16IHC - posters

Id	Title	Abstract
Po1-	Enhancement of the intestine permeability of curcumin using Pickering emulsions stabilized by starch crystals and chitosan	abstract
Po2-	Impact of free fatty acids on the foaming capacity of 2% commercial milk: experiments and theory	abstract
Po3-	Influence of rheological properties on gastrointestinal digestion and curcumin release of emulsion-filled starch gels	abstract
Po4-	Valorization of canned liquids from Ontario native pulses as egg alternatives	abstract
Po5-	Impact of free calcium and magnesium incorporation to the heat-stability of a model UHT milk with dairy and soy protein	abstract
Po6-	Impact of high concentration dietary fiber substitution on rheological, structural, microstructural, and thermal properties of wheat flour dough	abstract
Po7-	Moringa peregrina press cake as a novel source of dietary protein and fiber; the effect on in vitro starch digestibility and antioxidant activity of bread	abstract
Po8-	Effects Of Camel Age and Plasticizes On the Properties Of Camel Bone Gelatin Films	abstract
Po9-	Exploring commercial utilization of yellow mustard (sinapis alba l.) gum: stabilization and emulsification in vegetarian mayonnaise and non-dairy fat whipping cream	abstract
Po10-	Ethyl cellulose-zein based latex films	abstract
Po11-	Imaging techniques to characterize pulse-based extruded food products: A review	abstract

Enhancement of the intestine permeability of curcumin using Pickering emulsions stabilized by starch crystals and chitosan

Myeongsu Jo¹, Young Jin Choi²

¹Department of Grain Science and Industry, Kansas State University, Manhattan, KS 66506, US
²Center for Food and Bioconvergence, Seoul National University, Gwanakgu, Seoul 08826, Republic of Korea

Introduction: The intestine permeability of curcumin was improved by using Pickering emulsion stabilized with starch crystals and chitosan

Method: We designed curcumin-loaded chitosan-coated Pickering emulsions and examined digestibility, bioaccessibility, mucoadhesiveness, and intestinal absorption of curcumin using in vitro models of the human GI tract. In digestion studies, changes in D3,2, ζ-potential (ZP), and the lipolysis patterns of the emulsions were monitored after treatment with simulated digestion fluids, and the amount of curcumin solubilized in the mixed micellar fraction was determined. The permeation rate of curcumin across an intestinal monolayer membrane was assessed using the Caco-2 cell-membrane model covered with biosimilar mucus.

Results: The chitosan-coated emulsions, differed from uncoated emulsions, underwent the gastric condition with no size change and exhibited relatively slow lipolysis pattern in the small intestinal condition. Additionally, > 70% of curcumin was soluble in the micellar fraction after all the digestion, irrespective of the chitosan coating. Curcumin loaded in > 0.1% chitosan-coated emulsions adhered more robustly onto porcine intestinal mucosa than did curcumin powder and chitosan-uncoated emulsions. Curcumin incorporated in the chitosan-coated emulsions showed relatively rapid and large permeation pattern, ~9.5-times apparent permeability compared to curcumin solution.

Discussion: Based on the results obtained using microscopic images of porcine intestinal mucosa and mucus-covered Caco-2 membrane, the increased permeability of curcumin is due to the electrostatic mucoadhesion and epithelial tight junction opening effects by the chitosan-coating. Our findings will facilitate the rational design for oral delivery systems incorporating food-grade lipophilic bioactives such as curcumin.

Impact of free fatty acids on the foaming capacity of 2% commercial milk: experiments and theory

Siyu Liu¹, David Pink^1,2 , Gisele LaPointe¹, Fernanda Peyronel¹

¹Food Science Department, University of Guelph, Guelph, ON, Canada
²Physics Department, St.Francis Xavier University, Antigonish, NS, Canada

Cappuccino-style drinks appeal to many consumers thanks to the microfoam created by the barista at the time of serving. However, the ability to create microfoams is sometimes compromised by the quality of the milk. One of the proposed reasons for poor foam formation is the presence of free fatty acids (FFA). This work studies foamability and foam stability (Kamath et al., 2008) of two types of commercial milk that were enzymatically treated to create FFA. Both types of milk contained 2% fat: one came from cows fed with traditional grass, while the second came from cows fed with organic grass. FFA was measured using two methods: [i] manual titration after a solvent extraction and, [ii] Fourier transform mid-infrared spectrometry (FT-MIR). The FT-MIR measurements were carried out by the Canadian accredited dairy testing lab (Agriculture & Food Laboratory, University of Guelph).

The average FFA value obtained by manual titration was 4.4 ± 1.3 μ equiv/mL for organic grass-fed cows and 6.7 ± 2.5 μ equiv/mL for traditionally grass-fed cows, while the FT-MIR method gave values of 0.2 ± 0.2 mmol/100 g fat and 0 mmol/100 g fat respectively. The manual titration as well as the FT-MIR reported similar trends regarding the FFA amount in all samples, although the FTI-MIR does not seem to be too sensitive for those samples with low amounts of FFA. The foamability of the control milk samples were 80 mL. Similar values were obtained for those milks to which 0.0005 and 0.001 mg/ml of enzyme was added. However, the foamability was ~70% lower when 0.0025 and 0.01 mg/mL enzyme were added. When more than 0.0005 mg/mL (0.001, 0.0025, 0.01, and 0.1 mg/mL) of enzyme was added to the milk, which corresponds to 8 μ equiv/mL < FFA < 42 μ equiv/mL, the foam formed was different from the milks with the rest of enzyme-treated milk samples. Instead of forming a microfoam, those samples showed large bubbles that were distributed unevenly. The foam stability was 20 minutes for the controls (commercial milks), value that got reduced to 12, 5 and 2.5 min with the addition of 0.0005, 0.001, 0.0025 mg/mL of enzyme.

This work will present a theoretical quantitative atomic-scale mathematical model to understand why FFA molecules play an important role in the stability of milk foams. The model will utilize results of experiments to identify the most important molecular components of the walls of milk foam bubbles. The atomic components of these molecules ─ anticipated to be proteins ─ will be represented by spheres, as is usual in atomic-scale molecular dynamics. Those components contributing to dispersion, electrostatic and hydrogen bonding, interactions with other proteins and with FFA molecules will be identified. These interactions will be treated as “classical” and not “quantum”. One intent is to understand how the protein-FFA interactions can perturb the protein-protein interactions and identify the FFA-concentration dependence of foam stability.

References

Kamath, S., Wulandewi, A., & Deeth, H. (2008). Food Research International, 41, 623–629.

Influence of rheological properties on gastrointestinal digestion and curcumin release of emulsion-filled starch gels

Myeongsu Jo^1,2, Young Jin Choi².

¹Kansas State University, Manhattan, KS, United States
²Seoul National University, Gwanakgu, Seoul, Republic of Korea

Introduction:
For the proper absorption of nutraceuticals encapsulated in emulsions, not only the type and quantity of nutrients but also their digestion rate and release pattern are important. The digestion of curcumin-loaded emulsions and release of curcumin from the emulsions were successfully controlled by adjusting the rheological properties of the emulsion-filled gel system stabilized solely by maize starch.

Method:
Curcumin was loaded in emulsions or emulsion-filled gels stabilized by octenyl succinylated maize starch (OS-MS) in the absence of additional emulsifier or gelling agent. The rheological properties of the emulsion or emulsion-filled gels were adjusted by OS-MS concentration and oil volume fraction. The digestion of curcumin-loaded emulsions and release pattern of curcumin from the emulsion were patterned in a series of oral, gastric, and small intestinal processing. In particular, we considered the digestion of salivary alpha-amylase and gastric lipase in gastric phase, which has been lacking in ascertaining its contribution because it is thought to have less effect on the digestion of starch and lipids compared to pancreatic enzymes.

Discussion:
When OS-MS was only present to encircle the oil droplets, the emulsion system exhibited Newtonian fluids-like flow behavior. As a result, lipase in the stomach and small intestine more easily access the oil surface, causing lipolysis faster, and as a result, the curcumin is rapidly released. On the other hand, in the case of the emulsion-filled gels, as the OS-MS increased, the oil droplet was protected more thickly, so the lipolysis rate of the emulsions and release of curcumin from the emulsions were significantly reduced. In particular, the extent of amylolysis occurring in the gastric phase was significant enough to affect the stability of the emulsion, which in turn affected the lipolysis in the gastric phase and small intestinal phase. This study may help to guide the direction for proper designs of effective oral delivery systems for curcumin using starch-based emulsion systems. Also, this study provides useful information about changes in the ingested starch-based emulsion system through the gastric and small intestinal digestion.

Valorization of canned liquids from Ontario native pulses as egg alternatives

Jessica Chang¹ & Iris J. Joye¹

¹Food Science Department, University of Guelph, N1G 2W1; Guelph, ON; Canada

Introduction/Purpose: Ensuring an inclusive, enriched and sustainable food market from which consumers can meet their needs is an ongoing challenge for food scientists. As concerns regarding allergies, health maintenance, nutrition, animal welfare and environmental sustainability continue to grow, so has the demand for egg-free products. However, with how commonplace eggs are as emulsifying, foaming and gelation agents, the food market has yet to properly meet said demand - particularly for vegan and egg hypersensitive consumers [1]. As a result, malnutrition and lack of variety from egg avoidance diets hinder affected individuals in maintaining quality of life, thus incentivizing research for plant-based egg alternatives [2]. Aquafaba, canned chickpea liquid, has already been valorized as a plant-based foaming agent in baked goods [3]. The theorized foaming and emulsifying properties from proteins, low molecular weight surface active molecules (LMW-SAM) and viscosity-increasing carbohydrates leached during the canning process draw attention to the otherwise discarded liquids of other high protein foods, like pulses [4-6]. As 76% of Ontario’s already large pulse/bean market consists of canned whole beans, it would be prudent to probe the potential value of Ontario-native pulse liquids (PL’s) [7]. The purpose of this project will be to characterize the components of Ontario PL’s and investigate their functionality as egg alternatives. We hypothesize that PL’s would exhibit emulsifying and foaming properties related to their protein and LMW-SAM composition.

Methods and Results: Upon investigation of commercially available PL’s, we confirmed that each commercial liquid indeed exhibited foaming capacity (50 ml, 2000 rpm, 2 minutes): while chickpeas showed a 231%±11 volume increase, black turtle (149%±1), large red (140%±0) and white navy (129%±3) beans had a lower, but still substantial foaming capacity. However, the protein content showed a different order in which black beans had the highest protein content (2.24%±) followed by chickpeas (2.06%±0.18), white navy (1.66%±0.11) and then large red beans (1.58%±0.05). As such, the protein content, though relevant, cannot be the sole determinant of PL’s foaming behavior. This highlights the importance for our project to determine protein composition, structure and size (FTIR, SDS-PAGE and HPLC) and the interactions with other PL constituents like LWM-SAM. These results will be analyzed in view of PL’s emulsifying and foaming capacity.

Significance: By characterizing the composition and testing the functional behaviors of Ontario PL’s, this project has the potential to not only assess the suitability of PL’s for baked goods, but also aid future research into other suitable applications. Such findings can support agricultural sustainability by valorizing a pulse canning waste stream while providing more options for egg-avoiding consumers to achieve their right to an enriched and nutritious diet.

References

¹Miranda J, Anton X, Redondo-Valbuena C, Roca-Saavedra P, Rodriguez J, et al. 2015. Egg and Egg-Derived Foods: Effects on Human Health and Use as Functional Foods. Nutrients. 7(1):706–29.
²Mofidi S. 2003. Nutritional Management of Pediatric Food Hypersensitivity. Pediatrics 111(6): 1645-1653.
³Nguyen TMN, Nguyen NPB, Quoc LPT, Tran GB. 2021. Application of Chickpeas Aquafaba with Pre-treatment as Egg Replacer in Cake Production. Chemical Engineering Transactions. 89:7–12.
⁴Schoeninger V, Coelho SRM, Bassinello PZ. 2017. Industrial processing of canned beans. Ciencia. Rural. 47(5).
⁵McClements DJ & Grossmann L. 2021. A brief review of the science behind the design of healthy and sustainable plantbased foods. Science of Food 2021(5): 17.
⁶Horstmann SW, Linch KM & Arendt EK. 2017. Starch Characteristics Linked to Gluten-Free Products. Foods 2017(6): 29.
⁷Ipsos Reid. 2010. Factors Influencing Pulse Consumption in Canada. Calgary, Alberta: Government of Alberta.

Impact of free calcium and magnesium incorporation to the heat-stability of a model UHT milk with dairy and soy protein

Wei Wang, Martin Chen

Abbott Nutrition R&D Asia-Pacific Center, 20 Biopolis Way, #09-01 Centros Building, Singapore 138668

The stability of high protein ready-to-drink (RTD) milk during heat-treatment is usually a big challenge, especially when mineral salts, such as calcium and magnesium, are fortified in the formulation for nutritional purposes. In this study, we investigated the impact of calcium and magnesium chloride at concentrations of 0, 2, 3.5, 5 and 6.5 mM on physic-chemical properties of a model formulation after heating. The UHT milk model combines milk protein concentrate and soy protein isolate (MPC-SPI) in the formulation, which can be usually found on commercial UHT milks with high protein concentration in the market.

After homogenization and pasteurization, the model milk was dosed with different levels of CaCl2 or MgCl2, respectively, before heat-treatment using the liquid rheometer. The viscosity of the model milk with different levels of salt was measured with a temperature ramp between 20 to 80 degrees Celsius. Increasing of either magnesium or calcium concentration resulted in a more significant increase in viscosity and the milk's medium particle size (D50) after heating, with MgCl2 showing slightly less effectiveness than CaCl2 at higher concentration. More importantly, the change in viscosity and particle size appears to follow a non-linear relationship with the increased mineral level, where a dramatic change in viscosity and particle size was found at 5mM or even higher mineral concentration. LUMsizer analysis showed that the de-stabilization pattern of the sample with high salt concentration was significantly different from their low salt concentration counterparts. This was further verified by the microscope observation of their protein aggregation degree after heating. This study could lay a solid foundation for future nutritional UHT milk development for industrial application

Impact of high concentration dietary fiber substitution on rheological, structural, microstructural, and thermal properties of wheat flour dough

Sabrine DOUIRI^1,2, Achraf GHORBAL³, Wala DHOUIB¹, Khaled CHARRADI⁴, Christophe BLECKER⁵, Hamadi ATTIA² and Dorra GHORBEL^1,2*

¹University of Carthage, INSAT, Centre Urbain Nord, B.P. 676, 1080 Tunis, Tunisia.
²University of Sfax, ENIS, Food Analysis, Valorization, and Safety Laboratory, LAVASA (LR11ES45), BPW 3038, Sfax, Tunisia.
³University of Gabes, ISSAT, Advanced materials, applied mechanics, innovative processes, and environment (UR22ES04), Avenue Omar Ibn El Khattab, 6029 Gabes, Tunisia.
⁴Nanomaterials and Systems for Renewable Energy Laboratory, Research and Technology Center of Energy, Technopark Borj Cedria, BP 095 Hammam-Lif, Tunisia.
⁵University of Liège, GxABT, Passage des Déportés 2, 5030 Gembloux, Belgium.

In the last decades, food trends revolve around the concept of functional food. The tendency for consuming such products is rather prescription-related than a choice of a healthier diet. Diseases such as chronic bowel disease, diabetes, cardiovascular diseases, obesity, and colon cancer that have spread due to the conventional rich in fat, salt, and sugar, poor in fiber diet, have triggered the need for changing our food habits. Recently, there has been a rising trend to add dietary fibers (DF) into cereal products to increase their daily intake by humans. This study assessed the effect of high concentration DF substitution on the rheological, structural, microstructural, and thermal properties of wheat flour dough. Three commercial dietary fibers (pea fiber, insoluble wheat fiber and CMC) were used at different substitution levels, ranging from 3 to 10%, to develop novel high fiber bread flours.

The three fibers were then analyzed for their physicochemical characteristics, X-ray Diffraction, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The effects of DF substitution on the rheological properties of the different novel dough samples were investigated, and results showed that the addition of the three DFs affected various Farinograph parameters. Dynamic tests demonstrated that the dough in all formulations presented viscoelastic behavior. However, compared to the control (simple wheat flour dough), the incorporation of CMC reduced the elastic and viscous moduli. The power-law models were conducted and showed that high enrichment with CMC impaired the rheological properties of wheat flour dough. Indeed, for all dough samples, DF incremented additions increased dough resistance to extension, yet, decreased its extensibility. Also, structural properties of the different obtained doughs were evaluated by FTIR spectroscopy and SEM. Besides, the thermal properties of all formulated doughs were evaluated by differential scanning calorimetry (DSC) and TGA analysis. The obtained DSC-thermograms indicated two starch gelatinization peaks and an amylose-lipid complex dissociation peak, except the dough containing 6% CMC showed a broad climax merging from both gelatinization peaks. No thermal phenomena occurred in the cooling phase for all samples. The TGA results showed that the thermal stability of dough samples depends on the type of the DF and the substitution level

Keywords: Wheat flour dough; dietary fibers; rheology; FTIR; SEM; DSC; TGA.

Moringa peregrina press cake as a novel source of dietary protein and fiber; the effect on in vitro starch digestibility and antioxidant activity of bread

Fatemeh Sardabi¹, Ali Rashidinejad², Mohammad Hossein Azizi³, Hassan Ahmadi Gavlighi⁴

¹Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran
²Riddet Institute, Massey University, Private Bag 11222, Palmerston North, New Zealand
³Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran
⁴Department of Food Science and Technology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran

Moringa peregrina press cake (MPPC), a by-product of its oil extraction, contains high content of protein (43.53%) and fibre (8.72%); nonetheless, its functionality and use as a food ingredient are yet to be explored. Thus, the current study investigated the effect of untreated and debittered (soaked and boiled) MPPC at concentrations of 4, 8, and 16 g/100 g on the enhancement of the nutritional characteristics, in vitro starch digestibility, and antioxidant potential of a functional bread product, before and after digestion. The findings showed that the addition of either untreated or debittered press cake could increase both protein and fibre contents of the bread samples, as well as decreasing their carbohydrate content. Compared to bread samples containing untreated MPPC, those containing the debittered MPPC presented a higher enhancement (p<0.05) of protein and fibre contents, as well as antioxidant properties. Compared to untreated MPPC, its debittered form also resulted in a higher decrease of in vitro starch digestibility. The values for rapidly digested starch were significantly (p<0.05) lower in the case of the debittered MPPC-fortified bread samples, which were also concentration-dependent. However, on the other hand, no significant differences (p>0.05) were observed for the slowly digested starch values of the bread samples after the addition of 4-16 g/100g of either untreated or debittered MPPC.

The total phenolic content (TPC) of debittered MPPC-fortified bread samples increased from 7 to 31% before digestion. Additionally, the addition of both debittered and untreated MPPC increased the DPPH (2,2-Diphenyl-1-picrylhydrazyl) scavenging activity of bread samples by 11.79-30.03% and 1.94-3.74%, respectively, when compared to the control bread. After simulated digestion, the TPC and DPPH scavenging activity of bread samples increased from 724 to 794 and from 10.14 to 47.79%, respectively. Taken together, the findings of this study showed that debittered Moringa peregrina press cake could be used in bread with the potential for glycemic reduction and antioxidant enhancement. These findings will be of interest to the food industry, especially for the manufacture of novel functional food products with low glycemic index and high antioxidant potential

Keywords: Moringa peregrina; Functional bread; Antioxidant activity; Glycemic reduction.

Effects Of Camel Age and Plasticizes On the Properties Of Camel Bone Gelatin Films

A.A. Al-Hassan

Department of Food Science and Human Nutrition, College of Agriculture & Vet. Medicine, Qassim University, 51452, Burydah, Saudi Arabia.

In this study, camel bone gelatin films (CBGF) plasticized with glycerol or sorbitol were developed and evaluated. The camel bone gelatins (Camelus dromedarius) were extracted from three different camel bones of camels aged 2.5, 4.5, and 7 years. The developed films were plasticized with 33% glycerol and 75% sorbitol (w/w) and evaluated for their thickness, light absorption, solubility, moisture sorption–desorption isotherm, water vapor permeability, and the mechanical and thermal properties. The results revealed that the camel ages as well as the plasticizer used had significant (P <0.05) effects on the film properties. The tensile strength values of the films with glycerol (from 0.32 to 0.69 MPa) with the percentage of elongation at break (%EAB) (from 89.42 to 2.68% ) while the TS values of the films with sorbitol (from 2.08 to 3.99 MPa) with %EAB (from 89.42 to 2.68% ) for the gelatin from the bone ages 2.5 to 7 years, respectively. The film color showed the higher lightness values (L) were observed for gelatin films with sorbitol. All samples showed 100% solubility of films with both plasticizers. The moisture sorption and desorption isotherm values increased with increasing the temperature (25, 35 and 45 °C). The gelatin films with sorbitol retained less water compared to the films plasticized with glycerol. In addition, it was observed that the WVP values were lower in the gelatin films from older camel bones (7 years). The thermal analysis of the films using the differential scanning calorimetry (DSC) showed the melting temperature (Tm) ranged from 158.60 - 174.10 °C depends on the camel bone age and the plasticizer. The findings of this study suggest that such films are suitable for applications in food packaging, coatings, and pharmaceutical materials.

Exploring commercial utilization of yellow mustard (sinapis alba l.) gum: stabilization and emulsification in vegetarian mayonnaise and non-dairy fat whipping cream

Ruoyan Liu¹, Xinya Wang², H. Douglas Goff¹, Steve W. Cui²

¹University of Guelph, Canada
²GRDC, Agriculture and Agri-Food Canada

A patented technique has been developed to extract yellow mustard gum (YMG) from yellow mustard bran. The strengths of yellow mustard gum as a new type of mucilage are low cost, and better functional properties such as emulsification, texturizing agent, and stabilization, allowing it to be an effective additive. However, there are only a limited number of YMG products that have been produced through pilot plant, and how the structure-function relationship of YMG applied in commercial products needs to be further investigated.

The challenges of vegetarian mayonnaise are to substitute traditional yolks products while maintaining flavor, texture, and stability. As a complicated emulsion system, whipped cream may undergo serum excretion during resting, and partial coalescence of fat spheres may also lead to emulsion instability. Therefore, the objective of this project is to explore application of YMG in preparation of vegetarian mayonnaise and application of YMG-fenugreek mixed gum in preparation of dairy free whipping cream in order to improve the properties, also investigate the utility of the functional properties of YMG in pilot-produced products.

In this experiment, the physical properties (index of stability, rheological properties, particle size characterization), storage stability (visual stability, microstructure observation, cold tolerance) and texture of YMG-made vegetarian mayonnaise were measured and compared with commercial products to assess the quality and market prospects. The results showed that the vegetarian mayonnaise obtained higher stability, more non-Newtonian flow behavior and smaller droplet size with higher YMG content. After 90 days of storage, no separation occurred in the YMG-added vegetarian mayonnaise. Egg-free mayonnaise containing 0.6% YMG has a similar texture to commercial products and retains better emulsion stability after 90 days of storage.

For whipping cream made by gum mixes, particle size characterization, rheological measurement, and microstructure observation were used to measure whipping cream. Foam properties (serum loss and overrun), textural analysis, and visual stability were used to measure whipped cream. Meanwhile the whipping cream was compared with commercial products. The results indicated that the non-Newtonian flow behavior and droplet size characterization of whipping cream, as well as the overrun of whipped cream, were not significantly related to the gum content, while foam stability and viscosity increased with increasing gum content. Whipping cream containing 0.1% gum mixes has better foam stability than commercial products and a desirable texture. The findings support the market potential of mustard products, bridging the gap between experimental results and applications. The successful application of YMG may prove its potential to be the alternative to commercial gum such as xanthan gum, oat gum or carrageenan for sale, which may give a competitive advantage to Canadian manufacturers in the global marketplace.

Ethyl cellulose-zein based latex films

Jeannine Bonilla, Loong-Tak Lim

Department of Food Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada

This study investigated the effect of zein particles addition, solvent ratios and drying temperature on the film formation behavior of ethyl cellulose (EC) latexes. Zein (4%) particles (SP) was prepared in ethanol: water (70:30 v/v) solvent and subsequently it was stirred for 4 h at 22 °C. Drops of SP were slowly added to water (1:3 v/v, pH 10) to induce precipitation to form a stabilized zein particles (ASP). Separately, EC (4%) solution was prepared in pure ethanol (E100) or 90:10 ethanol:water (w/v) (E90:W10) solvents. Then, either SP or ASP were incorporated into the EC solutions and stirred for 3 h at 22 °C. The resulting dispersions were cast in petri dishes, and dried in an oven at 20 °C or 50 °C at 65% relative humidity to form latex film samples. Physical changes (i.e., color and appearance), Fourier-transform infrared spectroscopy (FTIR) analysis, and atomic force microscopy (AFM, tapping-mode) were studied.

Results revealed that at 20 °C the films containing pure ethanol, without (E100) and with (E100-SP, E100-ASP) particles were white color in appearance and brittle, and that an increase in the drying temperature (50 °C) allowed to obtain more homogeneous, flexible, and transparent films. The incorporation of 10% water (E90:W10) as solvent resulted in white colored films at both temperatures. Moreover, at 20 °C, all the films (E90:W10, E90:W10-SP, E90:W10-ASP) exhibited “foamy” microstructures, while at 50 °C these films appear to stratified into zein/EC polymer layers. In addition, FTIR analysis showed changes in the intensity and position of the peaks, depending on the temperature and/or solvent used, suggesting interaction between these two polymers. Finally, phase images obtained by tapping-mode AFM showed that ASP particles were smaller and more uniformly dispersed as compared to SP particles. The phase images showed that at 20 °C, E100 films with either SP or ASP appear to be surrounded by EC polymer. In addition, the incorporation of water (E90:W10) induced substantial microstructural heterogeneity (pores or cracks). On the other hand, at 50°C, all E100 films exhibited enhanced particle adhesion, which was consistent with the increased optical transparency of these films.

In summary, this study shows the effect of particle addition, solvent ratio, and temperature on the microstructure of zein-EC latex films. The use of E90:W10 as solvent and a minimum formation temperature of 50°C is promising to obtain self-stratification films from EC-zein polymers.

Imaging techniques to characterize pulse-based extruded food products: A review

Xiang Li¹, Annamalai Manickavasagan² and Loong-Tak Lim¹

¹Department of Food Science, University of Guelph, Guelph, Ontario, N1G 2W1, Canada
²School of Engineering, University of Guelph, Guelph, Ontario, N1G 2W1, Canada

The increasing demand for plant protein foods has created awareness about pulses among consumers. However, long cooking time, unpleasant side effects (e.g., flatulence), and the lack of commercial products remain a hurdle to promote the consumption of pulses. To address these issues, processing of pulses through extrusion has been applied to reduce antinutrients, improve protein digestibility, and also increase the diversity of pulse-based products. Pulse-based extruded food products can be categorized into expanded (e.g., expanded snacks) or texturized products (e.g., meat analogues). The high protein content of pulses tends to impair the microstructure and sensorial texture of the expanded extrudates. The principle of protein texturization has not been fully understood for texturized extrudates. Therefore, pulse-based extruded food products require accurate, insightful, and multi-dimensional characterization for effectively monitoring the changes of ingredients, optimizations of process parameters, enhancing product qualities. Most quality attributes of pulse-based extruded food products are measured by conventional analytical methods such as chemical and molecular analyses. In many situations, the lack of micro structural characterization techniques affect the process optimization in extrusion process and also the development of innovative products. With the advanced development of optical sensors, image processing protocols, and artificial intelligence approaches, image-based techniques have benefited food quality characterization to a great extent. This review covered three imaging techniques (i.e., scanning electron microscopy (SEM), X-ray computed tomography (CT) and confocal laser scanning microscopy(CLSM)) that have been successfully used to characterize the quality of pulse-based extruded food products, including their applications, advantages, disadvantages, and improvement. Other potential imaging techniques (i.e., computer-vision based RGB imaging, multispectral imaging, visible-near infrared hyperspectral imaging, transmission electron microscopy and diffusion tensor imaging) were also discussed, aiming to assess pulse-based extrudate quality with full spectrum of attributes and deeper understanding. SEM allows surface morphological analysis of extrudates. However, 2D SEM micrographs are mainly useful for qualitative analysis. The complex SEM sample preparation process can be simplified by using variable pressure SEM. Results from CT studies of cellular microstructure of expanded extrudates can be correlated with extrudates’ textural properties. X-ray phase-contrast tomography has higher sensitivity than CT with great potential for characterizing the fibrous structure of texturized extrudates. CLSM is useful for characterizing the structural changes and interactions of protein and starch in the extrudates. Reflectance mode-CLSM has potential for measuring the fibrous structure of texturized extrudates. Other than these three imaging technologies, computer-vision based RGB imaging and multispectral imaging could quantify the extrudates’ color. Visible-near infrared hyperspectral imaging, transmission electron microscopy, and diffusion tensor imaging are all promising for characterizing the fibrous structure of protein-texturized extrudates. Overall, these imaging techniques are promising for the characterization of key quality attributes of pulse-based extruded food products.

16th IHC posters

16^th IHC posters