Optimization of mucilage extraction from chia seeds (Salvia hispanica L.) using response surface methodology

Unraveling the relationship between conditions of ultrasonic-assisted extraction of chia mucilage and viscosity

BACKGROUND

The application of chia mucilage still remains restricted due to the difficulty in achieving high extraction yields. The effect of ultrasonic-assisted extraction (UAE) conditions (temperature, seed:water ratio and time) on the rheological properties of chia mucilage extracts and the relation to the proportion of translucent phase (TP) and opaque phase (OP) of the mucilage in the extract were evaluated.

RESULTS

UAE allowed the efficient extraction of chia mucilage from chia seeds. The desired overall optimal combination to maximize both yield and apparent viscosity was achieved at a seed:water ratio 1:10, a temperature of 25.3 °C and 53.7 min extraction time; the optimal conditions to obtain the maximum yield and minimum apparent viscosity were a seed:water ratio close to 1:20, temperature of 48.8 °C and 208.4 min extraction time.

CONCLUSION

The results obtained in the present work demonstrated that the differences in rheological properties of chia mucilage extracts are due to the extraction methods used. Therefore, it is possible to modulate the extraction conditions in order to obtain different characteristics of the mucilage, maintaining a high extraction yield. © 2022 Society of Chemical Industry.

Characterization of selected dietary fibers microparticles and application of the optimized formulation as a fat replacer in hazelnut spreads

The present work demonstrates the application of the spray drying technique to produce microparticulates of different dietary fibers with particle sizes<10 µm. It examines their role as potential fat replacers for hazelnut spread creams. Optimization of a dietary fiber formulation containing inulin, glucomannan, psyllium husk, and chia mucilage to obtain high viscosity, water holding capacity, and oil holding capacity was conducted. Microparticles containing 46.1, 46.2, and 7.6 weight percentages of chia seed mucilage, konjac glucomannan, and psyllium husk showed a spraying yield of 83.45 %, a solubility of 84.63 %, and viscosity of 40.49 Pas. When applied to hazelnut spread creams, microparticles substituted palm oil by 100 %; they produced a product with a total unsaturated and saturated fat reduction of 41 and 77 %, respectively. An increase in dietary fibers of 4 % and a decrease in total calories of 80 % were also induced when compared with the original formulation. Hazelnut spread with dietary fiber microparticles were preferred by 73.13 % of the panelist in the sensory study due to an enhancement in brightness. The demonstrated technique could be used to increase the fiber content while decreasing the fat content in some commercial products, such as peanut butter or chocolate cream.

Combination of Ultrasound and Heat in the Extraction of Chia Seed (Salvia hispanica L.) Mucilage: Impact on Yield and Technological Properties

The effect of ultrasound in combination of heat on the extraction yield and technological properties of chia seed mucilage was investigated. Chia seeds were mixed with distilled water at a seed-to-water ratio of 1:30. The dispersion was adjusted to pH 9 and treated either with heat extraction by water bath or with heat/ultrasound extraction by probe-type sonication at 50 °C and 80 °C for 30 and 60 min. The yield and technological properties of mucilage samples were evaluated. The heat/ultrasound extraction gave a greater yield of mucilage (6.92–10.52%) as compared to the heat extraction (1.03–1.86%). Images obtained from Scanning Electron Microscope (SEM) have shown that during heat/ultrasound extraction, the amount of mucilage fibers on the surface of chia seed decreased with the increased extraction time. Thus, the yield of mucilage prepared with heat/ultrasound extraction for 60 min was significantly higher than that of mucilage extracted for 30 min. However, the difference between the seed samples treated with heat/ultrasound extraction at different temperatures was not apparent. The mucilage prepared with heat/ultrasound extraction at 50 °C for 60 min had the best technological properties. The amount of protein in the heat/ultrasound extracted mucilage diversified its technological property. Moreover, the mixture of mucilage and whey protein isolate had better miscibility. This study confirms the great potential of application of ultrasound in combination with heat in the extraction of chia seed mucilage.

Optimization of mucilage extraction from Ximenia americana seed using response surface methodology

Ximenia americana is a wild edible fruit essential for human consumption due to its high nutritional and phytochemical constituents with significant antioxidant activity. The fruit seed has high potential in its mucilage content. The present study aimed at optimization of mucilage extraction from the Ethiopian cultivar of Ximeina americana fruit seed. The response surface methodology based on a central composite rotatable design was used for the optimization of aqueous extraction of mucilage. The extraction temperature (50–80 °C), time (1.5–4 h), and water-to-seed ratio (20:1–40:1 v/w) were identified as the major factors influencing mucilage yield, water holding capacity, and protein content. Water to seed ratio and time showed significant (p < 0.01) interaction effect on yield. Interactions of water to seed ratio with time and temperature had significant effects (p < 0.05) on the protein content. Water holding capacity of the mucilage was significantly (p < 0.05) affected by the interaction between temperature and time. Optimum extraction processing conditions were obtained to be extraction temperature of 65.06 °C, time of 1.5 h and water to seed ratio of 37.62:1 v/w. The response variables at this operating conditions were found to be extraction yield of 17.31 %, water holding capacity of 11.48 g/g and protein content of 1.75 %. The result demonstrated that the X. americana seed mucilage could be used as a new source of additives in the dairy industry as a fat replacer due to its potent water holding capacity.

Mucilages: sources, extraction methods, and characteristics for their use as encapsulation agents

The increasing interest in the use of natural ingredients has driven keen research and commercial interest in the use of mucilages for a range of applications. Typically, mucilages are polysaccharide hydrocolloids with distinct physicochemical and structural diversity, possessing characteristic functional and health benefits. Apart from their role as binding, thickening, stabilizing, and humidifying agents, they are valued for their antimicrobial, antihypertensive, antioxidant, antiasthmatic, hypoglycemic, and hypolipidemic activities. The focus of this review is to present the range of mucilages that have been explored as encapsulating agents. Encapsulation of food ingredients, nutraceutical, and pharmaceutical ingredients is an attractive technique to enhance the stability of targeted compounds, apart from providing benefits on delivery characteristics. The most widely adopted conventional and emerging extraction and purification methods are explained and supplemented with information on the key criteria involved in characterizing the physicochemical and functional properties of mucilages. The unique traits and benefits of using mucilages as encapsulation agents are detailed with the different methods used by researchers to encapsulate different food and bioactive compounds.