Overview of Food Adulteration from the Biotechnological Perspective

Food Fraud and Food Adulteration

Humans started altering the state and composition of food to extend its longevity and/or improve the taste since prehistoric times. However, the act of adulterating food for economic gain began to emerge over time. During the Middle Ages, some merchants blended numerous cheap substances, such as groundnut shell, pits, seeds, stone and even dust with imported species and sold this adulterated product at a high price. In the food industry, 'food fraud' is generally defined as illegal deception for economic gain (Spink et al., 2019) and these fraudulent activities can pose threats to both consumer confidence, food safety, and public health. Moreover, the reputation of the particular food industry in a specific country/region may be compromised due to the occurrence of food safety incidents or food scandals, which finally lead to economic loss. It is estimated that global trade in fraudulent food may be worth as much as $50 billion per year and affects nearly 10 per cent of all commercially sold food products (Johnson, 2014). Thus, food authentication has been receiving increasing attention from both regulators and the food industry (Everstine et al., 2018).

Briefly, food fraud can be categorised into adulteration (also known as economically motivated adulteration, EMA), tampering, over-run, theft, diverting, simulation and counterfeit (Spink et al., 2019), as Fig. 1 shows. Among all the fraudulent activities, food adulteration breaches food safety legislation, thereby disrupting the food industry the most (Everstine, 2013). Johnson (Johnson, 2014) suggested that among product frauds in the food, beverage, and consumer product industries, food adulteration is the most commonly observed fraudulent activity. Furthermore, public health might be also compromised due to consumption of the adulterated food product. The US Food and Drug Administration (FDA) has defined food adulteration as the "fraudulent, intentional substitution or addition of a substance in a product for the purpose of increasing the apparent value of the product or reducing the cost of its production, i.e., for economic gain" (Johnson, 2014; Spink et al., 2019). Generally, food adulteration can be performed through unapproved enhancement, dilution with a lower-grade ingredient, concealment of damage or contamination, mislabeling of a product or ingredient, substitution of a lower-grade ingredient or failing to disclose the required product information (Bansal et al., 2017; Carcea et al., 2009; Primrose et al., 2010; van Ruth et al., 2017), as Fig. 1 shows.

In 2018, the US Pharmacopeial Convention (USP)'s Food Fraud Database was acquired by Decernis LLC. (http://www.decernis.com), a leading provider of technology and content solutions for product compliance. The number and types of food adulterations collected by Decernis Food Fraud Database until October 2019 and the data is provided in Fig. 2, where

Figure 1. Illustration of food fraud and food adulteration.

Figure 2. The number of records for different food fraud types as shown in Decernis Food Fraud Database till October 2019 from 1980.

Figure 3. Tine number of food adulteration records for each food ingredient group in the "Decernis Food Fraud Database".

the dilution/substitution of food products in multiple ways is the prime fraudulent activity. While the Food Fraud Database has records dating back to the 1800s, the focus of the database is on information since 1980. Although a wide range of analytical/biotechnical methods have been developed and used to detect the presence of food adulterants in the food products, it is still quite challenging to curb food adulteration due to the complexity of the food supply chain and the manufacturing process of food products, increasing international trade and huge economic gain from these illegal deceptions. Thus, fraudulent activities in the common food products, such as bovine milk, beef meat, honey, extra-virgin olive oil and milk powder, etc. are reported quite often, as Fig. 3 and Table 2 show (Uncu et al., 2019).

Note: Gray Market: A market employing irregular but not illegal methods; Theft: Something stolen; Diversion/Parallel Trade: The act or an instance of diverting or straying from a course, activity, or use (Spink and Moyer, 2011).

Table 2. Tine number of total food fraud record, number of incidents and number of inferences during 2010-2019 as recorded in the "Decemis Food Fraud Database"*.

Figure 4. Numbers of publications for food authentication using analytical/biotechnical methods on Scopus.

Accordingly, the numbers of published research works aiming to detect food adulterants using various analytical/biotechnical methods have been increasing fast, as revealed by Fig. 4.