Effect of the addition of Spirulina sp. biomass on the development and characterization of functional food

Effects of molecular structure and charge state on the foaming and emulsifying properties of Spirulina protein isolates

Microalgae protein holds great potential for various applications in the food industry. However, the current knowledge regarding microalgae protein remains limited, with little information available on its functional properties. Furthermore, the relationship between its molecular structure and functional properties is not well defined, which limits its application in food processing. This study aims to addresses these gaps though an analysis of the emulsibility and foamability of various soluble protein isolates from two species of Spirulina (Arthospira platensis and Spirulina platensis), and the functional properties of Spirulina protein isolates in relation to its molecular structure and charge state. Results revealed that the degree of cross-linking and aggregation or folding and curling of protein tertiary structures was higher in the highly soluble Spirulina protein isolates (AP50% and SP50%) than in the low-solubility isolates (AP30% and SP30%). The foaming capacity (FC) of AP50% and SP50% was found to be lower than that of AP30% and SP30%. Spirulina protein isolates can stably adsorb at the air-water interface for at least 20 min and possessed good interfacial activity. A high pH value was found to promote cross-linking of protein particles at the oil-water interface, thereby reinforcing the internal network structure of emulsions and increasing viscosity. These findings provide preliminary insights for potential applications of Spirulina protein isolates in food production, especially towards quality improvement.

Enhancing the Biological Effects of Bioactive Compounds from Microalgae through Advanced Processing Techniques: Pioneering Ingredients for Next-Generation Food Production

The heightened interest in healthy dietary practices and the preference for fresh, minimally processed foods with reduced additives have witnessed a significant surge among consumers. Within this context, bioactive compounds have garnered attention as potent agents offering beneficial biological effects when integrated into food formulations. Nevertheless, the efficacy of these bioactive compounds in product development encounters numerous challenges during various processing and storage stages due to their inherent instability. Addressing these limitations necessitates exploring novel technological approaches tailored explicitly to the application of bioactive compounds in food production. These approaches should not only focus on preserving the bioactive compounds within food matrices but also on retaining the sensory attributes (color, taste, and aroma) of the final food products. The impact of microalgae and their bioactive compounds on human health and well-being has been extensively reported in the literature. However, there is still a gap regarding the processing and stability of microalgal bioactive compounds to improve their application in the food industry. The main goal of the present work is to point out how to overcome technological challenges in enhancing the stability of bioactive compounds from microalgae for optimal food applications.

A new application of hydrocolloids from Echinops setifer (Shekartighal): Mayonnaise-type sauces

Due to the importance of the production of functional and nutraceutical foods with high added value, Shekartighal was used to develop ready-made functional mayonnaise-type sauces and evaluate their physicochemical, sensory, and antioxidant properties over 60 days of storage. Shekartighal had, on average, 76.85% carbohydrate, 9.24% protein, 4.91% fat, 1.74% ash, 7.26% moisture, 20.38 mgGAE/g total phenol content, 14.31 μM ferrous sulphate/g, and 145.12 μg/mL antioxidant activity. The results indicated that Shekartighal had high water absorption capacity (408.01%) and emulsion stability (91.83%). Following the textural and sensorial study, the product that stood out as the best performer was the sauce containing 3% Shekartighal. Consequently, this product was selected for further evaluation, where its physicochemical and antioxidant properties were assessed for a 60-day duration under refrigerated storage (4°C). The formulation with 3% Shekartighal presented significantly more phenolic content and antioxidant properties than the control. During the 60-day refrigerated storage (4°C) period, the physicochemical and antioxidant parameters of the enriched sauce remained stable. The addition of Shekartighal to the sauce significantly improved its nutritional quality, and the sauce enriched with 3% Shekartighal demonstrated the most favorable characteristics among the different concentrations tested. Overall, these findings suggest that Shekartighal could be utilized as a natural ingredient to create a functional sauce with notable antioxidant and nutritional properties.

Antimicrobial activity of Spirulina platensis extract on total mesophilic and psychrophilic bacteria of fresh tilapia fillet

Spirulina platensis has a wide range of activities, notably antibacterial property against food pathogens. This study investigates the antibacterial activity of S. platensis extract on Total Mesophilic and Psychrophilic Aerobic Bacteria. The results were compared using statistical analysis and the predicted model values using artificial intelligence-based models such as artificial neural network (ANN) and adaptive neuro fuzzy inference system (ANFIS) Models. The extraction of spirulina was done by using the freeze-thaw method with a concentration of 0.5, 1 and 5% w/v. Before the application of the extract, initial microbial load of fillets was analyzed the and the results were used as control. After application analysis was performed at 1, 24 and 48 h of storage at 4 °C. Based on the statistical analysis result the S. platensis extracts' antimicrobial activity over TMAB of fresh tilapia fish fillets at 1, 24 and 48 h was using EA from 2.5 log10 CFU/g during the control stage to 1.8, 1.1 and 0.7 log10 CFU/g respectively whereas EB and EC was from 2.1 and 2.2 log10 CFU/g at control to 1.5, 0.8, 0.5 log10 CFU/g and 1.23, 0.6 and 0.32 log10 CFU/g respectively at the specified hour interval. Similarly, the three extracts over TPAB were from 2.8 log10 CFU/g at control time to 2.1, 1.5 and 0.9 in EA, while using EB reduces from 2.8 log10 CFU/g to 1.9, 1.3 and 0.8 log10 CFU/g at 1, 24 and 48 h respectively. Although EC presented the reduction from 1.9 log10 CFU/g to 1.4, 1 and 0.5 log10 CFU/g. This was supported by ANN and ANFIS models prediction.

Effect of Electrofiltration on the Dewatering Kinetics of Arthrospira platensis and Biocompound Recovery

Arthrospira platensis (A. platensis) is a microalga with a wide range of commercial uses. One of the main concerns that needs to be addressed in microalgae biorefineries is the costs associated with the harvesting and concentration steps. Filtration has been shown to be an effective technique for concentrating microalgae and recent studies have attempted to enhance membrane filtration by applying an external electric field to the filtration cell. This study consisted of assessing the use of electrically assisted filtration (electrofiltration) at 60 A/m2 and 1 bar for the dewatering of A. platensis, as well as the effect of pretreating the microalgae with ultrasounds (US) on the filtration process. Untreated A. platensis exhibited better filtration kinetics than US-treated A. platensis, and electrofiltration was found to increase the cake dryness. More protein and pigments were present in the US-treated microalgae solution compared to the untreated microalgae, which led to the presence of higher concentrations of protein and pigments in the filtrate streams after pressure filtration at 1 bar without the application of an external electric field. Electrofiltration was found to consume less energy compared to traditional drying techniques used for A. platensis. However, electrofiltration degrades the biocompounds present in the filtrate and cake due to pH changes and other electrophoresis phenomena, which shows the need to optimize the process in future work.

Functional properties of bioactive compounds from Spirulina spp.: Current status and future trends

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Functional foods that contain bioactive compounds (BC) and provide health benefits;

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Spirulina is a cyanobacterium considered blue microalgae rich in BC;

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BC from Spirulina have interesting health effects;

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Chlorophyll, carotenoids, and phycocyanin are natural corants from Spirulina;

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Spirulina has potential as an ingredient for application in functional foods.

Functional foods show non-toxic bioactive compounds that offer health benefits beyond their nutritional value and beneficially modulate one or more target functions in the body. In recent decades, there has been an increase in the trend toward consuming foods rich in bioactive compounds, less industrialized, and with functional properties. Spirulina, a cyanobacterium considered blue microalgae, widely found in South America, stands out for its rich composition of bioactive compounds, as well as unsaturated fatty acids and essential amino acids, which contribute to basic human nutrition and can be used as a protein source for diets free from animal products. In addition, they have colored compounds, such as chlorophylls, carotenoids, phycocyanins, and phenolic compounds which can be used as corants and natural antioxidants. In this context, this review article presents the main biological activities of spirulina as an anticancer, neuroprotective, probiotic, anti-inflammatory, and immune system stimulating effect. Furthermore, an overview of the composition of spirulina, its potential for different applications in functional foods, and its emerging technologies are covered in this review.

Bioprocess Optimization for the Production of Arthrospira (Spirulina) platensis Biomass Enriched in the Enzyme Alkaline Phosphatase

The enzyme alkaline phosphatase (ALP) is gaining interest because it exerts bioactive properties and may be a potentially important therapeutic agent for many disorders and diseases. Microalgae are considered an important novel source for the production of diverse bio-compounds and are gaining momentum as functional foods/feeds supplements. So far, studies for the production of ALP are limited to mammalian and partly to some heterotrophic microbial sources after its extraction and/or purification. Methods: Arthrospira was cultivated under P-limitation bioprocess and the effect of the P-limitation degree on the ALP enrichment was studied. The aim of this work was to optimize the cultivation of the edible and generally-recognized-as-safe (GRAS) cyanobacterium Arthrospira platensis for the production of single-cell (SC) biomass enriched in ALP as a potential novel functional diet supplement. Results: The results revealed that the relationship between intracellular-P and single-cell alkaline phosphatase (SC-ALP) activity was inverse; SC-ALP activity was the highest (around 50 U g-1) when intracellular-P was the lowest possible (around 1.7 mg-P g-1) and decreased gradually as P availability increased reaching around 0.5 U g-1 in the control cultures. Under the strongest P-limited conditions, a more than 100-fold increase in SC-ALP activity was obtained; however, protein content of A. platensis decreased significantly (around 22-23% from 58%). Under a moderate P-limitation degree (at intracellular-P of 3.6 mg-P g-1), there was a relatively high SC-ALP activity (>28 U g-1) while simultaneously, a relative high protein content (46%) was attained, which reflects the possibility to produce A. platensis enriched in ALP retaining though its nutritional value as a protein rich biomass source. The paper presents also results on how several parameters of the ALP activity assay, such as pH, temperature etc., and post-harvest treatment (hydrothermal treatment and biomass drying), influence the SC-ALP activity.