Sustainable halal food supply chain management in a small rentier halal market

Purpose – ThereislimitedknowledgeofthesustainablehalalfoodsupplymanagementinBruneiDarussalam (Brunei), although it is reputable in the halal economy and advocates the United Nations (UN) Sustainable Development Goals (SDGs). Therefore, this paper highlights issues faced in a small, rentier halal market and proposessustainablesupplychainmanagement(SSCM)initiativesforhalal-certifiedfoodcompaniesinBrunei. Design/methodology/approach – This paperdraws datafrom published academicresearchand employsa normative and narrative assessment of SSCM and halal supply chain literature. Findings – Four normative SSCM initiatives and propositions that could be implemented by Brunei halal-certified food businesses in achieving the SDGs are highlighted: responsible sourcing, environmental purchasing, sustainable packaging and green transportation. Practical implications – This viewpoint paper provides a basis for achieving the “ Brunei Vision 2035 ” throughasustainablesupplychainlensthatmayincreasewell-beinganddevelopaproductiveandsustainable economy.ItalsolaysafoundationforrealisingtheSDGs,specificallyGoal12ofSustainableConsumptionandProduction. Originality/value – The dedicated attention to smaller halal markets, such as Brunei, would enrich the literature, reveal unforeseen issues or address gaps in the domains of SSCM and halal food supply chains.


Introduction
Halal, an Arabic word, means permissible in English and relates to the Islamic lifestyle and Muslim food consumption. The halal concept has transcended religious tenets and permeated various business domains, such as marketing (Wilson & Liu, 2010), finance (Hayat, den Butter, & Kock, 2013), banking (Butt & Aftab, 2013), travel (Battour & Ismail, 2016) and logistics (Talib & Hamid, 2014) in recent decades. This permeation reflects the potential and high industry demand for halal and Islamic economies.
Despite its vigorous growth and enormous potential, the halal food sector generates waste and pollution, jeopardising environmental sustainability. Nonetheless, there are limited data to corroborate this claim. Previous literature depicted that food surplus and wastage are growing problems that various industries face due to the widespread availability of food (Huang, Liu, & Hsu, 2020). Similarly, Sulaiman, Othman, Baharuddin, Mokhtar, and Tabatabaei (2014) postulated that the growing Muslim population increases the halal food demand, inducing food wastage further.
Various halal food sectors and supply chain management have overlooked environmental impacts and sustainable practices. For example, Baran (2021) indicated no halal-themed business sustainability studies between 2010 and 2018. Similarly, Secinaro and Calandra (2020) postulated that sustainability measures were neglected. Sustainability efforts and initiatives in the halal food sector must be investigated (Secinaro & Calandra, 2020). Opportunely, there has been recent literature on halal businesses and sustainability. Haleem, Khan, and Khan (2021), Khan, Haleem, and Khan (2022), and Rejeb, Rejeb, and Zailani (2021), for instance, established a correlation between the halal food supply chain and the development of environmentally friendly ecosystems.
Therefore, this paper aims to answer the call for more sustainability-driven halal food research through a sustainable supply chain management (SSCM) lens. Specifically, the piece takes on a viewpoint approach that conceptualises and suggests propositions that underline the possible SSCM initiatives that could be implemented on a firm level. Additionally, this treatise intends to respond to Talib's (2021) and Talib and Wahab's (2021) recommendations for more studies on less-researched halal markets, such as Brunei Darussalam (Brunei). Fundamentally, it attempts to provide a narrative outlook and call into question 'what are the possible SSCM initiatives that could be implemented among halal-certified food companies in the Sultanate?' This paper argues that dedicated attention to lesser or smaller halal markets would enrich the literature, possibly unearth unforeseen issues or address gaps in the study area. Ideally, this article aspires for more halal-certified food companies in Brunei to practice SSCM and perhaps inform concerned stakeholders on the possible strategic and sustainable supply chain approaches.
Following this Introduction section, the remaining part of this viewpoint proceeds as follows. The second section details the overview and issues surrounding the Brunei halal food sector. Subsequently, the third section specifies the sustainability movement and the need for sustainable halal food supply chains (SHFSC). Then, the fourth section deliberates on sustainable supply chain initiatives and underlines several propositions relevant to Brunei's halal food sector. Lastly, the fifth section concludes by summarising the deliberations, addressing several limitations and suggesting actions for future research.

Overview and issues in the Brunei halal food sector
Brunei is an Islamic Constitutional Sultanate state in Southeast Asia with around 432,000 people (Musa, 2019). Brunei is the second wealthiest nation in Southeast Asia after Singapore AGJSR (Hamdan & Hoon, 2019), with a gross domestic product (GDP) per capita of approximately BND 36,500 (Department of Economic Planning and Statistics, 2021). The primary revenue source is oil and natural gas production and exportmaking Brunei a rentier state. Conversely, this high petroleum dependency is vulnerable to volatile global crude oil market prices (M€ uller, 2016). Consequently, the Brunei government recognises the urgent need to decrease reliance on non-sustainable energy revenues and diversify its industries (Musa, 2019).
The Brunei government has identified the global halal industry as a lucrative sector to reinvigorate and sustain the economy. Hamdan and Hoon (2019) postulated that the Brunei halal food sector primarily stimulates economic growth and attracts foreign investors. Kon (2018) highlighted that the halal food market generated approximately BND 103 million in revenue despite being a small market. According to the 2019 to 2020 State of the Global Islamic Economy Report, Brunei is a prominent halal food, pharmaceuticals and cosmetics, and tourism producer (DinarStandard, 2019). Moreover, the Brunei halal standards, logo (see Figure 1) and food certification are widely recognised and trusted, serving as an economic development tool to establish their global halal market position (Miskam, Hamid, & Othman, 2018;Kifli, 2019).
There are several drawbacks faced in the effort to leverage the halal economy. Firstly, Brunei imports most halal food products from Malaysia, Singapore, Indonesia, Australia and the United Kingdom (Talib, 2021). The heavy reliance on importing halal food is attributed to geographical limitations, which are unsuitable for cattle farming (Khalid, Haji Masr, Muhammad, & Pang, 2018;Talib, 2021). Resultantly, importing halal food generates a substantial carbon footprint. Recent studies have elucidated that the food supply chain significantly influences carbon dioxide (CO 2 ) emissions and increases carbon footprint (Ferguson Aikins & Ramanathan, 2020;Ribal, Estruch, Clemente, Fenollosa, & Sanju an, 2019;Striebig, Smitts, & Morton, 2019;Yang and Meng, 2020). Therefore, a high long-term dependency on imported halal food products is unsustainable.
The Brunei halal food industry generates food and municipal waste (Malik, 2011;Shams, Juani, & Guo, 2014). The World Bank Solid Waste Management Report indicates that Brunei generates 216 tonnes of solid waste daily and is expected to increase to 307 tonnes by 2050 halal food supply chain (Kaza, Yao, Bhada-Tata, & van Woerden, 2018). Food wastage and unsustainable manufacturing practices are significant issues often overlooked and overshadowed by marketing publicities (Haleem et al., 2021). The carbon footprint and halal food wastage indicate that business organisations and the public sector ignore SSCM practices, such as recycling food packaging, appropriate food scrap disposal and green transportation.
Collectively, the country's effort to be economically and environmentally sustainable contradicts the high dependency on food importation and unsustainable food waste and practices. Therefore, to achieve economic prosperity, protection of the environment, a sustainable ecosystem, and remain a competitive halal food sector, supply chain members in Brunei should practice a more sustainable supply chain approach cohesively.

Sustainability and sustainable halal food supply chain
Sustainability is a viable international socioeconomic system that persists over time (Costanza & Patten, 1995). Costanza and Patten (1995) postulated that a balanced economy and environment are imperative for survival in the dynamic business landscape. Additionally, it is vital to cultivate equitable natural resources and effectively distribute them to the current and future generations.
The definition of sustainability has evolved (Glavi c and Lukman, 2007), and a universal definition proves to be a challenge (Salas-Zapata & Ortiz-Muñoz, 2019). Consequently, this paper utilises the UN definition of sustainability as "meeting the current needs without compromising the future generation's ability to meet their own needs" (www.un.org). The supply network stakeholders must balance viable distribution practices and environmental preservation (Feng, Lai, & Zhu, 2022;Tseng, Islam, Karia, Fauzi, & Afrin, 2019;Wu & Pagell, 2011). According to Wu and Pagell (2011), organisations should aim to strike a balance between supply chain operation and continuous improvement with sustainable social and environmental aspects. More recently, Feng et al. (2022) concluded that the pressure to harmonise supply chain operation, environmental preservation and demand from market and regulatory requirements further signify the need to compromise the operationenvironment faction.
Aside from the conventional sustainable outlook, literature has anchored sustainability with religious callings (Filho, Dahms, & Consorte-McCrea, 2018;Tomalin, Haustein, & Kidy, 2019). For instance, Islam advocates sustainable practices like other religions (Aboul-Enein, 2018; Muhamad, Syihab, & Achour, 2019). In the Quran, Allah commands devotees to protect the environment and prevent wastage. Halal food has been gradually recognised as an ethical consumption symbol due to increased food consumption awareness (Billah et al., 2020). Subsequently, the demand for additional SHFSC is rising. Haleem et al. (2021) postulated that SHFSC is an ethical, fair, humane and responsible farm-to-fork approach that ensures effective sharia-compliant halal food product distribution. Nonetheless, the SHFSC implementation can holistically influence the economy, society and the environment. Rezai, Mohamed, and Shamsudin (2015, p. 11) elucidated that sustainable practices, such as clean and hygienic processes, food safety, environmentally friendly and animal welfare, are associated with halal principles and production. Moreover, Khan et al. (2022) depicted that the halal food supply network is correlated with consumer confidence, trust and product retention. This paper also indicated that the demand for halal product safety, quality and integrity encouraged organisations to employ sustainable halal practices. Therefore, the SHFCS practices will benefit the industries and consumers.
Despite establishing initial halal and sustainable practices, additional efforts must be undertaken to promote sustainable halal practices. For instance, there is various SHFSC literature studies from large halal markets, such as Malaysia (Ali & Suleiman, 2016;Rezai et al., 2015) and India (Khan et al., 2022). Consequently, additional research must be applied to smaller halal markets such as Brunei to obtain comprehensive knowledge. The following section highlights the sustainable initiatives that could be implemented in halal-certified Brunei food companies.

Proposed sustainable supply chain initiatives
This section provides conceptual information on SSCM initiatives to ensure Brunei SHFSC. The four initiatives are (1) responsible sourcing, (2) environmental purchasing, (3) sustainable packaging and (4) green transportation. In addition, this section will recommend four propositions that could be critical in facilitating decision-making.

Responsible sourcing
In its basic definition, sourcing is finding and choosing strategic partners for a continuous and effective supply chain collaboration (Talluri & Narasimhan, 2004). According to Talluri and Narasimhan (2004), sourcing is vital in the supply chain for a seamless operation where businesses can access crucial materials and resources to ensure adequate and timely supplies and satisfy customer demand. Fundamentally, sourcing aims to optimise a firm's competitive advantage and that of its suppliers and partners and capitalise on the extended supply chain network (Kotabe & Murray, 2004).
Furthermore, as businesses and governments are geared toward more sustainable and environmentally cautious undertakings, the term 'responsible sourcing' has emerged (Chen, 2022;Guo, Lee, & Swinney, 2016;van den Brink, Kleijn, Tukker, & Huisman, 2019). Responsible sourcing is achieving social, environmental and economic outcomes from sustainable practices (Carter & Rogers, 2008). The three outcomes are based on Elkington's (1998) triple bottom line notion where sustainability efforts should be channelled toward symbiotic impact between people, planet and profit. According to Zorzini, Hendry, Huq, and Stevenson (2015), profit alone is inadequate for firms to remain competitive in the current demanding business landscape. Pursuing sustainable sourcing should have a synergy between firms' proactiveness, organisational culture and values, technological application and support from the government (Carter & Rogers, 2008;Glass, Achour, Parry, & Nicholson, 2012;Guo et al., 2016;Zorzini et al., 2015).
Aside from the actors in implementing and achieving responsible sourcing, the feasible approach should also be considered. Efforts such as local sourcing, collaborative sourcing through supplier relationship management, multi-sourcing from trustworthy suppliers and buy-back contracts are valuable approaches to sourcing responsibly (Ambekar, Kapoor, Prakash, & Patyal, 2019;Guo et al., 2016;Schneider & Wallenburg, 2012). Taken together, halal-certified food companies should reconsider sourcing from international suppliers and opt for local sources. This approach would then reduce CO 2 emissions from the heavy importation of food supplies into the country. Therefore, the paper offers this proposition: Proposition 1. For the halal food industry to be sustainable, firms must focus on implementing responsible sourcing approaches, as doing so could have societal, environmental and economic repercussions.

Environmental purchasing
Purchasing is synonymous with procurement and sourcing, and the interchangeable use is often contested (Miemczyk, Johnsen, & Macquet, 2012;Trent & Monczka, 2003). However, this study depicts purchasing as a separate function from sourcing, consistent with Trent and Monczka's (2003) view that purchasing and sourcing have distinctive focus. This is because purchasing is concerned with economic transactions between buyers and suppliers. In contrast, sourcing involves coordinating common commodities and materials across multiple locations and supply chains (Trent and Monczka, 2003). Therefore, this piece argues that purchasing is successive to sourcing functions where businesses first find halal-certified materials, and only then do purchasing and economic transactions occur. Purchasing is integral in supply network administration and impacts goods and services coordination and stakeholder collaboration (Carr & Smeltzer, 1999;Leenders, Nollet, & Ellram, 1994). Over the years, purchasing has become crucial for managing supply chains, specifically in sustainable strategic or environmental purchasing (Adobor & McMullen, 2014;Johnsen, Miemczyk, & Howard, 2017). This viewpoint adopts the definition by Carter and Carter (1998, p. 660) that depicted environmental purchasing as a "supply chain management involvement to facilitate recycling, reuse and resource reduction".
According to V€ or€ osmarty, Dobos, and T atrai (2011), organisations adopt environmental purchasing for three reasons: (1) to avoid unfavourable outcomes (negative publicity or legislative penalisation), (2) to comply with industry norms or competition and (3) to benefit from financial and non-financial sustainability implications. Consumer pressure can instigate organisations to employ a sustainable approach. Given the prevalent use of the Internet, consumers are now more aware, engaging and environmentally conscious when purchasing online due to the Internet (Gazzola, Colombo, Pezzetti, & Nicolescu, 2017). Furthermore, local governmental and international pressures compel businesses to practice sustainable purchasing. For example, firms in the United States of America (USA) and the United Kingdom (UK) employ sustainable purchasing and supply networks due to legislative demands (Giunipero, Hooker, & Denslow, 2012;Thomson & Jackson, 2007). Accordingly, the Brunei public, consumers and external stakeholders must demand that halal-certified food companies enforce stricter SHFSC policies, encourage SSCM and practice environmental purchasing.
Pullman & Wikoff (2017) elucidated that environmental purchasing practices through local sourcing could reduce food waste and protect the environment. Similarly, Arora, Arora, Sivakumar, and Burke (2020) demonstrated that environmental purchasing measures could reduce waste and pollution, such as purchasing recycled and lightweight packaging and supplier collaborative efforts. Various literature depicted that environmental purchasing practices significantly influence economic and social performance (Arora et al., 2020;Laosirihongthong, Adebanjo, & Choon Tan, 2013;Vijayvargy, Thakkar, & Agarwal, 2017;Younis, Sundarakani, & Vel, 2016;Zailani, Jeyaraman, Vengadasan, & Premkumar, 2012). For example, Zailani et al. (2012) postulated that sustainable initiatives contribute to positive financial revenues, improved stakeholder image and relationships and reduced operating costs. Therefore, Brunei halal-certified food companies should adopt environmental purchasing to protect the environment and enhance business performance. Thus, this paper develops the following proposition: Proposition 2. Applying environmental purchasing, if done effectively and efficiently, may result in legitimising business, projecting a positive image and improving performance, which then supports sustainable objectives.

Sustainable packaging
Packaging has a substantial significance within the logistics and supply network management sectors. The packaging interface in supply chains considerably impacts an organisation's logistics, marketing and environmental functions (Hellstr€ om & Saghir, 2007). Nevertheless, packaging contributes to waste and pollution (Pauer, Wohner, Heinrich, & Tacker, 2019). Despite the negative stakeholder connotation and pressure, supply chain industries have started producing sustainable packaging to protect the environment (Pauer et al., 2019;Verghese & Lewis, 2007). Conversely, businesses have utilised measures, such as redesigning packaging design and functionality (Garc ıa-Arca & Prado, 2008), using innovative, sustainable packaging (Chen, Brahma, Mackay, Cao, & Aliakbarian, 2020) and environmentally friendly or bio-renewable packaging (Chaichana, 2020). These measures can reduce food waste (Brennan et al., 2021;Siracusa & Rosa, 2018). Sustainable packaging initiatives require various supply chain stakeholder support to be positively viable. For instance, government policies and regulations drive sustainable packaging among businesses and consumers (Meherishi, Narayana, & Ranjani, 2019). Furthermore, top management support is imperative to encourage and sustain sustainable packaging usage and practices on a firm level (Gardas, Raut, & Narkhede, 2019). Zailani et al. (2012) postulated that sustainable packaging significantly influences economic and social performance, encouraging more organisations to practice SSCM. Moreover, through pre-emptive and integrated sustainable packaging operations, organisations can increase operational performance and competitiveness (Afif, Rebolledo, & Roy, 2022; Garc ıa-Arca, Gonz alez-Portela Garrido, & Prado-Prado, 2017). Therefore, governmental support and top management encouragement are vital for organisations to adopt sustainable packaging, leading to sustainable performance. Meherishi et al. (2019) elucidated that additional efforts must be undertaken toward sustainable packaging implementation in developing countries as the current literature is predominantly concentrated in Western developed countries. This study postulated that sustainable packaging research should expand into different economies and industries to encourage additional implementation and accelerate circular economy efforts. Therefore, sustainable packaging should be a viable solution for Brunei's upstream and downstream SHFSC. Based on the above deliberation, the paper proposes: Proposition 3. When halal-certified food companies utilise sustainable packaging in the supply chain, it could help to reduce environmental degradation and potentially influence economic, social and environmental performance.

Green transportation
Transportation is the driving force in supply chain management and aids in goods and people's movement from one location to another (Speranza, 2018). Bj€ orklund (2011, p. 12) utilises the term 'green transportation' or a 'transportation service that reduces negative implications on human and environmental health compared to competing transportation services. This study highlighted the role of sustainable transportation that encompasses regular vehicle functions and reduces adverse environmental impacts. Larger, sophisticated and convenient transportation benefits the supply chain but contributes to environmental degradation (Raza, Shah, & Sharif, 2019;Speranza, 2018;Tiwari, Khalfaoui, Saidi, & Shahbaz, 2020). Nevertheless, transportation is becoming a part of sustainable environmental initiatives, and governmental, business and consumer efforts have simultaneously altered the outlook where sustainable supply chains and transportation advancement.
Over the years, transport manufacturers, operators and consumers have enjoyed diverse sustainable and green transport, such as electric vehicles (Speranza, 2018). For example, Colicchia, Marchet, Melacini, and Perotti (2013) and Sureeyatanapas, Poophiukhok, and Pathumnakul (2018) highlighted that the logistics service providers support green transportation initiatives. Additionally, Colicchia et al. (2013) also depicted that electric or hybrid vehicle usage, alternative fuels, effective routing systems, more efficient shipment consolidation and full-truck-load operations were transport-based environmental efforts that could benefit the environment and reduce CO 2 emissions.
There are numerous motivations to utilise green transportation. Ellram and Murfield (2017) elucidated that green transportation is cost-saving, lower regulation risk, decreases fuel or energy usage and reduces the environmental burden. Moreover, sustainable transport businesses possess improved service performance, positive reputations, improved opportunities and collaborations (Ellram & Murfield, 2017). Therefore, organisations that adopt green transportation can increase environmental, economic and operational performance (Centobelli, Cerchione, & Esposito, 2017).
Collaborative efforts are vital for green transportation initiatives implementation. Speranza (2018) depicted that additional collaborative efforts from the government, private sectors and consumers are imperative. For example, consumers could contribute through collaborative consumption, such as on-demand mobility and crowdsourcing (Speranza, 2018). Additionally, governmental efforts could drive green transportation initiatives through regulations, policies, subventions and tax instruments (Bj€ orklund, 2011). Nonetheless, Bj€ orklund (2011) emphasise that the government should participate cautiously as businesses may perceive it as impeding rather than facilitating sustainable environmental development. The Brunei National Climate Change Policy's Electric Vehicle Pilot Project indicated the government's role in attaining the "Wawasan Brunei 2035" vision. Thus, it indicates that the Brunei government drives other halal food businesses to adopt green transportation and SHFSC practices. The paper suggests this proposition: Proposition 4. Utilising green transportation centred on sustainable operation, with collaborative efforts and implementation among upstream and downstream supply chain players, would contribute to a sustainable future and improve economic and operational performance.
The four environmentally cautious approaches of responsible sourcing, environmental purchasing, sustainable packaging and green transportation are viable actions that could help instigate supply chain members to practice SSCM. However, the list is not limited to the four SSCM practices mentioned above. Other initiatives such as technology adoption, sustainable supplier selection and implementation of traceability systems are equally significant undertakings. Nevertheless, the authors emphasised the four SSCM and propositions deliberated above on the basis that businesses can establish the practices internally within an organisation with little influence, dependency or pressure from external parties such as the government, suppliers or competitors.

Conclusions, limitations and future research
Sustainability and halal business-themed literature are dispersed and have gained substantial attention from the industry and academia. As these domains expand, the halal and sustainability interlink is inevitable. This paper considered the potential SSCM practices toward Brunei halal food supply chain and aims to contribute to the "Wawasan Brunei 2035" vision. This piece is considered among the first and the few that highlight four potential SSCM practices and propositions that can be implemented from a Brunei standpoint: responsible sourcing, environmental purchasing, sustainable packaging and green transportation. By implementing the four proposed SSCM approaches, the upstream and downstream halal food supply chains coming into the country are not only shariahcompliant and tayyib but are sustainable in terms of business longevity and environmentalfriendly.
There are two feasible courses of action for SSCM that may provide fruitful avenues to encourage SHFSC in Brunei. Firstly, a detailed SSCM literature review must be executed to comprehensively understand the sustainable initiative's urgency. This paper will significantly impact future business undertakings, particularly Brunei sustainability endeavours, highlighting other potential SSCM practices beyond the proposed initiatives.
Secondly, a natural progression of this viewpoint is to consider the relevant theoretical framework that could provide a more nuanced understanding and deduced deliberation. For instance, researchers in the future could consider established frameworks like the structureconduct-performance, the triple bottom line approach or the transaction cost theory. These frameworks and many more in the literature may contribute to understanding the need for SSCM practices in the halal supply chains and its impact on the Brunei economy.
Thirdly, future studies should investigate the SSCM impacts on business performance. Previous literature depicted the correlation between sustainable efforts and improved environmental, social, economic and operational performances, which benefits Brunei supply chain entities such as halal food companies. Therefore, additional insight will reinforce the sustainability-performance association, encourage other SSCM practices and enrich the HFSCM literature.
There were several limitations in this study. This viewpoint is a preliminary qualitative study focusing on limited literature that may overlook several vital studies. Additionally, the views are confined to the four SSCM practices within Brunei context and that they cannot be generalised. Besides, other SSCM practices, for instance, technology adoption, sustainable supplier selection and implementation of traceability systems, are precluded from this treatise. Future research may consider the inclusion that would enrich and entice more SSCM practices among halal-certified food companies in Brunei. Nevertheless, this price is timely, setting a foundation for future comprehensive studies that can contribute to further sustainable initiative pursuit.