi. Since current postharvest treatment technologies are rather limited for dried fruits and nuts, electron beam (E-beam) radiation experiments were performed to determine the doses required to reduce the yeast and mold bioburden of raisins, walnuts, and dates. The indigenous yeast and mold bioburden on a select number of commodities sold at retail ranged from 10(2) to 10(3) CFU/g. E-beam inactivation kinetics based on the linear model suggest that the decimal reduction dose required to eliminate 90% of the microbial population (D10-value) of these indigenous fungal populations ranges from 1.09 to 1.59 kGy. Some samples, however, exhibited inactivation kinetics that were better modeled by a quadratic model. The results indicate that different commodities can contain molds and yeasts of varying resistance to ionizing radiation. It is thus essential for the dried fruit and nut industry to determine empirically the minimum E-beam dose that is capable of reducing or eliminating the bioburden of yeasts and molds in their specific commodities.     

Radiation preservation of foods of plant origin. III. Tropical fruits: bananas, mangoes, and papayas

The current status of research on the use of ionizing radiation for shelf life improvement and disinfestation of fresh tropical fruits like bananas, mangoes, and papayas are reviewed. The aspects covered are influence of maturity and physiological state of the fruits on delayed ripening and tolerance to radiation; varietal responses; changes in chemical constituents, volatiles, respiration, and ethylene evolution; biochemical mechanisms of delayed ripening and browning of irradiated fruits; and organoleptic quality. The efficacy of the combination of hot water dip and radiation treatments for control of postharvest fungal diseases are considered. The immediate potential of radiation as a quarantine treatment, in place of the currently used chemical fumigants, for disinfestation of fruit flies and mango seed weevil are discussed. Future prospects for irradiation of tropical fruits are discussed in the light of experience gained from studies conducted in different countries.     

坚果和干果中黄曲霉毒素的污染、检测与控制

坚果和干果在生产、加工和储藏过程中易受到黄曲霉毒素污染。黄曲霉毒素是一类毒性极强的真菌毒素, 其中黄曲霉毒素B1污染最普遍、毒性最强, 其易引发急、慢性毒性, 致癌、致畸、免疫抑制等多种危害, 严重威胁果品安全, 危害人类健康。坚果和干果中黄曲霉毒素污染状况的阐释能够更加明晰其在不同果品中的污染差异, 为有针对性地控制毒素污染奠定了基础。坚果和干果中黄曲霉毒素的准确检测是分析其污染状况的前提。另外, 如何防控黄曲霉毒素在坚果和干果中的污染, 降低黄曲霉毒素对人类健康的影响, 一直是研究的重点。本文对国内外坚果和干果中黄曲霉毒素的污染情况及限量标准, 黄曲霉毒素的检测方法和防控措施进行了综述, 以期为坚果和干果中黄曲霉毒素的污染控制提供理论基础和指导。     

Recent advances in pressure modification-based preservation technologies applied to fresh fruits and vegetables

Fresh fruits and vegetables are important parts of the human diet. The consumer demand for fruits and vegetables is increasing due to their rich nutritional value, appealing taste, and healthy perception. However, due to their highly perishable nature, appropriate preservation technologies must be developed to meet the consumer’s demand for healthy, additive-free, microbiologically safe, and high quality fresh fruits and vegetables. The preservation technologies based on modification or control of pressure alters the normal atmospheric pressure of the preservation environment. The materials to be preserved are subjected to either very high or low pressure to extend their shelf life. The mechanism, advantages, and limitations of pressure modification-based preservation methods such as high hydrostatic pressure, hyperbaric treatment, vacuum cooling, hypobaric storage, and vacuum packaging focusing on their applicability to fresh fruits and vegetables have been reviewed. This review suggests that these technologies have potential to extend the shelf life and achieve a better preservation of the quality of fresh fruits and vegetables.     

Life history of Plodia interpunctella (Lepidoptera: Pyralidae) on dried fruits and nuts: Effects of macronutrients and secondary metabolites on immature stages

The objective of this study was to investigate the effects of nutrients and secondary metabolites content in 16 types of dried fruits and four nuts from Serbia on life history traits of Plodia interpunctella (Hübner, 1813) immature stages. The analysis of nutrients content included determination of the total moisture, ash, proteins, fats, carbohydrates, sugars, and total reducing sugars, while from secondary metabolites total phenolics, flavonoids and tannins contents were determined. Life history traits included the developmental duration of larvae (LDD), developmental duration of pupae (PDD) and total immature stages (MDD), as well as the survival of larvae and pupae. Additional analyses was conducted on time-specific survival, as well as on the age- and size-growth patterns of P. interpunctella larvae. The principal component analysis (PCA) indicated that the content of proteins and fats is in strong positive correlation with larval and total immature stages survival, while in negative correlation with LDD, PDD, and MDD. The content of secondary metabolites are in strong positive correlation with LDD and MDD, while in negative correlation with larval and total immature stages survival. Considering the fastest development and high number of survived larvae and pupae, the walnuts, hazelnuts and almonds were more suitable for the development of P. interpunctella than tested dried fruits in general, while the goji berries and figs were the most suitable among tested dried fruits. The results of the effects of tested dried fruits and nuts from Serbia on life history traits of P. interpunctella, combined with studies from different countiries using local varieties and cultivars of dried fruits and nuts, could provide the data for modeling the growth and population dynamics, important for forcasting and signaling the occurance of this pest.     

Recent advances in modified atmosphere packaging and edible coatings to maintain quality of fresh-cut fruits and vegetables

Processing of fruits and vegetables generates physiological stresses in the still living cut tissue, leading to quality deterioration and shorter shelf life as compared with fresh intact produces. Several strategies can be implemented with the aim to reduce the rate of deterioration of fresh-cut commodities. Such strategies include low temperature maintenance from harvest to retail and the application of physical and chemical treatments such as modified atmosphere packaging (MAP) with low O₂ and high CO₂ levels and antioxidant dips. Other technologies such as edible coatings with natural additives, new generation of coatings using nanotechnological solutions such as nanoparticles, nanoencapsulation, and multilayered systems, and nonconventional atmospheres such as the use of pressurized inert/noble gases and high levels of O₂ have gained a lot of interest as a possibility to extend the shelf life of minimally processed fruits and vegetables. However, the high perishability of these products challenges in many cases their marketability by not achieving sufficient shelf life to survive the distribution system, requiring the combination of treatments to assure safety and quality. This review reports the recent advances in the use of MAP, edible coatings, and the combined effect of both technologies to extend the shelf life of fresh-cut fruits and vegetables.     

Evaluating the in vitro bioaccessibility of phenolics and antioxidant activity during consumption of dried fruits with nuts

Dried fruits and nuts are considered as healthy snacks and they are often consumed together in the Turkish diet. In order to investigate the effect of codigestion of dried fruits (figs, apricots, raisins) together with nuts (almonds, walnuts, hazelnuts), total phenolics (TP) and total antioxidant capacity (TAC) have been evaluated spectrophotometrically at different phases of simulated gastrointestinal (GI) digestion, using an in vitro model. TP, ABTS and CUPRAC results revealed that for all fruit–nut mixtures, the amount recovered in the dialyzed fraction was lower than the recovery of fruits or nuts alone, indicating an antagonistic effect. On the other hand, DPPH results showed that for fig–walnut, fig–hazelnut and apricot–hazelnut mixtures the quantity recovered in the dialyzed fractions were 35–107% higher than the recovery of fruits or nuts alone, representing a synergistic effect. Similarly, FRAP results also demonstrated a synergistic effect in case of fig–walnut, apricot–walnut and apricot–hazelnut mixtures (10–74% higher recovery). Current study provides valuable insights into the changes taking place during in vitro GI digestion of dried fruits and nuts.     

Total antioxidant capacity of spices, dried fruits, nuts, pulses, cereals and sweets consumed in Italy assessed by three different in vitro assays

With the aim to expand the Italian total antioxidant capacity (TAC) database, the TAC values of 11 spices, 5 dried fruits, 7 sweets, 18 cereal products, 5 pulses, and 6 nuts were determined using three different assays and considering the contribution of bound antioxidant compounds in fiber-rich foods (i. e. cereals, legumes, and nuts). Among spices, saffron displayed the highest antioxidant capacity, whereas among dried fruits, prune exhibited the highest value. The TAC values of all the chocolates analyzed were far higher than the other sweet extracts measured. Among cereal products, whole meal buckwheat and wheat bran had the greatest TAC. Among pulses and nuts, broad bean, lentil and walnuts had the highest antioxidant capacity, whereas chickpeas, pine nuts and peanuts were less effective. The contribution of bound phytochemicals to the overall TAC was relevant in cereals as well as in nuts and pulses. The complete TAC database could be utilized to properly investigate the role of dietary antioxidants in disease prevention.     

Radiation preservation of foods of plant origin. Part V. Temperate fruits: pome fruits, stone fruits, and berries

The current status of research on the application of ionizing radiation for improving the storage of temperate fruits, i.e., apple, pear, peach, nectarine, apricot, cherry, plum, strawberry, bilberry, cranberry, raspberry, and black currant, is reviewed. Changes in fruit metabolism, chemical composition, texture, and organoleptic quality attributes are discussed with reference to the irradiation dose. The feasibility of using radiation either alone or in conjunction with heat treatment, refrigeration, and controlled atmospheres (CA) for the control of storage decay caused by fungal pathogens is considered. Areas of further research are suggested before irradiation could be considered for practical application in some of these temperate fruits. The recent trends in the possible use of irradiation for disinfestation of certain pome and stone fruits and the prospects for the commercial utilization of irradiation for improving the market life of strawberries are discussed.     

Worldwide Status of Fresh Fruits Irradiation and Concerns about Quality,Safety, and Consumer Acceptance

Development of knowledge-based food preservation techniques have been a major focus of researchers in providing safe and nutritious food. Food irradiation is one of the most thoroughly investigated food preservation techniques, which has been shown to be effective and safe through extensive research. This process involves exposing food to ionizing radiations in order to destroy microorganisms or insects that might be present on and/or in the food. In addition, the effects of irradiation on the enzymatic activity and improvement of functional properties in food have also been well established. In the present review, the potential of food irradiation technology to address major problems, such as short shelf life, high-initial microbial loads, insect pest management (quarantine treatment) in supply chain, and safe consumption of fresh fruits was described. With improved hygienic quality, other uses, such as delayed ripening and enhanced physical appearance by irradiation were also discussed. Available data showed that the irradiation of fruits at the optimum dose can be a safe and cost-effective method, resulting in enhanced shelf life and hygienic quality with the least amount of compromise on the various nutritional attributes, whereas the consumer acceptance of irradiated fruits is a matter of providing the proper scientific information.     

Mycotoxins in fruits,fruit juices,and dried fruits

This review gives an overview of the presence of mycotoxins in fruits. Although several mycotoxins occur in nature, very few (aflatoxins, ochratoxin A, patulin, Alternaria toxins) are regularly found in fruits. It has been shown that the presence of fungi on fruits is not necessarily associated with mycotoxin contamination. The formation of mycotoxins depends more on endogenous and environmental factors than fungal growth does. Mycotoxins may remain in fruits even when the fungal mycelium has been removed. Depending on the fruit and the mycotoxin, the diffusion of mycotoxins into the sound tissues of fruits may occur. The influence of the selection and storage of fruits and the influence of different processing steps involved in the production of fruit juices and dried fruits on possible mycotoxin contamination is described. It is shown that the careful selection, washing, and sorting of fruits is the most important factor in the reduction of mycotoxin contamination during the production of fruit juices. The processing of fruits does not result in the complete removal of mycotoxins.     

Quality properties of fruits as affected by drying operation

The increasing consumption of dried fruits requires further attention on the quality parameters. Drying has become necessary because most fruits are highly perishable owing to their high moisture content and the need to make them available all year round and at locations where they are not produced. In addition to preservation, the reduced weight and bulk of dehydrated products decreases packaging, handling and transportation costs. Quality changes associated with drying of fruit products include physical, sensory, nutritional, and microbiological. Drying gives rise to low or moderate glycemic index (GI) products with high calorie, vitamin and mineral contents. This review examines the nutritional benefits of dried fruits, protective compounds present in dried fruits, GI, overview of some fruit drying methods and effects of drying operations on the quality properties such as shrinkage, porosity, texture, color, rehydration, effective moisture diffusivity, nutritional, sensory, microbiological and shelf stability of fruits.     

Cold Plasma for Effective Fungal and Mycotoxin Control in Foods: Mechanisms,Inactivation Effects,and Applications

Cold plasma treatment is a promising intervention in food processing to boost product safety and extend the shelf‐life. The activated chemical species of cold plasma can act rapidly against micro‐organisms at ambient temperatures without leaving any known chemical residues. This review presents an overview of the action of cold plasma against molds and mycotoxins, the underlying mechanisms, and applications for ensuring food safety and quality. The cold plasma species act on multiple sites of a fungal cell resulting in loss of function and structure, and ultimately cell death. Likewise, the species cause chemical breakdown of mycotoxins through various pathways resulting in degradation products that are known to be less toxic. We argue that the preliminary reports from cold plasma research point at good potential of plasma for shelf‐life extension and quality retention of foods. Some of the notable food sectors which could benefit from antimycotic and antimycotoxin efficacy of cold plasma include, the fresh produce, food grains, nuts, spices, herbs, dried meat and fish industries.     

The microbial safety of strawberry and raspberry fruits packaged in high-oxygen and equilibrium-modified atmospheres compared to air storage

Microbial safety of strawberry and raspberry fruits was assessed after shelf‐life extension by two new packaging systems, high‐oxygen atmospheres (HOA) and equilibrium‐modified atmospheres (EMA), in combination with an ethylene absorbing film. Both fruits had a shelf‐life of 3 days at 7 °C when macroperforated films were used. Strawberry fruits were acceptable for 5 days in both packages, raspberries had a shelf‐life of 7 and 5 days when using EMA and HOA respectively. Escherichia coli, Salmonella spp. and Listeria monocytogenes were artificially inoculated onto packaged fruits. All were able to survive on packaged fruits stored at 7 °C. Raspberries showed an enhanced inactivation of Salmonella during storage time in both types of packaging. Growth of L. monocytogenes was observed on the calyx of strawberries after the end of the established shelf‐life. Generally, increasing the shelf‐life of the fruits with EMA and HOA did not give an increased microbial risk.     

Perceptions of the health and convenience characteristics of fresh and dried fruits

Dried fruits consumption has not received much research attention, although these foods are associated with potential health benefits. Therefore, the aim of this study was to compare fresh fruits and dried fruits on measures of health, convenience and consumer feelings.An on-line questionnaire that measured consumers' perceptions of the health benefits and convenience characteristics and their feelings about the consumption of both fresh fruits (apples and plums) and dried fruits (e.g., raisins, dates, and apricots) was completed by 693 respondents (Polish, French, and Dutch).Generally, fresh fruits were perceived to be healthier and less convenient than dried fruits. Consumers also reported more positive feelings about the consumption of fresh fruits compared to dried fruits. The more that the respondents were willing to sacrifice for their health, the more positively they rated the health aspects of both fresh and dried fruits, as well as several perceptions of convenience of both fresh and dried fruits. Health preoccupation was unrelated to most of the convenience perceptions and was associated with lower scores on several perceptions of healthiness. Recommendations for the consumer-oriented development of dried fruits are also provided.     

干燥方式对复水香菇感官、质构及营养品质的影响

为获得复水性较好的干香菇,研究了热风干燥（hot-air drying,HAD）、中短波红外干燥（infrared radiation drying,IRD）和真空冷冻干燥（freeze drying,FD）香菇的复水特性及复水后的综合品质。结果表明：FD香菇具有均匀的多孔结构,使得干香菇的复水速率明显高于HAD香菇和IRD香菇,复水60?min即可达最大复水体积比（9.22）,且复水香菇的外观与鲜样接近。同时,复水后FD香菇的剪切力（1?352.99?g）和咀嚼性（232.54?g）最小,表明其质地柔软、易被切分。此外,FD复水香菇和其他两种复水香菇具有相似的电子鼻响应值曲线,表明其香气无差异。复水时FD香菇的蛋白质和VB2的溶出率最高,分别为0.42?mg/g和0.71×10－3?mg/g,说明FD复水香菇富含营养成分,且加工时较易溶出。综上,FD可作为一种较好的干燥方式来制备复水性较好的高品质香菇。     

Radiation processing to improve the quality of fishery products.

Extensive investigations, worldwide, in the last 4 decades have shown the benefits of radiation processing for the preservation and microbial quality improvement of seafoods. In the present review, the various factors determining the quality of seafoods are first presented. The basic principles underlying the effects of ionizing radiation and specific effects on food constituents such as proteins, amino acids, lipids, vitamins, and tissue enzymes are discussed. Data on radiation processing of seafoods are reported and discussed with respect to shelf life enhancement under refrigeration by control of bacteria causing spoilage, radiation sensitivity of pathogenic microorganisms and parasites of public health significance and their elimination in fresh and frozen fishery products, control of insect disinfestation in dried fishery products, influence of irradiation on nutritional and sensory quality attributes, detection of irradiation treatment, economics, and international status.     

臭氧在果蔬保鲜和农残降解上的应用

臭氧是一种强氧化剂，它可以杀灭果蔬上的微生物，去除果蔬释放的乙烯，抑制果蔬的呼吸作用，延长果蔬的保鲜期。臭氧还可以降解果蔬上的农药残留。尽管可能会对某些果蔬的品质造成损伤，但具有高活性、高渗透性和无毒降解产物的特点的臭氧在果蔬采后处理上有着巨大的应用潜力。     

1-甲基环丙烯在抑制果实衰老软化方面的应用

1-甲基环丙烯是一种乙烯作用抑制剂,可以延缓果实采后衰老与软化,提高果实的贮藏品质和货架寿命。概括了1-甲基环丙烯抑制果实衰老软化的作用效果及常见果品1-MCP处理的最佳温度、时间,展望了1-MCP在果实贮藏保鲜上的应用现状及前景。     

基于不同方法评价坚果与果干复配物的抗氧化能力

为科学评价坚果与果干复配物的健康功效,本实验通过化学提取法、体外消化模型、小鼠模型评价多种坚果与果干复配后的抗氧化能力变化。化学提取法分析结果表明,坚果与果干复配后富含酚类物质、脂肪酸和蛋白等营养物质,且1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picrylhydrazyl,DPPH）自由基清除能力、2,2-联氨-双-3-乙基苯并噻唑啉-6-磺酸（2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic?acid),ABTS）阳离子自由基清除能力和铁离子还原能力（ferric?ion?reducing?antioxidant?power,FRAP）比坚果组总体显著提高（P<0.05）;体外消化模型分析结果表明,与坚果和果干组相比,胃肠道消化后坚果与果干复配物中酚类物质的含量提高了2.90%～60.38%,两种自由基清除率提高了1.23%～18.60%,且坚果与果干适当配比时（6∶4,m/m）抗氧化协同效果最好;小鼠模型实验分析结果表明坚果与果干复配物在体内消化后提高了小鼠血清和肝脏中过氧化氢酶、超氧化物歧化酶活力及总抗氧...