A New Procedure for Marinating Fresh Anchovies and Ensuring the Rapid Destruction of Anisakis Larvae

Abstract

The consumption of marinated anchovies is the main route of transmission of anisakiasis in Spain. Because this country is one of the world's major tourist destinations, this traditional food also poses a potential health risk to millions of foreign visitors. Anisakis larvae are not destroyed by the traditional marinating procedure, and alternative methods, such as long-term storage in brine, freezing, or hydrostatic pressure treatment, all present major difficulties. In this study, we used high food-grade acetic acid concentrations (10, 20, 30, and 40% [vol/vol] in line with the quantum satis rule) to destroy these larvae rapidly, and we report data on the survival of Anisakis larvae exposed directly to different marinades and when the larvae are placed under the fish musculature. The percentage of salt and acetic acid in the fish tissue water phase was also determined. A marinating procedure is proposed that ensures the rapid death of Anisakis through the use of strong acetic acid concentrations. Posttreatment washes with water reduce these to levels acceptable to consumers. The sensory characteristics of the product were shown to be satisfactory. The actual selection of an acetic acid concentration for marinating depends on costs and the processing time available. The physiological stress of the larvae exposed to the different marinades was determined by measuring the levels of their stress proteins. The latter are good indicators of injury and might reflect the infectivity of larvae. In addition, we also used a rat model to determine the infectivity of larvae considered microscopically dead.

Research Note. Prevalence, protein analysis and possible preventive measures against zoonotic anisakid larvae isolated from marine Atherina fish

“…Extending the incubation time to 72 hrs resulted in death of all the exposed larvae (100 %) ( Table 2). There are some similarities between our results and that found in other studies (Sanchez-Monsalvez et al, 2005). They argued that further washing of marinated fi sh would reduce the acid concentration to a level that is acceptable for the consumers.…”

Assessing the risk of an emerging zoonosis of worldwide concern: anisakiasis

“…Anisakis spp. can survive the traditional Spanish marinating procedure, even though its survival can be compromised by increasing the concentration of salt, acetic acid and storage time in brine44. In vitro studies have demonstrated that saline extracts from garlic can be destructive to Anisakis spp 53…”

“…can survive the typical conditions experienced in the traditional preparation of anchovies in vinegar44, even though it is unknown what proportion of parasites is viable in freshly caught anchovy. In the first instance, the QRA model assumed that all Anisakis spp.…”

Effect of Allyl Isothiocyanate against Anisakis Larvae during the Anchovy Marinating Process

“…In the last decade, some innovative techniques have been introduced for inactivation of anisakid larvae in fish products, although methods such as irradiation (31) and high hydrostatic pressure (8,22) can have a negative effect on the sensorial parameters of the product. Sanchez-Monsalvez et al (30) proposed a new marinating technique based on 5 days at 4°C in a marinade containing 12% salt and 6% acetic acid followed by posttreatment washes to reduce the acetic acid concentrations to levels acceptable to consumers. Under these conditions, the death of all parasites present in the anchovy fillets was observed after 13 days at 4°C.…”