Data on the chemical properties of commercial fish sauce products

This data article reports on the chemical properties of commercial fish sauce products associated with the fish sauce taste and flavor. All products were analyzed in triplicate. Dried solid content was analyzed by moisture analyzer. Fish sauce salinity was determined by a salt meter. pH was measured using a pH meter. The acidity was determined using a titration assay. Amino nitrogen and total nitrogen were evaluated using a titration assay and Combustion-type nitrogen analyzer, respectively. The analyzed products originated from Japan, Thailand, Vietnam, China, the Philippines, and Italy. Data on the chemical properties of the products are provided in table format in the current article.


Specifications
Data accessibility All data are presented in this article

Value of the data
The presented data on the chemical properties of 46 commercially available fish sauce products from Japan, Thailand, Vietnam, China, the Philippines, and Italy may be used as a reference for culinary studies of the fish sauces and related products.
The data will be useful for nutritional assessment of the fish sauce products based on the chemical properties of these products.
The presented data will allow the prediction of consumer preferences with regard to fish sauce products in each country.

Data
Fish sauce is a popular condiment on account of its distinctive flavor and taste. It is obtained by mixing fish material with salt, which is subsequently fermented under natural conditions [1]. In Japan, fish sauce is mainly used as a condiment in "Nabe" cuisine, a Japanese-style stew [1]. Among the Southeastern Asian countries, the widest variety of fermented fish products is found in Thailand [2]. In Vietnam, the fish sauce is used for dipping in a wide variety of dishes [3]. In China, fish sauce is used as a substitute for soy sauce in some dishes [1]. Patis, a Philippine fish sauce, is used in a citrus fruit soup [2]. The Italian fish sauce is based on Garum, which is the earliest reported fish sauce highly appreciated in the Roman era [4]. In general, fish sauces have a predominantly salty and umami taste, and distinctive flavor [5]. Therefore, data on the following were generated: fish sauce salinity, determining the salty taste; acidity, which roughly reflects the organic acids associated with the distinctive flavor and sour taste of the fish sauce; and nitrogen, representing the amino acids associated with the umami taste. Data on the chemical properties of 46 commercial fish sauce products produced in several countries (Japan, Thailand, Vietnam, China, the Philippines, and Italy) are presented. The origin and materials of the analyzed fish sauce products are provided in (Table 1). The data on their dried solid content, salinity, pH, acidity, and nitrogen content are shown in Table 2.

Design
Data are presented for the following numbers of different commercial fish sauce products: 30 sauces produced in Japan; 11 sauces from Thailand; two sauces from Vietnam; and one from each of the Philippines, China, and Italy (Table 1). For each fish sauce product, analysis was performed in triplicate.

Materials
Data for 46 fish sauces are presented. The ingredients of each product described on the product label are summarized in Table 1. For the analysis, the products were assigned product IDs, as follows: J1-J30 for the 30 Japanese products; T1-T11 for the Thai products; V1 and V2 for the Vietnamese products; and P1, C1, and I1 for the Filipino, Chinese, and Italian products, respectively. All fish sauce products were purchased in a local market in Tokyo, Fukuoka, or Abashiri (Japan).

Solid contents assay
To determine the dried solid content of the fish sauce products, ca. 2 g of fish sauce sample was applied to a moisture analyzer (MX-50; A&D, Japan). The measurements were conducted at 130°C for 20 min, as described in Ref. [6].

Salinity and pH measurements
The salinity and pH of the fish sauce products were determined using a salt meter (B-721; HORIBA, Japan) and a pH meter (D-52; HORIBA), respectively.

Total acidity assay
Total acidity was determined by a titration assay. Briefly, 10 g of fish sauce samples were diluted up to 100 mL with distilled water. Acid content in 10 mL of the diluted sample was determined by titration with 0.1 M NaOH, with 1% (w/v) phenolphthalein solution as a pH indicator.

Amino acid content determination
The total nitrogen content was determined using SUMIGRAPH NC-220F analyzer (Sumika Chemical Analysis Service, Japan) [7].
Amino nitrogen content was determined using the formol titration method [8]. Briefly, 5 mL of the fish sauce sample was diluted up to 250 mL with distilled water. For the first titration, all of the diluted sample was titrated to pH 8.5 with 0.01 M NaOH. For the second titration, 20 mL of formaldehyde solution (pH 8.5) was added to the diluted sample, and then titrated to pH 8.5 with 0.1 M NaOH. The volume of base consumed in the first and second titration was used for calculating the amino nitrogen content [8].
The amino nitrogen to total nitrogen ratio, i.e., a value of amino nitrogen divided by total nitrogen, was used as an index of protein-to-amino acid conversion rate.