Carrageenan Gel Research Articles

Salinity alternation with dark treatment enhances the gel quality and quantity of carrageenan in a red alga, Chondrus crispus

Alkali treatment is a commonly used method for carrageenan extraction in the industry. However, this method has some disadvantages, including reduced carrageenan yield and the generation of effluent. To address these issues, this study aimed to determine if salinity alternation combined with dark treatment could improve the yield and quality of carrageenan in the red alga, Chondrus crispus and whether this approach could serve as an eco-friendly alternative to alkali treatment. The results demonstrated that salinity alternation, coupled with dark treatment, enhanced both carrageenan yield and gel strength. Specifically, the most effective method was found to be salinity alternation from 70 psu for 10 days to 10 psu for an additional 10 days, combined with a 20-day of dark treatment period. These findings suggest that salinity alternation along with dark treatment could be a viable alternative to alkali treatment for C. crispus. However, further large-scale studies are needed to assess the economic feasibility of this eco-friendly method.

Healing Potential of the Marine Polysaccharides Carrageenan and Ulvan on Second-Degree Burns.

The treatment of second-degree burn wounds presents a significant clinical challenge, often characterized by prolonged healing times and risk of complications. In this study, the wound healing potential of bioactive marine sulfated polysaccharides ulvan and carrageenan formulated in gels at concentrations of 1.5%, 5.0%, and 10% w/w was evaluated. Hairless female SKH-hr2 mice (n = 7 per treatment) with burn-inflamed skin were treated with the polysaccharide-based gels, and the therapeutic efficacy was assessed using a comprehensive array of evaluation methods, including a histopathological analysis, clinical observation, photo-documentation, an image analysis, an evaluation of biophysical skin parameters, and FT-IR spectroscopy. Our findings indicate that the 10% w/w carrageenan gel exhibited significant enhancement in wound healing, particularly in the early stages of the healing process. This was evidenced by the restoration of the α-helix structure of collagen and the configuration of glycosaminoglycans, as demonstrated by FT-IR absorption bands of the skin both in vivo and ex vivo. Furthermore, the 5% w/w ulvan gel also demonstrated notable efficacy in promoting wound healing, particularly in the later stages of the healing process. These results suggest that carrageenan and ulvan gels hold promise for improving the efficiency of wound healing in second-degree burn wounds. Our study contributes to the understanding of the therapeutic potential of marine polysaccharides and provides insights into their mechanism of action in promoting wound healing.

Viscoelastic Reversibility of Carrageenan Hydrogels under Large Amplitude Oscillatory Shear: Hybrid Carrageenans versus Blends.

The viscoelastic response of carrageenan hydrogels to large amplitude oscillatory shear (LAOS) has not received much attention in the literature in spite of its relevance in industrial application. A set of hybrid carrageenans with differing chemical compositions are gelled in the presence of KCl or NaCl, and their nonlinear viscoelastic responses are systematically compared with mixtures of kappa- and iota-carrageenans of equivalent kappa-carrageenan contents. Two categories of LAOS response are identified: strain softening and strain hardening gels. Strain softening gels show LAOS non-reversibility: when entering the nonlinear viscoelastic regime, the shear storage modulus G' decreases with increasing strain, and never recovers its linear value G0 after successive LAOS sweeps. In contrast to this, strain hardening carrageenan gels show a certain amount of LAOS reversibility: when entering the nonlinear regime, G' increases with strain and shows a maximum at strain γH. For strains applied below γH, G0 shows good reversibility and the strain hardening behavior is maintained. For strains larger than γH, G0 decreases significantly indicating an irreversible structural change in the elastic network. Strain hardening and elastic recovery after LAOS prevail for hybrid carrageenan and iota-carrageenan gels, but are only achieved when blends are gelled in NaCl, suggesting a phase separated structure with a certain degree of co-aggregated interface for mixed gels.

Conversion of iota carrageenan hydrocolloids to hydrophobic hydrocolloids, by the replacement of potassium to barium ion, for the entrapment of water insoluble drugs

To entrap the water-insoluble medicine, the current innovation provides a cost-effective solution to the increasing need for hydrophobic gel. Improving the bioavailability of a medicine that is poorly soluble begins with entrapping the substance. By only switching out the monovalent ions for divalent ones, the researchers hope to increase the hydrophobicity of their material. In this experiment, barium ions were used instead of potassium ions in the iota carrageenan to make structural, chemical, and physicochemical changes easier during transformation. Hydrophobicity was determined qualitatively by observing the ability to trap small oil particles and repel water, moreover, the quantitative investigation was carried out using the weight loss method to determine the metal ion water isolation value and drug entrapment value within the core of barium linked carrageenan gel. The metal’s weight loss metal water affinity was determined to be 90% after 24 h, but it was only 67% with the synthesized gel coating the metal, this clearly shows that the barium gel had greater water protection activity. Furthermore, the barium-linked gel exhibited three times the entrapment capacity of the parent gel, and it successfully encased the water-insoluble medication with controlled release. The current study shows how the attached ion to the polymer changes its hydrophilic behavior into a hydrophobic one. This is a new and inexpensive way to do things. However, up until this point, the addition of the hydrophobic substrate and the functionalization of the polymer have been utilized. This leads to a plan that shows promise for improving the ability of hydrophobic hydrocolloid gels to hold drugs that do not dissolve in water.

Thermoresponsive gel containing bilirubin nanoparticles exerts anti-inflammatory effects by inhibiting neutrophil infiltration and augmenting interleukin-10 levels in carrageenan-induced rat paw edema.

Topical corticosteroids treat cutaneous inflammation but have side effects. In earlier studies, bilirubin exhibited anti-inflammatory effect, but its hydrophobicity and poor absorption limit its potential. Synthesis of bilirubin nanoparticles (BNP) and bilirubin nanoparticles gels (BNP gel) to study the anti-inflammatory effect of topical BNP gel against carrageenan-induced rat paw edema in Wistar rats. BNP were synthesized, and BNP gels were prepared by mixing BNP of different concentrations with pluronic F-127 (PF-127). A different group for each formulation was assigned with five rats in each group. After 1 h of carrageenan (1% [w/v]) injection in each group, different gels were applied topically to their respective groups. Paw edema size, percent inflammation, percent edema inhibition, and inhibition time50 were evaluated. Interleukin-10 (IL-10) levels and neutrophil infiltration in rat paw tissue were evaluated by enzyme-linked immunosorbent assay and hematoxylin and eosin, respectively. Synthesized spherical-shaped BNP had negative zeta potential. BNP gels markedly reduced paw edema size and % inflammation as compared to carrageenan and bulk bilirubin gel (Bulk B gel) treated group and significantly increased IL-10 levels and inhibited neutrophil infiltration. BNP gels exhibited a better anti-inflammatory effect than bulk B gel and comparable anti-inflammatory potential with clobetasol.

Isolation and Identification of Bitter Compounds in Ginseng (Panax ginseng C. A. Mey.) Based on Preparative High Performance Liquid Chromatography, UPLC-Q-TOF/MS and Electronic Tongue

As a traditional Chinese medicinal herb, ginseng (Panax ginseng C. A. Mey.) is commonly used to treat common diseases, for example, esophageal cancer and myasthenia gravis. Furthermore, ginseng is also processed into a functional food additive that is utilized to improve the freshness of chicken soup and make health wine. Unfortunately, ginseng (Panax ginseng C. A. Mey.) has already shown a noticeable bitterness during its application process. In this research, the bitter substances in ginseng (Panax ginseng C. A. Mey.) after two common preparation processes (water extraction and ethanol extraction) were separated, purified and identified by preparative high performance liquid chromatography (prep-HPLC), high performance liquid chromatography with diode array detector (HPLC-DAD), ultra-performance liquid chromatography coupled with high-resolution quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF/MS) and an electronic tongue. The results indicated that compared with the other four bitter compounds, the ginsenoside Rb1 had the highest bitterness value, followed by 20(S)-ginsenoside Rg2, ginsenoside Rg1, ginsenoside Rf and ginsenoside Rb3. Upon the evaluation of results to reduce the bitterness of ginseng extract, we found that the composite embedding system of chitosan adsorption in the ginseng carrageenan gel microsphere (K/MC/MCG) could effectively reduce the bitterness.

Understanding the rheological properties from linear to nonlinear regimes and spatiotemporal structure of mixed kappa and reduced molecular weight lambda carrageenan gels

Blends of different carrageenan types have proven to be useful in tuning carrageenan gels' rheological properties. However, understanding the influence of a reduced molecular weight on the gelation of mixed carrageenan gels is still limited. Here, the gelation of mixed kappa-(KC) and reduced molecular weight lambda-(LC) carrageenan systems at different mixing ratios was evaluated using rheology from linear to nonlinear regimes via large amplitude oscillatory shear (LAOS), small-angle X-ray scattering (SAXS), pulsed nuclear magnetic resonance (NMR) and particle tracking. A single-step increase in moduli was seen for mixed kappa-lambda carrageenan (KCLC) gels with decreasing temperature while LC demonstrated nongelling behavior. The LAOS response of KCLC mixed gels showed the characteristic signature of strain-stiffening corresponding to the difference in the size and dynamics of the aggregates. The cross-sectional size revealed by SAXS and dynamics of the aggregates revealed by pulsed-NMR demonstrate that KCLC gels has higher segmental mobility and formed small aggregates that reduce with decreasing the KC fraction whereas pure KC gels formed large and rigid aggregates. Thus, the spatiotemporal features of the aggregates are considered to be the origin of the strain-stiffening in mixed gels under large deformation. Moreover, the microscopic properties of the KCLC gels evaluated using particle tracking revealed a homogenous network suggesting the formation of a swollen KC network in the LC solution. Hence, our findings provide insights into the rheological behavior and network structure design of KC and reduced molecular weight LC mixed gels.

The effects of stem bromelain on the gelation behavior of kappa carrageenan under linear and nonlinear rheological regimes

Carrageenans have shown a versatile and wide range of applications in the food and biomedical fields. To tune the rheological properties and improve the biological functions of carrageenan gels, the effect of stem bromelain (SBr) on the intermolecular interaction and rheological property of κ-carrageenan (κC) was investigated. The viscoelastic properties and gel network structure of pure SBr, κC, and SBr/κC mixtures were studied using dynamic rheology in the linear and nonlinear viscoelastic regimes. Different SBr/κC mixtures were prepared with varying final pH levels (pH 6.06, 6.95, and 8.08). The time series and frequency dependence of SBr/κC mixtures in the linear viscoelastic regime showed that the elastic modulus is (3–10 times) greater than the viscous modulus, indicating network structure formation. The temperature dependence of the viscoelastic moduli SBr/κC mixtures exhibited a significantly improved physical property than the pure SBr and κC, demonstrating synergistic relation between SBr and κC via enhanced electrostatic interaction. By increasing the pH level of the mixtures, a decrease in the shear moduli was observed attributed to the increasing repulsive interaction between SBr and κC. The observed nonlinear rheological responses suggest a transiently crosslinked network. Accordingly, with the gentle imposition of increasing stress levels, the nonlinear responses suggest that SBr/κC is a stress-mediated, highly entangled complex network with a pH-controlled dynamic viscoelastic property. Therefore, our results provide structural insights into the microscopic origins of the rheological behavior of SBr/κC mixtures as a basis for precise material design.

Elaborating Spatiotemporal Hierarchical Structure of Carrageenan Gels and Their Mixtures during Sol–Gel Transition

Elaborating Spatiotemporal Hierarchical Structure of Carrageenan Gels and Their Mixtures during Sol–Gel Transition

PH-triggered polymeric nanoparticles in gel for preventing vaginal transmission of HIV and unintended pregnancy

Human Immunodeficiency Virus/Acquired Immunodeficiency Syndrome (HIV/ AIDS) and unplanned pregnancy affect female reproductive health globally. A single product providing a dual purpose of HIV prophylaxis and contraception may improve adherence to the therapy. Thus, we formulated a female-centric multipurpose prevention technology (MPT) comprising of nanoparticle loaded vaginal gel formulation acting as a contraceptive and microbicide. Eudragit® S100 nanoparticles of Atazanavir sulphate (ATZ; antiviral) and Fluoxetine hydrochloride (FLX; repurposed spermicide) were prepared for pH dependent drug release and loaded in carrageenan and HPMC K200M gel. The particle size of ATZ and FLX nanoparticles was 396.7 ± 20.64 nm and 226.5 ± 2.08 nm respectively. The in vitro release of the gel formulation in simulated seminal fluid (pH 7.6) showed 96.16% and 95.98% release of ATZ and FLX respectively at the end of 8 h. The in vitro anti-HIV and spermicidal activity of the formulation was above 80% for low drug concentrations. In vivo studies on murine model showed no signs of inflammation or vaginal epithelial injury. Curcumin based imaging confirmed the retention of the formulation in the reproductive tract of mice with minimal leakage. Nanoparticles in gel enabled non-invasive and localised delivery with minimal side effects and can be an effective prophylactic therapy.

Structural and functional properties and digital image texture analysis of gelatin, pectin, and carrageenan gels with honey addition.

Gels combined with honey might generate new possibilities of textures in food development. This work explores the structural and functional properties of gelatin (5 g/100 g), pectin (1 g/100 g), and carrageenan (1 g/100 g) gels with different content of honey (0-50 g/100 g). Honey decreased the transparency of gels and made them more yellow-greenish; all of them were firm and uniform, especially at the highest honey content. The water holding capacity increased (63.30-97.90 g/100 g) and moisture content, water activity (0.987-0.884) and syneresis (36.03-1.30 g/100 g) decreased with the addition of honey. This ingredient modified mainly the textural parameters of gelatin (Hardness: 0.82-1.35 N) and carrageenan gels (Hardness: 2.46-2.81 N), whereas only the adhesiveness and the liquid like-behavior were increased in the pectin gels. Honey increased the solid behavior of gelatin gels (G': 54.64-173.37 Pa) but did not modify the rheological parameters of the carrageenan ones. Honey also had a smoothing effect on the microstructure of gels as observed in the scanning electron microscopy micrographs. This effect was also confirmed by the results of the gray level co-occurrence matrix and fractal model's analysis (fractal dimension: 1.797-1.527; lacunarity: 1.687-0.322). The principal component and cluster analysis classified samples by the hydrocolloid used, except the gelatin gel with the highest content of honey, which was differentiated as a separate group. Honey modified the texture, rheology, and microstructure of gels indicating that it is possible to generate new products to be used in other food matrices as texturizers.

Novel gels and films to mask boar taint in entire male pork

Boar taint masking strategies were developed using hydrocolloids and spices to produce edible gels and films. Carrageenan (G1) and agar-agar (G2) were used for the gels and gelatin (F1) and alginate+maltodextrin (F2) for the films. The strategies were applied to both castrated (control) and entire male pork with high levels of androstenone and skatole. The samples were evaluated sensorially by a trained tasting panel through quantitative descriptive analysis (QDA).Lower hardness and chewiness of entire male pork, with high levels of boar taint compounds object of study, were found with the carrageenan gel, due to the better carrageenan gel adherence to the loin. The films showed that the gelatin strategy tended to have a certain “sweet” taste, and a higher overall masking than the alginate+maltodextrin film. In conclusion, a trained tasting panel found that gelatin film masked boar taint the most, followed by the alginate+maltodextrin film and the carrageenan-based gel.

Soybean oleosome-based oleogelsviapolymer-bridging based structuring. Mechanical properties at large deformations

Oleosomes have emerged in the last decade as a multipurpose oil-in-water emulsion suitable for engineering new lipids materials. The need to increase alternative and sustainable methods to modulate the rheological properties of emulsions has been the leading research interest in the oleogelation field. Soybean oleosomes are evaluated as building blocks for creating oleogels in combination with sodium alginate or ι-carrageenan as the structuring elements. Polymer bridging provides a route to produce compact soft, malleable gels by exploiting attractive electrostatic interactions between negatively charged polysaccharides and oleosome surfaces. We investigated the viscoelastic properties of concentrated polymer bridged gels by oscillatory rheological measurements. The rheological characteristics are governed predominantly by the type of polysaccharide and by the ratio between polysaccharide and oleosome content. One yielding step at low strains indicates the breaking of polysaccharide bridging bonds and was visible in all samples. A two-step yielding process, where the second step corresponds to the cage-breaking process, was present at polysaccharide/oleosome ratios where optimum bridging occurs for alginate and carrageenan, 0.005 g/g, 0.01 g/g, respectively. Nonetheless, the bumps corresponding to the second yielding point were more prominent in alginate gels than in carrageenan gels due to the greater bridging ability of alginate. Identifying these rheological hallmarks could provide new ideas towards the improved design of plant-based fatty food products,e.g., cream cheeses and vegan sausages surrogates.

Peanut protein-polysaccharide hydrogels based on semi-interpenetrating networks used for 3D/4D printing

The rise of 3D printing technology has made the personalization of food possible. In this study, peanut protein-polysaccharide semi-interpenetrating networks were constructed to improve the gelling and printing properties of composite hydrogels. The rheological and mechanical test results showed that the storage modulus and fracture stress of peanut protein composite hydrogels increased with increasing carrageenan and gellan gum concentrations. The storage modulus (G′) and hardness of the composite hydrogels with 1.5% polysaccharide addition reached above 104 Pa and 700 g, respectively. The thermal reversibility of both carrageenan and gellan gum gels meant that composite hydrogels could be created as recyclable printable edible inks for 3D food printing. In addition, the composite hydrogels were designed to change color in response to alterations in pH, which meant they could be used in 4D food printing applications, i.e., in situations where the ink changes its attributes sometime after printing. The results of this study should facilitate the rational design and fabrication of plant-based edible inks that can be used for the development of personalized foods with unique properties.

Carrageenan extraction from red seaweed (Kappaphycopsis cottonii) using the bead mill method

Carrageenan extraction can be carried out using a novel method, the bead mill, to produce a high yield and good characteristics of carrageenan. This study aimed to evaluate the environmentally friendly carrageenan extraction method using a bead mill and the physicochemical properties of the extract. Factors such as seaweed concentration, extraction time, agitator speed, and temperature were analyzed. Furthermore, the yield, gel strength, viscosity, and sulfate content were evaluated. The results show that the carrageenan yield, gel strength, viscosity, and sulfate content were significantly affected by seaweed concentration, extraction time, and extraction temperature in a bead mill method. They were not affected by agitator speed. The optimum condition was obtained at a concentration of 1.90 % w/v, an extraction time of 50.26 min, and a temperature of 51.35 °C. The carrageenan had a yield of 67.86 %, gel strength of 68.49 g/cm2, the viscosity of 11.81 cP, sulfate content of 15.35 %, gelling point of 29.33 °C, the melting point of 44.70 °C, the water content of 5.69 %, ash content of 26.54 %, pH of 8.27, and purity of 55.67 %. FTIR analysis confirmed that the carrageenan type was kappa-carrageenan. Thus, the bead mill method can be considered an effective way to obtain high yields with a shorter time in extracting carrageenan from seaweed. Total operating cost of bead mill was lower than chemical method. Nevertheless, the physicochemical properties of carrageenan obtained by this method were lower than that obtained by the conventional KOH method, especially the gel strength.

Magnetic Response Detects the Strength of Carrageenan Network.

The effect of carrageenan concentration on the magneto-rheological effect of magnetic gels with a magnetic particle concentration of 50 wt.% was investigated under a magnetic field of 50 mT by dynamic viscoelastic measurements. The change in the storage modulus for magnetic gels due to the magnetic field was 3.0 × 103 Pa at a carrageenan concentration of 1.0 wt.% and increased with the concentration. The modulus change showed a maximum of 2.3 × 104 Pa at ~2.0 wt.% and became lower at higher concentrations. This is an interesting phenomenon, which was first observed in this study. The critical strain, the strain where the storage modulus intersects the loss modulus in the strain dependence of the modulus, was much higher than that for carrageenan gels, indicating a strong interaction between the magnetic particles and carrageenan. At 0 mT, the critical strain for the magnetic gels increased remarkably with decreasing the concentration, indicating that magnetic gels have a structure that does not flow easily at concentrations below 1.75 wt.%. It is considered that the structure hardly flows, hindering the movement of particles. At high concentrations, the SEM photographs showed both a particle network of magnetic particles and a dense carrageenan network. It can be considered that the movement of magnetic particles was hindered due to these factors at high concentrations.

Growth rate, concentration, and quality of carrageenan in two strains of seaweed Kappaphycus striatus grown in Khanh Hoa waters

In this study, two strains of seaweed Kappaphycus striatus (Payaka brown and Sacol brown) derived from Philippines after nearly 20 years of cultivation, were cultivated in Van Phong Bay and Cam Ranh Bay (Khanh Hoa, Vietnam) to re-evaluate the growth characteristics, concentration, and quality of carrageenan. The results showed that the ecological area affects the growth (fresh weight, growth rate, dry matter accumulation rate), content, and quality of carrageenan (gel strength and viscosity) of the two seaweed strains after 2, 4, 6, 8, 10, 12 weeks of cultivation. The highest biomass of both strains was reached after 8 weeks of cultivation in Van Phong Bay and 10 weeks in Cam Ranh Bay. The fresh weight, the dry weight, and the growth rate (343.33 g, 42.67 g, 1.30%.day-1, respectively) of the Sacol brown strain were similar to that of the Payaka brown strain at the Van Phong Bay. However, the dry matter accumulation rate (12.45%) and the carrageenan content (24.50%/w) of the Sacol brown strain were highest when cultivated in Van Phong Bay. The growth rate, concentration, and quality of carrageenan in two seaweed strains in Van Phong Bay and Cam Ranh Bay were lower than before.

Analisis Produksi Alkali Treated Cotoni Chips (ATCC) dan Alkali Treated Soinosum Chips (ATSC) Pada PT. Inti Nusa Raya Indonesia di Kabupaten Bombana

This research is motivated by the author's observations regarding the production of ATCC and ATSC. This study aims to determine the production process and the amount of ATCC and ATSC production at PT. Inti Nusa Raya Indonesia in Bombana Regency. This research was conducted at PT. Inti Nusa Raya Indonesia in Bombana Regency from October to December 2021. The data analysis used in this study is a quantitative descriptive analysis technique. The population in this study is PT. Inti Nusa Raya Indonesia until this research was carried out. Determination of informants in this study using purposive sampling technique by directly appointing respondents to be interviewed. The informants in this study are the production manager of PT. The core of Nusa Raya Indonesia. The type of data used in this research is quantitative data. This study's results indicate the production process of ATSC and ATSC at PT. Inti Nusa Raya Indonesia is carried out mechanically and carried out in several stages, namely the process of receiving raw materials, weighing, sorting, sifting, soaking, draining, washing, drying, cutting, chip cleaning, mixing, packaging, labeling, final storage and final loading of the product. . The results showed that in the production process of ATSC and ATSC, the raw material of seaweed used was 45 days of harvest to get the appropriate quality of carrageenan and good gel strength. While the concentration of KOH and NaOH used was 7-8% with a temperature of 70-80 c and cooked for 3 hours, drying time was 3-4 days when the weather was sunny and 7-10 days when the weather was cloudy.

Polyvinyl alcohol-based films plasticized with an edible sweetened gel enriched with antioxidant carminic acid

Edible sweetened gels are commonly used in bakery products. The aim of this work is to show that certain edible gels can be used as functional modifiers for biodegradable polymers. These gels are rich in glucose and sugars, containing much less water. To date, sugars (glucose, maltose, sucrose, and d -allulose), have also been used as natural plasticizers for polysaccharides to form edible films. In this work, we prepared an edible gel based on glucose, sugar and carrageenan as a gelling agent and tested the gel's plasticizing effect on polyvinyl alcohol, PVA. Carminic acid, a natural pigment and a powerful antioxidant with antiradical activity, was added to the gels. The optimum plasticizing effect was obtained from 1:1 gel: polymer mixing ratio with 28.6 wt% total sugars. Carminic acid also assisted with low oxygen permeation (OP, 3.4 cm 3 μm/m 2 .day.atm) values due to its oxidative radical scavenging chemistry. In aqueous and ethanoic solutions, the films released carminic acid in a sustained manner and within 36 h, strong inhibition was measured against standard stable free-radical molecules known as DPPH and ABTS +• . Finally, the films demonstrated effective color change upon exposure to ammonia vapors that can be exploited towards food spoilage detection. These materials could be effectively used as freestanding, protective antioxidant barrier films or can be laminated with other hydrophobic thermoplastics for general packaging applications. • A sugar based carrageenan gel was used as plasticizer for PVA. • The gel contained carminic acid, which acted as a strong antioxidant. • The plasticized films had very low oxygen permeation values. • The films changed color upon exposure to ammonia vapors. • The plasticized films could be used for multilayer packaging.

Effects of selected environmental conditions on growth and carrageenan quality of laboratory-cultured Kappaphycus alvarezii (Rhodophyta) in Fiji, South Pacific

The impacts of environmental conditions (temperature, salinity, and nutrients) on growth, semi-refined carrageenan yield, gel strengths, and viscosity were assessed on the red seaweed Kappaphycus alvarezii in laboratory culture. Results showed that K. alvarezii had a higher daily growth rate (0.94% day-1) at higher temperature (30 °C). Its semi-refined carrageenan yield was high (75.79%) at a combination of low salinity (25 ppt) and high temperature (30 °C). Conversely, gel strengths made out of semi-refined carrageenan from K. alvarezii cultured at low temperature (24 °C) demonstrated a higher compression (5.84 N) and high penetration strength (0.29 N). Highest viscosity (289.50 cP) was attained at a combination of high temperature, low salinity, and high nutrient concentration. Gels made from carrageenan of K. alvarezii grown in a higher temperature (30 °C) mixed with pineapple juice showed higher compression strength demonstrating that carrageenan extracted from cultured K. alvarezii is a good thickening agent for fruit jellies or similar food products that do not require refrigeration. This could benefit communities in rural, non-electrified communities/areas of Fiji and other South Pacific Islands that could use K. alvarezii as an alternative gelling agent in the making of food products contributing towards their food and economic security.