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[Display omitted] • Starch and protein hydrolysis were measured using gastric-small intestinal kinetics. • Drying led to faster particle size reduction and increased starch digestibility. • Fine cracker and puree had high starch digestibility due to small particle size. • Coarse puree had slow gastric emptying, large size, and low starch digestibility. Chickpeas are an agriculturally-important legume that are an excellent source of protein, fiber, and minerals. Developing chickpea-based snacks could provide consumers with snack products rich in protein and other nutrients. In this study, chickpea puree (high moisture content) and cracker (low moisture content) were each produced with large (7 mm sieve; coarse) or small (2 mm sieve; fine) particle size to investigate the impact of initial particle size and moisture content on particle breakdown, starch hydrolysis, and protein hydrolysis during in vitro digestion. All treatments underwent static in vitro oral digestion, dynamic gastric digestion in the Human Gastric Simulator (HGS), and static in vitro small intestinal digestion. The emptying rate from the HGS was significantly (p < 0.05) higher for fine puree compared to the other treatments, due to higher saturation ratio and smaller initial particle size. The reducing sugars and free amino groups released (representing starch and protein hydrolysis, respectively) from fine puree were higher than coarse puree, and fine cracker was higher than coarse cracker due to the influence of initial particle size. For example, after 360 min total in vitro digestion, the starch hydrolysis of the fine cracker (48.1 ± 3.2%) was significantly higher than (p < 0.05) the coarse cracker (36.3 ± 5.8%). Overall, crackers had higher protein and starch hydrolysis compared to puree in the liquid phase during digestion. The study showed that both the smaller initial particle size and drying significantly (p < 0.05) increased the particle size reduction during gastric digestion and starch and protein digestibility in chickpea-based snacks. [ABSTRACT FROM AUTHOR]

Glass transition temperature ( T g ) and sorption isotherms can be used to establish state diagrams that help to assess storage conditions to keep the food as an amorphous material in a glassy state. In this study, state diagrams and mechanical properties were assessed to predict the storage conditions of mangoes dried by 1) air-drying; 2) freeze-drying; 3) vacuum-drying and 4) conductive multi-flash drying (KMFD - four cycles of heating/vacuum pulse followed by vacuum-drying). Dried mangoes showed a typical sorption isotherm behavior of hygroscopic materials. In the relative humidity (RH) range investigated (between 11.3% and 90.3%), T g of processed samples decreased from 44 °C to −68 °C, due to the plasticizing effect of water. Dried mangoes stayed structurally stable at room temperature (25 °C) if storage RH was kept at 25%, in this conditions the moisture content was 0.036 g g −1 (d.b.). The puncture tests results confirmed that, at room temperature, samples stored at RH higher than 30% lost their crispness. [ABSTRACT FROM AUTHOR]

Abstract: In multi‐flash drying, the pressure drop applied during the vacuum pulse and the number of heating vacuum pulses cycles (HVP) influence the fruit microstructure and texture. In this work, the effects of conductive multi‐flash drying (KMFD) process variables on the drying kinetics, physical properties, and microstructure of mango slices were assessed. Different slopes of pressure drop (vacuum pulses of 0.98, 1.59, and 2.55 kPa s−1) and the number of HVP cycles (14 and 18 cycles for KMFD and a process with the application of 4 cycles followed by vacuum‐drying KMFD‐VD) were investigated. The number of HVP cycles allows obtaining both soft and crispy mangoes. Higher pressure drop slopes resulted in fruits with increased porosities (≈60%), compared with samples dried using the lower pressure drop slope (≈50%). The KMFD and KMFD‐VD drying curves were similar, indicating that KMFD‐VD presents operational advantages for obtaining dried fruits, reducing the number of heating‐vacuum pulses. Practical applications: Some fruits and vegetables have a short shelf life that limits their commercialization as fresh products and increase postharvest losses. Dehydration is an interesting alternative to the development of new products of fruits and vegetables with added value. In particular, the multi‐flash drying is an innovative drying process based on the application of multiple cycles of heating‐vacuum pulse to a solid food. Fruits and vegetables samples are heated (i.e., by heat conduction for the conductive multi‐flash drying—KMFD) at moderate temperatures and submitted to a vacuum pulse, which causes flash drying and sample cooling. This method allows maintaining in dried products good physical–chemical properties and improving its texture. Moreover, according to the number of heating‐vacuum pulse cycles and the pressure drop applied during these vacuum pulses, it is possible to obtain soft or crispy fruits. Thus, these variables can be used to control texture and produce high quality dried fruit. [ABSTRACT FROM AUTHOR]

Impregnation methods combined with drying (convective- or freeze-) were used for producing calcium-fortified pineapples snacks. Three impregnation alternative were evaluated: I) at atmospheric pressure for 20 min; II) applying 10 min of vacuum (13.33 kPa) to a container with pineapple samples immersed into the impregnating solution followed by 10 min of impregnation at atmospheric pressure; and III) applying vacuum impregnation followed by vacuum pulses (6.70 kPa) after removing the samples from the impregnating solution. The impregnating solution concentration was 1 g Ca 2+ 100 ml −1 prepared with CaCl 2 . The influence of the impregnation method on the kinetics of convective-drying and on porosity, shrinkage, glass transition temperature, water sorption isotherms, texture and microstructure of convective-dried and freeze-dried pineapple samples were determined. After drying, vacuum-impregnated products presented 91% higher concentration of Ca 2+ than pineapples impregnated at atmospheric pressure (equal total processing time). Calcium chloride impregnation increased the drying rates and positively influenced the physical properties of the convective-dried product. The combination of vacuum impregnation and drying is a suitable way for the production of calcium-fortified pineapples, which are porous-and-crunchy, with high glass transition temperature favouring its preservation during storage. [ABSTRACT FROM AUTHOR]

Global consumption of nori, a widely consumed commercial edible algal film, is predominant in Asian countries. As the demand for Asian cuisine rises in Brazil, there is a growing need to explore alternatives to importation, such as producing edible films using seaweeds from the Brazilian coast—specifically Ulva lactuca and Kappaphycus alvarezii. In this study, seaweed film formulations varied in concentrations, from 80% U. lactuca and 20% K. alvarezii to an equal proportion of 50% of each alga, heating at 90°C for 3 and 5 minutes. Results showed that the filmogenic suspensions had a pseudoplastic behavior, with viscosity decreasing as K. alvarezii concentration increased. The resistance of heated gels increased with higher K. alvarezii concentrations and prolonged heating times. Surface uniformity improved with elevated K. alvarezii concentration and extended heating time. As K. alvarezii concentration increased, films exhibited less intense coloration, heightened transparency, and increased solubility. Films with higher K. alvarezii content demonstrated greater tensile strength, albeit without an increase in elongation capacity. Sorption isotherms exhibited a characteristic Type II pattern, and modeling using the GAB model suggested stronger bonds in treatments with extended heating times. Despite the need for enhanced flexibility, the results indicate potential applications in snacks or as alternatives to nori. Notably, these films were produced solely with seaweeds and water, aligning with Nori's minimalistic approach. Treatments with a concentration of 60% U. lactuca and 40% K. alvarezii proved to be the most promising. This study lays the groundwork for future research in developing edible films derived from seaweeds.Graphical abstract: Global consumption of nori, a widely consumed commercial edible algal film, is predominant in Asian countries. As the demand for Asian cuisine rises in Brazil, there is a growing need to explore alternatives to importation, such as producing edible films using seaweeds from the Brazilian coast—specifically Ulva lactuca and Kappaphycus alvarezii. In this study, seaweed film formulations varied in concentrations, from 80% U. lactuca and 20% K. alvarezii to an equal proportion of 50% of each alga, heating at 90°C for 3 and 5 minutes. Results showed that the filmogenic suspensions had a pseudoplastic behavior, with viscosity decreasing as K. alvarezii concentration increased. The resistance of heated gels increased with higher K. alvarezii concentrations and prolonged heating times. Surface uniformity improved with elevated K. alvarezii concentration and extended heating time. As K. alvarezii concentration increased, films exhibited less intense coloration, heightened transparency, and increased solubility. Films with higher K. alvarezii content demonstrated greater tensile strength, albeit without an increase in elongation capacity. Sorption isotherms exhibited a characteristic Type II pattern, and modeling using the GAB model suggested stronger bonds in treatments with extended heating times. Despite the need for enhanced flexibility, the results indicate potential applications in snacks or as alternatives to nori. Notably, these films were produced solely with seaweeds and water, aligning with Nori's minimalistic approach. Treatments with a concentration of 60% U. lactuca and 40% K. alvarezii proved to be the most promising. This study lays the groundwork for future research in developing edible films derived from seaweeds. [ABSTRACT FROM AUTHOR]

The influence of different drying methods on the microstructure, porosity, and texture of pumpkins slices was assessed, aiming to find the best process conditions. Pumpkins ( Cucurbita moschata ) were selected, peeled, sliced, blanched and dehydrated by different methods: i) microwave multi-flash drying ( MWMFD ), ii) microwave vacuum drying ( MWVD ), iii) conductive multi-flash drying ( KMFD ), iv) freeze-drying ( FD ), and v) air-drying ( AD ). Micrographs of dried samples showed the compacted structure of AD samples and the spongy structure of FD samples. Otherwise, large pores and a highly porous structure were observed in samples dried by KMFD , MWVD , and MWMV . Porosity MWMFD samples were 2.6 times higher than those observed in AD pumpkins and slightly higher than the observed in FD samples. Puncture test results from KMFD , MWVD and MWMFD samples showed force oscillation that is typical of crispy products, which was not observed from AD and FD samples. Moreover, KMFD , MWVD , and MWMFD samples showed low color changes. Thus, microwave under vacuum and both multi-flash drying processes result in dried-and-crisp pumpkins, with high porosity and big pores. Therefore, these drying processes are suitable for the production of dried-and-crisp pumpkins. [ABSTRACT FROM AUTHOR]

In this study, the effect of different drying methods on the drying kinetics, product structures, rehydration kinetics and rehydration indices of dehydrated pumpkin slices was evaluated. For that, pumpkin slices were dehydrated by five different methods: i) Microwave multi-flash drying (MWMFD), ii) Microwave vacuum drying (MWVD), iii) Conductive multi-flash drying (KMFD), iv) Freeze-drying (FD), and v) Air-drying (AD). For reaching a moisture content of 0.022 g g −1 (dry basis, db) and water activity of 0.438, the drying times were 1.28 h for MWVD, 1.32 h for MWMFD, 3.50 h for KMFD, 16.33 h for AD and 16.67 h for FD. All the drying methods presented a constant drying rate period and a falling rate period. The highest constant drying rate was observed for MWVD, which was 1.3, 8, 22 and 53 times higher than the observed for MWMFD, KMFD, AD, and FD, respectively . Stereo micrographs of samples from multi-flash drying processes (KMFD and MWMFD) and from MWVD showed large pores in a highly porous structure. Rehydration of dried pumpkin slices was studied at 25 °C and 80 °C. Water temperature influenced samples rehydration ratio ( RR  = mass of rehydrated sample/mass of dried sample). RR up to 15 was observed at 25 °C, while RR up to 12 was observed at 80 °C. Samples from MWMFD and MWVD, rehydrated at 25 °C presented higher moisture after rehydration than those observed from AD, FD and KMFD samples. At 80 °C, FD samples showed the highest RR . From the whole results, one can conclude that MWVD and MWMFD are the suitable processes for producing dehydrated pumpkin slices in very short drying times. [ABSTRACT FROM AUTHOR]

Summary: In this work, the addition of pretreated Kappaphycus alvarezii flour to a rice‐based snack formulation was proposed as an alternative to producing algae‐enriched snacks adding value to this seaweed and improving the quality of the snacks. Dried algae were submitted to multiple washing cycles to allow the reduction of the natural salt concentration of the algae. After, algae were dried and milled to obtain flour. The flour was added in different concentrations (0%, 2%, 5%, and 10%) in the model formulation of rice‐based dough. Rice‐K. alvarezii snacks were produced by baking at 220 °C. The proximate composition of the raw and pretreated algae was determined, as well as the colour, texture, and microstructure of dough and snacks. The pretreatment efficiently allowed for a reduction of 78% of the initial content of sodium and an 85% reduction of potassium. The concentration of 5% and 10% of algae addition presented higher values of hardness and consistency of the dough and lower adhesiveness. At higher concentrations, the seaweed flour acts as a processing aid during the preparation steps of the snacks but does not influence the hardness of the final snacks. The pretreated K. alvarezii flour is an alternative for increasing the quality of rice‐based snacks while preserving the algae's potential health benefits. [ABSTRACT FROM AUTHOR]

Conductive multi-flash drying (KMFD) is an innovative drying process based on the application of multiple cycles of heating-vacuum pulse to a food to be dried. This method allows obtaining crispy-and-dried products with appealing characteristics. The objective of this study was to compare different drying methods (KMFD, air-drying, vacuum drying and freeze-drying) with respect to drying kinetics and physical properties of dried mangoes (porosity, microstructure, color, and mechanical properties). The influence of these drying methods on carotenoids concentration and rehydration were also investigated. Mango samples were dried from 5.30 g/g moisture (dry base) to 0.01 g/g (a w = 0.293) in 2.25 h by the KMFD, which was much shorter than the drying times observed for freeze-drying (16 h), air-drying (12 h) and vacuum drying (8 h). Porosity and texture of samples dried by KMFD were similar to the observed for freeze-dried samples, despite the different microstructures. Carotenoids concentration of freeze-dried samples was 1.6 times higher than that from KMFD, which was in turn 1.27 times higher than that from air-dried samples. KMFD is a new and innovative drying process that allows the production of crispy mangoes in reduced drying times, with carotenoids contents and rehydration ability similar to freeze-dried samples. [ABSTRACT FROM AUTHOR]

Peridinin is a light-harvesting carotenoid present in phototrophic dinoflagellates and has great potential for new drug applications and cosmetics development. Herein, the effects of irradiance mediated by light-emitting diodes on growth performance, carotenoid and fatty acid profiles, and antioxidant activity of the endosymbiotic dinoflagellate Durusdinium glynnii were investigated. The results demonstrate that D. glynnii is particularly well adapted to low-light conditions; however, it can be high-light-tolerant. In contrast to other light-harvesting carotenoids, the peridinin accumulation in D. glynnii occurred during high-light exposure. The peridinin to chlorophyll-a ratio varied as a function of irradiance, while the peridinin to total carotenoids ratio remained stable. Under optimal irradiance for growth, there was a peak in docosahexaenoic acid (DHA) bioaccumulation. This study contributes to the understanding of the photoprotective role of peridinin in endosymbiont dinoflagellates and highlights the antioxidant activity of peridinin-rich extracts. Key Points: • Peridinin has a protective role against chlorophyll photo-oxidation • High light conditions induce cellular peridinin accumulation • D. glynnii accumulates high amounts of DHA under optimal light supply [ABSTRACT FROM AUTHOR]

Algae are aquatic organisms rich in several biocompounds, and major ones are proteins and amino acids, carbohydrates and polysaccharides, lipids and fatty acids, pigments like chlorophyll, carotenoid, and phycocyanin, vitamins, minerals, and polyphenols that exhibit multiple beneficial effects on human health. These compounds are present in high concentrations in raw algal biomass, but some of them may not be available to exert their biological function in the human body, due to the inherent composition of algae cell wall. This review provides an overview of existing information of ongoing studies on the digestibility and bioavailability of algae derived compounds, while giving a glimpse of the studies that examine in vivo digestibility and bioaccessibility of microalgal biomass as feed supplementation for animals. Special attention is also given to the influence of cell wall disruption techniques on the bioaccessibility of algal bioactive compounds, showcasing carefully the in vitro bioaccessible nutrients of foods enriched with algal biomass. Digestibility and bioaccessibility of major compounds varied greatly between algal species. Polysaccharides and fibers are undigestible by humans, binding carbohydrates assimilation. Combined disruption methods like bead milling or high pressure homogenization with enzymatic pretreatment, using cellulases prior to algal compound extraction, may help to increase the extractability and bioavailability of lipid and fatty acids, pigments and minerals, as well as enhancing even further protein and amino acid absorptions. Studies on in vivo dietary supplementation of algae in animals (sheep, chicken, mice, and fishes) showed good acceptability and digestibility of proteins and lipids. Traditional foods such as cookies, snack, bread, and yogurt enriched with maximum 5% of algal biomass allowed to carry on natural bioactive compounds of algae, extending the bioaccessibility and enlightening the positive impact of consuming algae-based food for human health promotion. [Display omitted] • Algae as source of biocompounds for human health promotion. • Digestibility of seaweed and microalgae biomass is discussed. • Bioaccessibility of algal compounds is reviewed in detail. • Traditional foods enriched with algae and their digestibility are exemplified. • Cell disruption can increase the extractability of compounds, enhancing bioavailability. [ABSTRACT FROM AUTHOR]

This study aimed to obtain and characterize dehydrated chickpea snacks by sequential hydration, cooking, and drying processes. Hydration was performed at 4, 25, and 60 °C until reaching the maximum water uptake by the grains. Then, they were boiled until 80% of the grains reached firmness minor than 15 N. Cooked chickpeas were peeled and dried by three methods, air-drying (AD), freeze-drying (FD), and microwave multi-flash drying (MWMFD). The grains moisture was reduced from 1.681 ± 0.076 g/g to less than 0.050 ± 0.003 g/g and a w below 0.270. The constant drying rate was observed for all the three drying processes, followed by a falling drying rate period. MWMFD required a much shorter processing time (0.4 h) when compared to AD (10 h) and FD (15 h). The microstructure, and texture of the product were determined. Freeze-dried chickpeas were 1.2 and 2 times more porous than the MWMFD and AD samples, respectively. Micrographs showed small and uniform pores in FD samples, while MWMFD and AD samples had irregular porous matrix. MWMFD and AD samples exhibit jagged strain-force curves, characteristic of crispy foods. Therefore, MWMFD is a suitable process to obtain crispy chickpeas in short time. • Evolution of moisture vs bulk volume, determined during hydration, presents a linear behavior. • Peleg's and Fick's models fit well to bulk volume and moisture during hydration. • Hydration temperature did not influence physical properties and cooking behavior. • Density, porosity, and pore size are strongly influenced by the drying method. • Microwave multi-flash drying is 20-times faster than the other drying processes tested. [ABSTRACT FROM AUTHOR]

Banana slices were dehydrated by Conductive Multi-Flash Drying (KMFD) and stored at different relative humidities. A sensory panel determined the bananas' crispness and PCA correlated these results to mechanical and acoustic properties from compression and puncture tests. The BET model predicted the monolayer moisture as 0.0723 g/g with a w 0.388 as a supposed condition for good storage stability. However, based on crispiness, the sensory panel suggests a critical a w between 0.225 and 0.327. In the Spectrum crispness scale (intensity 0 to 15), the trained panel rated samples at a w 0.035 to 0.529 from 9.06 to 0.12, respectively. The number of acoustic peaks for the SPL bands depended on type and speed of the mechanical test. In compression, the parameters that correlated well to sensory crispness were moisture, number of force peaks, linear distance, and all acoustic parameters, independently of the acoustic filter (Arimi or FIR). In puncture test, the number of acoustic peaks highly correlated with sensory crispness. The striking correlation between the mechano-acoustic analyses and the sensory panel allows the reliable use of instrumental analyses in predicting the banana snacks crispness at different a w. It directly applies to industrial quality control since instrumental analyses are cheaper and faster than sensory panels. • – Banana snacks produced by Conductive Multi-Flash Drying. • – Dependence of crispness and aw of dehydrated bananas. • – Mechanical, acoustical, and sensory evaluation of banana snacks. • – Banana snack with aw higher than 0.32 loose crispness. • – Compression test showed a higher explanation of variables in PCA with two factors. [ABSTRACT FROM AUTHOR]

• Products from Spectrum Crispness Scale characterized by instrumental measurements. • SPLeq showed the highest linear correlation with the Spectrum Crispness Scale. • Penetration test was better than compression test to differentiate the products. • Poor correlation between sensory crispness and mechanical parameters were found. Mechanical and acoustical instrumental tests can help to predict and compare the sensory crispness of food products. This study proposed a method to correlate crispness sensory analyses to instrumental parameters using the standard products of the Spectrum Crispness Sensory Scale. An acoustic system was developed with a high-sampling rate for characterizing food crispness. Force-displacement and acoustic signals were measured during penetration and compression tests of the products in the Spectrum Scale. A band-pass filter suppressed the texture analyzer's engine and gearbox noise. High correlations were obtained between acoustical and sensory parameters in both tests; however, the penetration test better differentiated the products. The high-sampling rate acoustical measurement system was capable of discriminate crispy products, although the trained sensory panel was still more sensitive to small differences. [ABSTRACT FROM AUTHOR]