**2. Food adulteration**

*Mass Spectrometry - Future Perceptions and Applications*

food adulteration have been reported and shown in **Figure 1**.

As shown in **Figure 1**, many food adulterations have been studied in various methods of mass spectroscopy, mainly GC and LC using rapid evaporation ionization spectrometry (REIMS) technique developed initially by Takats et al. [19]. REIMS uses an electrosurgical apparatus that generates surgical smoke after interacting with a solid sample creating ionization and desorption of molecules. Currently, REIMS-based mass spectroscopy has been widely reported for the study of food adulteration, especially for fish and meat adulteration [20, 21]. Another emerging technique is GC-TOF MS mass analyzer for the investigation of a vast number of organic impurities and residues present at the low levels for food quality and safety, surrounding environment, and biological applications [22, 23]. In the analysis of food quality and safety, GC-TOF MS has been utilized to the analysis of in animal-based food origin, such as dioxin-type micro pollutants [24] for the environmental analysis, and GC/GC-TOF MS with negative ionization has been utilized in sediment and fish samples to profile short- and medium-chain

*Some reported work on mass spectrometry development for the investigation of food adulteration.*

always maintained and preserved [7–9].

to \$1.9 Trillion by 2021 [7]. The continuous growth of such market can only happen when consumers' confidence and trust in the halal labels of the food industry are

Food fraud as also known as food adulteration is not a recent issue where some of the fraud have been reported earlier, such as adulteration of formula milk with melamine [10–12], mixing of vehicle oil in oil for human consumption in Spain [13], and addition of sawdust to make white bread [10, 14]. The incident of 2008 affected thousands of babies when their milk powders were adulterated [15]. Another incident following that was meat adulteration when prohibited substances were added to the food [16]. The concern of food quality and safety becomes a major priority of both government ministers and the public due to potential financial loss to the state income and increase consumers' health risks that resulted from breaching the food standards. The food adulteration related to halal and kosher laws is defined as alteration of the original food with pork and its derivatives, such as blood, fat, etc. Lard is a generic ingredient, which is commonly used as a food flavor, mixture, and fat-based blend. Lard has also been reported to be used as an alternative ingredient for adulteration and as a substitute for food-cooking oils, such as butter or margarine. Due to their belief, Muslim communities and Orthodox Jews followers are prohibited to consume lard. Mass spectroscopy (MS) can be used to provide structural details and molecular weight of compounds. Advances of different techniques of MS have emerged significantly. Such advanced techniques utilizing either high resolution mass spectroscopy, that is, GC-MS, or high performance mass spectroscopy, that is, LC-MS, are able to detect more complex compounds with higher accurate identification [17, 18]. Several developments in mass spectrometry for the analysis of the

**88**

**Figure 1.**

Research communities around the world have been continually working on the food adulteration [27]. Water is a simplest and common food adulterant, especially for milk. Water mixing in milk could degrade the nutritional content, change the taste, and modify the color of milk. Other potentially dangerous adulterants, that is, melamine might be added to replicate natural milk, which seriously increase the health risk [28]. Melamine was used to increase the viscosity of the milk and to keep the composition of fat and carbohydrate to be the same as the original. Such milk adulterant had been reported to cause severe health problems, especially to the infants and young-aged children and created an unusual health outbreak in China in 2008. In some cases, expensive milk is often mixed with the cheaper milk. Reported by Calvano et al. [29], milk from unordinary animals, such as buffalo, camel, and yak, was mixed with ordinary animals, such goat or cow milk. For consumers who are very sensitive to certain types of milk, this kind of food adulteration could trigger in them very serious health problem [30].

### **2.1 Lawful food**

It is a compulsory for most religion followers to follow specific compliances in their daily dietary meals. Such laws, for instance in Islam belief, are to avoid some foods in their dietary consumption, which contain pig meat and its derivatives like ham, bacon, sausages, pork, and lard, except in very rare situations. This requirement is referred to Halal food.

Halal food industry is currently growing significantly and is estimated to reach 20% of global food trade market as world population will consist of 30% Muslim followers by the year of 2025 [31]. Other religions also have defined dietary law; for example, Judaism has kashrut for the Jewish to follow, which also forbids the consumption of pig meat and its by-products [32]. For Hindu religion followers, the consumption of beef and its derivative is not permissible [33]. Many food manufacturers violate the requirement not to practice food fraud that is mostly due to cheap substitute materials.

Muslims and Jews are some of those religious groups that require diet intake restrictions, as they adhere to halal and kosher laws [34, 35], respectively. Although halal and kosher laws have similarities, that is, forbidding consumption of pork and derivatives, blood, etc., they have differences, such as kosher does not forbid alcohol and kosher forbids consumptions of animals that do not chew cud and have cloves, etc. [34]. Although halal and kosher are different, both laws severely forbid the consumption of pork and its derivatives such as lard [34]. Lard is pig fat derived from its adipose tissue and is often used in food production as an emulsion, shortening, or as a substitute to butter, margarine, or cooking oils. The identification of non-halal meat due to lard adulteration is of high significance. Despite many reported work that have been performed to investigate the fingerprint for noncompliance of halal food, such as lard or pig meat [6, 34, 35], the identification of biomarker for non-halal food is still in the early stages.
