High hydrostatic pressure treatment for manufacturing of red bean powder: A comparison with the thermal treatment

Application of legumes in plant-based milk alternatives: a review of limitations and solutions

In recent years, a global shift has been observed toward reducing the consumption of animal-derived foods in favor of healthier and more sustainable dietary choices. This has led to a steady growth in the market for plant-based milk alternatives (PBMAs). Projections suggest that this market will reach a value of USD 69.8 billion by 2030. Legumes, being traditional and nutritious ingredients for PMBAs, are rich in proteins, dietary fibers, and other nutrients, with potential health benefits such as anticancer and cardiovascular disease prevention. In this review, the application of 12 legumes in plant-based milk alternatives was thoroughly discussed for the first time. However, compared to milk, processing of legume-based beverages can lead to deficiencies such as nutritional imbalance, off-flavor, and emulsion stratification. Considering the potential and challenges associated with legume-based beverages, this review aims to provide a scientific comparison between legume-based beverages and cow's milk in terms of nutritional quality, organoleptic attributes and stability, and to summarize ways to improve the deficiencies of legume-based beverages in terms of raw materials and processing method improvements. In conclusion, the legume-based beverage industry will be better enhanced and developed by improving the issues.

Pretreatments and Particle Size on the Glycemic Index and Rheological and Functional Food Properties of Bean Flours

The beans' protein and slow-digesting carbohydrate content make it an appealing choice for healthy food development. However, its properties are influenced by the flour extraction processes. This study is aimed at evaluating the effect of particle size and three pretreatments-drying (D), soaking + cooking + dehydrating 3 h (SCD3), and soaking + cooking + dehydrating 24 h (SCD24)-on the estimated glycemic index (eGI) compared with raw bean flour (R). The methodology covered water absorption (WAI), water solubility (WSI), amylose content, starch digestibility, eGI, phenolic quantification, and rheology. The results showed that WAI correlated negatively with WSI and amylose, varying among pretreatments and sizes. WAI increased as D < SCD24 < SCD3 < R. Glucose release (HI) differed between fine (125 μm) and coarse fractions (242 μm), with SCD24 and R showing the lowest eGI (22.8-24.2). SCD3 had the highest flavonoid concentration, while R and D had more quercetin-3-glucoside. SCD24 displayed higher elastic/viscous moduli than R. Bean flours from all treatments had low GI and contained bioactive polyphenols (catechin, epicatechin, ferulic acid, quercetin). The optimal treatment was SCD24, particularly in the coarse fraction, showing potential for functional food development and novel applications such as precision nutrition.

Self-assembly of coconut residue fiber with chitosan: Effect of three pre-treatments on the self-assembly process and bile salt adsorption

Self-assembly with chitosan is a promising method for improving bile salt (BS) adsorption by coconut residue fiber (CRF). To study the self-assembly process, three pre-treatments were performed and investigated using microrheological analysis. The effects of the pretreatments on the self-assembly of CRF and the BS adsorption were evaluated. During self-assembly, CRFs underwent Brownian-like motion, and the addition of chitosan facilitated the formation of inter-particle interactions between CRFs in the system. These interactions were small in extent, large in number, and slow to state change, in addition to relatively high strength and longer maintenance, all of which contributed to the binding to BS. The conventional pretreatments failed to effectively improve the BS adsorption of the self-assembled CRFs and weakened the inter-particle interactions in the system. These results suggest that chitosan assists in the adsorption of self-assembled CRF to BS through a combination of H-bonds and other weak intermolecular forces.

Comparison between the use of hydrocolloids (xanthan gum) and high-pressure processing to obtain a texture-modified puree for dysphagia

Enriched lentil protein vegetable purees (10% zucchini, 10% carrots, 2.5% extra virgin olive oil and 21.8% lentil protein concentrate) suitable for people with dysphagia were developed with 0.8% xanthan gum (XG) or 600 MPa/5 min high pressure processing (HPP) treatment with the aim of comparing their rheological and textural properties. Selection of the appropriate XG % and HPP conditions was made by performing initial pilot trials. Purees showed a good nutritional profile (12% protein, 3.4% fiber, 100 Kcal/100 g), being adequate for people with dysphagia. Microbiological testing of HPP treated purees indicated that it has a good shelf-life under refrigerated conditions 14 days). Both types of purees showed a gel-like character (tan delta 0.161-0.222) and higher firmness, consistency and cohesiveness than control samples. Comparing XG and HPP samples at time 0, HPP treated purees showed the highest stiffness ( G'), the lowest deformability capacity (yield strain_LVR) and the lowest structural stability (yield stress_LVR). With storage, HPP treatment samples showed significant increases in all rheological and textural parameters. These results confirm the suitability of HPP as an alternative technology to hydrocolloids for the obtained dysphagia dishes.

Legume Protein Extracts: The Relevance of Physical Processing in the Context of Structural, Techno-Functional and Nutritional Aspects of Food Development

Legumes are sustainable protein-rich crops with numerous industrial food applications, which give them the potential of a functional food ingredient. Legume proteins have appreciable techno-functional properties (e.g., emulsification, foaming, water absorption), which could be affected along with its digestibility during processing. Extraction and isolation of legumes’ protein content makes their use more efficient; however, exposure to the conditions of further use (such as temperature and pressure) results in, and significantly increases, changes in the structural, and therefore functional and nutritional, properties. The present review focuses on the quality of legume protein concentrates and their changes under the influence of different physical processing treatments and highlights the effect of processing techniques on the structural, functional, and some of the nutritional, properties of legume proteins.

Influence of high‐pressure processing on nutritional composition and bioactive compounds of Phaseolus coccineus L

The influence of high-pressure processing (HPP) prior to cooking on nutritional composition and bioactive compounds content of four varieties of Phaseolus coccineus L. was studied. Cooking and HPP+C increased the protein content. However, minerals, total carbohydrates, ciceritol and α-galactosides were reduced. Fat was not affected by cooking but decreased after HPP+C. For dietary fiber, the behavior observed was different depending on the sample and the treatment applied. HPP+C could be considered a good processing technology to retain the advantageous lower myo-inositol phosphates isoforms and supply prebiotic oligosaccharides. The trypsin inhibitors activity was lower in the cooked and HPP+C samples; however, there were no significant differences between both thermal treatments. Thus, HPP+C reduced cooking time and preserving or improving the nutritional composition of the beans and their bioactive compounds content.

Plant-based milk: unravel the changes of the antioxidant index during processing and storage - a review

As a nutrient rich emulsion extracted from plant materials, plant-based milk (PBM) has been the latest trend and hot topic in the food industry due to the growing awareness of consumers toward plant-based products in managing the environmental (carbon footprint and land utility), ethical (animal well-fare) and societal (health-conscious) issues. There have been extensive studies and reviews done to discuss the distinct perspective of PBM including its production, health effects and market acceptance. However, not much has been emphasized on the valuable antioxidants present in PBM which is one of the attributes making them stand apart from dairy milk. The amounts of antioxidants in PBM are important. They offered tremendous health benefits in maintaining optimum health and reducing the risk of various health disorders. Therefore, enhancing the extraction of antioxidants and preserving their activity during production and storage is important. However, there is a lack of a comprehensive review of how these antioxidants changes in response to different processing steps involved in PBM production. Presumably, antioxidants in PBM could be potentially lost due to thermal degradation, oxidation or leaching into processing water. Hence, this paper aims to fill the gaps by addressing an extensive review of how different production steps (germination, roasting, soaking, blanching, grinding and filtration, and microbial inactivation) affect the antioxidant content in PBM. In addition, the effect of different microbial inactivation treatments (thermal or non-thermal processing) on the alteration of antioxidant in PBM was also highlighted. This paper can provide useful insight for the industry that aims in selecting suitable processing steps to produce PBM products that carry with them a health declaration.

Legume Seed Protein Digestibility as Influenced by Traditional and Emerging Physical Processing Technologies

The increased consumption of legume seeds as a strategy for enhancing food security, reducing malnutrition, and improving health outcomes on a global scale remains an ongoing subject of profound research interest. Legume seed proteins are rich in their dietary protein contents. However, coexisting with these proteins in the seed matrix are other components that inhibit protein digestibility. Thus, improving access to legume proteins often depends on the neutralisation of these inhibitors, which are collectively described as antinutrients or antinutritional factors. The determination of protein quality, which typically involves evaluating protein digestibility and essential amino acid content, is assessed using various methods, such as in vitro simulated gastrointestinal digestibility, protein digestibility-corrected amino acid score (IV-PDCAAS), and digestible indispensable amino acid score (DIAAS). Since most edible legumes are mainly available in their processed forms, an interrogation of these processing methods, which could be traditional (e.g., cooking, milling, extrusion, germination, and fermentation) or based on emerging technologies (e.g., high-pressure processing (HPP), ultrasound, irradiation, pulsed electric field (PEF), and microwave), is not only critical but also necessary given the capacity of processing methods to influence protein digestibility. Therefore, this timely and important review discusses how each of these processing methods affects legume seed digestibility, examines the potential for improvements, highlights the challenges posed by antinutritional factors, and suggests areas of focus for future research.

A review of thermosensitive antinutritional factors in plant-based foods

Legumes and cereals account for the vast proportion of people's daily intake of plant-based foods. Meanwhile, a large number of antinutritional factors in legumes and cereals hinder the body absorption of nutrients and reduce the nutritional value of food. In this paper, the antinutritional effects, determination, and passivation methods of thermosensitive antinutritional factors such as trypsin inhibitors, urease, lipoxygenase, and lectin were reviewed to provide theoretical help to reduce antinutritional factors in food and improve the utilization rate of plant-based food nutrition. Since trypsin inhibitors and lectin have been more extensively studied and reviewed previously, the review mainly focused on urease and lipoxygenase. This review summarized the information of thermosensitive antinutritional factors, trypsin inhibitors, urease, lipoxygenase, and lectin, in cereals and legumes. The antinutritional effects, and physical and chemical properties of trypsin inhibitors, urease, lipoxygenase, and lectin were introduced. At the same time, the research methods for the detection and inactivation of these four antinutritional factors were also summarized in the order of research conducted time. The rapid determination and inactivation of antinutrients will be the focus of attention for the food industry in the future to improve the nutritional value of food. Exploring what structural changes could passivation technologies bring to antinutritional factors will provide a theoretical basis for further understanding the mechanisms of antinutritional factor inactivation. PRACTICAL APPLICATIONS: Antinutritional factors in plant-based foods hinder the absorption of nutrients and reduce the nutritional value of the food. Among them, thermosensitive antinutritional factors, such as trypsin inhibitors, urease, lipoxygenase, and lectins, have a high proportion among the antinutritional factors. In this paper, we investigate thermosensitive antinutritional factors from three perspectives: the antinutritional effect of thermosensitive antinutritional factors, determination, and passivation methods. The current passivation methods for thermosensitive antinutritional factors revolve around biological, physical, and chemical aspects, and their elimination mechanisms still need further research, especially at the protein structure level. Reducing the level of antinutritional factors in the future food industry while controlling the loss of other nutrients in food is a goal that needs to be balanced. This paper reviews the antinutritional effects of thermosensitive antinutritional factors and passivation methods, expecting to provide new research ideas to improve the nutrient utilization of food.

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.

Effect of high-pressure pre-soaking on texture and retrogradation properties of parboiled rice

BACKGROUND

The poor palatability, low digestibility, and unpleasant color of parboiled rice (PR) have severely hampered its acceptance by consumers. It is hence necessary and urgent to develop a new method for producing high-quality PR. In the current study, the effect of high hydrostatic pressure (HHP) pre-soaking on the color, textural properties, and the degree of retrogradation of PR was investigated.

RESULTS

With HHP from 100 to 500 MPa, the water adsorption rate increased and cooking time decreased. Parboiled rice samples presented higher lightness scores (L) and had lower color intensity (B). Compared with a control group, PR samples treated with high-pressure pre-soaking showed a reduction of hardness values from 0.69% to 32.99%, and gumminess values also decreased from 8.58% to 33.62%. The differential scanning calorimetry (DSC) results indicated that the enthalpy values of PR samples decreased after high pressure pre-soaking. The molecular structure of PR characterized by Fourier transform infrared spectrometry confirmed that HHP pre-soaking could decrease the retrogradation level.

CONCLUSION

The findings outlined above suggest that the texture and retrogradation properties of PR were improved after high-pressure pre-soaking. © 2021 Society of Chemical Industry.

Effects of Different Processing Methods and Internal Components on Physicochemical Properties and Glycemic Index of Adzuki Bean Powder

The estimated glycemic index (eGI) value of adzuki bean powder prepared by steamed cooking (SC), extruded cooking (EC) and roller cooking (RC) was studied comparatively. Results showed that RC had the highest eGI, with 80.1, and both EC and SC resulted in a lower eGI value of 70.0 and 49.7, respectively. Compared with the EC and RC methods, the SC method provided a more intact physical barrier for starch digestion, resulting in a less destroyed cell structure. As the essential components that form the cell wall, the study further investigated the effects of protein and fiber on physicochemical properties, in vitro starch digestibility and the eGI of adzuki bean powder processed with the SC method. Viscozyme and Protamax were used to obtain the deprotein and defiber samples. Results showed that the SC treatment with Viscozyme and Protamax, respectively, had significant effects on in vitro starch digestibility. The eGI of different samples were given as follows: steamed cooking adzuki bean powder (49.7) < deproteined adzuki bean powder (60.5) < defibered adzuki bean powder (83.1), which indicates that fiber may have a greater influence on the eGI than protein.

Reactivity of flavanols: Their fate in physical food processing and recent advances in their analysis by depolymerization

Flavanols, a subgroup of polyphenols, are secondary metabolites with antioxidant properties naturally produced in various plants (e.g., green tea, cocoa, grapes, and apples); they are a major polyphenol class in human foods and beverages, and have recognized effect on maintaining human health. Therefore, it is necessary to evaluate their changes (i.e., oxidation, polymerization, degradation, and epimerization) during various physical processing (i.e., heating, drying, mechanical shearing, high-pressure, ultrasound, and radiation) to improve the nutritional value of food products. However, the roles of flavanols, in particular for their polymerized forms, are often underestimated, for a large part because of analytical challenges: they are difficult to extract quantitatively, and their quantification demands chemical reactions. This review examines the existing data on the effects of different physical processing techniques on the content of flavanols and highlights the changes in epimerization and degree of polymerization, as well as some of the latest acidolysis methods for proanthocyanidin characterization and quantification. More and more evidence show that physical processing can affect content but also modify the structure of flavanols by promoting a series of internal reactions. The most important reactivity of flavanols in processing includes oxidative coupling and rearrangements, chain cleavage, structural rearrangements (e.g., polymerization, degradation, and epimerization), and addition to other macromolecules, that is, proteins and polysaccharides. Some acidolysis methods for the analysis of polymeric proanthocyanidins have been updated, which has contributed to complete analysis of proanthocyanidin structures in particular regarding their proportion of A-type proanthocyanidins and their degree of polymerization in various plants. However, future research is also needed to better extract and characterize high-polymer proanthocyanidins, whether in their native or modified forms.

Effect of Food Processing on Antioxidant Potential, Availability, and Bioavailability

Antioxidants are understood to play a key role in disease prevention; because of this, research and interest in these compounds are ever increasing. Antioxidative phytochemicals from natural sources are preferred, as some negative implications have been associated with synthetic antioxidants. Beans, nuts, seeds, fruits, and vegetables, to name a few, are important sources of phytochemicals, which have purported health benefits. The aforementioned plant sources are reportedly rich in bioactive compounds, most of which undergo some form of processing (boiling, steaming, soaking) prior to consumption. This article briefly reviews selected plants (beans, nuts, seeds, fruits, and vegetables) and the effects of processing on the antioxidant potential, availability, and bioavailability of phytochemicals, with research from our laboratory and other studies determining the health benefits of and processing effects on bioactive compounds.

Formation of furan in baby food products: Identification and technical challenges

Furan is generally produced during thermal processing of various foods including baked, fried, and roasted food items such as cereal products, coffee, canned, and jarred prepared foods as well as in baby foods. Furan is a toxic and carcinogenic compound to humans and may be a vital hazard to infants and babies. Furan could be formed in foods through thermal degradation of carbohydrates, dissociation of amino acids, and oxidation of polyunsaturated fatty acids. The detection of furan in food products is difficult due to its high volatility and low molecular weight. Headspace solid-phase microextraction coupled with gas chromatography/mass spectrometer (GC/MS) is generally used for analysis of furan in food samples. The risk assessment of furan can be characterized using margin of exposure approach (MOE). Conventional strategies including cooking in open vessels, reheating of commercially processed foods with stirring, and physical removal using vacuum treatment have remained unsuccessful for the removal of furan due to the complex production mechanisms and possible precursors of furan. The innovative food-processing technologies such as high-pressure processing (HPP), high-pressure thermal sterilization (HPTS), and Ohmic heating have been adapted for the reduction of furan levels in baby foods. But in recent years, only HPP has gained interest due to successful reduction of furan because of its nonthermal mechanism. HPP-treated baby food products are commercially available from different food companies. This review summarizes the mechanism involved in the formation of furan in foods, its toxicity, and identification in infant foods and presents a solution for limiting its formation, occurrence, and retention using novel strategies.

Effect of Instant Controlled Pressure-Drop (DIC), Cooking and Germination on Non-Nutritional Factors of Common Vetch (Vicia sativa spp.)

Legumes are widely consumed by humans, being an important source of nutrients; however, they contain non-nutritional factors (NNFs), such as phytic acid (IP6), raffinose, stachyose, total phenolic compounds, condensed tannins, and flavonoids, that have negative effects on human health. Although vetches (Vicia sativa) are widely cultivated, they are not intended for human feeding due to their contents of NNF. Usually, the NNF are removed by cooking or germinating; however, germination is a process that requires extended time, and cooking may compromise the viability of some nutrients. To promote vetches for human consumption, the effect of the Instant Controlled Pressure Drop (DIC) process was studied as an alternative to cooking and germinating to decrease NNF contents. Results showed that compared to raw vetches, DIC treatment reduced total phenolic compounds (48%), condensed tannins (28%), flavonoids (65%), IP6 (92%), raffinose (77%), and stachyose (92%). These results are very similar to the ones achieved by traditional ways of removing NNF.

Healthy expectations of high hydrostatic pressure treatment in food processing industry

High hydrostatic pressure processing (HPP) is a non-thermal pasteurization technology which has already been applied in the food industries. Besides maintaining the food safety and quality, HPP also has potential applications in the enhancement of the health benefits of food products. This study examines the current progress of research on the use of HPP in the development of health foods. Through HPP, the nutritional value of food products can be enhanced or retained, including promotes the biosynthesis of γ-aminobutyric acid (GABA) in the food materials, retains immunoglobulin components in dairy products, increases resistant starch content in cereals, and reduces the glycemic index of fruit and vegetable products, which facilitates better control of blood glucose levels and decreases calorie intake. HPP can also be utilized as a hurdle technology in combination with existing processing technologies for the development of low-sodium food products and the maintenance of microbial safety, thereby lowering the risk of triggering cardiovascular disease. Additionally, HPP can be used to enhance the diversity of probiotic food products. Appropriate sporogenous probiotics can be screened and added to various high-pressure processed food products as a certain bacterial count is still retained in the products after HPP. As HPP causes physical damage to the structures of food products, it can also be used as a synergistic extraction technology to enhance the extraction efficiency of functional components, thereby reducing extraction time. By applying HPP in the extraction of functional components from food waste, the production costs of such components can be effectively reduced. This study provides a summary of the mechanisms by which HPP enhances the health benefits of food products and the current progress of relevant research. HPP possesses huge potential in the development of novel health foods and may provide an abundance of benefits to human health in the future.

Manipulation of the dry bean (Phaseolus vulgaris L.) matrix by hydrothermal and high-pressure treatments: Impact on in vitro bile salt-binding ability

The capacity of high-fiber foods to sequester BS during digestion is considered a mechanism to lower serum-cholesterol. We investigated the effect of hydrothermal (HT) and high-hydrostatic-pressure (HHP) on the bile salt (BS)-binding ability of dry beans, and how this relates to changes in bean microstructure, fiber content (insoluble-IDF/soluble-SDF), and viscosity. HT and HHP-600 MPa led to significant IDF reduction, including resistant starch (RS), whereas 150-450 MPa significantly increased RS, without modifying IDF/SDF content. Microscopy analysis showed that heating disrupted the bean cell wall integrity, protein matrix and starch granules more severely than 600 MPa; however, tightly-packed complexes of globular starch granules-protein-cell wall fiber formed at HHP ≤ 450 MPa. While HT significantly reduced BS-binding efficiency despite no viscosity change, HHP-treatments maintained or enhanced BS-retention. 600 MPa-treatment induced the maximum BS-binding ability and viscosity. These results demonstrate that BS-binding by beans is not solely based on their fiber content or viscosity, but is influenced by additional microstructural factors.

Emerging chemical and physical disinfection technologies of fruits and vegetables: a comprehensive review

With a growing demand for safe, nutritious, and fresh-like produce, a number of disinfection technologies have been developed. This review comprehensively examines the working principles and applications of several emerging disinfection technologies. The chemical treatments, including chlorine dioxide, ozone, electrolyzed water, essential oils, high-pressure carbon dioxide, and organic acids, have been improved as alternatives to traditional disinfection methods to meet current safety standards. Non-thermal physical treatments, such as UV-light, pulsed light, ionizing radiation, high hydrostatic pressure, cold plasma, and high-intensity ultrasound, have shown significant advantages in improving microbial safety and maintaining the desirable quality of produce. However, using these disinfection technologies alone may not meet the requirement of food safety and high product quality. Several hurdle technologies have been developed, which achieved synergistic effects to maximize lethality against microorganisms and minimize deterioration of produce quality. The review also identifies further research opportunities for the cost-effective commercialization of these technologies.

Understanding the Relations Among the Storage, Soaking, and Cooking Behavior of Pulses: A Scientific Basis for Innovations in Sustainable Foods for the Future

The world faces challenges that require sustainable solutions: food and nutrition insecurity; replacement of animal-based protein sources; and increasing demand for convenient, nutritious, and health-beneficial foods; as well as functional ingredients. The irrefutable potential of pulses as future sustainable food systems is undermined by the hardening phenomenon that develops upon their storage under adverse conditions of temperature and relative humidity. Occurrence of this phenomenon indicates storage instability. In this review, the application of a material science approach, in particular the glass transition temperature concept, is presented to explain phenomena of storage instability such as the occurrence of hardening and loss of viability under adverse storage conditions. In addition to storage (in)stability, application of this concept during processing of pulses is discussed. The state-of-the-art on how hardening occurs, that is, mechanistic insights, is provided, including a critical evaluation of some of the existing postulations using recent research findings. Moreover, the influence of hardening on the properties and processing of pulses is included. Prevention of hardening and curative actions for pulses affected by the hardening phenomenon are described in addition to the current trends on uses of pulses and pulse-derived products. Based on the knowledge progress presented in this review, suggestions for the future include: first, the need for innovation toward implementation of recommended solutions for the prevention of hardening; second, the optimization of the identified most effective and efficient curative action against hardening; and third, areas to focus on for elucidation of mechanisms of hardening, although existing analytical methods require advancement.

Reduction of β-ODAP and IP6 contents in Lathyrus sativus L. seed by high hydrostatic pressure

Grass pea (Lathyrus sativus L.) seeds contain an endogenous neurotoxic non-proteinogenic amino acid, β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP), a major limiting factor-for their human consumption. Furthermore, phytate (IP₆), a well-known antinutrient is present in concentration capable of hindering bioavailability of iron (Fe), zinc (Zn), calcium (Ca), phosphorus (P) and other micronutrients from the seeds. Due to the reported capability of high hydrostatic pressure (HHP) to reduce the content of certain antinutritional/toxic agents in seeds and grains, the impact of HHP on the reduction of β-ODAP and IP₆ were investigated. The contents of β-ODAP of accessions from different regions in Ethiopia were found to be in the range of 51.94 to 806.52 mg/100 g. Accession (GF₁- Alemu, AK) exhibiting the highest β-ODAP content was selected for HHP treatment in soaked and batter forms using Central Composite Face Centered Design of experiments. The best HHP conditions in respect to β-ODAP reduction were also applied to the accession (GP-240038) with the lowest β-ODAP-content, a genetically improved variety (Wassie) and a variety from Germany (GR). The HHP treatment at 600 MPa for 25 min of seeds soaked for 6 h and 12 h exhibited the maximum reduction of β-ODAP (232.11 mg/100 g) and IP₆ (21.11 mg/100 g) respectively. The combined incremental effect of pressure and soaking time resulted in a more significant (p ≤ .001) reduction in both compounds than the interaction of pressure with holding time (p ≤ .05). A reduction of β-ODAP from 36.00 to 71.22% by soaked-HHP treatment was observed. β-ODAP reductions were always higher for soaked compared to batter grass pea seeds. IP₆ contents after HHP treatment ranged from 33.65 mg/100 g to nill. It can be concluded that pressure, soaking and holding time as well as the grass pea seed accession/variety had great impact on molecular structure changes, enhancement of enzyme activity and reduction in β-ODAP and IP₆ content.

Development of ginseng powder using high hydrostatic pressure treatment combined with UV-TiO2 photocatalysis

Background

Korean ginseng (Panax ginseng Meyer) powder is in rising demand because powder forms of foods are convenient to handle and are highly preservable. However, ginseng powder (GP) manufactured using the conventional process of air drying and dry milling suffers nutrient destruction and a lack of microbiological safety. The objective of this study was to prepare GP using a novel process comprised of UV-TiO₂ photocatalysis (UVTP) as a prewashing step, wet grinding, high hydrostatic pressure (HHP), and freeze-drying treatments.

Methods

The effects of UVTP and HHP treatments on the microbial population, ginsenoside concentration, and physiological characteristics of GP were evaluated.

Results

When UVTP for 10 min and HHP at 600 MPa for 5 min were combined, initial 4.95 log CFU/g-fw counts of total aerobes in fresh ginseng were reduced to lower than the detection limit. The levels of 7 major ginsenosides in UVTP-HHP–treated GP were significantly higher than in untreated control samples. Stronger inhibitory effects against inflammatory mediator production and antioxidant activity were observed in UVTP-HHP–treated GP than in untreated samples. There were also no significant differences in CIELAB color values of UVTP-HHP–treated GP compared with untreated control samples.

Conclusion

Combined processing of UVTP and HHP increased ginsenoside levels and enhanced the microbiological safety and physiological activity of GP.