• Many dangerous pathogens cannot be identified visually, making tools like biosensors essential for early intervention.

• Biosensors fill gaps left by audits, certifications and slow laboratory tests, especially for SMEs.

• As affordable, portable technologies, biosensors can protect consumers and uphold the integrity of halal and food safety across the supply chain.

HE agrofood industry is under increasing pressure to keep pace with growing demand, complex supply chains, and rising consumer expectations for freshness, quality and safety.

Yet many threats to food safety, especially microbial and chemical contamination, are invisible, fast-moving, and difficult to detect with traditional methods.

Whether in livestock, aquaculture, crop production or ready-to-eat( RTE) processing, a single lapse in hygiene or handling can allow harmful microorganisms such as Salmonella, Listeria, and Vibrio to enter the food chain. These pathogens cannot be seen, smelt or detected by visual inspection alone, yet they remain among the leading causes of foodborne illness globally.

As agrofood operations expand, the industry faces a critical question:“ How do we detect contamination earlier, faster and( much better) at the source, before products reach consumers?”

This is where biosensors are emerging as one of the most promising innovations for modern food safety. Compact, rapid, and field-ready, they offer real-time monitoring that traditional laboratory methods cannot match.

INVISIBLE RISKS

Many food products may appear perfectly fine on the surface but may still harbour harmful microbes. Visual inspection alone is unreliable because microorganisms such as bacteria, viruses, and fungi are invisible to the naked eye. Today’ s agrofood supply chains are longer, more complex and increasingly global.

Products move through multiple handling stages, from farms to processing plants, distributors and retailers, where each step introduces opportunities for contamination. According to FAO and WHO( 2021), many foodborne pathogens are undetectable

By Noor Athirah Yusri and Nurhidayu Al-saari

International Institute for Halal Research and Training( INHART), IIUM through visual inspection alone yet can survive or multiply at various points along the supply chain.

Contamination can occur when farm operations lack proper hygiene, when water quality is poor, or when temperature control in cold-chain logistics is compromised. These conditions allow a range of hazards, such as microbial, chemical, or toxinrelated, to infiltrate food products. These could put public health and established food safety assurance integrity at risk.

This issue is particularly relevant for food producers, especially those involved in ready-to-eat( RTE) meals, dairy, and seafood production, as these products are among the highest-risk for Listeria contamination( Leclercq et al., 2021), are highly perishable, and are sensitive to temperature and hygiene controls.

FOOD SAFETY ASSURANCE

Food certification and regulatory compliance have long served as trusted benchmarks for consumers, assuring that products are produced responsibly and in accordance with required hygiene and safety standards.

Beyond logos and documentation, modern food assurance emphasises not only regulatory compliance but also robust systems that ensure wholesomeness, hygiene and safety throughout the production chain.

In Malaysia, frameworks such as HACCP, GMP, and ISO 22000 provide robust guidance to strengthen food hygiene and safety practices. Halal certification inherently incorporates the principles of Toyyib, ensuring that food is not only permissible but also clean, safe, and wholesome.

At the same time, MeSTI helps small producers meet baseline safety standards, supporting compliance across the entire food production chain( Jais, 2019)

While certification confirms adherence to established requirements and basic safety standards, it may not always capture realtime or invisible microbial threats during handling and processing.

A recent enforcement case in Cheras exposed serious halal and hygiene breaches at illegal poultry slaughterhouses, where bloodstained areas, poor sanitation and improper waste disposal were found( Mahari, 2025). Now imagine products from such facilities entering the market under false or unverified claims of safety.

Consumers, trusting the logo and system, might unknowingly purchase them, potentially leading to severe foodborne illnesses such as Salmonella infection leading to death( Malay Mail, 2013). The public outcry, regulatory scrutiny and damage to institutional trust would be immense. Without proper oversight, small producers risk reputational and financial losses due to food safety failures.

Given these vulnerabilities, relying solely on visual inspection and documentation during audits may leave blind spots in food safety oversight. This gap does not reflect a failure of the assurance system but rather highlights a growing need to complement audits with scientific tools.

TRADITIONAL TESTING

Laboratory-based testing, such as regrowing the bacteria on culture media or polymerase chain reaction( PCR), which makes millions of copies of DNA fragments unique to a single microorganism, remains the gold standard for detecting the harmful one.

However, these methods are often slow, expensive and require multiple complex steps, including sample collection, transport, culturing and biochemical or molecular testing. The whole process can even take from 24 hours to several days( Campbell et al., 2021).

In fast-moving food systems, such delays can hinder timely intervention, especially for fresh produce, where spoilage occurs rapidly, and in livestock or aquaculture operations, where