1204 Journal of Food Protection, Vol. 45, No. 13, Pages 1204-1207 (November 1982) Copyright~. International Association of Milk, Food, and Environmental Sanitarians Mites and Other Filth in Dried Shrimp Imported into the United States From the Orient ALAN R. OLSEN Food and Drug Administration, Los Angeles, California 90015 Downloaded from http://meridian.allenpress.com/jfp/article-pdf/45/13/1204/1654958/0362-028x-45_13_1204.pdf by guest on 30 September 2021 (Received for publication April 26, 1982) ABSTRACT MATERIALS AND METHODS Fifty samples of dried shrimp imported into the United States From December 1980 through July 1981, 50 samples of small (2-5 em) from the Orient were examined for filth contamination. Twenty­ imported dried shrimps were examined for filth contamination. The sam­ one samples (42%) contained significant filth, including insect ples, drawn from separate lots of product offered for entry into the U.S. at ports in California and Hawaii, consisted of dried shrimp with few or fragments, whole insects, mites, rodent hairs and feather frag­ no added ingredients. Several varieties of shrimp were sampled, but be­ of occurrence was tabulated for each type of ments. Frequency cause of the desiccated nature of the product, exact taxonomic identities filth. Mite contaminants included Lardoglyphus konoi (Sasa and could not be made. Collected samples were preserved at refrigeration Asanuma) (Acarina:Acaridae) and house dust mites (Pyrog­ temperature (2°C) until they were examined at an FDA laboratory in Los lyphidae). Angeles or San Francisco. Each sample was separately examined by the Wildman trap flask tech­ nique (2). Since no official method of analysis for light filth in dried shrimp is available, the methodology varied between samples as did the amount of product examined per sample. The original containers were a variety of bulk and shelf-sized sealed plastic packages, which were in­ spected for damage or defects. Only intact packages were included in this study, and the contaminants found were assumed to be present in the Whole small dried shrimps are gaining wide acceptance products at the time of export. as an imported specialty food in the United States. Many dried shrimp products are imported from the Orient through ports of entry in California, where they are in­ RESULTS spected by the U.S. Food and Drug Administration (FDA) before release for sale to the American public. FDA is re­ Of the 50 samples examined, 21 (42%) were contami­ sponsible for intercepting imported foods which are con­ nated with filth. Of these samples, which were produced in taminated with filth from arthropod and vertebrate pests of 8 different geographic localities, at least one sample from stored products. However, very little is known about the each locality was contaminated. The area from which sam­ incidence and kinds of pests which may contaminate dried ples were received and the number of samples containing shrimp. The object of this study was to determine the inci­ filth/number of samples collected were as follows: Hong dence and identity of the filth contaminants in dried shrimp Kong 2!15, Indonesia 2/2, Japan 1/10, Malaysia 1/1, entering the U.S. through California ports. Philippine Islands 2/2, Singapore 3/4, Taiwan 517 and The mites (Acari) which were frequently found as conta­ Thailand 5/9. The contaminants included insect fragments, minants of dried shrimp were primarily stored-product or whole insects, mites, feather fragments and rodent hairs. other synanthropic species; their presence in food results Table 1 presents the distribution of the types of filth from insanitary practices or conditions and could contrib­ found. Nineteen samples (38%) contained two groups of ute significantly toward the regulatory actions taken by mites: the "acarid" (superfamily Acaroidea) and the house FDA against these products. Because the Agency recog­ dust mites (family Pyroglyphidae). Other types of filth nizes the need for a full understanding of acarology as re­ found were whole booklice (Psocoptera:Liposcelidae); lated to the enforcement of Federal food sanitation statutes whole dermestid larvae and dermestid fragments (family (4), the traditional categories of mite contaminants in foods Dermestidae:Dermestes spp.); fragments and whole speci­ are being reevaluated with regard to their significance in mens of storage beetles other than dermestids, including human health and sanitation. It is hoped that this study will flour beetles (Tenebrionidae:Tribolium spp.), grain beetles aid food sanitation control workers to detect and evaluate (Cucujidae:Cryptolestes spp. and Oryzaephilus sp.) and mite contamination of dried shrimp. others (Trogositidae:Tenebroides sp. and Lophocateres JOURNAL OF FOOD PROTECTION, VOL. 45, NOVEMBER 1982 FILTH IN IMPORTED DRIED SHRIMP 1205 sp.); fly (Diptera) filth and vertebrate filth (feather frag­ TABLE 2. Frequency distribution of contaminants in "stan- ments and rodent hairs). No filth was found in 29 of the 50 dard" samples (58%). No. of No. of %Samples Cumulative% contaminants TABLE 1 . Distribution of types of filth found in samples of im­ dried 0 29 58 58 No. of 1-100 9 18 76 Insect fragments 21 42 101-200 6 12 88 "Acarid" mites 13 26 201-300 4 8 96 House dust mites 8 16 301-400 1 2 98 Whole insects 11 22 401-500 0 0 98 Fly 9 18 501-600 2 100 Vertebrae 15 30 Mites Downloaded from http://meridian.allenpress.com/jfp/article-pdf/45/13/1204/1654958/0362-028x-45_13_1204.pdf by guest on 30 September 2021 No filth found 29 58 0 31 62 62 1 -10 6 12 74 10 -102 5 10 84 Table 2 presents a frequency distribution for contamin­ 102-103 3 6 90 ants, of which insect fragments were the most frequently 103-104 2 4 94 encountered. The numbers of insect fragments are based on >104 3 6 100 a sample size of 3600 g of dried shrimp. Results from three Feather fragments samples of different sizes (1800 g, 3007 g and 3744 g) were extrapolated to fit this "standard" size. The numbers 0 36 72 72 of insect fragments ranged from 0 to 576, with a mean in­ I 5 10 82 sect fragment count of 63.3/3600 g. Most insect fragments 2 2 4 86 1 2 88 were ants and various flying insects, such as thrips and 3 4 2 4 92 aphids. The storage beetles, including dermestids, contrib­ 6 2 94 uted fewer than 25 fragments to any particular sample. 8 2 96 There is no apparent explanation for the presence of insect 12 2 98a fragments in whole dried shrimp, except that the fragments 21 2 100 may have originated from whole insect contaminants Rodent hairs which were fragmented by manipulation of the product during the drying process. 0 40 80 80 The number of whole mites ranged from 0 to more than 1 2 82 2 2 4 86 40,000. Mites were found in 38% of the samples with a 3 2 4 90 mean number of 1437/3600 g. Of these samples, 84% con­ 4 2 92 tained fewer than 100 mites. The most abundant mite was 5 2 94 a dried seafood pest, Lardoglyphus konoi (Sasa and 6 2 96 Asanuma) (Acaridae), which was found in 8 samples of 8 2 98 dried shrimp in numbers ranging from 200 to 40,000. 12 2 100 Suidasia pontifica Oudemans (Saproglyphidae), a cos­ Whole insects mopolitan pest of stored foods, was found in 6 samples and 0 39 78 78 ranged from 27 to 300. House dust mites of the genera 2 4 82 Euroglyphus and Dermatophagoides (Pyroglyphidae) were 2 0 0 82 found in 8 samples and ranged from 1 to 67. Other stored­ 3 2 84 product mites found were the brownlegged grain mite, 4 1 2 86 Aleuroglyphus ovatus (Troupeau) (Acaridae), and the mold 5 0 0 86 mite, Tyrophagus putrescentiae Schrank (Acaridae), with 6-10 2 4 90 10 and 4 mites, respectively, isolated from different sam­ 11-15 3 6 96 ples. One sample from Thailand contained 68 carcasses of >15 2 4 100 an intertidal or aquatic mite (probably family Halacaridae). asample of 1800 g containing 6 feather fragments. Twenty-eight percent of the samples contained feather contaminants; feather fragments ranged from 0 to 21, with 1.5 as the mean number. Feather contamination suggests would most likely be insanitary handling and processing that the product was exposed to birds during harvesting or practices. drying. The mean number of whole insects was 2.1, with a Twenty percent of the samples contained rodent hairs; range of 0 to 24. Eleven samples (22%) contained whole rodent hair contamination ranged from 0 to 12, with 0.9 as insects, including booklice (Psocoptera:Liposcelidae), stor­ the mean number. Since rodents do not occur in the age beetles, thrips, aphids, flies, rove beetles shrimp's natural habitat, the source of this contaminant (Staphylinidae) and a spider. JOURNAL OF FOOD PROTECTION, VOL. 45, NOVEMBER 1982 1206 OLSEN DISCUSSION Countries with distributional records for L. konoi in­ clude England, Germany, India, Japan (3), Korea (1), Mites were the most prevalent pests of the dried shrimps Kenya, United States (R. Smiley, personal communica­ examined. Although these mites are unfamiliar to many tion) and Taiwan (5). New records resulting from this food sanitation control workers, they are generally com­ study on dried shrimp include Indonesia, Malaysia, Philip­ mensal or synanthropic species, whose presence in a food pine Islands and Singapore. Lardoglyphus konoi was also product is related to insanitary manufacturing or storage found in one sample of dried anchovies (20,000 in 900 g) practices. Hughes (3) reviews the morphology and biology from the Philippine Islands. An immature stage, the of most of the species of mites found in dried shrimp.