Rheological, textural and spectral characteristics of sorbitol substituted mango jam

Research on the quantitative relationship of the viscosity reduction effect of large-ring cyclodextrin on potato starch during gelatinization process and mechanism analysis

Starch is extensively used across various fields due to its renewable properties and cost-effectiveness. Nonetheless, the high viscosity that arises from gelatinization poses challenges in the industrial usage of starch at high concentrations. Thus, it's crucial to explore techniques to lower the viscosity during gelatinization. In this study, large-ring cyclodextrins (LR-CDs) were synthesized from potato starch (PS) by using 4-α-glucanotransferase and then added to PS to alleviate the increased viscosity during gelatinization. The results from rapid viscosity analyzer (RVA) demonstrated that the inclusion of 5 % (w/w) LR-CDs markedly reduced the peak viscosity (PV) and final viscosity (FV) of PS by 49.85 % and 28.17 %. In addition, there was a quantitative relationship between PV and LR-CDs. The equation was fitted as y = 2530.73×e-x/2.48+1832.79, which provided a basis for the regulation of PS viscosity. The mechanism of LR-CDs reducing the viscosity of PS was also studied. The results showed that the addition of LR-CDs inhibited the gelatinization of PS by enhancing orderliness and limiting water absorption, resulting in a decrease in viscosity. This study provides a novel method for reducing the viscosity of starch, which is helpful for increasing its concentration and reducing energy consumption in industrial applications.

Application of xanthan and locust bean gum mix or sorbitol in the jelly formulation to improved jelly 3D printing using a fused deposition modeling printer

This study examined the impacts of applying a xanthan and locust bean gum mix or sorbitol to a jelly formulation on the rheological parameters necessary for 3D printing a jelly applying the fused deposition modeling method. A jelly formulation was fortified with a gum mix (xanthan gum:locust bean gum = 0.625:0.375) at 1% (w/w), or added with sorbitol instead of sugar. Both treatments increased the values of storage modulus and yield stress, related to fidelity and shape retention, and adding the gum mix, in particular, increased the gel strength. Applying these treatments to the formulation that lacks the rheological parameters and gel strength required for 3D printing changed those values in a direction fulfilling the material requirements. This research confirmed that the application of xanthan and locust bean gum mix or sorbitol could adjust the properties of materials used in 3D printing for improved printability.

Effects of Halogen Lamp and Traditional Sun Drying on the Volatile Compounds, Color Parameters, and Gel Texture of Gongliao Gelidium Seaweed

Traditionally, the processing of Gelidium seaweed into Gelidium jelly was very complicated, and involved repeated washing with water and sun drying for seven rounds. The seaweed, which is originally reddish-purple in color, turns yellow in color after the repeated washing and sun drying cycles. However, the sun drying process can only be used on sunny days. Therefore, this study evaluated an alternative method, halogen lamp drying, and compared the qualities of the product, Gelidium jelly, made using the halogen lamp drying and traditional sun drying methods. The properties investigated included the agar yield, gelling temperature, hardness, springiness, rheological parameters, sensory attributes, color, and volatile compounds. The results demonstrated that the halogen lamp drying method required 12 washing and drying cycles to achieve similar jelly properties to seven rounds of sun drying in the experimental conditions. Volatiles including heptanal, β-ionone, and (E)-2-decenal could be used as indicators to monitor the washing and drying processes. Halogen lamp drying could be an alternative processing method for seaweed drying, especially on rainy days.

Sonication results in variable quality and enhanced sensory attributes of Adajamir (Citrus assamensis) juice: A study on an underutilized fruit

Citrus assamensis, commonly known as Adajamir, is an underutilized fruit with distinctive sensory and nutritional properties. The limited amount of research on this particular citrus type was recognized as one of the research gaps for this study. The objective of this study was to evaluate and compare the impacts of sonication, pasteurization, and thermosonication techniques on the quality and sensory attributes of Adajamir juice. A randomized experimental design was used in the study, wherein the juice underwent three different treatments. The results indicate that there were no significant changes in pH or titratable acidity following all treatments. Yet, notable differences in juice color were observed. The use of sonication and thermosonication resulted in an increase in β-carotenoid levels. Additionally, total phenolic content and antioxidant activities were observed to increase. All three treatments led to a reduction in ascorbic acid levels relative to the control. However, the complete elimination of microbial growth was observed during the thermal treatment. Compared to other approaches, sonication has been shown to be notably more efficacious in enhancing both the flavor and aroma. Sonication has been observed to improve the perceived bitterness to a certain degree. These findings support the potential of sonication as an alternative preservation method for Adajamir juice, offering enhanced quality and sensory acceptance.

Rheological parameters of mixed Brazilian Cerrado fruits sugar-free preserves: the effect of body agents

The aim of this study was to evaluate the effect of the bodying agents (erythritol, sorbitol, xylitol, and polydextrose) and their mixtures on the preparation of mixed Brazilian Cerrado fruit preserves (marolo, soursop, and sweet passion fruit). Mixture design was used for product optimization and the preserves were evaluated by texture profile, stress relaxation test, and uniaxial compression test. The research data were analyzed using regression equations on SAS software. The results indicated that the rheological parameters were affected by the body agents. Erythritol should not be used as an isolated component because it provoked changes in the properties of the final product (harder and brittle preserves); xylitol and sorbitol made preserves more elastic, cohesive, and more fragile; and polydextrose showed a synergistic effect with erythritol for rupture deformation and lesser effects for hardness, adhesiveness, and gumminess.

Impact of Apricot Pulp Concentration on Cylindrical Gel 3D Printing

The process of 3D food printing is a rapidly growing field that involves the use of specialized 3D printers to produce food items with complex shapes and textures. This technology allows the creation of customized, nutritionally balanced meals on demand. The objective of this study was to evaluate the effect of apricot pulp content on printability. Additionally, the degradation of bioactive compounds of gels before and after printing was evaluated to analyze the effect of the process. For this proposal, physicochemical properties, extrudability, rheology, image analysis, Texture Profile Analysis (TPA), and bioactive compounds content were evaluated. The rheological parameters lead to higher mechanical strength and, thus, a decrease in elastic behavior before and after 3D printing as the pulp content increases. An increase in strength was observed when the pulp content increased; thus, sample gels with 70% apricot pulp were more rigid and presented better buildability (were more stable in their dimensions). On the other hand, a significant (p < 0.05) degradation of total carotenoid content after printing was observed in all samples. From the results obtained, it can be said that the gel with 70% apricot pulp food ink was the best sample in terms of printability and stability.

Anchote (Coccinia abyssinica [Lam.] Cogn.) powder, an underutilized indigenous crop, as a substitute to commercial pectin in the production of strawberry jam

The study investigated the potential of anchote (Coccinia abyssinica [Lam.] Cogn.) tuber powder as a substitute to commercial pectin. Mixture D-optimal design was used to generate 14 experimental runs using ranges: strawberry fruit (45–55%), sugar (43–53%), and anchote powder (0.75–1.75%). The effect of anchote powder on physicochemical and textural qualities of the jams was evaluated. The parameters measured include: moisture content (30.7–32.8%), total soluble solid (50.7–65.4 ºBrix), water activity (0.73–0.80), pH (2.93–3.13), titratable acidity (0.58–0.72%), gel strength (326.39–440.37 g mm), hardness (26.36–35.09 g), cohesiveness (0.89–0.94), energy of penetration (418.72–489.51 g s), adhesiveness (−25.38 to −103.79 g s) and stickiness (−13.78 to −29.22 g). The jam formulation J₁₃ (50% strawberry, 48.2% sugar, 1.33% anchote) was best performing. Numerical optimization showed the best combination of parameters at 52.4% strawberry, 46.0% sugar, 1.07% anchote. The jam formulated with anchote powder was comparable with the jam made using pectin.

Sugar and no sugar added fruit microalgae-enriched jams: a study about their physicochemical, rheological, and textural properties

Jams are preparations of fruits whose main preserving agent is sugar. Due to this, health concerns of consumers have resulted in a sugar reduction, and its replacement using alternative sweeteners and introducing new ingredients enhancing nutritional properties. In this study, four types of fruits jams (plum, strawberry, apple, and peach), with or without sugar, were prepared using two microalgae biomass, Arthrospira platensis (Spirulina) and Chlorella vulgaris, and Dunaliella salina extract as ingredients at different mix levels of concentrations, 0.10%–0.10%–0.05% respectively, for plum; 0.04%–0.00%–0.01 respectively, for strawberry; 0.06%–0.04%–0.00% respectively, for apple and 0.00%–0.01%–0.04% respectively, for peach. Physicochemical, rheological, and textural parameters were evaluated. Substitution of sugar/fructose syrup in the jam’s preparation caused changes in pH values, solid soluble content, and rheological and textural properties compared to sugar jams. Using sugar or sweeteners as isomalt, stevia and sucralose and microalgae biomass or extract showed significant changes in colour coordinates, however, these differences were not perceptible by the human eye. Jams containing microalgae biomass-extract showed higher G', G'', G*, and η* values than their corresponding control samples. All the jams presented weak-gel characteristics, distinguishing fruit jams. However, the results of weak-gel model analysis suggest that the influence of the different ingredients in the food system depends not only on their concentration but also on the interactions in the gel structure. Strawberry and apple jams showed no significant differences between microalgae biomass-extract samples and control samples, for both sugar and no sugar added jams being the best-obtained samples.

Thermosonication effect on bioactive compounds, enzymes activity, particle size, microbial load, and sensory properties of almond (Prunus dulcis) milk

The object of this research was to appraise the physicochemical characteristics of almond milk and consumer acceptability after the thermosonication (TS) processing. The almond milk was subjected to TS processing (frequency: 40 kHz; power: 600 W; Temperature: 30, 45, and 60 °C; Time: 10, 20, 30, and 40 min) and pasteurization (for 60 s at 90 °C). After treatments, all samples were analyzed for bioactive compounds, antioxidant activities, microbial, enzymatic, and sensory attributes. The results showed a non-significant difference in total soluble solids and pH while TS processing at 45 and 60 °C significantly increased the cloudiness, viscosity, browning index, and color properties. TS processing increased the bioavailability of total phenolic, flavonols, flavonoids, condensed tannin contents, and antioxidant activity as compared to untreated and pasteurized samples. TS processing also significantly reduced the particle size distribution through acoustic cavitation. Microbial inactivation with TS at 60 °C resulted in ≥ 5 log reduction oftotal plate count and ≥ 4 log reduction ofyeast & moldwas achieved. The highest inhibition of lipoxygenase (LOX) and peroxidase (POD) were observed at 60 °C for 30 min. Moreover, the best sensorial properties were observed after TS processing at 60 °C. Thus; TS processing can increase the almond milk quality and safety as a viable substitute for thermal processing.

Food Hydrocolloids from Butternut Squash (Cucurbita moschata) Peel: Rheological Properties and Their Use in Carica papaya Jam

Hydrocolloids are a class of functional ingredients that are widely used in the development of food structures. The hydrocolloids are mainly polysaccharides and some proteins that are applied in various food products. For this reason, natural sources that are friendly to the environment must be sought for their extraction. Therefore, this study aimed to extract hydrocolloids from butternut squash (Cucurbita moschata) peels-HBSP-and determine the proximal composition and rheological properties as well as their use effect in a microstructure product like fruit jam from Carica papaya. Hydrocolloids were obtained from butternut squash at pH 3, 7, and 10 and at different temperatures, presenting higher yield values at 80 °C with higher carbohydrate and protein contents and non-Newtonian flow behavior type shear-thinning. In order to analyze the influence of HBSP on the rheological properties of the microstructured product, the samples were employed as a partial substitute of pectin in C. papaya jam (CPJ), showing a positive effect on the jam matrix due to the addition of hydrocolloids. The physicochemical properties of jams did not present significant differences. CPJ presents non-Newtonian behavior type shear-thinning adjusting to the Herschel-Bulkley model. The dynamic viscoelastic rheological test characterized the jam as a gel-like state when the storage modulus values were higher than the loss modulus values in the frequency ranges studied. Regarding the addition of HBSP, this modified the color parameter, presenting a reddish color with an increase in tonality, and the sensory evaluation showed that the M3 sample was better than the other products, with a higher level of satisfaction. The obtained results show that butternut squash peel is suitable for the obtention of hydrocolloids, and they can be used as a raw material in the development and formulation of food products, as well as their byproducts can be used to solve problems with organic waste from the agroindustry in an environmentally friendly way.

Optimization of physicochemical, textural, and rheological properties of sour cherry jam containing stevioside by using response surface methodology

The response surface method (RSM) was used to produce sour cherry jam containing stevia sweetener with favorable physicochemical, textural, and rheological properties. The experiments were designed based on RSM using a central composite design (CCD) with three independent variables: sugar, pectin, and stevia. Sample processing was performed at five levels of sucrose (10%-50%), pectin (0.1%-0.5%), and stevia (0.2%-0.6%) at a constant fruit weight of 300 g. To evaluate the jam, the physicochemical, textural, and rheological properties of the jam were determined and optimized. The concentrations of sucrose, pectin, and stevia had a significant effect on the textural and rheological properties of the jam. The results showed that increasing the concentration of sucrose is the main factor in increasing the soluble solids and the total sugar content of the jam. Pectin had a positive effect on textural characteristics such as hardness and adhesiveness of the jam, while the cohesiveness of the jam decreased with increasing pectin. Herschel-Bulkley model was appropriate for describing the rheological behavior of the stable state of sour cherry jam containing stevia. Decreasing sucrose concentration is accompanied by a decrease in yield stress and consistency index of jam samples due to the TSS reduction. Pectin also had a positive effect on the amount of yield stress and consistency index. Dynamic rheological tests indicated that the sour cherry jam is a weak gel. The predominant viscose behavior and the formation of a dilute solution were evident in the samples with 10% and 20% sucrose concentrations. The most favorable condition for the production of the jam was obtained at a 36.5% sugar, 0.277% pectin, and stevia 0.30%.

Effect of thermosonication on quality attributes of hog plum (Spondias mombin L.) juice

The use of thermosonication (TS) technique to preserve the qualities of fruit juice as an alternative to conventional pasteurization has attracted research interest in recent times. In the present study, freshly prepared hog plum juice (control), and the juice samples subjected to pasteurization (90 °C for 60 s) and thermosonication (40 kHz, 400 W at 40, 50 and 60 °C each for 5, 10, 20 and 30 min) were each analyzed for physicochemical, bioactive, microbial and sensory properties. After treatment, no significant changes in pH, total soluble solids and titratable acidity were observed. Notably, TS at 40 and 50 °C significantly (p < 0.05) improved color parameters, cloudiness and browning index. Furthermore, thermosonication increased ascorbic acid (11.40-18.55%), total phenolic content (17.98-18.35%), carotenoids (2.19-4.30%), flavonoids (10-16%) and antioxidant activity (32.52-48.5%) relative to the control. Both treatments significantly reduced the microbial count to non-detectable level after processing, while sensory attributes slightly improved. However, TS treatment at 60 °C decreased most of the quality parameters. Results showed that TS can improve quality, safety and economic potential of hog plum juice as a feasible alternative to pasteurization.

Impact of sugar replacement by non-centrifugal sugar on physicochemical, antioxidant and sensory properties of strawberry and kiwifruit functional jams

Raw cane sugars have been claimed to be rich in natural phenolic compounds which, in contrast to refined sugar, may increase the nutritional value of foods and contribute to the development of healthier foods and diets. The use of non-refined cane sugars in food formulation seems an interesting option since they provide natural antioxidants with sucrose still being the major sugar present, minimizing the loss of technological properties. However, substitution of refined sugar could imply an undesired impact on physicochemical and sensory properties, conditioning consumer's acceptance. Functional jams (strawberry and kiwifruit) with a larger fruit to sugar ratio than conventional ones, in which white sugar was replaced by granulated jaggery (0, 15, 30, 45, 60 y 75 % w/w) were obtained. Impact of sugar replacement was assessed by evaluating physicochemical properties (moisture, water activity, pH, total soluble sugars, sugar profile (glucose, fructose, sucrose), and optical, rheological, mechanical and antioxidant properties). Sensory properties and microbiological stability were also determined. Jaggery improved the antioxidant properties of jams (total phenolic content, total flavonoid content, antiradical activity by the DPPH and ABTS methods), proportionally to the amount of cane sugar incorporated and more significantly in the case of kiwifruit. Other physicochemical properties were not significantly affected by jaggery, except for color. However, these differences were not crucial in the acceptability tests, since acceptance of jams containing jaggery was generally good, very good when intermediate replacement percentages were used. Conclusions of the present work suggest that granulated jaggery can be used to formulate sugar-rich food products such as jams in order to increase their nutritional value, with little impact on physicochemical properties and good consumer acceptance.

Green chemical mechanical polishing of sapphire wafers using a novel slurry

Toxic and corrosive solutions are widely used in the preparation of abrasives and chemical mechanical polishing (CMP) of sapphire wafers, resulting in potential environmental pollution. Developing a novel green CMP technique to achieve light-emitting diode sapphire wafers is a significant challenge. In this study, a novel green CMP slurry, consisting of silica, sorbitol, aminomethyl propanol, and deionized water was developed for sapphire wafers. After CMP, the sapphire wafers were cleaned with deionized water and dried with compressed air, which is a green process. After CMP, the surface roughness Ra of the sapphire wafer surface with an area of 5 × 5 μm2 was 0.098 nm, which is the lowest surface roughness reported to date for sapphire wafers. Tetrahydroxy-coordinated Al(OH)4- ions were produced in the alkaline CMP slurry, and chelation occurred between sorbitol and these ions. The proposed green CMP has potential applications in the semiconductor and microelectronics industries.

Three Types of Red Beetroot and Sour Cherry Based Marmalades with Enhanced Functional Properties

The importance of bioactive compounds such as betalains and anthocyanins was highlighted in the present study by the valorization of red beetroot and sour cherry as an attempt to develop healthy products. The aim of the study was to obtain and characterize three types of marmalade based on red beetroot, sour cherry and both in 1:1 combination, obtained by heating at 95 °C for 30 min. Changes in total phenolic content, total flavonoids, betalains, anthocyanins and antioxidant activity were evaluated before and after the thermal treatment. Several other analyses such as color, rheological and textural analyses and confocal laser microscopy were performed to provide further information about the quality of the added-value food products. A significant decrease of 34% in betalains content was registered in the red beetroot marmalade due to the chemical changes in bioactives induced by the temperature. A satisfactory ABTS radical scavenging activity of 8.12 ± 0.38 mMol Trolox/g dry weight (dw) was obtained for the red beetroot and sour cherry based marmalade. The gelled structure was validated by the rheological and textural characteristics. The results highlighted the potential use of red beetroot and sour cherry as food raw materials, due to their particular profile of bioactive compounds.

Development of a reduced-calorie high pressure processed sapodilla (Manilkara zapota L.) jam based on rheological, textural, and sensory properties

High pressure technology (400 MPa at 27 ± 1.5 °C for 10 min) was applied for the processing of jam, and target was the reduction (∼47%) of sugar requirement by using a fiber-rich fruit, that is, sapodilla. Different formulations of jam containing various combinations of pectin (0.5 to 5.0%), sugar (45 to 65%), and acid (0.5 to 1) were investigated for textural, rheological, and sensory properties of the pressure-processed jam. The textural parameters mainly hardness (varied 16 to 594 g force) of the jam samples were significantly (P < 0.01) affected by the formulation ingredients viz. sugar and pectin content. Also, an interaction effect (P < 0.01) of sugar and pectin was observed on the jam hardness. The rheological parameters (gel strength, K') also varied (1036 to 2852 Pa) with the change in total soluble solids (TSS) and pectin content. However, the samples having lower TSS content (e.g. 45%) and appropriate pectin content (4.0, 4.5, or 5.0%) were similar (P > 0.05) to the samples having higher TSS content (65%) and corresponding pectin level (0.5, 1.0, or 1.5%) based on the rheological properties. On the other hand, the samples with middle levels of pectin at the corresponding TSS level (45 to 65%) were highest (score of >6 on seven-point hedonic scale) and equally preferred (P > 0.05) by the sensory panelist based on overall acceptability calculated from the scores obtained for sensory attributes viz. color, aroma, sweetness, sourness, texture, and spreadability. Therefore, the jam formulation containing sapodilla pulp as a base material, TSS 45%, pectin 4.5%, and citric acid 0.5% was determined to be the preferred formulation for the production of reduced-calorie, pressure-processed jam based on its gel strength, overall acceptability, and storage stability. PRACTICAL APPLICATION: High-fiber fruit was used for the development of a reduced-calorie high pressure processed jam in this study. The inherited or externally added fiber can favor the reduction in sugar requirement of a food product particularly those processed by high pressure, leading to reduction in calories. The findings of this study can be used for the development of novel HPP products with functional properties.

Structural and sensory analysis of compositionally optimized apple jellies enriched with dietary fibre compared to commercial apple jams

The objective of this work was to optimize the formulation of apple jellies enriched with 3 g/100 g of dietary fibre and to compare them with commercial apple jams in terms of structural and organoleptic properties. With that aim, a fibre mix with one part of psyllium and three parts of other fibre variety (apple, bamboo or wheat) was added to apple jelly, and the rheological, mechanical and sensory properties, as well as colour and syneresis (water loss) of the samples at different storage times were studied, and compared to two commercial apple jams. Those properties did not suffer significant changes during 30 days of cold storage, meaning that the product was stable. The reduction of psyllium proportion in the fibre mix (from 1:1 to 1:3) reduced the gumminess of the fibre enriched jellies, keeping the syneresis at 0 g/100 g. The jelly enriched with apple and psyllium fibre was the most similar to commercial apple jams in terms of rheological and mechanical properties. Consumers acceptability of fibre enriched jellies was higher than 72%, being the jelly enriched with bamboo and psyllium fibre the closest to a commercial apple jam, which was the consumer's favourite.

Modeling the rheological properties of currant paste as a function of plasticizers concentration, storage temperature and time and process temperature

The steady and dynamic shear rheological properties of currant paste samples as a function of storage temperature (15, 25 and 35 °C) and time (180 days) and plasticizers content (water and/or glycerol) have been evaluated. Apparent viscosity (η_a) has been found to be significantly increased with prolonged storage, implying possible structural changes, and decreased with the increase in storage temperature and the addition of water or/and glycerol. Flow behavior index and consistency index were determined by fitting the resulting experimental data to a power law equation with high values of correlation coefficients (R² ≥ 0.912). Furthermore, the combined effect of storage temperature, time and plasticizers concentration on the apparent viscosity was described adequately by a proposed empirical model, with low standard relative errors (SRE ≤ 0.011). Additionally, the viscoelastic properties were significantly affected by all evaluated parameters in the same way as in apparent viscosity while both moduli (G' and G″) were modeled sufficiently (R² ≥ 0.884) as power functions of oscillatory frequency. The heat treatment (heating from 25 to 100 °C and cooling back with a rate of 10 °C/min) applied has proved sufficient to reverse the observed storage effects. Moreover, the modified Cox-Merz rule was satisfactorily applied to describe the correlation between the apparent viscosity and the complex viscosity.

Effects of Mixing Ratio and pH on the Electrostatic Interactions of Hydrolyzed Alaska Pollock Protein and κ-Carrageenan

In order to widen the application of Alaska Pollock salt-soluble protein and improve the properties of κ-carrageenan (KC), we evaluated whether the electrostatic interaction between KC and hydrolyzed protein (HP) improved the solubility of salt-soluble proteins and assessed acid hydrolysis-induced changes in the viscosity of KC. Moreover, we determined the effects of pH, KC, and HP mixing weight ratio (R, from 1:8 to 8:1) on the properties of mixtures. ζ-Potential results demonstrated that there were electrostatic interactions between KC and HP. Results of solution transmission and precipitation diagram analysis demonstrated that increasing the ratio of KC in KC-HP mixtures expanded the pH range of HP water solubility and prevented HP from precipitating, even at pH values around the pI. The highest viscosity of the solution measured by rheology analysis occurred at pH 3.5, and the ratio of KC:HP (R) was 1:1. These findings suggested that Alaska Pollock protein could be modified appropriately for use in acidic solutions and semisolid foods; moreover, KC-HPs have a potential application as thickeners in acid condition.

PRACTICAL APPLICATION

These findings suggested that Alaska Pollock protein could be modified appropriately for use in acidic solutions and semisolid foods and that KC-HP may have applications as a new acid thickener.

Lactose-crosslinked fish gelatin-based porous scaffolds embedded with tetrahydrocurcumin for cartilage regeneration

Tetrahydrocurcumin (THC) is one of the major colourless metabolites of curcumin and shows even greater pharmacological and physiological benefits. The aim of this work was the manufacturing of porous scaffolds as a carrier of THC under physiological conditions. Fish-derived gelatin scaffolds were prepared by freeze-drying by two solutions concentrations (2.5% and 4% w/v), cross-linked via addition of lactose and heat-treated at 105 °C. This cross-linking reaction resulted in more water resistant scaffolds with a water uptake capacity higher than 800%. Along with the cross-linking reaction, the gelatin concentration affected the scaffold morphology, as observed by scanning electron microscopy images, by obtaining a reduced porosity but larger pores sizes when the initial gelatin concentration was increased. These morphological changes led to a scaffold's strength enhancement from 0.92 ± 0.22 MPa to 2.04 ± 0.18 MPa when gelatin concentration was increased. THC release slowed down when gelatin concentration increased from 2.5 to 4% w/v, showing a controlled profile within 96 h. Preliminary in vitro test with chondrocytes on scaffolds with 4% w/v gelatin offered higher metabolic activities and cell survival up to 14 days of incubation. Finally the addition of THC did not influence significantly the cytocompatibility and potential antibacterial properties were demonstrated successfully against Staphylococcus aureus.

Texture, Color, and Sensory Features of Low-Sugar Gooseberry Jams Enriched with Plant Ingredients with Prohealth Properties

The aim of this research was to evaluate texture, color, and sensory parameters of low-sugar gooseberry jams with added black chokeberry, elderberry, Japanese quince, flax seeds, wheat germ, and inulin. The jams were stored at two temperatures of 10°C and 20°C. The highest gel strength (Fe) was recorded in the jams with wheat germ (2.75 N), flax seeds (2.74 N), and inulin (1.95 N). The brightest color L⁎ was noted in the gooseberry jams enriched with flax seeds and wheat germ, while the darkest color was noted in those with added black chokeberry and elderberry fruit. In the sensory evaluation, the gooseberry jam without plant ingredients, along with the products enriched with black chokeberry, elderberry, and inulin, scored high at almost 5 on a 5-point scale. The remaining jams had scores of 4.4–4.8 points. Cool storage of jams had a better effect on color and texture, while sensory features were affected to a lesser degree.

Improving quality of an innovative pea puree by high hydrostatic pressure

BACKGROUND

The food industry is continuously innovating to fulfill consumer demand for new, healthy, ready-to-eat products. Pea purees could satisfy this trend by increasing the intake of legumes, which are an important source of nutrients. Moreover, sensorial properties like viscosity could be improved by high hydrostatic pressure (HHP). In this study the effect of a boiling treatment (10 min) followed by HHP at 550 kPa (0, 5 or 10 min) on the rheological properties, associated with enzymatic activity and particle size, as well as on the microbial and sensory quality of a pea-based puree stored for 36 days at 5 °C, has been assessed.

RESULTS

The particle size of pea puree decreased after all processing treatments, but increased during storage in HHP-treated samples. Conversely, boiling treatment showed an increase in polygalacturonase activity at the end of the storage period, with a decrease in particle size, viscosity and stability. However, 5 min of 550 kPa HHP showed the highest mean particle size, mean surface diameter and viscosity regarding the remaining treatments. The microbial load remained low during storage.

CONCLUSIONS

HHP treatment can be used by the food industry to improve the rheological properties, viscosity and stability of pea purees. © 2017 Society of Chemical Industry.

Effect of substituted gelling agents from pomegranate peel on colour, textural and sensory properties of pomegranate jam

A series of pomegranate jams were prepared from a Tunisian ecotype (Tounsi) with different amounts of sugar (10, 20 and 30%) and low-methoxylated pectin (0.2, 0.7 and 1.2%). The most appreciated formulation was that contaning 30% sugars and 0.2% pectin. Then, commercial pectin was substituted by other gelling agents (pomegranate peel powders dried at 50°C vs lyophilized, pectin and fibre extracted from pomegranate peel) for the preparation of pomegranate peel-based jams. The elaborated jams were evaluated for physichochemical, colour, texture and sensory characteristics. Results revealed that the jam (JPP2) elaborated with 0.2% pectin extracted from pomegranate peel exhibited similar overall acceptability to that prepared with commercial pectin. However, it was more acceptable than other pomegranate peel-based jams, which was related to a better appreciation of sweetness and colour. According to the colour and texture measurements, this sample (JPP2) was more reddish and less firm than other samples.

Development of low calorie jams with increased content of natural dietary fibre made from tomato pomace

In this study, four jam formulations were developed, starting with the basic formulation (Jam 1) containing sucrose and without added pectin. Sucrose was partially (50%) replaced by stevioside in formulations of Jam 2 and 3, while in Jam 4 sucrose was completely replaced by fructose and stevioside, making this formulation suitable for diabetic patients. Jam formulations 1 and 2, prepared without added pectin, were thermally stable in the temperature range of 25-90°C, which indicate their potential use as fruit fillings. Jam formulations 3 and 4 were assessed by the sensory panel as more spreadable since tomato pomace particles are incorporated in pectin network which acts as a lubricant. Jam formulations were characterized by a lower total carbohydrate content (17.23-43.81%) and lower energy value (87.1-193.7kcal/100g) when compared to commercial products. Tomato pomace jams contained 15-20 times more dietary fibre than commercial apricot jam.

Preservation of bioactive compounds of a green vegetable smoothie using short time–high temperature mild thermal treatment

Smoothies represent an excellent and convenient alternative to promote the daily consumption of fruit and vegetables in order to obtain their health-promoting benefits. Accordingly, a green fresh vegetables smoothie (77.2% cucumber, 12% broccoli and 6% spinach) rich in health-promoting compounds was developed. Soluble solids content, pH and titratable acidity of the smoothie were 4.3 ± 0.4°Bx, 4.49 ± 0.01 and 0.22 ± 0.02 mg citric acid 100−1 g fw, respectively. Two thermal treatments to reduce microbial loads and preserve quality were assayed: T1 (3 min at 80 ℃) and T2 (45 s at 90 ℃). Fresh blended unheated samples were used as control (CTRL). The smoothie presented a viscoelastic behaviour. T1 and T2 treatments reduced initial microbial loads by 1.3–2.4 and 1.4–3.1 log units, respectively. Samples were stored in darkness at 5 and 15 ℃. Colour and physicochemical changes were reduced in thermal-treated samples throughout storage, which were better preserved at 5 ℃ rather than at 15 ℃. Vitamin C changes during storage were fitted with a Weibullian distribution. Total vitamin C losses of T1 and T2 samples during storage at 15 ℃ were greatly reduced when they were stored at 5 ℃. Initial total phenolic content (151.1 ± 4.04 mg kg−1 fw) was 44 and 36% increased after T1 and T2 treatments, respectively. The 3- p-coumaroyl quinic and chlorogenic acids accounted the 84.7 and 7.1% relative abundance, respectively. Total antioxidant capacity (234.2 ± 20.3 mg Trolox equivalent kg−1 fw) remained constant after the thermal treatments and was better maintained during storage in thermal-treated samples. Glucobrassicin accounted the 81% of the initial total glucosinolates content (117.8 ± 22.2 mg kg−1 fw) of the smoothie. No glucosinolates losses were observed after T2 treatment being better preserved in thermal-treated samples. Conclusively, a short time–high temperature mild thermal treatment (T2) showed better quality and bioactive compounds retention in a green fresh vegetable smoothie during low temperature storage.

Red fresh vegetables smoothies with extended shelf life as an innovative source of health-promoting compounds

Two fresh red vegetables smoothies based on tomato, carrots, pepper and broccoli and rich in health-promoting compounds were developed. The smoothies showed a viscoelastic behaviour. According to sensory analyses, a shelf life of 28 days at 5 °C for fresh blended smoothies was established while thermally-treated ones (3 min, 80 °C) reached up to 40 days at 20 °C and 58 days at 5 °C. For those mild heat treated smoothies, total vitamin C degradation was 2-fold reduced during storage at 5 °C compared to samples stored at 20 °C while the initial total carotenoids, lycopene and total chlorophylls contents were not greatly affected. A 250-g portion of such smoothies covers in a great extend the established recommended daily nutrient intakes for dietary fibre, minerals and vitamin C of different population groups. As main conclusion, a mild thermal treatment and low temperature storage greatly increased the shelf life of red fresh vegetables smoothies and reduced total vitamin C degradation.