Retention Of Bioactive Compounds Research Articles

Enhancing Energy Efficiency and Retention of Bioactive Compounds in Apple Drying: Comparative Analysis of Combined Hot Air–Infrared Drying Strategies

The drying process is one of the oldest methods used to obtain food products that could be stored for a long time. However, drying is an energy-intensive process. Additionally, convective drying, due to the high temperature used during the process, results in loss in bioactive substances as well as nutritional value. Thus, in this research, apple slices were dried in a combined hot air–infrared air dryer with four different drying strategies and drying kinetics, internal and external mass transfer (Crank and Dincer models), and then the energy parameters were investigated. The first, second, third, and fourth strategies, respectively, include one-stage drying with a hot air (HA) or infrared energy source (IR), one stage but with two sources of hot air and infrared (HA–IR), and then there are two stages of first hot air and then infrared drying (HA+IR) and vice versa (IR+HA). According to the results, the highest effective moisture diffusion coefficient of the two Crank and Dincer models was equal to 1.49 × 10−9 and 1.55 × 10−8 m2/s, obtained in the HA70–IR750, and the lowest effective moisture diffusion coefficient was equal to 1.8 × 10−10 and 2.54 × 10−9 m2/s, obtained in IR250+HA40. The maximum (10.25%) and minimum (3.61%) energy efficiency were in the IR750 and HA55–IR250 methods, respectively. Moreover, the highest drying efficiency (12.71%) and the lowest drying efficiency (4.19%) were obtained in HA70+IR500 and HA40–IR250, respectively. The value of specific energy consumption was 15.42–51.03 (kWh/kg), the diffusion activation energy was 18.43–35.43 (kJ/mol), and the value of the specific moisture extraction rate (SMER) was in the range of 0.019–0.054 (kWh/kg). Compared to the other strategies, the second strategy (HA–IR) was better in terms of drying time and mass transfer, and the third strategy (HA+IR) was more efficient in terms of energy efficiency and drying efficiency. The infrared drying in the first strategy was better than that in the other methods in the other strategies in terms of retention of bioactive compounds.

Effect of Biopolymer Dip-Coating Pretreatments as a Non-Thermal Green Technology on Physicochemical Characteristics, Drying, and Rehydration Kinetics of Santa Maria Pears

This research was conducted to determine the influences of biopolymer dip-coating pretreatments as a non-thermal green technology on the drying behavior, retention of bioactive compounds, and quality properties of pears. The fresh pears were washed, peeled, and diced into cubes of 5 × 5 mm with a 2 mm thickness and were dipped into 0.3% (w/v) solutions of sodium alginate (SA), pectin (PC), xanthan gum (XG), Arabic gum (AG), and gelatin (GE) before hot air drying (70 °C, 2.0 m/s). The weight loss of samples during drying was recorded online, and the moisture ratio (MR) and drying rate were plotted against drying time. Biopolymers significantly decreased the drying time (maximum 33.33% by SA) compared with uncoated samples except for XG. Moisture diffusion coefficients were determined according to Fick’s second law of diffusion by plotting LnMR against drying time, and a linear regression analysis was applied to the data for the determination of moisture diffusion coefficients which ranged from 2.332 to 3.256 × 10−9 m2/s. The molecular transport of momentum, heat, and mass were determined from Newton’s law of viscosity, Fourier’s law, and Fick’s law, respectively. The results indicated that the friction drag force, convective heat, and mass transfer coefficients were 6.104 × 10−6 N, 76.55 W/m2·K, and 0.0636 m/s, respectively. Mathematical modeling showed the suitability of the Midilli and Kucuk and the Peleg models for the prediction of drying and rehydration processes, respectively. Thermal conductivity, specific heat, and density of coated samples ranged from 0.559–0.579 (W/m·K), 3735–3859 (J/kg·K), and 850.90–883.26 (Kg/m3), respectively. The porosity was reduced due to the penetration of biopolymers into the cellular matrix of samples. The highest total polyphenol content and antioxidant activity belonged to the AG samples. The biopolymers covering the surface of samples produced a protection layer against the loss of bioactive compounds. Biopolymers can be successfully used as a non-thermal green process for improving the drying and quality characteristics of pears at the industrial level.

Wheat Roll Enhanced by Buckwheat Hull, a New Functional Food: Focus on the Retention of Bioactive Compounds.

Wheat roll enhanced by buckwheat hull was used as a model for determining the retention of bioactive compounds during technological steps. The research included analysis of the formation of Maillard reaction products (MRPs) and retention of bioactive compounds such as tocopherols, glutathione, or antioxidant capacity. About a 30% decrease in the content of available lysine in the roll was observed compared to the value obtained for fermented dough. Free FIC, FAST index, and browning index were highest for the final products. The increase of analyzed tocopherols (α-, β-,γ-, and δ-T) was noticed during the technological steps, with the highest values found for the roll with 3% of buckwheat hull. A significant reduction in GSH and GSSG content occurred during the baking process. The observed increase in the value of the antioxidant capacity after the baking process may be the result of the formation of new antioxidant compounds.

Stability of labile xanthones and dihydrochalcones in a ready-to-drink honeybush beverage during storage.

The shelf-life of a functional herbal tea-based beverage is important not only for consumer acceptability, but also for the retention of bioactive compounds. The present study aimed to clarify the role of common iced tea beverage ingredients (citric and ascorbic acids) on the shelf-life stability of an herbal tea-based beverage. A hot water extract of green Cyclopia subternata, also used as honeybush tea, was selected as the main ingredient because it provides different types of phenolic compounds associated with bioactive properties (i.e. xanthones, benzophenones, flavanones, flavones and dihydrochalcones). The model solutions were stored for 180 and 90 days at 25 and 40 °C, respectively. Changes in their volatile profiles and color were also quantified as they contribute to product quality. 3',5'-Di-β-d-glucopyranosyl-3-hydroxyphloretin (HPDG; dihydrochalcone) and, to a lesser extent, mangiferin (xanthone), were the most labile compounds. Both compounds were thus identified as critical quality indicators to determine shelf-life. The stability-enhancing activity of the acids depended on the compound; ascorbic acid and citric acid enhanced the stability of HPDG and mangiferin, respectively. However, when considering all the major phenolic compounds, the base solution without acids was the most stable. This was also observed for the color and major volatile aroma-active compounds [α-terpineol, (E)-β-damascenone, 1-p-menthen-9-al and trans-ocimenol]. The addition of acids, added for stability and taste in ready-to-drink iced tea beverages, could thus have unwanted consequences in that they could accelerate compositional changes and shorten the shelf-life of polyphenol-rich herbal tea beverages. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Effect of Ferulic Acid and Its Derivatives on Cold-Pressed Flaxseed Oil Oxidative Stability and Bioactive Compounds Retention during Oxidation

Ferulic acid (FA) is a naturally occurring phenolic antioxidant that is widely used in the food, pharmaceutical, and cosmetic industries due to its low toxicity. Its derivatives also find numerous industrial applications and may have even higher biological activity than ferulic acid. In this study, the effect of the addition of FA and its derivatives-including vanillic acid (VA), dihydroferulic acid (DHFA), and 4-vinylguaiacol (4-VG)-on the oxidative stability of cold-pressed flaxseed oil and the degradation of bioactive compounds during oxidation was investigated. The results showed that FA and its derivatives affected the oxidative stability of flaxseed oil, but their antioxidant activity depended on the concentration (25-200 mg/100 g oil) and temperature of treatment (60-110 °C). Based on Rancimat test results, flaxseed oil oxidative stability predicted at 20 °C increased linearly with ferulic acid concentration, while its derivatives effectively prolonged the induction time at lower concentrations (50-100 mg/100 g oil). The addition of phenolic antioxidants (80 mg/100 g) generally showed a protective effect against polyunsaturated fatty acids (DHFA and 4-VG), sterols (4-VG), tocols (DHFA), squalene, and carotenoids (FA). The exception was VA, which increased the degradation of most bioactive compounds. It is believed that adding properly composed mixtures of FA and its derivatives (DHFA and 4-VG) can extend the shelf life of flaxseed oil and provide nutritional benefits.

Application of Electric Field Technologies in the Manufacture of Food Powders and the Retention of Bioactive Compounds

Electric fields have been used in the manufacturing of powders in a number of ways, including to enhance drying rates and retain heat-sensitive materials. Electrohydrodynamic drying and electrostatic spray drying use electric fields to accelerate the evaporation of liquid from a surface, resulting in faster drying times and improved product quality. These technologies are used in the food and pharmaceutical industries to manufacture powders from liquid feed materials. In addition to enhancing drying rates, the use of electric fields in powder manufacturing can also help to retain the bioactivity of compounds in the final product. Many bioactive compounds are sensitive to heat and can be degraded or destroyed during conventional drying processes. By using electric fields to dry powders, it is possible to reduce the amount of heat applied and therefore preserve the bioactive compounds in the final product. This article reviews the different mechanisms of various electric field assisted technologies, i.e., electrohydrodynamic atomization, electrohydrodynamic drying, pulsed electric fields and a new approach of electrostatic spray drying, along with their potential food industry applications.

Degradation kinetics of bioactive compounds in dried mistletoe leaves during storage

This work evaluated the effect of air atmosphere packaging and modified atmosphere packaging on the quality and nutritional compounds of dried mistletoe leaves during 4 months of storage at 4 and 25 °C temperatures. Mistletoe leaves packaged with modified atmosphere had improved nutritional qualities overall as compared to mistletoe leaves packaged with atmosphere air. At the end of the storage period, water activity values of all samples increased by 0.72%–3.38%. Before storage, the dried mistletoe leaves' total phenolic content was determined to be 301.73 ± 2.49 mg GAE/100 g dry matter. The total phenolic content of the samples decreased by 62.00%–71.96% after four months of storage. It was determined that the highest loss of total phenolic content was observed at room temperature (25 °C) and in the samples packaged with normal atmospheric air. Total antioxidant activity values in MAP2 samples decreased by 23.82% after four months when kept at low temperatures, but the loss was calculated to be 34.48% in cases where they were kept at room temperature. Ascorbic acid content losses in AP, MAP1, and MAP2 samples kept at room temperature were 21.48%, 15.90%, and 14.72%, respectively. In the samples stored at low temperatures, these loss rates were calculated as 16.62%, 13.05%, and 12.05%, respectively. No single model was satisfactory for describing changes in ascorbic acid content, which could not be determined in the samples stored at both 4 °C and 25 °C. The dried mistletoe leaves modified atmosphere packed and stored at low temperatures provided the highest bioactive compound retention.

Effectiveness of Opuntia ficus-indica mucilage as a carrier agent in microencapsulation of bioactive compounds of Amaranthus hypochondriacus var. Nutrisol

The effectiveness of maltodextrin (10%) and cactus mucilage (CM) (0%, 0.25%, 0.50%, 0.75%, and 1%) as carrier agents was evaluated in the encapsulation of bioactive amaranth compounds. Spray drying, an efficient encapsulation method, achieved high yields (62.9%–68%). The increase in CM concentration significantly augmented the water absorption index (WAI), bulk density, and hygroscopicity of the encapsulated amaranth powders. Conversely, it significantly decreased the moisture content, water activity, and water solubility index (WSI). The glass transition temperatures (>40 °C), Hausner ratio (HR), and Carr's index (CI) values indicated the suitability of powders for handling and processing. Moreover, no cracks were observed in the microcapsules surface, which favoured the bioactive amaranth compounds retention and stability. Thus, low degradation rate constants and long half-life time values were determined for the encapsulated amaranth powders, indicative of its storage appropriateness. Incorporation of 0.75% CM was an efficient concentration to achieve high percentage retention of betacyanins (55.5%), betaxanthins (58%), total polyphenols (73.3%), amaranthine (56.8%), isoamaranthine (62.7%), individual polyphenols (44.6%–81%), and antioxidant activity (79.6%). These results demonstrated the efficiency of CM as an encapsulating agent in the food industry.

Effect of driving pressure and flux rate on red wine nanofiltration

Red wine contains many bioactive components, such as phenolics, which play a beneficial role on human health and also are responsible for important sensory qualities of wine. Membrane technology offers advantages compared to the conventional methods used for polyphenols extraction in terms of high recovery/removal efficiency, no phase transition and mild operating conditions. In this study, nanofiltration of the native Bulgarian red wine Mavrud was performed. The MaxiMem membrane filtration system employing the nanofiltration membrane Microdyn Nadir™ NP030 P (MWCO 500 Da) was used for this purpose. The effects of the operating parameters (transmembrane pressure and flow rate) on the retention of bioactive compounds in wine were investigated. The phenolic amount of the obtained wine after nanofiltration was evaluated and compared with the data of the original wine. It was found out that the examined nanofiltration membrane can be effectively used for concentration of phenolics in wine. Optimal results with 29 % concentration of the phenolics in the obtained wine were achieved applying two sets of pressure and flow rate, namely 40 bar and 1.2 L/min, and 30 bar and 3 L/min.

Identify Bioactive Components and Optimize Dehydration Characteristic of Drumstick in GC-MS and Principle Component Analysis by using Heat Pump-assisted Dehumidified Air Drying (HPD)

Background: Drumstick (Moringa oleifera Lam.) is a miracle plant because of its therapeutic and nutraceutical properties. The present work aims to study the optimization and quality attributes retention in drumstick through Heat Pump-assisted dehumidified air Dryer (HPD) because the conventional drying process takes more time and energy which also affect the product quality and safety. Methods: Dried drumstick powder was prepared by using fresh drumstick pieces, steam blanched for 2-5 min and then sulfated at 0.1% for 10 min. After that, the dehydration process was performed at different temperatures (45, 55 and 65°C) in an HPD drier. Result: HPD dried drumstick powder at 55°C was found maximum drying characteristics and higher retention of bioactive compounds with special reference to high powder recovery (97.22%), excellent flowability and better functional characteristics. The extract of fresh and HPD dried drumstick powder contained 50 major bioactive compounds such as 2,6-Dihydroxybenzoic acid 3TMS derivative, Butanal 2-ethyl-3-methyl-, etc, these bioactive compounds act as various nutraceuticals and therapeutic values.

Plant-based pecan nut cake beverage enrichment of phytochemicals and antioxidant properties using multi-stage block freeze concentration

Pecan nut (Carya illinoinensis) processing to obtain oil generates circa 37% of press cake, which is currently underutilized and primarily employed as animal feed. Due to its nutritional- and bioactive-rich composition, pecan nut cake (PNC) can be used as raw material for plant-based beverages, whose properties may be enhanced using a non-thermal technology based on block freeze concentration (BFC). The effect of five-stage BFC on total solids content (TSC), pH, color parameters, retention of phytochemicals, and the antioxidant activity (AA) of a pecan nut cake beverage (PNB) was assessed in this work. BFC afforded 98% (w/w) solids retention after three stages and 85% efficiency after four stages. The process also provided a 254% concentration factor in stage 5. In the last step, approximately a 64% increase in TSC and a slight decrease (7.3%) in pH compared to the control PNB was observed. In addition, total phenolic compounds, condensed tannins, total flavonols, and AA were significantly (P < 0.05) improved after the BFC, resulting in a 2.6-10.2- and 1.9-5.8-fold increase in phytochemicals and antioxidants, respectively. On the other hand, BFC caused the darkening of concentrates due to TSC and bioactive compounds retention. The processing strategy evaluated herein indicated a great potential of PNC as a raw material for obtaining high-quality ingredients for the food industry, which may reduce agro-industrial waste production and add value to a coproduct rich in nutrients and biocompounds with potential biological activity.Graphical

Effect of gum Arabic and ethanol pretreatments on drying kinetics and quality attributes of dried carrot slices

Carrot is an important root vegetable to the food industry and consumers due to its nutritional and health benefits. Given the high moisture content and low shelf life of fresh carrots, preserving this highly demanded vegetable is vital. This current research modelled the drying kinetics and evaluated the quality of ultrasonic-assisted gum Arabic and ethanol pretreated and oven-dried carrot slices. Fresh carrots were processed into thin slices and immersed in 3% gum Arabic (GA), ethanol (99.9%), and distilled water (control), followed by ultrasonication (frequency: 50 Hz, power: 500 W, temperature: 25 °C) for 10 min and drying in a hot air oven at 50 °C. The loss of moisture from the carrots was periodically recorded, converted to moisture ratio before fitted to eleven semi-theoretical thin layer drying mathematical models. The effects of the pretreatments on the retention of bioactive compounds and carrots' physical and chemical properties were also evaluated. From the tested models, the Diffusion, Modified Henderson and Pabis, and Two-term models showed the best fitting (R2 = 0.9944–0.9985; RSME = 0.0103–0.0227) to the experimental data from 3% GA and ethanol pretreated carrots, while control samples followed the Aghbasho model (R2 = 0.9999; RMSE = 0.0033). Overall, the 3% GA pretreated carrot slices exhibited better colour (yellowness: 25.82–34.50; total colour differences: 8.12–13.06), water activity (0.37–0.44), total phenolic content (1.34–2.99 mg GAE/100 g DM), β-carotene (7.63–13.07 mg/100 g DM), and DPPH radical scavenging activity (5.67–8.02 mM AAE/100 g DM) than ethanol pretreated carrot slices and control samples. At the same time, 3 % GA pretreatment did not affect the drying rate of the carrot slices. The total soluble solids/titratable acidity ratio, rehydration capacity, and shrinkage ratio did not significantly (p > 0.05) vary among the treatments. The findings of this study can be used to develop an optimal drying protocol for pretreated carrot slices and to produce shelf-stable carrot products that can be used dried, rehydrated, or in combination with other products.

Optimization of lyophilized microencapsulated phenolic extract concentration for enrichment of yoghurt and effect on chemical parameters, bioactive compounds, antioxidant activity and sensory quality under storage

• Lyophilized microencapsulated phenolics utilized for enrichment of yoghurt. • Sensory acceptability, bioactive and chemical characteristics were compared. • Higher bioactive compounds observed in enriched yoghurt than normal yoghurt. • 2% enriched yoghurt showed higher sensory acceptance besides higher bioactives. In this study lyophilized microencapsulated phenolic extract powder (MPE) from peel of wild pomegranate fruit was utilized for enrichment of yoghurt. From different treatments, treatment (T 4 ) enriched with 2(%) MPE was found best on the basis of sensorial attributes. The significant increase ( p < 0.05) in yoghurt bioactive compounds and various antioxidant properties were observed after incorporation of 2(%) MPE. Changes in various characteristics were recorded at different storage intervals (0, 7 and 14 days). After 14 days of storage enriched yogurt retained higher phenolics (96.52%), flavonoids (97.72%), radical scavenging activity (95.85%), metal chelating activity (96.53%), FRAP (96.22%) and reducing power (94.49%) besides higher colour scores and sensory acceptability. Hence yoghurt could also be kept safe for 14 days under refrigeration temperature (4–7 °C) conditions in polystyrene cups with minimum changes in quality attributes. This study suggests that functional and antioxidant properties of yoghurt can be enhanced significantly by MPE enrichment without sensorial alterations, with maximum retention of bioactive compounds, thus product could be utilized commercially. The study also concluded that enriched yoghurt had higher phenolics and antioxidant activity which could open a new way towards the consumption of functional food.

Effect of ultraviolet light-emitting diode processing on fruit and vegetable-based liquid foods: A review.

Ultraviolet light-emitting diode (UV-LED) technology has emerged as a non-thermal and non-chemical treatment for preserving liquid fruit and vegetable foods. This technology uses ultraviolet light to interact with the food at different wavelengths, solving problems related to product stability, quality, and safety during storage. UV-LED treatment has been shown to affect microbe and enzyme inactivation, and it increases and improves retention of bioactive compounds. Moreover, computational simulations are a powerful and relevant tool that can be used optimize and improve the UV-LED process. Currently, there are a limited studies of this technology in liquid fruit and vegetable-based foods. This review gathers information on these food type and shows that it is a promising technology for the development of new products, is environmentally friendly, and does not require the addition of chemicals nor heat. This is relevant from an industrial perspective because maintaining the nutritional and organoleptic properties ensures better quality. However, due to the scarce information available on this type of food, further studies are needed.

Hydrodynamic cavitation processing of ascorbic acid treated precooled sugarcane juice for physiochemical, bioactive, enzyme stability, and microbial safety

AbstractA hydrodynamic cavitation (HC) system (0.35 MPa) with a cooling arrangement was developed for the treatment of ascorbic acid (AA)‐treated sugarcane juice (AASCJ). The AASCJ was precooled to different temperatures (4, 17, and 30°C) and underwent HC processing for different durations (10, 20, 30, and 40 min). The quality parameters such as pH, total soluble solids, titratable acidity, polyphenol oxidase (PPO), peroxidase (POD) activity, viscosity, total color difference, microbial load, total phenolic, flavonoids, AA, and antioxidant activity were investigated. The processed AASCJ precooled to 4°C resulted in more than 90% retention in color, total phenolic content, flavonoid content, and antioxidant activity. The PPO and POD activities significantly reduced after HC treatment. A 3 log reduction in the microbial population was achieved during HC processing. The optimized condition for HC treatment of AASCJ was a precooling temperature of 4°C and a treatment time of 30 min.Practical applicationsSugarcane juice has a short shelf life due to the high rate of microbiological contamination and enzymatic reactions that occur shortly after extraction. Low‐temperature HC is a nonthermal approach for processing low viscous liquid foods. The HC processed AASCJ is microbiologically safe, with reduced PPO and POD activity, and better retention of bioactive compounds. The low‐temperature HC processing can be used instead of thermal processing to reduce both enzymatic and nonenzymatic browning reactions and eradicate pathogenic microorganisms while maintaining the sugarcane juice quality. This approach is simple to handle, requires little investment, and does not use environmentally hazardous chemicals.

The effect of drying methods on chlorophyll, polyphenol, flavonoids, phenolic compounds contents, color and sensory properties, and in vitro antioxidant and anti-diabetic activities of dried wild guava leaves

Wild guava (Psidium guajava L.) commonly grows in tropical forests, and its leaves have long been used by Asian ethnic minorities as herbal tea and traditional medicine. This study aimed to evaluate the effects of different drying methods (sun drying, hot air drying, microwave drying, vacuum drying, and freeze drying) on the retention of bioactive compounds, antioxidant, and antidiabetic activities of wild guava leaves collected in Vietnam. The results showed that drying methods significantly affected the retention of bioactive compounds, biological activities, and color of guava leaves. The freeze-dried leaves had the highest levels of total phenolic content (173.25 ± 0.68 mg gallic acid equivalent g−1 dw), total flavonoid content (24.46 ± 0.78 mg QE g−1 dw), antioxidant capacity, and in vitro antidiabetic activity compared with others, while sun-dried leaves showed the lowest values of those parameters. The principal component analysis (PCA) showed a strong correlation among biological activities and contents of bioactive compounds, including antioxidant activity, in vitro antidiabetic activity, total phenolic content, and total flavonoid content (r 2 = 0.999, p < 0.0001). Specifically, the biological activities strongly and positively correlated epicatechin, rutin, chlorogenic acid, catechin, and gallic acid. Freeze-dried guava leaves had the highest positive scores, followed by hot air-dried, microwave-dried, vacuum-dried, and sun-dried samples. FD treatment sample also exhibited better color and sensory properties than others. Consequently, freeze drying is recommended as the most suitable drying method for preserving the bioactive compounds and sensory characteristics of dried wild guava leaves.

Raspberry pulp pasteurization: Computational fluid dynamics modeling and experimental validation of color and bioactive compound retention

AbstractThis work evaluated the heat transfer, fluid flow, and different reactions that occur during the pasteurization of raspberry pulp. The pulp was packed in glass jars and thermal processing was conducted by immersion in a water bath. The process was evaluated by multiphysics modeling, with the aim of determining the temperature distribution, flow pattern, the slowest heating zone (SHZ) location, the microbial inactivation, and the quality changes taking place during processing. In order to simulate the process accurately, a model was developed using experimentally measured product and heat transfer properties (density, thermal expansion, specific heat, thermal conductivity, apparent viscosity, and convective heat transfer coefficient) and kinetics of thermal degradation of quality parameters (color, anthocyanin, and ascorbic acid). The model was successfully validated against experimental measurements of both temperature and quality losses. After validation, the model was used to design and evaluate equivalent thermal processing conditions. Improved processes were identified that minimized the changes of color and the bioactive compounds, while maintaining product safety and stability.Practical ApplicationsThermal processing of raspberries may induce several physicochemical changes that impair their sensorial properties, and may reduce the content of nutrients and bioactive compounds. Hence, the design and optimization of heat treatments is a key tool to guarantee safety while, at the same time, minimizing detrimental side effects which involve a loss of quality. In this investigation, we assessed the actual thermo‐physical properties of raspberry pulp and the system heat transfer coefficients. Then, we developed a CFD model to predict the temperature and velocity transient profiles, the location of the SHZ, and the quality changes occurring in raspberry pulp during pasteurization. The findings of this study could be useful to food processors for optimizing pasteurization conditions in order to obtain safe and high‐quality raspberry pulp preserves, as well as for reducing processing energy requirements.

Post‐harvest application of micellar pomegranate peel extract (MPPE) enriched starch‐casein composite coating to preserve the plum (Prunus salicina L.) fruit during cold and ambient storage

AbstractThe present investigation applied a new coating (taro starch‐casein composite enriched with micellar pomegranate peel extract (MPPE)) to mature plum (Prunus salicina L.) fruits in a randomized factorial design with five replicates. Results showed that, during storage of 20 days at 5 and 23°C, a recognizable reduction in weight and firmness loss with a stable respiration rate of coated plums than uncoated ones (4.5% and 8.4% at 5 and 23°C respectively) were noticed. The coating provided appealing optical properties with exceptionally controlled changes in pH and acidity of plums. The coating significantly reduced the change in total soluble solids (TSS) at the end of storage which was 9 and 11.67°brix compared to uncoated fruits (11.83 and 13.08°brix) at 5°C and 23°C, respectively. Moreover, the loss of bioactives (polyphenols, flavonoids, antioxidant capacity, and ascorbic acid) was arrested due to bioactive coating. A slight rise in total anthocyanins, carotenoids, and reducing sugars was observed at 23°C. However, they were efficiently suppressed in coated fruits stored at 5°C. Microbial growth was also effectively controlled in coated plum fruits. Overall, the results suggested that applying MPPE starch‐casein composite coating on plum fruits exhibited a noticeable shelf life of ≥20 and 14 days at 5 and 23°C, respectively, over uncoated fruits (about 12 and 8 days).Novelty impact statementPlum fruit is a nutritionally rich climacteric fruit. However, it is very prone to deterioration and thus a quick loss in its quality. Many postharvest practices, such as irradiation, controlled and modified atmosphere storage, and chemical and thermal treatment have been used. However, these methods affect the nutritional value of fruits. The biodegradable bioactive coating is one of the cost‐effective ways for the shelf‐life extension of fruits. In this regard, natural bioactive and antioxidant‐rich MPPE enriched starch‐casein composite acts as a barrier against moisture loss and gas exchange and provides a glossy appearance to the fruits. Moreover, the bioactive coating provides excellent pathogen resistance with effective retention of bioactive compounds. Using the finding of this study, the application of MPPE enriched starch‐casein composite coating to plum fruits stored at ambient (23°C) and cold (5°C) storage can extend the postharvest shelf‐life of plum, save cost and energy, and open the global marketing window for plum fruits. MPPE‐taro starch‐casein composite coating was successfully used to prolong the postharvest life of plum fruits as well as to minimize fruit processing industrial waste by utilizing pomegranate peel as a source of a bioactive ingredient. Physical (color, firmness, and weight loss), chemical (pH, acidity, and TSS), and bioactive (polyphenols, ascorbic acid, carotenoids, and anthocyanins) properties of plums were found to be retained with the application of coatings during storage. The composite coating containing natural bioactive compounds can be used as an effective alternative to synthetic preservatives with an eco‐friendly approach.

Hot-Air Flow Rolling Dry-Blanching Pretreatment Improves the Drying Quality of Acanthopanax sessiliflorus by Increasing the Drying Rate and Inactivating Enzymes

The processing of Acanthopanax sessiliflorus has attracted interest due to its health benefits. In this work, an emerging blanching technology, called hot-air flow rolling dry-blanching (HMRDB), was employed to treat A. sessiliflorus before drying. The effects of varied blanching times (2–8 min) on enzyme inactivation, drying characteristics, bioactive compound retention, and microstructure were examined. The results demonstrated that blanching for 8 min rendered polyphenol oxidase and peroxidase nearly inactive. The blanching process reduced the drying time of samples by up to 57.89% compared to an unblanched sample. The Logarithmic model showed good fitting performance for the drying curves. The total phenolic and flavonoid content of the dried product increased as blanching time increased. The total anthocyanin content of the samples blanched for 6 min was 3.9 times higher than that of the unblanched samples, and 8 min of blanching produced the greatest DPPH• and ABTS• scavenging capabilities. The retention of active compounds in a dried product is a result of the inactivation of enzymes and a reduced drying period. Changes in the porous structure of the blanched samples would be responsible for the accelerated drying rate, according to microstructural analysis. These results indicate that HMRDB enhances the drying process and improves drying quality when applied to A. sessiliflorus before drying.

Effect of sucrose on the extrusion of varied whole sorghum grits genotypes

AbstractThe effect of sucrose on the extrusion of varied whole sorghum genotypes was studied using a single‐screw system. The raw sorghum flours were characterized in terms of chemical composition and particle size. Specific mechanical energy (SME) was measured as a process parameter, as well as expansion properties, hydration, paste viscosity, instrumental color, and texture, along with total phenolic compounds (TPC) and total condensed tannins (TCT) in the puffed extrudates. In general, the addition of 10% sucrose reduced SME (p &lt; .05), sectional expansion, hydration, and cold paste viscosity, indicating lower starch conversion and increased lightness (L*) and hardness (Fc). In contrast, BRS 501 showed opposite results for most of the variables measured, due to the suppression of the lubricant effect attributed to the high lipid in this genotype. Furthermore, the extrusion process at 0% sucrose released TPC values by 71.2% and 317.5% for low‐tannin extrudates, while the addition of sucrose (10%) did not alter the TPC (p &gt; .05) and had a protective effect on TCT retention in BRS 305 genotype extrudates.Practical applicationsThe worldwide food intake of non‐traditional whole grains such as sorghum has been restricted. Although it has been recently considered as an interesting an attractive gluten‐free cereal due to its high and varied content of phytochemicals that provide health benefits and dietary fiber source. To take advantage of its potential, thermoplastic extrusion technology was used as a tool to develop textured sorghum expanded products with improved digestibility and retention of bioactive compounds. On the other hand, in order to improve its potential use as sweet snacks, the addition of sugar concentrations (10%) was added to improve its palatability, allowing to obtain expanded extrudates rich in fiber and bioactive compounds with improved taste compared to conventional extrudates, which would be of interest of the consumer and the food industries.