MAPPING HALAL COSMETICS RESEARCH: A BIBLIOMETRIC ANALYSIS

The study of halal cosmetics has been growing exponentially in the last few years. Numerous studies pertaining to halal cosmetics have been conducted. The main objective of this study is to visualize trends in halal cosmetics research from 2006 to 2020. This encompasses the assessment of halal cosmetics research, collaboration networks, and publication patterns across various fields. We aim to provide a systematic overview and historic context, as well as distinguish future trends in research on consumers’ perception of halal cosmetics. This study conducted a bibliometric analysis of research related to halal cosmetics. Data from 2006 to 2020 related to halal cosmetics were extracted from the Scopus database, providing a sample of 104 documents. The documents were then examined using the bibliographic network visualization instrument VOSviewer and R for text mining and the findings were presented in the form of a conceptual structure map and word clouds. We identified the most productive authors, journals, institutions, and countries. The results showed that Malaysia and Indonesia are the overall leaders in publications. These findings will provide scholars a comprehension of the halal cosmetics field and act as a guide for future research. Finally, it enables us to identify the extent of globalization in the field, leading topics, and potential gaps.


Introduction
The study of halal cosmetics has been growing exponentially in the last few years. Numerous studies pertaining to halal cosmetics have been conducted. The Arabic word halal means "permissible" or "lawful," while its opposite, haram, means "prohibited" or "unlawful" (Hanapi and Khairuldin, 2017). The general understanding is that halal products (especially foods) should not be contaminated with pork or alcohol and that livestock should be slaughtered following Islamic Sharia law. However, as stated in other literature Alzeer et al. (2017) halal does not solely refer to foods but may extend to all consumables, such as toiletries, pharmaceuticals, cosmetics, and services, including finance, investments, and business.
A cosmetic product is "any substance or preparation intended to be placed in contact with various external parts of the human body (epidermis, hair system, nails, lips, and external genital organs) or with teeth and the mucous membranes of the oral cavity, with a view exclusively or mainly to cleaning them, perfuming them, changing their appearance, correcting body odours, protecting them, or keeping them in good condition" (NPRA, 2017). A cosmetic product is considered halal if the following conditions are met: (a) does not comprise or contain any human parts or ingredients derived thereof; (b) does not comprise of or contain any parts or substances derived from animals forbidden to Muslims by Shariah law to use or to consume or from halal animals which are not slaughtered according to Shariah law; (c) does not contain any materials or genetically modified organisms (GMO) which are decreed as najis according to Shariah law; (d) is not prepared, processed, manufactured, or stored using any equipment that is contaminated with things that are najis according to Shariah law; (e) during its preparation, processing, or manufacturing, the product is not in contact and physically segregated from any materials that do not meet the requirements stated in items (a), (b), (c), or (d); and (f) does not harm the consumer or the user (Jusoh et al., 2016).
Halal cosmetic products must be certified as halal by the relevant certification bodies. In Malaysia, for example, the Department of Islamic Development Malaysia (JAKIM) is responsible for providing halal certification. For halal products coming from outside Malaysia, the department requires reputable and credible foreign halal certification bodies to act as JAKIM representatives and verify the halal status of raw materials and finished products with responsibility and integrity. In addition, JAKIM has published a list of "The Recognised Foreign Halal Certification Bodies and Authorities." This list is renewed according to the latest updates based on JAKIM audits. (At the time of writing, the list was last updated December 1, 2020.) The list is important as a recognition of the capability of the foreign halal certification bodies that comply with Malaysian procedures and guidelines.
Halal certification is important because it allows members of the public to be confident that cosmetic products are halal. According to Ali et al. (2016) halal-certified products are more ethical, eco-friendly, organic, and green, with a non-exploitative and humanitarian approach. This viewpoint is further substantiated by Bhatia and Jain (2013) who expressed that halal products are more natural and ecofriendlier. Aoun and Tournois (2015) stated that halal certification and ingredient certification increase ethical standards and support brands that, through halal certification, are fighting against cruelty and environmental pollution and are establishing green marketing. Thus far, reviews have rarely taken stock of halal cosmetics research.
The main objective of this study is to visualize trends in halal cosmetics research from 2006 to 2020. This encompasses the assessment of halal cosmetics research, collaboration networks, and publication patterns across various fields. We aim to provide a systematic overview and historic context, as well as distinguish future trends in research on consumers' perception of halal cosmetics. Furthermore, this analysis allows us to identify the most impactful articles; the most productive authors, journals, sources, countries, and institutions; and patterns of cooperation among them. Finally, it enables us to identify the extent of globalization in the field, leading topics, and potential gaps (van Nunen et al., 2018).

Source of data
This study considers data derived from the publications indexed in the Scopus database to perform the bibliometric analysis. The Scopus database offers a greater selection of journals than other scientific databases, such as the Web of Science (WoS). The Scopus database provides access to more than 21,500 peer-reviewed journals, 83,000 conference events, 530 book series, and 120,000 books (To and Yu, 2020). To create a representative set of documents for analysis, the following search string was used: TI-TLE-ABS-KEY: ("halal cosmetic").

Analytical Method
This study analyzes all documents on the subject of halal cosmetics found in the Scopus database. The resulting 104 scientific documents indexed in the Scopus database include articles, books, book chapters, conference papers, notes, reviews, and short surveys dating from 2006 to 2020. The dataset was built in three stages. First, we conducted a descriptive analysis of the data. Second, following earlier bibliometric surveys e.g., Batistič et al. (2017) we looked for the term "halal cosmetic" in the title, abstract, or keywords for content analysis. Third, we visualized clusters using VOS viewer and R for text mining and presented density maps or network visualizations where the size of the circle for each data point indicates the number of citations, the color indicates the cluster the publication be-longs to, and the lines between the circles indicate the relative link strength (van Eck and Waltman, 2010). Table 1 shows that from 2006 to 2020, there were 104 documents pertaining to halal cosmetics. Articles are the most common document type with 80 results, followed by conference papers with 10 results. Analysis by year   Table 2 indicate the most published and impactful authors on halal cosmetics. The progressively intensive review given in Table 2 shows that there are 20 most productive authors in this field. 2011 marked the first year of publication in the field, with a gap of six years before the next publications. The co-authorship and collaboration network is shown in Figure 2. This figure presents the authors most often co-cited and sheds light on the collaboration network of authors. According to the connection network, A. Rohman has the most extensive and wide-ranging network and is also one of the most cited authors after A.H. Ngah, followed by N.A.B. Abdullah, S. Ainin, M.E. Ali, and P. Grag.

Analysis by journal or source
The journals or sources that most often publish halal cosmetic research is summarized in Table 3. From Table 3 Figure 4a, it can be seen that the international collaboration between countries on halal cosmetic research is significant. The network with nodes demonstrates that the strongest links are between Malaysia and Indonesia. Notable new contributions to the field come from India, the Netherlands, the US, Thailand, the United Arab Emirates, etc. Through authorship patterns, collaboration networks across countries are shown in Figure 4b. There are four main clusters with nodes indicated by light turquoise, purple, yellow, and dark blue. The size of the node indicates the relative frequency of publication. Among the collaborating countries, Malaysia has a strong collaboration with India, the Netherlands, and Bangladesh. Indonesia has a strong network with New Zealand and Norway. The countries in the third cluster include Japan, the Philippines, and Thailand. The UAE has a strong network in cluster four with Brunei and France.

Analysis by Organization
The most productive organizations in the field of halal cosmetic research are shown in Figure 5. The leading organizations are Universiti Malaya and Universiti Putra Malaysia with 13 and 11 articles, respectively, followed by Universitas Gadjah Mada and Universiti Kebangsaan Malaysia with 6 articles each. The International Islamic University Malaysia and Universiti Sains Malaysia are next most productive with 5 articles each.

Keyword Co-occurrence Analysis
To identify developing themes and cutting-edge research frontiers in halal cosmetics over time, we used keyword co-occurrence analysis. It is important to note that this analysis shows the frequency with which certain keywords appear next to others in published documents. Considering a wide perspective, Figures 6a and 6b show the word treemap and word cloud resulting from R text analysis.

Figure 6a Word tree map
Major topics in halal cosmetics research during the study period are represented by the nodes with high co-occurrence frequencies. Figure 6a depicts the most important keywords used in the articles through a treemap displaying data as a set of nested rectangles. It reveals the hierarchical datasets within the data, revealing natural groupings of words in halal cosmetics research. The node size and color patterns represent correlation and relevance, respectively. From Figures 6a, and 6b, it can be seen that the most common keyword is "halal cosmetics," followed by "halal," "religiosity," "purchase intention," and "cosmetics."

Conceptual Structure Mapping
A conceptual framework was developed through textual analysis utilizing the co-occurrence of words. Words for analysis can be selected by extracting terms from abstracts or titles, author keywords, and KeyWords Plus. To draw a conceptual structure map of the field the analysis was carried out using R software. Figure 7 shows the conceptual structure map with three clusters marked in green, red, and blue. The red cluster contains the most keywords (e.g., halal cosmetic, cosmetic products, personal care, halal authentication, halal certification, Islamic markets, and others), followed by the blue cluster (e.g., consumer behavior, branding, the Muslim consumer, Islamic marketing, halal market, and Islam).

Discussion
In terms of document type (Table 1), it was found that nearly 77% of the publications on halal cosmetics were in journals. This is probably driven by higher learning institutions' emphasis on publication in academic journals rather than other types of documents, such as conference proceedings or chapters in books. This may be due to the assumption that a journal article goes through a more rigorous peer review process then the other types of documents. A. Rohman is the author with the highest number of publications (Table 2). This is because Rohman has been publishing on issues related to halal cosmetics since 2011, while the other authors studied, such as Ngah, first published on the topic in 2017; Abdinagoro started in 2018, and Ainin in 2019. Table  2 also show that Ngah was the author with the highest number of citations. This may be due to his area of focus. He focused on halal transportation and the adoption of halal warehousing practices among pharmaceutical and cosmetics manufacturers, whereas Rohman's work is mostly related to halal authentication.
The analysis in Table 3 shows that the greatest number of publications related to halal cosmetics are in the Journal of Islamic Marketing. This is not surprising, as the name of the journal reflects that the contents are related to Islamic principles such as halal. Besides this journal, there are two other journals, the Global Journal Al-Thaqafah and Al-Jami'ah, whose titles demonstrate their focus on Islamic issues. It can be concluded that future work on halal cosmetics should refer to articles in the Journal of Islamic Marketing.
In addition, As the keyword used to extract the data was "halal cosmetics," it was expected that the highest occurrence among the nodes shown in Figures 6a and 6b would be "halal cosmetics." This was true, and the keyword was followed by the terms "halal," "religiosity," "purchase intention," and "cosmetics." This shows that, in discussing halal cosmetics, more researchers are focusing on religiosity as a contributing factor in consumers' purchase intentions regarding halal cosmetics. In addition, the structure map of the field analysis ( Figure 7) illustrated that in discussing halal cosmetics authors tend to focus on issues related to marketing (such as consumer behavior, branding, Muslim consumer, Islamic marketing, halal market) and halal standard (such as halal authentication and halal certification). These results imply that halal cosmetics have been studied from various perspectives and subject areas hence the increasing number of publications related to it.

Conclusion
Research on halal cosmetics shows fairly defined trends that continue to grow into various disciplines in several countries. Halal cosmetics research has come a long way over the last decade in developing a shared body of thought to serve as the basis for the future consideration of halal cosmetics as an academic discipline. This study discloses some outcomes from the perspective of academic thought that can guide scholars in the field of halal cosmetics to observe underlying dynamics in a more refined way, with substantial implications on many related areas of research. By using bibliometric analysis on research in the field of halal cosmetics, we were able to visualize and trace the evolution of the field and distinguish the most productive authors, years, journals, articles, countries, and institutions. Compared with research on halal food, research on halal cosmetics is relatively new, hence it is no surprise that the field is still in its infancy (Sugibayashi et al., 2019). The development of halal cosmetics research could also be attributed to the demand for halal cosmetic products among 2.4 billion Muslim consumers around the world. Existing literature on halal cosmetics provides essential guidance to researchers or academics seeking to explore this subject further, whether in material science, such as finding new production techniques, or in social science, such as in governance, consumer-based aspects, etc. As with any other study, this study has some limitations. First, the study focuses only on the keyword "halal cosmetics;" future studies might widen the scope to include synonyms, such as "Shariacompliant cosmetics" and "Muslim-friendly cosmetics." Two, the study reviews only articles published in journals contained within the SCOPUS database. Future studies should include other online databases to achieve more comprehensive outcomes and build on the contribution of this article to our understanding of the field.