Applying morphologic techniques to evaluate hotdogs: what is in the hotdogs we eat?

doi:10.1016/j.anndiagpath.2007.04.012

Annals of Diagnostic Pathology

Volume 12, Issue 2, April 2008, Pages 98-102

https://doi.org/10.1016/j.anndiagpath.2007.04.012 Get rights and content

Abstract

Americans consume billions of hotdogs per year resulting in more than a billion dollars in retail sales. Package labels typically list some type of meat as the primary ingredient. The purpose of this study is to assess the meat and water content of several hotdog brands to determine if the package labels are accurate. Eight brands of hotdogs were evaluated for water content by weight. A variety of routine techniques in surgical pathology including routine light microscopy with hematoxylin-eosin–stained sections, special staining, immunohistochemistry, and electron microscopy were used to assess for meat content and for other recognizable components. Package labels indicated that the top-listed ingredient in all 8 brands was meat; the second listed ingredient was water (n = 6) and another type of meat (n = 2). Water comprised 44% to 69% (median, 57%) of the total weight. Meat content determined by microscopic cross-section analysis ranged from 2.9% to 21.2% (median, 5.7%). The cost per hotdog ($0.12-$0.42) roughly correlated with meat content. A variety of tissues were observed besides skeletal muscle including bone (n = 8), collagen (n = 8), blood vessels (n = 8), plant material (n = 8), peripheral nerve (n = 7), adipose (n = 5), cartilage (n = 4), and skin (n = 1). Glial fibrillary acidic protein immunostaining was not observed in any of the hotdogs. Lipid content on oil red O staining was graded as moderate in 3 hotdogs and marked in 5 hotdogs. Electron microscopy showed recognizable skeletal muscle with evidence of degenerative changes. In conclusion, hotdog ingredient labels are misleading; most brands are more than 50% water by weight. The amount of meat (skeletal muscle) in most brands comprised less than 10% of the cross-sectional surface area. More expensive brands generally had more meat. All hotdogs contained other tissue types (bone and cartilage) not related to skeletal muscle; brain tissue was not present.

Introduction

It is estimated that Americans consume approximately 20 000 million hotdogs in a single year; this accounts for more than 1500 million dollars in retail sales [1]. Hotdogs are clearly big business. It is widely presumed that hotdogs are primarily composed of meat; most package labels list some type of meat as the first ingredient.

The purpose of this study was to use typical morphologically based techniques that are commonly used in the evaluation of tissue in the practice of surgical pathology (ie, routine light microscopy with hematoxylin-eosin–stained sections, special staining, immunohistochemistry, and electron microscopy) to examine the histology of several hotdog brands to assess the accuracy of the package labeling.

Section snippets

Methods and materials

Eight different brands of hotdogs were purchased from local grocery stores. The brands were labeled franks (n = 3), turkey franks (n = 2), beef frank (n = 2), and hotdogs (n = 1). Brands were coded from A to H. Information obtained from the packaging included the top-listed ingredients, price per hotdog, amount of fat per hotdog, and amount of protein per hotdog.

The percentage of water content was determined for each hotdog by weighing a portion of each dog, grinding it and allowing the

Results

Eight different brands of commercially available hotdogs were evaluated. Table 1 summarizes information obtained from the package label for each brand. The price per hotdog ranged from $0.12 to $0.42 (median, $0.29). The first ingredient listed on the package label for the hotdogs was a type of meat in all 8 brands. The second ingredient listed was water in 6 brands and another meat type in 2 brands. The protein content (presumably correlating with the amount of protein-containing tissue in

Discussion

The manufacturing of hotdogs is regulated by federal standards in the United States. According to regulations, hotdogs should not contain more than 30% fat, 10% water, or a combination of 40% fat and water [2]. Up to 5.5% of nonmeat binders and extenders including dry milk, cereal, or soy protein may be added [2]. Guidelines recommend that they should consist of no less than 15% of raw skeletal muscle (or meat) or meat byproducts [2]. Turkey or chicken franks may also contain skin and fat in

Acknowledgment

The authors thank Richard Kawolics for his help with this project.

References (5)

National Hot Dog and Sausage Council. Website:http://www.hot-dog.org. Accessed November 20,...
Hot Dogs and Food Safety. United States Department of Agriculture Food Safety and Inspection Service....

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Original ContributionsApplying morphologic techniques to evaluate hotdogs: what is in the hotdogs we eat?