Tag Archives: Calcium

Determination of Mineral Contents of Edible Parts of Shellfishes from Okpoka Creeks in Rivers State, Nigeri (Published)

The study was conducted to determine the mineral contents of some selected shellfishes from Okpoka Creek in River State. Copper, iron, manganese, calcium and sodium were quantified using Atomic Absorption Spectrophotometric method and the concentration of the minerals varied between the different species of shellfishes. High amount of calcium was recorded in C. guanhumi (212.33±1.45mg/100g) while the lowest was observed in T. fuscatus (48.39±1.4mg/100g). The manganese content was higher in T. coronata (1.82±0.10 mg/100g) and lower in T. fuscatus (0.25±0.11mg/100g). Meanwhile the iron content was more in C. gasar (29.5±0.5mg/100g) and lower in C. amnicola (8.07±1.485mg/100g). However, T. coronate showed higher content of copper (10.15±0.17mg/100g) while the lowest copper content was observed in T. fuscatus (2.15±0.43m g/100g). C. amnicola (115.9±0.26mg/100g) recorded the highest amount of sodium while T. coronate (17.43±0.11mg/100g) recorded the least sodium content. The results suggest that these shellfishes are nutritious and are valuable additions to our diet.

Keywords: Calcium, Copper, Iron, Manganese and Zinc, Shellfish


The Influence of calcium sources and concentration on the storage performance of strawberry fruit was determined by harvesting the fruits at red stage and treatment with calcium nitrate, calcium gluconate and calcium chloride at 0% (distilled water), 0.5, 1.0 and 1.5% calcium solutions by dipping for 30 seconds. The calcium sources, concentration and the interaction of calcium sources and concentration significantly affected the storage performance of strawberry fruit. While all the three sources and concentrations were effective in decreasing the storage associated changes i.e. weight loss, decline in marketable fruits, loss of organoleptic quality, increase in TSS, decline in reducing sugars, total sugars and acidity and increase in Sugar/ Acid ratio in strawberry fruit, thus extended the shelf life, Calcium gluconate and calcium concentration of 1.5% was more effective. Treatment of strawberry fruit with 1.5% calcium from Calcium gluconate source resulted in the highest number of marketable fruit (100%), extended shelf life (10 days) total soluble solid (7.80%) with the minimum weight loss (5.45%). Ascorbic acid content was the highest (35.35 mg/100 g) in fruits treated with the calcium nitrate at 1.0% calcium concentration but was at par with Calcium gluconate. It can be concluded that calcium gluconate at 1.5% concentration is an effective calcium treatment to retain the quality and extend the shelf life of strawberry fruit.

Keywords: Calcium, Concentrations, Fruit, Perishable, Quality, Salts, Sources, Storage, Strawberry