Loong-Tak Lim

University of Guelph | UOGuelph · Department of Food Science

Carbon dots (CDs) are becoming increasingly popular in various sectors due to their non-toxic, biocompatible properties and adjustable photoluminescence. There is a growing interest in utilizing CDs to create advanced sensing systems, especially in the food industry. By embedding a CD-based detection platform within food packaging, it is feasible t...

We examined the effects of riverbed roughness and turbulence (shear velocity, u*$$ {u}_{\ast } $$) on propagule dispersion in the near‐field region (< 100 m) by releasing microbead models of larval and juvenile unionid mussels in tributaries of the Grand River (Ontario, Canada). The Conestogo River had the roughest bed and highest mean u*$$ {u}_{\a...

With the issue of plastic waste persisting and the need for more sustainable solutions to the ever‐increasing demand for lightweight and durable plastic products, this review has become imminent and compelling. Poly (butylene adipate‐co‐terephthalate) (PBAT) is a biodegradable polymer with exceptional film‐forming ability resembling those of low‐de...

Electrospun nonwovens of biopolymers are gaining popularity in filtration, coatings, encapsulation, and packaging materials. However, their applications are hindered by limited stability, particularly when loaded with lipids. This research aimed to apply a multiscale approach to gain insights into deteriorative processes, e.g., oxidation, limiting...

The toxicity and environmental concerns of methyl bromide (MB) have been a significant impetus for research into environmentally benign fumigant alternatives. Ethyl formate (EF) and chlorine dioxide (ClO 2 ) are FDA‐approved agents with potential as alternatives to MB. However, both are chemically unstable and pose considerable end‐use challenges....

In this research, dual-activated wheat gluten-based nanocomposite active films reinforced by chitosan nanofibers (CHNF) was developed, as well as co-loaded with betanin (BET) and carvone (CAR) for application in food packaging. Free and cationic inulin-coated nanoliposomal forms of BET/CAR were incorporated into the gluten films at 0, 5, and 10% (w...

This study investigated a continuous circulation cold brewing (CCCB) process using a modified single‐serve brewer that allowed recirculation of the brew within the single‐use capsules. The changes of total dissolved solids (TDS), titratable acidity (TA), caffeine and 5‐caffeoylquinic (5‐CQA) concentrations over time during the CCCB process were eva...

This study utilized post-industrial wheat starch (biological macromolecule) for the development of poly(butylene adipate-co-terephthalate) (PBAT) based thermoplastic starch blend (TPS) and biocomposite films. PBAT (70 wt%) was blended with plasticized post-industrial wheat starch (PPWS) (30 wt%) and reinforced with talc master batch (MB) (25 wt%) u...

Casein proteins were cross-linked with dialdehyde tragacanth gum (DTG) to create a film with improved physico-mechanical properties. The DTG/casein film with a 2:1 ratio exhibited good physical and barrier properties, such as tensile strength (TS) (12.92 MPa), water contact angle (WCA) (73.2°), water vapor permeability (WVP) (2.1 × 10 − 10 g·mm/h·m...

Avocados’ shelf life is limited and difficult to monitor. This study evaluated the performance of chitosan coatings (1.5 and 2 % w/v, T1 & T2) on avocados' quality and shelf-life against samples untreated (C) and treated with an ethylene inhibitor (1-MCP, M). Hyperspectral imaging (HSI) coupled with machine learning (ML) techniques were also evalua...

This chapter begins with the many pieces of evidence collected over the years that demonstrate the health benefits of omega-3 fatty acids docosahexaenoic acid, eicosapentaenoic acid, saturated medium-chain fatty acid, and other nutritional fatty acids in various medical conditions including cardiovascular disease protective effects. Recent advancem...

The effects of aqueous and deuterium oxide (D2O) solutions of alcohols (methanol, ethanol, 1‐propanol, 2‐propanol, and 1‐butanol) on the thermomechanical properties of poly(lactic acid)—PLA—films were assessed by dynamic mechanical analysis. The glass transition temperature (Tg) of PLA films immersed in 25%, 50%, 75%, and 100% (v/v) alcoholic solut...

Biobased packaging materials derived from carbon-neutral feedstocks are sustainable alternatives to conventional fossil-based polymers. In this study, a method was developed to prepare paper-sheets derived from Miscanthus × giganteus cellulose fibers for potential food contact applications. The papers were hydrophobized with modified lignin extract...

Multifunctional active and innovative biopolymer-based indicator films consisting of a blend of gelatin (GEL) and basil seed gum (BSG) with different concentrations of saffron petal extract (SPE) were prepared. The a* and b* color values depended on pH, which highlighted that the SPE could be used as a pH indicator. The results showed the anthocyan...

The use of poly(lactic acid) (PLA) in packaging and other consumer products has increased considerably over the past decade. This chapter provides an overview of the main process technologies for PLA and presents the material properties needed for selected processing technologies. Additives are formulated into PLA during processing to enhance its m...

In this study, starch/PBAT antimicrobial films with different ε-polylysine hydrochloride (ε-PL) contents (0, 1, 2, 3, and 4 wt%) were developed by extrusion blowing. Rheological results indicated that incorporation of ε-PL decreased the complex viscosity and storage modulus of blends. Fourier transform infrared spectra revealed that intermolecular...

The transport of particulate matter including the gametes, larvae and propagules of reproducing organisms and other organic matter involved in nutrient/contaminant transport are important processes, yet there are few environmentally friendly methods available to examine dispersal empirically. Herein we report on the development and application of a...

Bioactive compounds (e.g., nutraceuticals, micronutrients, antimicrobial, antioxidant) are added to food products and formulations to enhance sensorial/nutritional attributes and/or shelf-life. Many of these bioactives are susceptible to degradation when exposed to environmental and processing factors. Others involve in undesirable interactions wit...

BACKGROUND In this study, the foamability and foam stability of nitrogen‐infused cold brew coffee, as affected by coffee variety (Arabica and Robusta), degree of roast (light, medium, dark), brewing temperature (4, 20, 35 °C), brew ratio (1:5–1:15 w/w; coffee/water), ground particle size (712, 647 and 437 μm volume mean diameter) and beverage tempe...

Intelligent food packaging system exhibits enhanced communication function by providing dynamic product information to various stakeholders (e.g., consumers, retailers, distributors) in the supply chain. One example of intelligent packaging involves the use of colorimetric indicators, which when subjected to external stimuli (e.g., moisture, gas/va...

Films are standalone structures with mechanical properties optimal for further downstream handling and processing. By contrast, coatings are thin continuous layers formed on a substrate surface. Proteins from dried seeds of legume are highly functional; through physical and/or chemical treatments, these biopolymers can be converted readily into coh...

Miscanthus, a high yield and low maintenance perennial plant with a high cellulose fiber contents, is a potential feedstock for pulp production. In this study, a binary enzyme cocktail of cellulase and laccase was employed for the extraction of cellulose microfibers from miscanthus biomass. The effect of enzyme concentrations (0.10%, 0.15%, 0.20%,...

Plant-based meat analogues are products that mimic the appearance, flavour, mouthfeel, fibrous texture, and chemical characteristics of meat products but made from plant origins. The production of plant-based meat analogues uses less resources (e.g., electricity, water, and land) and generates less pollution (e.g., greenhouse gas emission) than mea...

The aim of the present study was to investigate the cationization of inulin with Williamson’s etherification method, and compare cationic inulin with unmodified inulin coatings for stabilizing nanoliposomes (NLPs). The synthetized cationic inulin was characterized by Fourier transforms infrared (FT-IR) spectroscopy, carbon hydrogen nitrogen (CHN) e...

Many food products are sensitive to oxygen which can promote rancidity, aerobic microorganism growth, browning, vitamin degradation, flavor loss, and other undesirable reactions. Active packaging concepts have been successfully applied to delay these deteriorative phenomena. In particular, oxygen scavengers help limit O2 ingress into packaging thus...

In this study, we report a top-down approach to fabricate starch nanoplatelets (SNPs) based on a deep eutectic solvent (DES) comprised of choline chloride and oxalic acid dihydrate. When subjecting waxy maize starch (WMS) to 2 h of DES treatment, the SNPs of oxalate half-ester were successfully fabricated. The formation mechanism of SNPs was studie...

Over the past decade, cold brew coffee has gained increasing popularity due to its perceived smoother, sweeter, and less acidic sensory profile than the hot brew counterpart. However, the preparation of cold brew coffee is time-consuming, ranging from 6 to 24 h of extraction at refrigerated to room temperature. To address this challenge, the presen...

The transport of particulate matter including the gametes, larvae and propagules of reproducing organisms and other organic matter involved in nutrient/contaminant transport are important processes, yet there are few environmentally friendly methods available to examine dispersal empirically. Herein we report on the development and application of a...

Gaseous and volatile active compounds are versatile to enhance safety and preserve quality of agri‐food products during storage and distribution. However, the use of these compounds is limited by their high vapor pressure and/or chemical instability, especially in active packaging (AP) applications. Various approaches for stabilizing and controllin...

Ethyl formate (EF) is a food-flavoring agent with a generally regarded as safe (GRAS) status. It is a naturally-occurring insecticidal volatile compound promising as an alternative to synthetic insect pest fumigants that are toxic and/or undesirable to the environment. In this study, an EF precursor (EFP) was investigated as an activated EF release...

Edible antimicrobial films made from starch/gelatin (S/G) incorporated with different ε-polylysine hydrochloride (ε-PL) contents were developed by low-temperature extrusion blowing process. ε-PL addition reduced the complex viscosity and storage modulus of blends, while promoted the formation of hydrogen bonding among film components. The control f...

In this current work, antimicrobial films based on starch, poly(butylene adipate-co-terephthalate) (PBAT), and a commercially available AgNPs@SiO2 antibacterial composite particle product were produced by using a melt blending and blowing technique. The effects of AgNPs@SiO2 at various loadings (0, 1, 2, 3, and 4 wt%) on the physicochemical propert...

Betanin (BET) and carvone (CAR) as antioxidant and antibacterial compounds were co-loaded in the coated nanoliposomes (NLPs) with cationic inulin to improve their stability and bioavailability. A cationic inulin was successfully synthesized and used for surface coating of the NLPs. The zeta potential, particle size, and PDI values of the coated NLP...

Gradient colorimetric indicators were developed by piezoelectric inkjet-printing, for monitoring the freshness of packaged fish fillets stored at 4 °C for 7 days. The pH-sensitive indicators involving three sulfonephthalein dyes were printed on inkjet photographic papers and applied as “intelligent” labels that were exposed to the headspace of the...

Phenolic compounds are prone to degradation from external deleterious conditions. Thus, a carrier for its delivery can be useful in protecting them and ensuring their optimal release profile. The objective of this study was to produce starch nanofibers as delivery carriers for carvacrol and to evaluate its in-vitro digestion simulation and anti-gli...

Heat sealing is one of the most common techniques for sealing food packages. In this study, the effects of sealer parameters such as dwell time (0.5–2 s), jaw temperature (225–250°C) and pressure (69–345 KPa) and the seal contaminants (coffee particles [0.70–0.85 mm]) were studied on polymer materials used in coffee capsules: (1) lidding, poly(ethy...

Fresh meat products are highly perishable and require optimal packaging conditions to maintain and potentially extend shelf-life. Recently, researchers have developed functional, active packaging systems that are capable of interacting with food products, package headspace, and/or the environment to enhance product shelf-life. Among these systems,...

In this study, the extraction kinetics, based on total dissolved solid (TDS), at different temperatures (4, 23, 50, and 93°C) for different grind sizes (VMD = 139, 643, 1,450, 1,747 μm) were investigated. Coffee extraction proceeded in initial fast extraction stage followed by a significantly slower extraction stage, which correspond to the extract...

Starch nanocrystals (SNCs) are insoluble platelet particles with multifunctional properties. Production of SNCs is mainly based on acid hydrolysis of corn starch with low yield. This study focused on investigating the effect of pretreatments (heat-moisturetreatment (HMT), annealing (ANN) and sonication (SNT)) on unconventional pinhão starch to prod...

Hexanal slows down the ripening process in fresh produce by inhibiting the activity of phospholipase D, thereby increasing their shelf life. This study focused on comparing the single time exposure and continuous exposure of post-harvest of ‘Anjou’ and ‘Bartlett’ pears to hexanal by dipping or fumigating to enhance their shelf life. Continuous expo...

Direct application of active and volatile compounds of essential oils (EOs) is ineffective in food and uncontrolled release of these compounds may be undesirable from sensory and antimicrobial efficacy standpoints. The present study aimed to develop and characterize the physical and antimicrobial properties of casting composite chitosan (CS) thin f...

Piperine (PIP) is an alkaloid which is potent as a therapeutic agent. However, its applications are restricted by its poor water solubility. Nanosponges (NS) derived from polymers are versatile carriers for poor water-soluble substances. The aim of this work was to synthesize β-cyclodextrin NS, by microwave-assisted fusion, for the encapsulation of...

Hexanal and salicylaldehyde are naturally-occurring antimicrobial volatiles from edible plants known for their efficacy for post-harvest preservation of fruits and vegetables. Due to their volatility and susceptibility to oxidation, these volatiles must be encapsulated within a carrier to control their release, especially when applied in modified a...

Zein-based materials were produced by dissolving zein water at pH 13, and subsequently congealing it with CaCl2. Biocarbon particles were produced with miscanthus biomass by pyrolization at 650 °C (M-L) and at 900 °C (M-H), followed by ball-milling. Increasing the pyrolization temperature caused the disappearance of functional groups on the particl...

Zein-based materials were used to remove Trypan blue from water under flow conditions and in batch tests. In flow tests, zein dissolved at pH = 13 was injected in sand columns and subsequently coagulated with CaCl 2 , to create an adsorbent filter which removed over 99% of Trypan blue. Batch tests were conducted using zein powder, zein dissolved at...

Over the past decade, electrospun and electrosprayed materials are increasingly being exploited for food applications to address shelf life and stability issues. Food-grade biopolymers and synthetic polymers have been electrospun into nonwoven or electrosprayed into particulate carriers to encapsulate various bioactives for different purposes such...

The aim of this study was to encapsulate orange essential oil (OEO) in zein polymer by the electrospinning/electrospraying techniques. OEO at concentrations of 30, 40 and 50% (w/w), was incorporated into 10 and 20% (w/v) zein polymer solutions, for the formation of the capsules and fibers, respectively. The polymer solutions were evaluated for zeta...

The present disclosure relates to compounds of the formula (I) which are precursor compounds of esters, whereby upon hydrolysis of the precursor compound, an ester compound is released. This ester precursor approach can be useful for applications where controlled release of, for example, ethyl formate, is beneficial.

Phospholipase D (PLD) is a key enzyme involved in membrane lipid catabolism. Hexanal, a C6 volatile aldehyde is a strong PLD -inhibitor, and has been observed to enhance the shelf life and quality of horticultural produce. In the present study, the effect of hexanal vapor exposure on the postharvest quality and ripening response of bell pepper frui...

Oxidizing emulsifiers were produced using calcium peroxide and polysaccharides extracted from edible mushrooms. The polysacchardes were mainly glucans, as indicated by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy. Our study investigates the potential application of these oxidizing emulsifiers to remediate and immo...

Selection and characterization of biomass feedstocks with the maximum biomaterial or biofuel yields need the accessibility of reliable and efficient methods for structural and compositional characterization of plant material. Understanding microstructure of lignocellulosic fibre is required to evaluate the heat and mass transfer phenomena, bond for...

Ethyl formate (EF) is a naturally occurring insecticidal and antimicrobial volatile compound promising as an alternative to synthetic fumigants. In this work, an EF precursor (EFP) was encapsulated in free-surface electrospun ethylcellulose/poly (ethylene oxide) (EC-PEO) nonwovens and the release of EF from the precursor was evaluated using gas chr...

Hexanal extends the shelf life of fresh produce. Due to its high volatility and spontaneous oxidation, control release of hexanal is a challenge. The objective of the study was to stabilize and encapsulate hexanal as an acid labile precursor in polymeric nonwovens and trigger its release in moisture environments in packaged fresh produce. Bilayer n...

Zein and laccase were used to remove naphthalene from water using two approaches. The first approach sorbed naphthalene onto laccase-containing solid zein sorbents coagulated with either CaCl2 at pH = 13 or with Fe2Cl3 at pH = 10. These sorbents were never used before for this purpose. Fluorescence spectroscopy showed that laccase degraded naphthal...

The existing fumigants for quarantine purposes are toxic and/or undesirable to the environment such as methyl bromide which is being phased out by governmental agencies. Ethyl formate (EF) is a naturally-occurring volatile compound with GRAS status. It is a potent insecticide and antimicrobial agent, promising as an alternative to synthetic counter...

Pseudomonas sp. bacteria were incorporated into a double emulsion system (water in oil in water, W/O/W), which can be injected in the subsurface to trap and biotreat naphthalene. The outermost phase of the W/O/W emulsion was an aqueous solution of chitosan (1.65 wt.%). Naphthalene could be dispersed in the aqueous chitosan phase of W/O/W emulsions....

The existing fumigants for quarantine purposes are toxic and/or undesirable to the environment. Hence, there is an urgent need to develop alternative fumigation technologies. Ethyl formate (EF) is a naturally-occurring volatile compound with GRAS status. However, its high volatility and flammability pose substantial end-use delivery challenges. In...

The existing fumigants for quarantine purposes are toxic and/or undesirable to the environment. Hence, there is an urgent need to develop alternative fumigation technologies. Ethyl formate (EF) is a naturally-occurring volatile compound with GRAS status. Research has shown that it is a potent insecticide and antimicrobial agent, promising as an alt...

Ultrasound-assisted-alkali-urea (UAAU) pre-treatment of miscanthus biomass was investigated for enhanced delignification and extraction of cellulose fiber. The effect of pre-treatment conditions, sonication time (10.0, 15.0 and 20.0 min), alkali (NaOH) concentration (2.0, 3.5 and 5.0%, w/v) and urea-concentration (1.0, 1.75 and 2.5%, w/v) on the de...

The study examined the efficacy of using bacteriophage as an additive in a cooked-meat model system to control growth of contaminating Listeria monocytogenes during subsequent storage. Studies were designed where Listeria bacteriophage A511 and L. monocytogenes introduced inside or on the surface of the cooked-meat to simulate different bacteriopha...

One of the important commercial usages of pectinase is the depectinization and clarification of fruit juices. The application of native enzymes for industrial utilization has limitations such as high production cost, instability with operational conditions, difficulty in separation of products from reaction media, and lack of reusability. In this s...

The objective of this research was to incorporate an ingredient obtained from spent cellulose casings in beef emulsion modeling systems. The test ingredient (residual sausage casing, RSC) was procured from cellulose sausage casings following thermal processing of the sausages. The casings were cleaned of contaminants before a combination of enzymat...