Abstract
Background:
Shrimp is one of the most delicious seafoods, with high nutritive values, including high protein content, omega-3 fatty acids, minerals, and trace elements. However, shrimp are liable for several parasitic infestations.

Aim:
This study examined parasitic infestation in retailed shrimp in Egypt. The histopathological and sensory effects of parasite infestation on shrimp were also examined. The parasite-inhibiting and shrimp-sensory-improving actions of organic acids were also explored.

Methods:
Samples of 200 shrimp were collected from retail markets in Kalyobia Governorate, Egypt. The parasitic infestation of the collected shrimp samples was examined, and the sensory and histopathological changes were investigated. TBA, total volatile base nitrogen (TVBN), and pH were also measured. In a protection trial, the use of a mixture of 1% lactic and acetic acid, peracetic acid, acidified sodium chloride (ASC), and electrolyzed water was tested for their ameliorative effects.

Results:
This investigation showed that parasitic infestation was recorded at 25% (50 of 200 samples). The contaminated shrimp had bleeding, empty stomach, midgut, and pale hepatopancreas. Additional parasite identification indicated that the shrimps were infected with Mysidobdella sp., Microphallid trematode (Microphallus), and Prohemistomum metacercaria. Intestinal sections indicated necrotic enteritis with rounded to oval formations "are parasitic elements" between necrotic and detached enterocytes. Parasite-infested shrimp had lower color, smell, texture, and overall acceptability than noninfested shrimp. Treatment with organic acids, their salts, and electrolyzed acidic water significantly improved sensory properties. All treatments significantly improved TBA, TVBN, and pH toward the acidic side.

Conclusion:
Such acids should be used during shrimp processing to improve their sensory, chemical, and antiparasitological properties.

Key words: Parasites, Shrimp, Organic acids, Chemical quality, Food safety