Physical and chemical characteristics of Asian sea bass bio-calcium powders as affected by ultrasonication treatment and drying method

The effects of ultrasonication and drying method on particle size and other product characteristics of bio-calcium powder from Asian sea bass (Lates calcarifer) backbone were investigated. Ultrasonication was performed at different amplitudes (60%, 70%, and 80%) for varying periods (15 and 30 min). Ultrasonication at higher amplitudes for a longer time reduced the powder particle size more effectively (p < .05), but had no impact on zeta potential (p > .05). The bio-calcium powder ultrasonicated at 70% amplitude for 15 min had the smallest particle size (3.38 µm) when compared to the control (28.85 µm). When the ultrasonicated bio-calcium was subjected to drying, freeze-drying produced powders with higher calcium solubility but lower whiteness than hot air (tray) drying. The results suggest that the ultrasonication is a potential suitable method to reduce the size of bio-calcium powders, while the drying method slightly affected the product characteristics. The bio-calcium powder could serve as a suitable functional ingredient for food fortification aimed at improving the calcium bioavailability. Particle size of bio-calcium powder from fishbone could affect the mouth feel and calcium solubility when used for food product fortification. This work showed that ultrasonication could be used to obtain up to 10-fold reduction in the particle size of fishbone bio-calcium powders, which promotes increased calcium solubility when subjected to simulated gastrointestinal tract digestion. Few differences in characteristics of the bio-calcium powder were observed for freeze-dried and hot air-dried samples. Thus, an economical, safe, and fast process can be implemented for the production of small particle size bio-calcium powder from fishbone.     

Effect of Asian sea bass bio-calcium on textural,rheological, sensorial properties and nutritive value of Indian mackerel fish spread at different levels of potato starch

Effect of potato starch (2%–4%) and Asian sea bass bone bio-calcium (BC) (0%–10%) on characteristics of Indian mackerel fish spread was investigated. Starch levels had higher impact than bio-calcium concentration on characteristics of fish spread (P < 0.05). Firmness, consistency and cohesiveness of fish spread were raised with increasing starch and BC levels (P < 0.05). Highest lightness (L*) was found in fish spread added with 2% starch and 10% BC (P < 0.05). Highest a*, b*, C*-values but lowest hue angle were obtained in fish spread added with 4% starch and 10% BC (P < 0.05). Higher G' and viscosity were observed in sample added with 4% starch when BC was incorporated at higher level. All fish spreads generally showed shear thinning flow behaviour. Higher acceptability was attained for fish spread containing 4% starch and 10% BC without grittiness. This fish spread showed higher ash with lower moisture, protein and lipid contents than those without BC. Calcium solubility of fish spread was augmented after in vitro gastrointestinal tract system when fortified with 10% BC, and higher solubility of calcium was also noticeable, compared to BC itself. Overall high PUFA, acceptable PV and TBARS value were attained for fish spread fortified with 4% starch and 10% BC.     

Textural,rheological and sensorial properties of mayonnaise fortified with Asian sea bass bio-calcium

Asian sea bass bio-calcium (ASBC) can be fortified in low calcium food product such as mayonnaise. To ensure the smoothness of fortified products, the particle size and fishy compounds of ASBC must be reduced. Ultrasonicated ASBC (U-ASBC) was applied for different times (5–15 min) in the presence of hexane. ASBC and U-ASBC had mean particle size (D₄₃) of 21.87 ± 19.54 and 7.83 ± 7.10 μm, respectively. U-ASBC had lowered volatile compounds. Mayonnaise fortified with ASBC had the augmented firmness, consistency and cohesiveness with increasing ASBC levels (0%–10%) (p < 0.05). ASBC raised lightness (L*) and total color difference (ΔE*), but decreased a* and b*-values of mayonnaise in a dose dependent manner (p < 0.05). Higher G′, G″, viscosity and shear stress value were observed in mayonnaise sample added with ASBC. However, lower acceptability was attained when mayonnaise was added with ASBC at level higher than 2.5% due to fishy odor and grittiness perceived by panelists. The lower droplet size with higher zeta potential of mayonnaise added with ASBC or U-ASBC was related with the lower creaming index. Mayonnaise added with 7.5% U-ASBC (M-UBC-7.5) had higher viscosity with lower creaming and thermal creaming index (p < 0.05) than control and that containing 2.5% ASBC (M-BC-2.5). Denser and smaller droplet sizes were observed for M-BC-2.5 and M-UBC-7.5 than control. Lowest moisture, fat and carbohydrate contents were attained for M-UBC-7.5 with the higher protein, ash and calcium content (p < 0.05). Fortification of mayonnaise with ASBC at 2.5% or U-ASBC at 7.5% increased calcium content by 54 or 174 times, respectively, without sensorial changes.