Impact of Drying Methods on Phenolic Components and Antioxidant Activity of Sea Buckthorn (Hippophae rhamnoides L.) Berries from Different Varieties in China

Sea buckthorn berries are rich in bioactive compounds and can be used for medicine and food. The variety and drying method used have an important influence on quality. In this study, different sea buckthorn varieties from China were selected and dried with four common drying methods. The total phenolic content (TPC), total flavonoids content (TFC), contents of 12 phenolic compounds and antioxidant capacity in vitro were analyzed. The results showed that the TPC, TFC and antioxidant activity of two wild sea buckthorn berries were higher than those of three cultivated berries, and for the same varieties, measured chemical contents and antioxidant activity of the freeze-dried fruit were significantly higher than those obtained with three conventional drying methods. In addition, forty-one compounds in sea buckthorn berry were identified by UPLC-PDA-Q/TOF-MS, most of which were isorhamnetin derivatives. Multivariate statistical analysis revealed narcissin and isorhamnetin-3-O-glucoside varied significantly in sea buckthorn berries of different varieties and with different drying methods; they were potential quality markers. Strong correlations were found between TPC, gallic acid and antioxidant capacity (p < 0.05). The results revealed how components and antioxidant activity varied in different sea buckthorn, which provides a valuable reference for quality control and further development and utilization of sea buckthorn.     

Effect of Spray Dryer Scale Size on the Properties of Dried Beetroot Juice

Experiments detailing the spray drying of fruit and vegetable juices are necessary at the experimental scale in order to determine the optimum drying conditions and to select the most appropriate carriers and solution formulations for drying on the industrial scale. In this study, the spray-drying process of beetroot juice concentrate on a maltodextrin carrier was analyzed at different dryer scales: mini-laboratory (ML), semi-technical (ST), small industrial (SI), and large industrial (LI). Selected physicochemical properties of the beetroot powders that were obtained (size and microstructure of the powder particles, loose and tapped bulk density, powder flowability, moisture, water activity, violet betalain, and polyphenol content) and their drying efficiencies were determined. Spray drying with the same process parameters but at a larger scale makes it possible to obtain beetroot powders with a larger particle size, better flowability, a color that is more shifted towards red and blue, and a higher retention of violet betalain pigments and polyphenols. As the size of the spray dryer increases, the efficiency of the process expressed in powder yield also increases. To obtain a drying efficiency >90% on an industrial scale, process conditions should be selected to obtain an efficiency of a min. of 50% at the laboratory scale or 80% at the semi-technical scale. Designing the industrial process for spray dryers with a centrifugal atomization system is definitely more effective at the semi-technical scale with the same atomization system than it is at laboratory scale with a two-fluid nozzle.     

Quantification of Flavonoids,Phenols and Antioxidant Potential from Dropped Citrus reticulata Blanco Fruits Influenced by Drying Techniques

Physiologically dropped immature Citrus reticulata Blanco fruits are regarded as waste and discarded in the citrus orchard but are a good source of bioactive compounds including flavonoids, antioxidants and total phenols. A study was undertaken to identify and quantify these bioactive compounds and to investigate the influence of different drying techniques, namely freeze drying and hot air oven drying, on flavonoids namely flavanone glycosides, antioxidant potential and total phenol content in immature dropped fruits of Citrus reticulata Blanco. Flavonoids were quantified in high-performance liquid chromatography (HPLC). The antioxidant activity were investigated with three assays azino-bis [3-ethylbenzthiazoline-6-sulfonic acid]) (ABTS), 2,2-diphenyl-1-picrylhydrazyl radical (DPPH), Ferric Reducing Ability of Plasma (FRAP) and total phenol content was determined. Freeze dried samples of 12 and 14 mm size retained maximum hesperidin flavonoid content (27.03% and 27.20%) as compared to the hot air dried samples (17.99%) and retained higher phenolic content ranged from 50.54–54.19 mg GAEL⁻¹. The antioxidant activity in freeze dried fruits was from 12.21–13.55 mM L⁻¹ Trolox and 15.27–16.72 mM L⁻¹ Trolox with ABTS, DPPH assay and FRAP values ranging from 7.31–9.07 mM L⁻¹ Trolox. Significant positive correlation was found between the flavonoid hesperidin with antioxidant assays and total phenolic content (TPC). The results showed that waste citrus fruits can act as potential source of bioflavonoids, especially hesperidin, and antioxidants for pharmaceutical as well as nutraceutical industry.     

Influence of Freezing and Different Drying Methods on Volatile Profiles of Strawberry and Analysis of Volatile Compounds of Strawberry Commercial Jams

Strawberry is the most consumed berry fruit worldwide due to its unique aroma and flavor. Drying fruits to produce a powder represents one of the possible conservation methods to extend their shelf-life. The aim of the present study was to compare the influence of freezing and different drying methods on the volatile profile of strawberry using the HS-SPME/GC–MS method, in addition to analysis of strawberry jam volatiles. A total of 165 compounds were identified, accounting for 85.03–96.88% of the total volatile compositions. Results and PCA showed that freezing and each drying process affected the volatile profile in a different way, and the most remarkable representative differential volatiles were ethyl hexanoate, hexyl acetate, (E)-2-hexenyl acetate, mesifurane, (E)-nerolidol, γ-decalactone, 1-hexanol, and acetoin. Shade air-dried, frozen, freeze-dried, and oven-dried 45 °C samples retained more of the fruity and sweet aromas of strawberry, representing more than 68% of the total aroma intensity according to the literature. In contrast, the microwave-drying method showed drastic loss of fruity esters. Strawberry jams demonstrated complete destruction of esters and alcohols in most jams, while terpenes were significantly increased. These findings help better understand the aroma of strawberry and provide a guide for the effects of drying, freezing, and jam processing.     

Microwave-Assisted Extraction of Curcuma longa L. Oil: Optimization,Chemical Structure and Composition,Antioxidant Activity and Comparison with Conventional Soxhlet Extraction

Curcuma root (Curcuma longa L.) is a very important plant in gastronomy and medicine for its unique antiseptic, anti-inflammatory, antimicrobial and antioxidant properties. Conventional methods for the extraction of curcuma oil require long extraction times and high temperatures that can degrade the active substances. Therefore, the objectives of the present study were: (i) first, to optimize the extraction yield of curcuma oil by applying a Box-Behnken experimental design using surface response methodology to the microwave-assisted extraction (MAE) technique (the independent variables studied were reaction time (10–30 min), microwave power (150–200 W) and curcuma powder/ethanol ratio (1:5–1:20; w/v); and, (ii) second, to assess the total phenolic content (TPC) and their antioxidant activity of the oil (at the optimum conditions point) and compare with the conventional Soxhlet technique. The optimum conditions for the MAE were found to be 29.99 min, 160 W and 1:20 w/v to obtain an optimum yield of 10.32%. Interestingly, the oil extracted by microwave-assisted extraction showed higher TPC and better antioxidant properties than the oil extracted with conventional Soxhlet technique. Thus, it was demonstrated that the method applied for extraction influences the final properties of the extracted Curcuma longa L. oil.     

Physicochemical Properties and Antioxidant Activity of Spray-Dry Broccoli (Brassica oleracea var Italica) Stalk and Floret Juice Powders

This research presents the microencapsulation and conservation of antioxidants of broccoli juice processed by spray drying, and proposes the use of a by-product as a technological application. Broccoli juice (BJ) extracted from two sources, stalks and florets, was spray-dried employing maltodextrin (MX) as a carrier agent at concentrations of 5, 7.5, and 10%, and inlet temperatures of 150 and 220 °C. The total phenolic content (TPC), and antioxidant activity (AA) of the BJ-MX powders were determined together with the physicochemical characteristics, including particle morphology, microstructure, and thermal properties. Based on the TPC and AA, the optimal processing conditions found were 5% of MX and a drying temperature of 220 °C. However, the florets showed higher TPC, while stalks presented higher AA under those processing conditions. The particles exhibited micrometric sizes and a mixture of spherical-shape particles and pseudo-spherical particles. The diffractograms indicated an amorphous microstructure in all samples. The glass transition temperature (Tg) was determined in the range of 50 °C for the samples dried at 150 °C and 55 °C for those dried at 220 °C. This suggested that powders might be stored at temperatures below the Tg without presenting any loss of antioxidants.     

Early Optimization Stages of Agave lechuguilla Bagasse Processing toward Biorefinement: Drying Procedure and Enzymatic Hydrolysis for Flavonoid Extraction

Agave lechuguilla agro-waste is a promising renewable material for biorefining purposes. The procurement of added-value co-products, such as bioactive phytochemicals, is required to improve bioprocesses and promote the bio-based economy of the productive areas of Mexico. In this study, we aimed to evaluate the effect of post-harvest management and enzymatic pretreatment as the first stages of the A. lechuguilla valorization process. Four drying methods were compared, and enzymatic hydrolysis was optimized to obtain a flavonoid-enriched extract applying ultrasound-assisted extraction. In both experiments, the total phenolic (TPC) and flavonoid (TFC) contents, HPLC-UV flavonoid profiles, and radical scavenging capacity (DPPH) were considered as response variables. The results demonstrated that light exposure during the drying process particularly affected the flavonoid content, whereas oven-dehydration at 40 °C in the dark preserved the flavonoid diversity and antioxidant functionality of the extracts. Flavonoid glycoside recovery, particularly anthocyanidins, was 1.5–1.4-fold enhanced by enzymatic hydrolysis using the commercial mix Ultraflo© under optimized conditions (pH 4, 40 °C, 180 rpm, and 2.5 h) compared to the unpretreated biomass. The extraction of flavonoids from A. lechuguilla bagasse can be carried out using a scalable drying method and enzymatic pretreatment. This study confirmed the potential of this agro-waste as a source of marketable natural products.     

New Freeze-Dried Andean Blueberry Juice Powders for Potential Application as Functional Food Ingredients: Effect of Maltodextrin on Bioactive and Morphological Features

Andean blueberry (Vaccinium meridionale Swartz) fruits are an underutilized source of anthocyanins and other valuable bioactive phytochemicals. The purpose of this work was to obtain Andean blueberry juice powders via freeze-drying processing and evaluate the effect of maltodextrin as a drying aid on their physicochemical, technological, microstructural, and bioactive characteristics. Andean blueberry juices were mixed with variable proportions of maltodextrin (20–50%); freeze-dried; and characterized in terms of their tristimulus color, Fourier transform infrared spectra (FTIR), moisture content, water activity, morphology, water solubility, flow properties, total polyphenols and anthocyanins content, and DPPH^•-scavenging capacity. The powders obtained presented suitable characteristics in terms of their water activity (<0.5), solubility (>90%), and bioactive compound recovery (>70% for total phenolics, and >60% for total monomeric anthocyanins), with antioxidant activities up to 4 mg equivalent of gallic acid/g of dry matter. Although an increased content of maltodextrin resulted in lower concentrations of phytochemicals, as expected, it also favored an increased % recovery (over 90% of total phenolics at the highest maltodextrin proportion) and improved their flow properties. Freeze-dried juice powders are a potential alternative for the stabilization and value addition of this fruit as a new source of functionality for processed foods.     

Characterization of Food Packaging Films with Blackcurrant Fruit Waste as a Source of Antioxidant and Color Sensing Intelligent Material

Chitosan and pectin films were enriched with blackcurrant pomace powder (10 and 20% (w/w)), as bio-based material, to minimize food production losses and to increase the functional properties of produced films aimed at food coatings and wrappers. Water vapor permeability of active films increased up to 25%, moisture content for 27% in pectin-based ones, but water solubility was not significantly modified. Mechanical properties (tensile strength, elongation at break and Young’s modulus) were mainly decreased due to the residual insoluble particles present in blackcurrant waste. FTIR analysis showed no significant changes between the film samples. The degradation temperatures, determined by DSC, were reduced by 18 °C for chitosan-based samples and of 32 °C lower for the pectin-based samples with blackcurrant powder, indicating a disturbance in polymer stability. The antioxidant activity of active films was increased up to 30-fold. Lightness and redness of dry films significantly changed depending on the polymer type. Significant color changes, especially in chitosan film formulations, were observed after exposure to different pH buffers. This effect is further explored in formulations that were used as color change indicators for intelligent biopackaging.     

Influence of ethanol and ultrasound on drying,bioactive compounds,and antioxidant activity of strawberries (Fragaria × ananassa)

This study aimed to evaluate the use of ethanol (ET) and ultrasound (US) in convective drying of strawberry slices, as well as the effect on physicochemical, bioactive, and antioxidant parameters. For this, strawberry slices with a thickness of 0.005 m were pretreated with ET (in different volume fractions), US, and a combination of both. Drying kinetics were performed for control strawberry slices (without ET and US) and pretreated with 50% ethanol (ET50), 50% ethanol and ultrasonic (ET50US), 100% ethanol (ET100), and 100% ethanol and ultrasonic (ET100US) at a temperature of 60 °C. Empirical and diffusive models were fitted to the experimental data to describe the drying kinetics, and the fresh and dried slices were analyzed according to the parameters of water activity (aw), water content, total phenolic compounds (TPC), total anthocyanins (ATS), vitamin C and antioxidant activity (AA) (ABTS?+, DPPH?, and FRAP). The use of the ET100US combination provided an increase in the moisture transport process, higher drying rate, shorter process time (570 min), and reduction of a_w to a safe value (a_w <0.5), however, it sharply degraded the TPC, ATS, and AA. The ET50US pre-treatment even with a drying time of 690 min was the most efficient, since the values of TPC, ATS, and vitamin C suffered smaller reductions, where the AA varied in only 10.32%, 13.78% and 6.54% for the methods ABTS?+, DPPH?, and FRAP, respectively when compared to fresh strawberry. In this sense, it can be stated that the pre-treatment with 50% ethanol and ultrasound (ET50US) showed less reduction in the degradation of bioactive and antioxidant properties, and in the minimization of drying time for strawberry slices.     

Extraction of Phenolic Compounds from Fresh Apple Pomace by Different Non-Conventional Techniques

Red Delicious apple pomace was produced at laboratory scale with a domestic blender and different non-conventional extraction techniques were performed to isolate phenolic compounds, such as ultrasound-assisted extraction (UAE), ultraturrax extraction (UTE), accelerated solvent extraction (ASE) and pulsed electric field (PEF) extraction pre-treatment. Total phenolic content (TPC) was determined by Folin–Ciocalteu assay. Phloridzin, the main phenolic compound in apples, was determined by chromatographic analysis Q-TOF-LC/MS. The results obtained with these techniques were compared in order to identify the most efficient method to recover polyphenols. The highest value of TPC (1062.92 ± 59.80 µg GAE/g fresh apple pomace) was obtained when UAE was performed with EtOH:H₂O (50:50, v/v), while ASE with EtOH:H₂O (30:70, v/v) at 40 °C and 50% of flush was the most efficient technique in the recovery of phloridzin. The concentration of the main phenolic compounds ranged from 385.84 to 650.56 µg/g fresh apple pomace. The obtained results confirm that apple pomace represents an interesti-ng by-product, due to the presence of phenolic compounds. In particular, phloridzin could be considered a biomarker to determine the quality of numerous apple products. Therefore, this research could be a good starting point to develop a value-added product such as a functional food or nutraceutical.     

Effect of Encapsulated Beet Extracts (Beta vulgaris) Added to Yogurt on the Physicochemical Characteristics and Antioxidant Activity

Beet has been used as an ingredient for functional foods due to its high antioxidant activity, thanks to the betalains it contains. The effects of the addition of beet extract (liquid and lyophilized) on the physicochemical characteristics, color, antioxidant activity (AA), total betalains (TB), total polyphenols (TP), and total protein concentration (TPC) were evaluated on stirred yogurt. The treatments (T1-yogurt natural, T2-yogurt added with beet juice, T3-added extract of beet encapsulated with maltodextrin, and T4-yogurt added with extract of beet encapsulated with inulin) exhibited results with significant differences (p < 0.05). The highest TB content was observed in T2 (209.49 ± 14.91), followed by T3 (18.65 ± 1.01) and later T4 (12.96 ± 0.55). The highest AA was observed on T2 after 14 days (ABTS˙ 0.819 mM TE/100 g and DPPH˙ 0.343 mM TE/100 g), and the lowest was found on T1 at day 14 (ABTS˙ 0.526 mM TE/100 g and DPPH˙ 0.094 mM TE/100 g). A high content of TP was observed (7.13 to 9.79 mg GAE/g). The TPC varied between 11.38 to 12.56 µg/mL. The addition of beet extract significantly increased AA in yogurt, betalains being the main compounds responsible for that bioactivity.     

Sustainable Drying and Torrefaction Processes of Miscanthus for Use as a Pelletized Solid Biofuel and Biocarbon-Carrier for Fertilizers

Miscanthus is resistant to dry, frosty winters in Poland and most European Union countries. Miscanthus gives higher yields compared to native species. Farmers can produce Miscanthus pellets after drying it for their own heating purposes. From the third year, the most efficient plant development begins, resulting in a yield of 25–30 tons of dry matter from an area of 1 hectare. Laboratory scale tests were carried out on the processes of drying, compacting, and torrefaction of this biomass type. The analysis of the drying process was conducted at three temperature levels of the drying agent (60, 100, and 140 °C). Compaction on a hydraulic press was carried out in the pressure range characteristic of a pressure agglomeration (130.8–457.8 MPa) at different moisture contents of the raw material (0.5% and 10%). The main interest in this part was to assess the influence of drying temperature, moisture content, and compaction pressure on the specific densities (DE) and the mechanical durability of the pellets (DU). In the next step, laboratory analyses of the torrefaction process were carried out, initially using the Thermogravimetric Analysis TGA and Differential Scaning Calorimeter DSC techniques (to assess activation energy (EA)), followed by a flow reactor operating at five temperature levels (225, 250, 275, 300, and 525 °C). A SEM analysis of Miscanthus after torrefaction processes at three different temperatures was performed. Both the parameters of biochar (proximate and ultimate analysis) and the quality of the torgas (volatile organic content (VOC)) were analyzed. The results show that both drying temperature and moisture level will affect the quality of the pellets. Analysis of the torrefaction process shows clearly that the optimum process temperature would be around 300–340 °C from a mass loss ratio and economical perspective.     

Oleocanthal Quantification Using 1H NMR Spectroscopy and Polyphenols HPLC Analysis of Olive Oil from the Bianchera/Belica Cultivar

The cultivar Bianchera is an autochthonous variety from the eastern part of northern Italy, but it is also cultivated in the Slovenian and Croatian peninsula of Istria where it is named Belica (Slovenia) and Bjelica (Croatia). The properties of oleocanthal, a natural anti-inflammatory ibuprofen-like compound found in commercial monocultivar extra virgin olive oils, were determined by means of both quantitative ¹H NMR (qNMR) and HPLC analyses, where qNMR was identified as a rapid and reliable method for determining the oleocanthal content. The total phenolic content (TPC) was determined by means of the Folin–Ciocalteau method and the major phenols present in the olive oils were also quantified by means of HPLC analyses. All these analyses confirmed that the cultivar Bianchera was very rich in polyphenols and satisfied the health claim provided by the EU Commission Regulation on the polyphenols content of olive oils and their beneficial effects on human health.     

Polyphenols and Antioxidant Activity of Citrus Fiber/Blackberry Juice Complexes

The objective of this study was to investigate the use of citrus fiber as a carrier of blackberry juice polyphenols. For that purpose, freeze-dried complexes with blackberry juice and different amounts of citrus fiber (1%, 2% and 4%) were prepared. Complexes were evaluated spectrophotometrically for total polyphenols, proanthocyanidins and antioxidant activity. Analyses of individual polyphenols were performed using high-performance liquid chromatography. IR spectra were recorded to confirm encapsulation. All analyses were performed after preparation and after eight months of storage, in order to examine the stability of formed complexes. The obtained results indicated that increasing the amount of fiber led to a decrease in the concentration of polyphenols and the antioxidant activity of complexes. Cyanidin 3-glucoside was the prevalent anthocyanin in complexes (138.32–246.45 mg/100 g), while cyanidin 3-dioxalylglucoside was present at lower concentrations (22.19–31.45 mg/100 g). The other identified and quantified polyphenols were hesperidin (from citrus fiber), ellagic acid and quercetin (1317.59–1571.65 mg/100 g, 31.94–50.11 mg/100 g and 20.11–33.77 mg/100 g, respectively). Degradation of polyphenols occurred during storage. Results obtained in this study confirmed that citrus fiber could be used for the formulation of novel bioactive additives. Such additives could enhance the antioxidant potential of products to which they are added, such as baked goods, dairy, or fruit products.     

Flavonoid/Polyphenol Ratio in Mauritia flexuosa and Theobroma grandiflorum as an Indicator of Effective Antioxidant Action

Studies on polyphenols and flavonoids in natural products reveal benefits in the prevention of multiple diseases. Proper extraction, treatment of extracts, and quantification of polyphenols and flavonoids demand attention from the scientific community in order to report more specific biological action. Total polyphenol content (TPC) and total flavonoid content (TFC) (measured at three different times) of ethanol, methanol and acetone extracts of Mauritia flexuosa (aguaje) and Theobroma grandiflorum (copoazú) fresh pulp, from the Colombian Amazon region, were evaluated with the purpose of focusing in the polyphenol/flavonoid proportion and its effective antioxidant activity. This objective could help to explain specific flavonoid biological action based on higher flavonoid proportion rather than higher total polyphenol content. Differences in extracting solvents resulted in statistically significant different yields; the highest TPC was observed with acetone 70% in Mauritia flexuosa and ethanol 80% for T. grandiflorum. The best flavonoid/polyphenol ratio in M. flexuosa was about 1:2.4 and 1:12.8 in T. grandiflorum and the antioxidant efficacy was proportionally higher for flavonoids extracted from T. grandiflorum. HPLC analysis revealed 54 µg/g of the flavonoid kaempferol in M. Flexuosa and 29 µg/g in T. grandiflorum. Further studies evaluating this proportionality, in seeds or peel of fruits, as well as, other specific biological activities, could help to understand the detailed flavonoid action without focusing on the high total polyphenol content.     

Thermal stability of total phenolic compounds and antioxidant activities of jaboticaba peel: Effect of solvents and extraction methods

The objective was to evaluate the effect of temperature on the degradation of total phenolic compounds (TPC) and antioxidant activities (AA), in addition to the effects of solvents (water, ethanol and methanol) and methods of maceration and ultrasound in the extraction of polyphenols from the jaboticaba peel powder (JPP). The thermal stability of the TPC and AA (DPPH, FRAP and ABTS) from JPP at different temperatures (90, 110 and 130 °C) was monitored over time (0–360 min). The effect of solvents (water, ethanol and methanol) and methods of maceration and ultrasound on the extraction of polyphenols from JPP was also evaluated. The best conditions for extracting polyphenols were quantified by HPLC. After extraction, the morphology of the powders was evaluated by scanning electron microscopy (SEM). The study of thermal stability showed that the ABTS radical presented a lower stability with time when compared to the other radicals. In addition, it was observed that the thermal degradation of TPC at the studied temperatures and that there is a positive correlation between TPC and AA. In the ultrasonic extraction using ethanol and methanol in the mass ratio of JPP/volume of solvent 1:20, the maximum TPC amounts were obtained. In the analysis by HPLC, a content of gallic acid (16.28 mg L⁻¹) and hesperidin (9.26 mg L⁻¹) were found for ethanol and methanol, respectively. The SEM images indicated that the changes in the structure favored the formation of pores contributing to the solubilization of TPC and consequently AA.     

Microwave-Assisted Extraction of Phenolic Compounds from Spent Coffee Grounds. Process Optimization Applying Design of Experiments

In this study, sustainable technology microwave-assisted extraction (MAE) in association with green solvents was applied to recover phenolic compounds from spent coffee grounds (SCGs). A design of experiments (DOE) was used for process optimization. Initially, a 2⁴⁻¹ two level Fractional Factorial Design was used and ratios “solvent to solute” and “ethanol to water” were identified as the significant experimental factors. Consequently, Central Composite Design (CCD) was applied to analyze the effects of the significant variables on the response yield, total polyphenols content (TPC), and antioxidant activity (AA) by the DPPH assay method, and quadratic surfaces to optimize those responses were generated. The values of the significant factors of 16.7 (solvent/solute) and 68.9% (ethanol/water) were optimized simultaneously the yield (%) at 6.98 ± 0.27, TPC (mg GAE/g) at 117.7 ± 6.1, and AA (µmol TE/g) at 143.8 ± 8.6 and were in excellent agreement with those predicted from the CCD model. The variations of the compositions of the lipids, caffeine, pentacyclic diterpenes, and FAME as a function of the dominant factor % ethanol in the solvent mixture were analyzed by applying NMR and GC-FID, and the results obtained confirmed their determinative significance.     

Production of Coconut Protein Powder from Coconut Wet Processing Waste and its Characterization

Virgin coconut oil (VCO) has been gaining popularity in recent times. During its production, byproducts such as coconut skim milk and insoluble protein are obtained which are underutilized or thrown away to the environment at present. This study deals with utilization of these byproducts to obtain a value-added product, namely, coconut protein powder. When coconut milk was subjected to centrifugation, three phases, namely, fat phase (coconut cream), aqueous phase (coconut skim milk), and solid phase (insoluble protein) were obtained. The coconut skim milk and insoluble protein were mixed and homogenized before spray drying to obtain a dehydrated protein powder. The proximate analysis of the powder showed high protein content (33?% w/w) and low fat content (3?% w/w). Protein solubility was studied as a function of pH and ionic content of solvent. Functional properties such as water hydration capacity, fat absorption capacity, emulsifying properties, wettability, and dispersibility of coconut protein powder were evaluated along with morphological characterization, polyphenol content, and color analysis. Coconut protein powder has shown to have good emulsifying properties and hence has potential to find applications in emulsified foods. Sensory analysis showed high overall quality of the product, indicating that coconut protein powder could be a useful food ingredient.     

Characterization of Betabel Extract (Beta vulgaris) Encapsulated with Maltodextrin and Inulin

Betalains are powerful antioxidants contained in beets. These are divided into betacyanins (red-violet) and betaxanthins (yellow-orange), and they can be used as natural colorants in the food industry. The effects of freeze-drying pure beet juice (B) and the encapsulation of beet juice with a dextrose equivalent (DE) 10 maltodextrin (M) and agave inulin (I) as carrier agents were evaluated. The powders showed significant differences (p < 0.05) in all the variables analyzed: water absorption index (WAI), water solubility index (WSI), glass transition temperature (T_g), total betalains (TB), betacyanins (BC), betaxanthins (BX), total polyphenols (TP), antioxidant activity (AA, via 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)) (ABTS), and 2,2-diphenyl-1-picrylhydrazyl (DPPH)) and total protein concentration (TPC). The highest values of antioxidant activity were found in the non-encapsulated beet powder, followed by the powder encapsulated with maltodextrin and, to a lesser extent, the powder encapsulated with inulin. The glass transition temperature was 61.63 °C for M and 27.59 °C for I. However, for B it was less than 18.34 °C, which makes handling difficult. Encapsulation of beet extract with maltodextrin and inulin by lyophilization turned out to be an efficient method to increase solubility and diminish hygroscopicity.