Cold plasma decontamination of brown rice grains: Impact on biochemical and sensory qualities of their corresponding seedlings and aqueous tea infusions

Effect of high hydrostatic pressure treatment on food composition and applications in food industry: A review

Nowadays, with the diversification of nutritious and healthy foods, consumers are increasingly seeking clean-labeled products. High hydrostatic pressure (HHP) as a cold sterilization technology can effectively sterilize and inactivate enzymes, which is conducive to the production of high-quality and safe food products with extended shelf life. This technology reduces the addition of food additives and contributes to environmental protection. Moreover, HHP enhances the content and bioavailability of nutrients, reduces the anti-nutritional factors and the risk of food allergen concerns. Therefore, HHP is widely used in the processing of fruit and vegetable juice drinks, alcoholic, meat products and aquatic products, etc. A better understanding of the influence of HHP on food composition and applications can guide the development of food industry and contribute to the development of non-thermally processed and environmentally friendly foods.

Application of cold argon plasma on germination, root length, and decontamination of soybean cultivars

Applying cold discharge plasma can potentially alter plants' germination characteristics by triggering their physiological activities. As a main crop in many countries, soybean was examined in the present study using cultivars such as Arian, Katoul, Saba, Sari, and Williams in a cold argon plasma. This study has been motivated by the importance of plant production worldwide, considering climate change and the increasing needs of human populations for food. This study was performed to inspect the effect of cold plasma treatment on seed germination and the impact of argon plasma on microbial decontamination was investigated on soybeans. Also, the employed cultivars have not been studied until now the radicals generated from argon were detected by optical emission spectrometry (OES), and a collisional radiative model was used to describe electron density. The germination properties, including final germination percentage (FGP), mean germination time (MGT), root length, and electrical conductivity of biomolecules released from the seeds, were investigated after the plasma treatments for 30, 60, 180, 300, and 420 s. The decontamination effect of the plasma on Aspergillus flavus (A.flavus) and Fusarium solani (F.solani) was also examined. The plasma for 60 s induced a maximum FGP change of 23.12 ± 0.34% and a lowest MGT value of 1.40 ± 0.007 days. Moreover, the ultimate root length was 56.12 ± 2.89%, in the seeds treated for 60 s. The plasma exposure, however, failed to yield a significant enhancement in electrical conductivity, even when the discharge duration was extended to 180 s or longer. Therefore, the plasma duration of 180 s was selected for the blotter technique. Both fungi showed successful sterilization; their infectivity inhibition was 67 ± 4 and 65 ± 3.1%, respectively. In general, the cold plasma used for soybeans in the present study preserved their healthy qualities and reduced the degree of fungal contamination.

Quality and antioxidant activity of dandelion root infusions as affected by cold plasma pretreatment

Ground and unground dandelion roots were subjected to dielectric barrier discharge cold plasma (DBDCP) at 40 kV for 0 (control), 10, or 20 min. Then, infusions of the pretreated dandelion roots in water were prepared, and the changes in color, total phenolic content (TPC), antioxidant activity, and sensory properties were investigated. The 20-min pretreatment increased the b* value, TPC, antioxidant activity, and sage odor of the ground dandelion root infusions compared with the control, whereas decreases in the TPC, antioxidant activity, and sage odor were noted in the 10-min pretreated infusions of the unground roots. DBDCP pretreatment did not affect the overall likeliness of infusions of ground and unground roots. In addition, the TPC, antioxidant activity, and overall likeliness of infusions of the ground dandelion roots were higher than those of the unground samples. In conclusion, it can be said that the DBDCP pretreatment can be utilized to improve the TPC and antioxidant activity of ground dandelion roots.

Recent developments in applications of physical fields for microbial decontamination and enhancing nutritional properties of germinated edible seeds and sprouts: a review

Germinated edible seeds and sprouts have attracted consumers because of their nutritional values and health benefits. To ensure the microbial safety of the seed and sprout, emerging processing methods involving physical fields (PFs), having the characteristics of high efficiency and environmental safety, are increasingly proposed as effective decontamination processing technologies. This review summarizes recent progress on the application of PFs to germinating edible seeds, including their impact on microbial decontamination and nutritional quality and the associated influencing mechanisms in germination. The effectiveness, application scope, and limitation of the various physical techniques, including ultrasound, microwave, radio frequency, infrared heating, irradiation, pulsed light, plasma, and high-pressure processing, are symmetrically reviewed. Good application potential for improving seed germination and sprout growth is also described for promoting the accumulation of bioactive compounds in sprouts, and subsequently enhancing the antioxidant capacity under favorable PFs processing conditions. Moreover, the challenges and future directions of PFs in the application to germinated edible seeds are finally proposed. This review also attempts to provide an in-depth understanding of the effects of PFs on microbial safety and changes in nutritional properties of germinating edible seeds and a theoretical reference for the future development of PFs in processing safe sprouted seeds.

Effects of degree of milling on nutritional quality, functional characteristics and volatile compounds of brown rice tea

This study investigated the effects of rice preparation using different degrees of milling (DOM) from 0% to 13% on the nutritional composition, functional properties, major volatile compounds and safety of brown rice tea (BRT). We found that 2% DOM reduced 52.33% of acrylamide and 31.88% of fluorescent AGEs. When DOM was increased from 0% to 13%, the total phenolic content (TPC) of brown rice tea decreased by 48.12%, and the total flavonoid content (TFC) and condensed tannin content (CTC) also decreased significantly, with the smallest decrease at 2% DOM. In addition, the inhibitory activities of α-amylase, α-glucosidase and pancreatic lipase as well as the antioxidant activity also decreased gradually. Analysis by electronic nose and gas chromatography-mass spectrometry (GC-MS) showed that alkanes, furans, aldehydes, pyrazines and alcohols were the major volatiles in BRT, with 2% DOM having the greatest retention of aroma compounds. An orthogonal partial least squares discriminant analysis (OPLS-DA) and VIP score (VIP > 1 and p < 0.05) analysis were used to screen 25 flavor substances that contributed to the differences in BRT aroma of different DOMs. These results suggest that 2% milled BRT can improve safety and palatability while maximizing the retention of flavor compounds and nutrients. The findings of this study contribute to an enhanced understanding of the dynamics of changes and preservation of aroma compounds and nutrients present during the processing of BRT.

Hierarchical structural modification of starch via non-thermal plasma: A state-of-the-art review

The hierarchical architecture of natural and processed starches with different surface and internal structures determines their final physicochemical properties. However, the oriented control of starch structure presents a significant challenge, and non-thermal plasma (cold plasma, CP) has gradually been used to design and tailor starch macromolecules, though without clear illustration. In this review, the multi-scale structure (i.e., chain-length distribution, crystal structure, lamellar structure, and particle surface) of starch is summarized by CP treatment. The plasma type, mode, medium gas and mechanism are also illustrated, as well as their sustainable food applications, such as in food taste, safety, and packaging. The effects of CP on the chain-length distribution, lamellar structure, amorphous zone, and particle surface/core of starch includes irregularity due to the complex of CP types, action modes, and reactive conditions. CP-induced chain breaks lead to short-chain distributions in starch, but this rule is no longer useful when CP is combined with other physical treatments. The degree but not type of starch crystals is indirectly influenced by CP through attacking the amorphous region. Furthermore, the CP-induced surface corrosion and channel disintegration of starch cause changes in functional properties for starch-related applications.

Effect of a Combination of Ultrasonic Germination and Fermentation Processes on the Antioxidant Activity and γ-Aminobutyric Acid Content of Food Ingredients

Whole-grain food ingredients enable the most balanced food products to be obtained, thus forming an important part of a healthy and sustainable diet. Wheat and barley grains are a traditional source of food ingredients for breads, breakfasts, drinks, and snacks in Russia. Such foods are suitable for all ages with many health benefits. However, the modern metropolitan citizen consumes large quantities of refined cereal products, thus impoverishing their diet. An alternative in dietary fortification could be sprouted and fermented food ingredients with an increased nutritional value. The present work was carried out to study the effect of a combination of germination with ultrasound treatment and fermentation with a complex starter of cereal crops on antioxidant activity and γ-aminobutyric acid content of food ingredients with the possibility of using them in the matrix of food products. In order to obtain germinated food ingredients, we used crops with the highest yield in the Ural region (Russia): two samples of soft spring wheat (Triticum aestivum L.) and a sample of spring barley grain (Hordeum vulgare L.). Obtaining food ingredients was divided into successive stages: ultrasonic treatment (22 ± 1.25 kHz) was performed by means of changing power and length of time (245 W/L, intensity for 5 min); germination and fermentation used complex starter “Vivo Probio”. The proposed technology of germination with haunting fermentation of cereal crops resulted in food ingredients with a more uniform distribution of granulometric composition, a low proportion of fine particles (4.62–104.60 µm) (p < 0.05) and large particles (418.60–592.00 µm) (p < 0.05). The particle size range (31.11–248.90 μm) (p < 0.05) was predominant. The germination and fermentation process resulted in 26 to 57% (p < 0.05) lower phytic acid content, 35 to 68% (p < 0.05) higher flavonoid content, 31 to 51% (p < 0.05) higher total antioxidant activity, 42.4 to 93.9% (p < 0.05) higher assimilability, and 3.1 to 4.7 times (p < 0.05) higher γ-aminobutyric acid content, which will allow production of food products with pronounced preventive action. The data was analyzed via one-way ANOVA analysis of variance using the free web-based software. The combination of the germination process with ultrasound treatment and subsequent fermentation with a complex starter can be used to support the development of healthful food products with increased GABA and antioxidant activity.

Analysis of Dynamics and Diversity of Microbial Community during Production of Germinated Brown Rice

Sprouts may be contaminated with different pathogenic and spoilage microorganisms, which lead far too easily to foodborne outbreaks. The elucidations of microbial profiles in germinated brown rice (BR) are important, but the changes in the microbial composition during germination are unknown. This study aimed to investigate the microbiota composition and to monitor the dominant microbial dynamics in BR during germination using both culture-independent and -dependent methods. BR samples (HLJ2 and HN) were collected from each stage of the germination processing. The populations of microbes (total viable counts, yeast/mold counts, Bacillus cereus, and Enterobacteriaceae) of two BR cultivars increased markedly with the prolongation of the germination time. High-throughput sequencing (HTS) showed that the germination process significantly influenced the microbial composition and reduced the microbial diversity. Similar microbial communities were observed between the HLJ2 and the HN samples, but with different microbial richness. The bacterial and fungal alpha diversity achieved the maximum for ungerminated samples and declined significantly after soaking and germination. During germination, Pantoea, Bacillus, and Cronobacter were the dominant bacterial genera, but Aspergillus, Rhizopus, and Coniothyrium dominated for the fungi in the BR samples. The predominance of harmful and spoilage microorganisms in BR during germination is mainly from contaminated seeds, which highlights the potential risk of foodborne illness from sprouted BR products. The results provide new insight into the microbiome dynamics of BR and may help to establish effective decontamination measures against pathogenic microorganisms during sprout production.

Role of Non-Thermal Plasma in Fusarium Inactivation and Mycotoxin Decontamination

Fusarium spp. is a well-studied pathogen with the potential to infect cereals and reduce the yield to maximum if left unchecked. For decades, different control treatments have been tested against different Fusarium spp. and for reducing the mycotoxins they produce and are well documented. Some treatments also involved integrated pest management (IPM) strategies against Fusarium spp. control and mycotoxin degradation produced by them. In this review article, we compiled different control strategies against different Fusarium spp. In addition, special focus is given to the non-thermal plasma (NTP) technique used against Fusarium spp. inactivation. In a separate group, we compiled the literature about the use of NTP in the decontamination of mycotoxins produced by Fusarium spp., and highlighted the possible mechanisms of mycotoxin degradation by NTP. In this review, we concluded that although NTP is an effective treatment, it is a nice area and needs further research. The possibility of a prospective novel IPM strategy against Fusarium spp. is also proposed.

Cold plasma technologies: Their effect on starch properties and industrial scale-up for starchmodification

Native starches have limited applications in the food industry due to their unreactive and insoluble nature. Cold plasma technology, including plasma-activated water (PAW), has been explored to modify starches to enhance their functional, thermal, molecular, morphological, and physicochemical properties. Atmospheric cold plasma and low-pressure plasma systems have been used to alter starches and have proven successful. This review provides an in-depth analysis of the different cold plasma setups employed for starch modifications. The effect of cold plasma technology application on starch characteristics is summarized. We also discussed the potential of plasma-activated water as a novel alternative for starch modification. This review provides information needed for the industrial scale-up of cold plasma technologies as an eco-friendly method of starch modification.

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Cold plasma technology could be an effective, sustainable alternative for starch modification.

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The extent of modification of starches from different botanical sources depends on the type of cold plasma technology used.

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For mainstream adoption of cold plasma modified starches, research on safety and consumer perception must be conducted.

Effect of high hydrostatic pressure on the edible quality, health and safety attributes of plant-based foods represented by cereals and legumes: a review

Consumers today are increasingly willing to reduce their meat consumption and adopt plant-based alternatives in their diet. As a main source of plant-based foods, cereals and legumes (CLs) together could make up for all the essential nutrients that humans consume daily. However, the consumption of CLs and their derivatives is facing many challenges, such as the poor palatability of coarse grains and vegetarian meat, the presence of anti-nutritional factors, and allergenic proteins in CLs, and the vulnerability of plant-based foods to microbial contamination. Recently, high hydrostatic pressure (HHP) technology has been used to tailor the techno-functionality of plant proteins and induce cold gelatinization of starch in CLs to improve the edible quality of plant-based products. The nutritional value (e.g., the bioavailability of vitamins and minerals, reduction of anti-nutritional factors of legume proteins) and bio-functional properties (e.g., production of bioactive peptides, increasing the content of γ-aminobutyric acid) of CLs were significantly improved as affected by HHP. Moreover, the food safety of plant-based products could be significantly improved as well. HHP lowered the risk of microbial contamination through the inactivation of numerous microorganisms, spores, and enzymes in CLs and alleviated the allergy symptoms from consumption of plant-based foods.

A Review of Microbial Decontamination of Cereals by Non-Thermal Plasma

Cereals, an important food for humans and animals, may carry microbial contamination undesirable to the consumer or to the next generation of plants. Currently, non-thermal plasma (NTP) is often considered a new and safe microbicidal agent without or with very low adverse side effects. NTP is a partially or fully ionized gas at room temperature, typically generated by various electric discharges and rich in reactive particles. This review summarizes the effects of NTP on various types of cereals and products. NTP has undisputed beneficial effects with high potential for future practical use in decontamination and disinfection.

Revisiting Non-Thermal Food Processing and Preservation Methods-Action Mechanisms, Pros and Cons: A Technological Update (2016-2021)

The push for non-thermal food processing methods has emerged due to the challenges associated with thermal food processing methods, for instance, high operational costs and alteration of food nutrient components. Non-thermal food processing involves methods where the food materials receive microbiological inactivation without or with little direct application of heat. Besides being well established in scientific literature, research into non-thermal food processing technologies are constantly on the rise as applied to a wide range of food products. Due to such remarkable progress by scientists and researchers, there is need for continuous synthesis of relevant scientific literature for the benefit of all actors in the agro-food value chain, most importantly the food processors, and to supplement existing information. This review, therefore, aimed to provide a technological update on some selected non-thermal food processing methods specifically focused on their operational mechanisms, their effectiveness in preserving various kinds of foods, as revealed by their pros (merits) and cons (demerits). Specifically, pulsed electric field, pulsed light, ultraviolet radiation, high-pressure processing, non-thermal (cold) plasma, ozone treatment, ionizing radiation, and ultrasound were considered. What defines these techniques, their ability to exhibit limited changes in the sensory attributes of food, retain the food nutrient contents, ensure food safety, extend shelf-life, and being eco-friendly were highlighted. Rationalizing the process mechanisms about these specific non-thermal technologies alongside consumer education can help raise awareness prior to any design considerations, improvement of cost-effectiveness, and scaling-up their capacity for industrial-level applications.

Effect of dielectric barrier discharge cold plasma treatments on flavor fingerprints of brown rice

A non-thermal processing method was developed to promote preservation of brown rice using dielectric barrier discharge cold plasma (DBD-CP). Physicochemical properties including free fatty acid (FFA) content, surface color change, volatile organic components (VOCs) and flavor fingerprints were evaluated in brown rice submitted to DBD-CP. FFA levels were 25.2% lower in treated samples compared to the control, and a more stable surface color was obtained at the end of the storage period. A total of 35 major VOCs could be detected in treated samples, and reduced levels of hexanal can be used as an indicator of DBD-CP treatment in brown rice during storage. Moreover, the flavor fingerprints in DBD-CP treated groups can be successfully distinguished through headspace gas chromatography ion mobility spectrometry. Collectively, application of DBD-CP treatment could be utilized as a feasible approach to promote stabilization of brown rice and preserve flavor during storage.

Effects of germination and roasting on physicochemical and sensory characteristics of brown rice for tea infusion

Germinated brown rice was roasted for the preparation of tea. The germination induced substantial increases in reducing sugars (from 3224.06 to 5028.80 mg/100 g), free amino acids (from 62.51 to 165.07 mg/100 g), volatile compounds, and phenolics (10.06 to 14.27 mg GAE/100 g). Roasting decreased the residual contents of free amino acids and reducing sugars, but produced the volatiles and phenolics. Browning index was slightly decreased by the germination (from 22.69 to 20.13), but significantly increased by the subsequent roasting. The germinated BR (GBR) was more susceptible to roasting than native BR. Acrylamide content in the roasted GBR was significantly lower than that in the roasted BR, because of the lower asparagine content in GBR. Sensory evaluation revealed that a mild roasting for 5 min at 230 °C after germination for 2 days was appropriate to produce a brown rice tea.