The effect of the food grade additive phosphate pre-treatment prior to the industrial cooking process in the quality of cooked peeled shrimp (Litopenaeus vannamei).

BACKGROUND: The food-grade additive phosphates have been highlighted as a potential alternative as a humectant agent to avoid large yield losses. Thus, the combined effect of phosphate with industrial cooking on shrimp quality was evaluated. Phosphate concentration (3% and 5%) and contact time (30 and 60 min) were evaluated as a pre-treatment to the industrial cooking of the peeled shrimp, in a shrimp processing plant. The yield process (%), physical quality [pH, color, texture, and water-holding capacity (WHC)] and chemical quality [moisture, protein, moisture/protein ratio, phosphate, and sodium] were also evaluated. RESULTS: Our results showed that the food grade phosphates treatment showed a satisfactory effect on reduction of the weight loss, increase of the WHC (after cooking and posterior thawing), increase of the M/P ratio, improvement of the texture, decrease in the meat coloring, increase of the pH (0.3 to 0.5 units), but no affect on the shrimp overall quality (cooking yield, texture, WHC). Therefore, the residual phosphate and sodium contents increased proportionally with the concentration and time of contact with the additives, and slightly above the legal phosphate limit allowed. CONCLUSION: We observed that the phosphate used as a pre-treatment of cooking step in shrimp plant processing improves the product quality, however, this treatment must be realized in accordance with the current federal legislation in each country. © 2018 Society of Chemical Industry.

Oxygen release compound as a chemical treatment for nutrient rich estuary sediments and water.

The objectives of this work were: (i) to evaluate the efficacy of Oxygen Release Compound (ORC), oxygen providing agent that enhance the oxidation of organic matter in fresh water, marine water, and sediment; and (ii) to explore the potential aquatic toxicity that might be generated due to its use. A bench scale laboratory experiments were conducted using five different water sources (2 freshwater, 2 marine water and a deionised water). During the assay, flasks of 1 L capacity were dosed with artificial sediment and ORC and kept at room temperature for 10 days. Temperature, pH, DO, UV254, TOC and Mg were periodically measured. The potential aquatic toxicity that might be generated as a by-product of ORC use was performed. The experimental results reveal that ORC is indeed effective in releasing oxygen over a long period of time and it is also effective for the remediation of natural waters enriched with organic matter. The toxicity test shows that ORC treatment did not create any biological toxicity in freshwater samples (IC50<1 Toxicity Unit-TU). However, marine water samples reveal a high toxicity and had IC50>1 TU. The study proves that ORC was an appropriate technology that can safely be used to treat natural waters enriched with nutrient and natural organic matter.