Alain Doyen

Laval University | ULAVAL · Department of Food and Nutrition Sciences

Holder pasteurization (HoP) (62.5 °C, 30 min) of donor human milk is widely used to inactivate potential pathogens but may lead to denaturation and aggregation of bioactive proteins, reducing their functionality. In contrast, high pressure processing (HPP) is a non-thermal technique that minimally affects assessed bioactive components; however, it...

The impact of ultra-high pressure homogenization (UHPH) (175 and 300 MPa, 1 and 4 passes) on the structure of egg yolk granule was evaluated to improve the techno-functional properties of the proteins. The UHPH treatment destabilized and modified the structure of egg yolk granule proteins, which was validated by protein profiles from gel electropho...

A growing interest in pulse proteins in recent years results from their crucial role in the transition toward sustainable food systems. Consequently, current research is mainly focused on the production of protein ingredients and the evaluation of their nutritional and techno-functional properties for the development of animal product analogues. Ho...

In addition to improving shelf life while preserving the nutritional quality of food, high-pressure processing is gaining interest for the production, separation, and extraction of high-value compounds such as proteins. Through its effect on the matrix structure, high-pressure technology is improving penetration of extraction solvent within the cel...

When there is an inadequate supply of mother’s milk, pasteurized donor human milk is preferred over formula to supplement feeds for preterm infants. Although providing donor milk helps to improve feeding tolerance and reduce necrotizing enterocolitis, changes to its composition and reductions in bioactivity during processing, are thought to contrib...

The impact of high temperature short time (HTST, 72 °C, 15 s), Holder pasteurization- (63 °C, 30 min) and high hydrostatic pressure (HHP, 600 MPa-10 min) was evaluated on the digestibility of human milk protein concentrate (HMPC) by using a static in vitro gastrointestinal digestion system. The results showed that the processing steps used to produ...

Background: Gestational diabetes mellitus (GDM) is known to affect human milk composition. Aims of this study were to compare macronutrient and energy content of human milk of women with (GDM+) and without GDM (GDM-), to assess the association between maternal health and human milk macronutrient and energy content and association between human milk...

This study investigated the effects of pasteurization methods (Holder -HoP, high-temperature short-time – HTST, and high hydrostatic pressure – HHP) and centrifugation conditions (1700, 3800 and 10 000 g for 5, 10 and 15 min) on protein distribution between cream and skim milk (SM). HHP prior to skimming led to lower cream protein content (46 g/kg,...

The defatting of legume flours with hexane is usually the first step in producing protein-rich ingredients. However, its impact on protein profiles, zeta potential, surface hydrophobicity and techno-functionality of pea proteins has not been evaluated. Consequently, this work aimed to evaluate the impact of the hexane defatting step on pea protein...

Pressure-driven membrane separation processes have been integrated as unit operations in cheese manufacturing for decades. Concentrated systems obtained from membrane separation processes are nowadays used in cheesemilks for milk protein standardization, enrichment and even up to the preparation of liquid pre-cheeses. Recent innovations focus on de...

Our study aimed to investigate the impact of various emulsifiers, namely whey protein isolate (WPI), soy protein isolate (SPI), and Tween 80 (Tw), on their ability to encapsulate cannabis oil with maltodextrin as the wall material. The physicochemical properties of the powder, the stability of the cannabinoids, and their bioaccessibility during sta...

Ultrafiltration (UF) and reverse osmosis (RO) are commonly used for the clarification and concentration of fruit juices. However, one of the main limitations of filtration membranes is biofouling, which reduces membrane efficiency and can contaminate the filtered product and lead to spoilage. In this study, the microbial fouling layers of UF and RO...

High hydrostatic pressure (HHP) treatment induces structural changes in bovine milk proteins depending on factors such as the temperature, pH, concentration, decompression rate, cycling, composition of the medium and pressure level and duration. An in‐depth understanding of the impact of these factors is important for controlling HHP‐induced modifi...

Pasteurized donor human milk is recommended for hospitalized preterm infants when mother’s own milk is unavailable. Our aim was to compare the antiviral activity of human milk processed by Holder pasteurization (HoP) or high-pressure processing (HPP) against representative enveloped and non-enveloped viruses including cytomegalovirus and hepatitis...

Treatment of dairy white wastewater (WW) by reverse osmosis (RO) is usually performed to generate process water and to reclaim dairy components for their valorization. For this study, a mixture of pasteurized milk and WW from a dairy plant was concentrated by RO to achieve a protein concentration similar to that of skimmed milk. Retentates, which a...

Processing edible insects into protein extracts may improve consumer acceptability. However, a better understanding of the effects of food processing on the proteins is needed to facilitate their incorporation into food matrices. In this study, soluble proteins from Tenebrio molitor (10% w/v) were pressurized using high hydrostatic pressure (HHP) a...

Ultra-high pressure homogenization (UHPH) is a promising method for destabilizing and potentially improving the techno-functionality of the egg yolk granule. This study's objectives were to determine the impact of pressure level (50, 175 and 300 MPa) and number of passes (1 and 4) on the physico-chemical and structural properties of egg yolk granul...

This work evaluated the impact of high temperature short time (HTST, 72°C, 15s), high hydrostatic pressure (HHP, 400-600 MPa at 5 and 10min) and Holder pasteurization (HoP, 62.5°C, 30min) on protein profile and aggregation in a human milk protein concentrate (HMPC). The structural changes induced in milk proteins were investigated in HMPC as well a...

The effect of high pressure processing (HPP) compared to Holder pasteurization (HoP) (62.5 °C, 30 min), on the inactivation of cytomegalovirus (CMV) and hepatitis A virus (HAV) inoculated human milk pools (n = 10) and culture media (n = 3) was studied. Samples were retained as untreated controls, treated by HoP (62.5 °C, 30 min) or with one of six...

The effect of RO concentration on microbial ecosystem changes and the chemical composition of white wastewaters (WW; dairy effluents generated during the hydraulic flush of dairy processes), recovered from two dairy plants (A and B), was evaluated. The WW of dairy plant A was dominated by psychrotrophic bacteria, but no increase of the total number...

The disposal of solid and liquid processing waste is an important challenge for the seafood industry. These wastes can often be turned into valuable products. Liquid wastes like cooking juices can be useful for the food industry, once concentrated and stabilized, because they contain molecules such as proteins, pigments and flavor compounds. The pr...

Background In Western societies, the acceptability of entomophagy is low despite the sustainable and nutritional benefits of insects. It is recognized that insect meals incorporated in into familiar foods increases willingness to eat insects. Chefs can offer positive culinary insect-based experiences to their customers which can then contribute to...

The dairy industry produces large amounts of wastewater, including white and cleaning wastewater originating principally from rinsing and cleaning-in-place procedures. Their valorization into process water and non-fat milk solids, in the case of white wastewater, or the renewal of cleaning solutions could be achieved using pressure-driven membrane...

Background Bovine milk–based protein modulars are currently available to nutrient-enrich enteral feedings; however, they have limitations for use in very-low-birth-weight infants. Objectives Our objectives were to develop a human milk–based protein (HMP) concentrate and to conduct a preclinical assessment of the HMP concentrate in weanling rats....

Self-assembling peptides have gained attention because of their nanotechnological applications. Previous work demonstrated that the self-assembling peptide f1-8 (Pf1-8) that is generated from the tryptic hydrolysis of β-lactoglobulin can form a hydrogel after several purification steps, including membrane filtration and consecutive washes. This stu...

This study aimed to quantify the effects of biofouling on the performance of an ultrafiltration system during 24-h recirculation of whey solutions at 0 and 0.8% (w/v) protein. Biofouling by Streptococcus thermophilus and the intrinsic microflora of the ultrafiltration system was either allowed or inhibited with 10 mm sodium azide. Permeate fluxes w...

This study aimed to quantify the contribution of Streptococcus thermophilus cell deposition to the flux decline observed during ultrafiltration of cheese whey constituents using an unstirred batch cell system. Bacterial cells were suspended in model solutions of sodium chloride, of sodium chloride supplemented with either whey protein isolate, β-la...

Optimizing protein intake for very low birth weight (<1,500 g) infants is fundamental to prevent faltering postnatal growth with the potential association of impaired neurodevelopment. The protein content of human milk is not sufficient to support the growth of very low birth weight infants. To meet their elevated protein requirements, human milk i...

Cranberries, mainly processed as juice, have garnered interest over the past decade due to their high content of phytochemical compounds related to promising health benefits. To meet consumer expectations, a juice clarification step is usually incorporated to remove suspended solids. The use of pectinolytic enzyme and membrane processes are commonl...

Inclusion of edible insects in human diets is increasingly promoted as a sustainable source of proteins with high nutritional value. While consumer acceptability remains the main challenge to their integration into Western food culture, the use of edible insects as meal and protein concentrate could decrease neophobia. The defatting of edible insec...

The low consumer acceptance to entomophagy in Western society remains the strongest barrier of this practice, despite these numerous advantages. More positively, it was demonstrated that the attractiveness of edible insects can be enhanced by the use of insect ingredients. Currently, insect ingredients are mainly used as filler agents due to their...

Pressure-driven membrane separation processes are commonly used in cheese milk standardization. Using ultrafiltration (UF) or microfiltration (MF), membrane separation processes make it possible to concentrate the milk proteins and increase the yields of cheese vats. However, the contribution of membrane separation processes to the environmental im...

Reverse osmosis (RO) is essential for dairy processors to reduce their water input and the energy dedicated to dewatering processes such as evaporation. Indeed, water can be reclaimed by RO from numerous dairy fluids (e. g., milk, cheese whey, UF permeates, condensing water), but these applications may have different effects on plant efficiency in...

The goal of this study was to optimize an innovative ultrahigh-pressure–assisted extraction method for phenolic compounds of date palm (Phoenix dactylifera L.) using response surface methodology (RSM). A four-factor-three-level Box–Behnken design (BBD) was used to test the following extraction parameters: ethanol concentration (X1), solvent to samp...

Despite extensive research on the topic, valorization of dairy by-products remains challenging. Cheese whey is of particular interest because it contains valuable proteins such as α-lactalbumin (α-LA) and β-lactoglobulin (β-LG). However, selective fractionation of these 2 proteins into pure fractions is complex because of their similar molecular we...

Edible insects have garnered increased interest as alternative protein sources due to the world’s growing population. However, the allergenicity of specific insect proteins is a major concern for both industry and consumers. This preliminary study investigated the capacity of high hydrostatic pressure (HHP) coupled to enzymatic hydrolysis by Alcala...

Separation of α-lactalbumin and β-lactoglobulin improves their respective nutritional and functional properties. One strategy to improve their fractionation is to modify their pH and ionic strength to induce the selective aggregation and precipitation of one of the proteins of interest. Electrodialysis with bipolar membrane (EDBM) is a green proces...

The separation of α-lactalbumin (α-LAC) and β-lactoglobulin (β-LG) by ultrafiltration (UF) is a technological challenge due to their similar molecular size. As high hydrostatic pressure (HHP) treatment generates β-LG complexes of a larger molecular size than native β-LG, it was suggested that pressurization of skim milk could improve the separation...

Egg yolk granule phosvitin (45 kDa) is a phosphoprotein known for its emulsifying properties. Recently, high hydrostatic pressure (HHP) treatment of granule induced the transfer of phosvitin to the soluble plasma fraction. This project evaluated the performance of the ultrafiltration (UF) used to concentrate phosvitin from the plasma fraction to pr...

Egg yolk phosvitin is of particular interest due to its functional and biological properties. Recently, it was demonstrated that high hydrostatic pressure (HHP) (400 MPa for 5 min) induced the transfer of folic acid and phosvitin from the egg yolk granule to the plasma fraction. A granule fraction (Gin) produced by egg yolk centrifugation was press...

Over the past decade, the potential of edible insects as a novel ingredient in high value-added products has been investigated to find alternatives to conventional protein sources that are expensive, over-exploited and harmful to the environment. This review assesses the state of insects as an alternative protein source from production to consumpti...

Edible insects represent an interesting alternative source of protein for human consumption but the main hurdle facing the edible insect sector is low consumer acceptance. However, increased acceptance is anticipated when insects are incorporated as a processed ingredient, such as protein-rich powder, rather than presented whole. To produce edible...

Milk protein concentrates (MPC) are increasingly used as protein fortifiers in food formulations, as a means to increase cheese yield, and in the manufacture of Greek-style yogurt. However, manufacturing of MPC requires significant volumes of input water and generates polluting by-products such as permeates and/or diafiltrates. Reverse osmosis was...

Background: Seafood processing generates significant amounts of solid and liquid waste in the environment. These represent a potential source of high-value biomolecules for food, pharmaceutic and cosmetic applications. There are very few studies on the valorization of wastewaters compared to solid by-products. However, cooking waters are character...

Ultrafiltration (UF) and microfiltration (MF) are widely-used technologies to standardize the protein content of cheesemilk. Our previous work demonstrated that protein retention of a 0.1-µm MF spiral-wound membrane (SWM) was lower, but close to that of a 10 kDa UF one. Considering that the permeability of MF membranes is expected to be higher than...

Human donor milk (DM) is Holder pasteurized (62.5°C, 30 min) to ensure its microbiological safety for infant consumption. In low-resource settings, flash-heating is used to pasteurize milk. While there is considerable interest in non-thermal alternatives (high hydrostatic pressure processing [HHP] and UV-C irradiation) for pasteurization, their eff...

Black soldier fly (BSF) larvae represent a promising alternative ingredient for animal feed. Post-production processing can, however, affect their quality. This project aimed to optimize larval killing by comparing the effects on the nutritional and microbiological quality of 10 methods, i.e., blanching (B = 40 s), desiccation (D = 60 °C, 30 min),...

Galactooligosaccharides (GOS) are prebiotics commonly produced from lactose via an enzymatic reaction cat-alyzed by β-galactosidase (β-gal) which is present in many organisms, including microalgae. Whey permeate (WP), a major byproduct of the dairy industry rich in lactose, represents an interesting medium for producing GOS as high value-added ingr...

The temperature of the feed is known to be an important factor affecting the formation and the growth rates of bacterial communities on dairy filtration membranes. However, decades after the integration of filtration processes in the dairy industry, there is still questioning whether filtration should be performed at cold (<15 °C) or hot (>48 °C) t...

Background: When mother's milk is insufficient, pasteurized human donor milk (DM) is the recommended supplement for hospitalized very-low-birth-weight infants. The current method of pasteurization (Holder, 62.5°C, 30 min) negatively affects heat-sensitive nutrients and bioactive proteins. Objectives: Objectives of this study were to compare chan...

β-Galactosidase is a commercially important enzyme widely used in the food industry for the manufacturing of lactose-hydrolyzed products and synthesis of probiotic food ingredients. It could also be used to reduce the environmental impacts of the dairy industry relative to lactose disposal. This enzyme has been isolated from different sources, with...

The development of stable macromolecular structures with tailored functional properties in the dairy industry using innovative stabilizers is of great interest. The self-assembling peptide f1-8 (Pf1-8) derived from β-lactoglobulin was found to interact with whey proteins, consequently changing their physicochemical properties. The objective of the...

Exploration of innovative high hydrostatic pressure (HHP)-assisted enzymatic hydrolysis of plant based food proteins may help improve peptide yield and bioactivity of hydrolysates. In this study, we performed enzymatic hydrolysis of flaxseed proteins using trypsin under HHP (100 and 300 MPa for 5 and 10 min) to evaluate the effect of presurization...

Ultrafiltration (UF) can be used to concentrate yogurt to produce Greek-style yogurt (GSY) (UF-YOG), but this generates acid whey permeate, which is an environmental issue. However, when UF is applied before fermentation (UF-MILK), a nonacidified whey permeate is generated. For this study, two model GSYs (UF-YOG and UF-MILK) were produced to compar...

Fractionation of β-lactoglubulin (β-lg) and α-lactalbumin (α-la) using conventional separation technologies remains challenging mainly due to similar molecular weight. Herein, casein (CN) was used as ligand protein to specifically aggregate β-lg under high hydrostatic pressure (HHP) in order to separate α-la after acidification to pH 4.6. Specifica...

High hydrostatic pressure (HHP) and electrodialysis with ultrafiltration membranes (EDUF) are two efficient technologies used respectively to improve protein enzymatic hydrolysis and recovery of bioactive peptides, but they have never been tested together. Hence, in this study, HHP pre-treatment was performed on defatted flaxseed protein isolate pr...

High-milk protein concentrates (>80% on a dry weight basis) are typically produced by ultrafiltration (UF) with constant-volume diafiltration (DF). To maximize protein retention at a commercial scale, polymeric spiral-wound UF membranes with a molecular weight cut-off (MWCO) of 10 kDa are commonly used. Flux decline and membrane fouling during UF h...

Protein aggregation can be used to improve functionality in certain food systems, especially in gelled systems. However, in beverages application, this phenomenon is generally undesirable since it is usually related to protein insolubility and turbidity. Nonetheless, some research has demonstrated a molecular chaperone-like property of certain milk...

High hydrostatic pressure-assisted enzymatic digestion of β-LG accelerated protein digestion but drastically modified the resulting peptide profile, which may affect the performance of ultrafiltration (UF) which is used to fractionate the hydrolysates. Consequently, the aim of this work was to evaluate the change in UF performance of tryptic hydrol...

Disposal of whey, a co-product generated from dairy industries, remains an important worldwide problem. However, considering its composition in high value proteins, some technological strategies emerged for its optimal valorization. Separating alpha-lactalbumin (α-la) from beta-lactoglobulin (β-lg), the two major whey proteins (WP), remains quite c...

Polypeptide/solid charged surface interactions are omnipresent in the biomedical and biochemical fields. The present study aimed to understand the adsorption mechanisms of a cation-exchange membrane (CEM) by a well-characterized peptide mixture at three different pH values. Results demonstrated that fouling was important at pH 6, twice lower at pH...

Peptide fouling occurring on anion- (AEMs) and cation-exchange membranes (CEMs) is one of the most serious issues of conventional electrodialysis (ED) process for hydrolysate demineralization. Nonetheless, recent studies discussed the advantages of non-conventional ED phenomena such as water splitting and electroconvection on decreasing scaling and...

Microfiltration is largely used to separate casein micelles from milk serum proteins (SP) to produce a casein-enriched retentate for cheese making and a permeate enriched in native SP. Skim milk microfiltration is typically performed with ceramic membranes and little information is available about the efficiency of spiral-wound (SW) membranes. We d...

High hydrostatic pressure (HHP), used alone or with other processes, is an emerging technology increasingly used in the food industry to improve microbial safety, and the functionality and bioactive properties of food products. HHP provides a way to reduce energy requirements for food processing and may contribute to improved energy efficiency in t...

Ultrafiltration (UF) is largely used in the dairy industry to generate milk and whey protein concentrate for standardization of milk or production of dairy ingredients. Recently, it was demonstrated that high hydrostatic pressure (HHP) extended the shelf life of milk and improved rennet coagulation and cheese yield. Pressurization also modified cas...

The present work characterized the effects of pre-treatments on the protein profile and microstructure of granule fractions from egg yolk. The granule microstructure was studied using confocal laser scanning microscopy (CLSM). The protein profiles of the pre-treated granule and the corresponding plasma fraction were studied using 2D gel electrophor...

Biofouling of filtration membranes is a major quality and performance issue for the dairy industry. Because biofilms that survive cleaning cycles become resistant over time, prevention strategies limiting the adhesion of bacteria to membranes should be prioritized for sustainable control of biofouling. However, this cannot be achieved because the p...

Few data are available concerning the composition of biofilms found at the surface of filtration membranes, which, to some extent, explains the long-term failure of numerous strategies developed to control biofouling. This preliminary study intended to design a metagenomic tool targeting the 16S rRNA gene in order to unravel a general portrait of b...

The effect of high hydrostatic pressure (HHP) on flaxseed protein structure and peptide profiles, obtained after protein hydrolysis was, investigated. Isolated flaxseed protein (1%, m/v) was subjected to HHP (600 MPa, 5 min or 20 min at 20 °C) prior to hydrolysis with trypsin only and trypsin-pronase. The results demonstrated that HHP treatment ind...