Development and Performance Evaluation of Biomass-Based Injera Baking Gasifier Stove: A Case Study of Clean Cooking Technologies in Ethiopia.

The primary energy source in Ethiopia is biomass. Over 80% of Ethiopians are rural dwellers who rely on biomass energy for lighting and cooking. In most parts of Ethiopia, injera is traditionally baked using an open fire, a three stone, or a device using woody biomass. These baking stoves have very low efficiency and consume a significant amount of fuel. Moreover, these traditional baking stoves have released large amounts of indoor air pollution, which has led to different types of health-related risks, especially for women and children in the country. Therefore, the aim of this study was to investigate efficient and fuel-saving injera baking technologies. Rigorously, an injera baking gasifier stove was designed, developed, and characterized in detail through water boiling and control cooking test methods. The indoor air pollution level was evaluated using particulate matter measuring instruments. The result indicated that the developed gasifier stove had a thermal efficiency of 21.8%. Furthermore, an 86% fuel savings performance was demonstrated by the controlled cooking test for the injera baking gasifier stove. The average emission concentrations of particulate matter and carbon monoxide were 608 µg/m3 and 9 ppm, respectively, during indoor air pollution determination. The study showed that injera baking gasifier stoves are a promising cooking technology for societies where baking is mostly dependent on traditional biomass fuel.

Sterol Migration during Rotational Frying of Food Products in Modified Rapeseed and Soybean Oils.

This study explores the impact of rotational frying of three different food products on degradation of sterols, as well as their migration between frying oils and food. The research addresses a gap in the existing literature, which primarily focuses on changes in fat during the frying of single food items, providing limited information on the interaction of sterols from the frying medium with those from the food product. The frying was conducted at 185 ± 5 °C for up to 10 days where French fries, battered chicken, and fish sticks were fried in succession. The sterol content was determined by Gas Chromatography. This research is the first to highlight the influence of the type of oil on sterol degradation in both oils and food. Notably, sterols were found to be most stable when food products were fried in high-oleic low-linolenic rapeseed oil (HOLLRO). High-oleic soybean oil (HOSO) exhibited higher sterol degradation than high-oleic rapeseed oil (HORO). It was proven that cholesterol from fried chicken and fish sticks did not transfer to the fried oils or French fries. Despite initially having the highest sterol content in fish, the lowest sterol amount was recorded in fried fish, suggesting rapid degradation, possibly due to prefrying in oil with a high sterol content, regardless of the medium used.

Effects of pre-formulation and post-cooking method on the rheological and gelation properties of 3D printed chicken products.

This study investigated the influence of oil type (olive, soybean, and peanut oil) and post-cooking methods (oven bake and microwave) on the quality of 3D printed chicken meat products. The Ostwald-de-Waele model was used to describe the flow behavior of chicken meat paste (R2 > 0.995). Oil-fortified groups present significantly lower consistency index (K) and flow behavior index (n), indicating better fluidity. A modified Cox-Merz rule was applied by multiplying angular frequency with shift factors (αSF). Surprisingly, the values of αSF are well-correlated with accuracy parameters of 3D printed cubes (|r| >0.8). For post-heating methods, baking results in higher fluid loss but contributes to a smoother surface. The microwaved gels showed better fluid retention ability and higher accuracy but lost the detail shape of the 3D printing model. Overall, the PO (peanut oil) meat emulsion group presented better textural properties and flat surfaces than other oil-added counterparts.

Effects of seasoning addition and cooking conditions on the formation of free and protein-bound heterocyclic amines and advanced glycation end products in braised lamb.

The accumulation of heterocyclic amines (HAs) and advanced glycation end products (AGEs) in thermally processed meats has been arising safety concerns. The effects of cooking conditions and seasoning addition on the formation of HAs and AGEs in Chinese traditional braised lamb were investigated by UPLC-MS/MS analysis. Soy sauce significantly increased the formation of HAs and AGEs, among which light soy sauce had the greatest promoting effect (69.45-15300.62 %). Conversely, spices inhibited HAs and AGEs formation, the inhibition rate of free HAs and AGEs reached 22.06-34.72 % when using 70 % ethanol extract. Hot blanching treatment and adding soy sauce and spices at a later stage could significantly suppress HAs and AGEs production. Flavonoids, including galangin, hesperidin, narirutin, etc., were identified as key effectors in spices. These findings help to promote awareness of the formation of HAs and AGEs in braised lamb and provide valuable insights for optimizing processing techniques to minimize their production.

Thermomechanical transitions of meat-analog based fried foods batter coating.

This study aimed to characterize the thermomechanical transitions of meat-analog (MA) based coated fried foods. Wheat and rice flour-based batters were used to coat the MA and fried at 180 °C in canola oil for 2, 4 and 6 min. Glass-transition-temperature (Tg) of the coatings were assessed by differential scanning calorimetry, directly after frying or after post-fry holding. Mechanical texture analyzer and X-ray microtomography were employed to assess textural attributes and internal microstructure, respectively. Batter-formulation substantially impacted the Tg of fried foods coating i.e., crust. Tg of fried foods crust were ranged between -20 °C to -24 °C. Tg was positively correlated with frying time and internal microporosity (%), whereas negatively correlated with moisture content. Internal microstructure greatly influenced the textural attributes (hardness, brittleness, crispiness). Post-fry textural stability considerably impacted by Tg. Negative Tg value explains post-fry textural changes (hard-to-soft, brittle-to-ductile, crispy-to-soggy) of MA-based coated products at room-temperature (25 °C) and under IR-heating (65 °C).

Association between cooking fuel exposure and respiratory health: Longitudinal evidence from the China Health and Retirement Longitudinal Study (CHARLS).

The epidemiological evidences for the association between cooking fuel exposure and respiratory health were inconsistent, and repeated-measures prospective evaluation of cooking fuel exposure was still lacking. We assessed the longitudinal association of chronic lung disease (CLD) and lung function with cooking fuel types among Chinese adults aged ≥ 40 years. In this prospective, nationwide representative cohort of the China Health and Retirement Longitudinal Study from 2011 to 2018, 9004 participants from 28 provinces in China were included. CLD was identified based on self-reported physician diagnosis in 2018. Lung function was assessed by peak expiratory flow (PEF) in 2011, 2013 and 2015. Multivariable logistic and linear mixed-effects repeated-measures models were conducted to measure the associations of CLD and PEF with cooking fuel types. Three-level mixed-effects model was performed as sensitivity analysis. Among the participants, 3508 and 3548 participants used persistent solid and clean cooking fuels throughout the survey, and 1948 participants who used solid cooking fuels at baseline switched to clean cooking fuels. Use of persistent clean cooking fuels (adjusted odds ratio [aOR] = 0.73, 95 % confidence interval [CI]: 0.61, 0.88) and switch of solid fuels to clean fuels (aOR = 0.81, 95 % CI: 0.67, 0.98) were associated with lower risk of CLD. The use of clean cooking fuels throughout the survey and switch of solid fuels to clean fuels in 2013 were also significantly associated with higher PEF level. Similar results were observed in stratified analyses and different statistical models. The evidence from CHARLS cohort suggested that reducing solid cooking fuel exposure was associated with lower risk of CLD and better lung function. Given the recent evidence, improving household air quality will reduce the burden of chronic lung diseases.

Experimental evaluation of the impact of ventilation on cooking-generated fine particulate matter in a Chinese apartment kitchen and adjacent room.

Cooking is one of the major contributors to indoor pollution. Fine particulate matter (PM2.5) produced during cooking commonly mix into adjacent rooms and elevates indoor PM2.5 concentrations. The risk of human exposure to cooking-generated PM2.5 is mainly related to the exposure duration and particulate matter (PM) concentration. The PM2.5 concentration is influenced by cooking methods and ventilation patterns. Range hoods and open windows are conventional strategies for lowering the concentration of cooking-generated particles. To decrease PM emissions, kitchen air supply systems have been proposed, providing alternative possibilities for kitchen ventilation patterns. The effects of cooking methods, air supply systems, range hoods, and windows on PM2.5 concentrations must be analyzed and compared. To understand and provide advice on reducing exposure to PM2.5 due to cooking activities, we measured the PM2.5 mass concentration in a kitchen and adjacent room during cooking. The identified factors, including cooking method, range hood use, window status, and air supply system, were varied based on orthogonal design. The delay time between the PM2.5 peak in the kitchen and that in the adjacent room was determined. The degree of exposure risk for cooking-generated PM2.5 was evaluated using the mean exposure dose. The results indicated that the mean PM2.5 mass concentration in the kitchen ranged from 22 to 2296 µg/m3. In descending order, the factors affecting the indoor PM2.5 concentration in the apartment studied were range hood use, cooking methods, window status, and air supply system. The PM2.5 peak in the adjacent room occurred 200-800 s later than that in the kitchen. Other conditions being constant in these experiments, the use of range hoods, air supply systems, and windows reduce exposure doses by 90%, 37%, and 51%, respectively. These research results provide insights for reducing human exposure to cooking-generated PM2.5.

[Study of composite mixtures based on durum wheat semolina and white beans flour for pasta production as specialized food products].

Increasing the number of chronic non-communicable diseases around the world is a critical social problem in many countries. In this regard, the creation of specialized foods that correct dysfunctions of the human body is a priority direction in science and food industry. Legumes are characterized by a high content of protein, minerals and trace elements, which determines their possible use as the main raw materials for creating specialized foods. The aim of this research was to present a medical, biological and technological justification for the possibility of producing pasta based on composite mixtures of durum wheat semolina and white bean flour as specialized foods with increased protein content and optimal mineral ratio. Material and methods. The objects of the study were grains of durum wheat (grade Krasnokutka-13), whole meal flour from white beans, composite mixtures in various percentages, and pasta from them. The nutritional and biological value of durum wheat semolina and bean flour was determined experimentally, the nutrient profile of the developed composite mixtures - by calculation. The rheological properties of dough from composite mixtures and the cooking properties of pasta made from them were assessed. Results. It has been established that increase in the proportion of white bean flour in composite mixes elevated calcium and protein content, optimized an amino acid profile, the ratio of calcium to phosphorus, significantly reduced the glycemic load. Bean flour introduction into composite mixtures positively affected the rheological properties of the dough and products from it, in particular, on the speed and energy intensity of dough kneading and aging processes of starched polysaccharides, however, lead to a decrease in dry pasta strength. The pasta made from composite mixtures meets the technological requirements for pasta in terms of a number of basic indicators, namely: the volume of dry pasta, the volume of pasta after cooking and the boilability coefficient. Conclusion. The rheological and technological properties of composite mixtures and their nutrient profile make it possible to recommend them for the production of pasta, as specialized foods.

The Knowledge and Practices Toward Food Safety Measures at Home in the Lebanese Community.

Hygienic measures practiced at home are highly related to the occurrence of food-borne diseases during food production, storage, and handling. Contaminated food remains a major cause of several diarrheal diseases, hospitalizations, and spikes in medical expenses. In our current study, we aimed to assess the knowledge of food safety and the food safety and hygiene practices at home among the Lebanese population. A cross-sectional study was conducted through an online questionnaire including two sections. The first section included socio-demographic characteristics of participants, whereas the second section included questions related to practices and knowledge about food safety, divided into five parts; personal hygiene practices, dry and cold storage, sanitizing and cleaning and food intoxication. A total of 1101 Lebanese above 18 years participated and provided their responses to the questionnaire. Overall, the majority of participants had fair knowledge about food safety where 96.8% of the participants answered correctly about preventing microbial growth on food. 77.9% of those participants acquired their knowledge about food safety from articles, workshops, or the internet. Moreover, females, people with children and those who cook for themselves scored significantly higher than others (68.8, 70.6, and 70%, respectively). In comparison to younger participants (67.8%), older participants (50+ and 30-49) scored higher at 69.7% and 68.9%, respectively. Higher scores were obtained for questions related to storing dried foods/meat and poultry products with percentages 91.4 and 87.8%, respectively. However, lower scores were noticed on questions related to washing raw chicken before handling and storing eggs (9.7 and 12.3%, respectively). Altogether, our results revealed the need for directed food safety awareness campaigns at the national level to educate the Lebanese community about domestic food handling practices. We believe these campaigns can significantly reduce related diseases and hospitalizations.

Promoting Nutrition and Food Sustainability Knowledge in Apprentice Chefs: An Intervention Study at The School of Italian Culinary Arts-ALMA.

Chefs' decisions can greatly improve the quality of food provided and positively guide diners' choices. Culinary students' knowledge of healthy and sustainable nutrition is still scarcely investigated and is limited to the nutritional aspect of the diet, without considering food sustainability or the environmental impact of foods. This study aims to determine the effectiveness of an educational program designed for apprentice chefs. Two questionnaires were administered twice to each student who followed dedicated lectures about nutrition and food sustainability and to other students enrolled as the control group. A total of 264 and 252 apprentice chefs of The School of Italian Culinary Arts-ALMA were enrolled in the control and intervention groups, respectively. At baseline, both groups showed a good level of nutrition knowledge, whereas food sustainability knowledge was lower in all students, regardless of the group. This educational intervention proved to be effective in improving knowledge about nutrition and the environmental impact of food production and consumption. However, a small but significant improvement in nutritional knowledge was also found over time in the control group. Finally, a food sustainability knowledge questionnaire was developed and validated for this study, providing interesting results to be treated as a guide for future developments.

Effect of pre-drying and post-frying holding treatments on the oil absorption and quality of fried batter-coated peanuts.

In this study, the effect of pre-drying and post-frying holding treatments on the oil absorption and the quality of the fried batter-coated peanuts were explored. The results showed that hot air drying and microwave drying induced the gelatinization of starch in the batter before frying. The thermodynamic properties of starch in the batter after frying indicated that pre-drying could protect the orderliness of the starch. CLSM images showed that the pre-drying treatment reduced the number of large oil spots on the surface of batter of fried batter-coated peanuts. SEM observation revealed that the structure of the batter treated with pre-drying was denser and the number of large pores was reduced after frying. The post-frying holding treatment improved the color and texture of the batter-coated peanuts. In conclusion, the pre-drying and post-frying holding treatment can reduce the oil content and improve the fracturability of the fried batter-coated peanuts.

Modern and traditional cooking methods affect the antioxidant activity and phenolic compounds content of Trachystemon Orientalis (L.) G. Don.

Trachystemon orientalis (L.) G. Don is a medicinal plant with beneficial effects on human health. Its antioxidant and phenolic compound content is higher than most natural plants. This is the first study on the cooking of this consumed plant. This study investigated how different cooking methods and times affect the antioxidant activity and phenolic compound content of Trachystemon orientalis (L.) G. Don. The Folin-Ciocalteu method (FCR), ferric-reducing antioxidant power (FRAP), copper-reducing antioxidant capacity (CUPRAC), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were used to evaluate the antioxidant activity and total phenolic content (TPC). Phenolic compounds were also determined by high-performance liquid chromatography (HPLC). Microwave cooking, stir-frying and sous vide increased TPC and antioxidant activity (p<0.05). Steaming decreased TPC and antioxidant activity (p<0.05). It was determined that the best cooking method and time was stir-frying for 15 minutes (TPC, CUPRAC and FRAP values 45.18±3.91 mg GAE/g DW, 15559.39±106.90 mmol Troloks/g DW and 555.10±24.05 µmol Fe (II)/g DW, respectively). Raw Trachystemon orientalis (L.) G. Don was detected with caffeic acid (31.53±0.25 mg/100 g DW). New phenolic compounds (protocatechuic acid and p-coumaric acid) were formed by boiling, stir-frying, microwaving, and sous vide methods. In conclusion, regarding antioxidant activity and phenolic compounds of Trachystemon orientalis (L.) G. Don; the best cooking methods are microwave, stir-frying, and sous vide (p<0.05). The most wrong cooking method is steaming (p<0.05).

Cooking methods determine chemical composition and functional properties of squash blossoms: A study of microstructural and bioaccessibility changes.

This research aimed to evaluate the effect of different cooking methods (boiling, stir-frying, and steaming) on the microstructure, moisture, fat, protein, and glucose-derived carbohydrate contents, and the bioactive compounds (total carotenoids: CAR, total chlorophyll: CHLO, and total phenolic compounds: TPC) and antioxidant capacity (AC) of squash blossoms. Furthermore, we characterized polyphenolic compounds using HPLC and evaluated their bioaccessibility via in vitro digestions. Our results show that steaming and boiling do not affect moisture content. Only stir-frying decreased (p < 0.05) this parameter by 8 %. Additionally, the cooking methods increased (p < 0.05) protein and glucose-derived carbohydrate contents. All cooking methods changed the microstructure of the blossoms, probably due to the thermal and mechanical variations that result in moisture loss and degradation of cell wall components. As for the functional properties, boiling caused a greater loss of TPC (up to 96 %) and AC (up to 91 %). Stir-frying caused the greatest loss of CAR (up to 81 %) and CHLO (up to 84 %). The in vitro digestion assays showed changes in the bioaccessibility of CAR, CHLO, TPC, and AC in the cooked flowers compared to the fresh ones. Finally, kaempferol and gallic acid were the most resistant polyphenols to the cooking methods and in vitro digestion.

Maillard reaction products and metabolite profile of plant-based meat burgers compared with traditional meat burgers and cooking-induced alterations.

We are undergoing a food transformation with the introduction of plant-based meat analogues, but little is known about their chemical characteristics. This study aimed to elucidate the Maillard reactions in plant-based meat burger alternatives (PBMBA). For this purpose, NMR-based metabolomics and targeted MS analysis of Maillard and dehydroalanine pathway markers were conducted on six PBMBA prototypes with different proportions of high-moisture protein extrudates, low-moisture extrudates and pea protein on a commercial PBMBA and on a meat burger before and after cooking. Results revealed that higher levels of Maillard reaction markers were present in PBMBAs in the uncooked state, with lower levels formed during cooking compared with conventional meat. The metabolite profile disclosed that the distinct pattern of the Maillard reaction could be attributed to different substrate availability, but data also revealed that pre-processing of the plant protein affects the presence of Maillard reaction products in PBMBAs.

Improvement of resistant starch content and thermal-stability of starch-linoleic acid complex: An attempt application in extruded recombinant rice.

The utilization of resistant starch in food industry is restricted due to its susceptibility to thermal degradation. This work aimed to address this issue by preparing a starch-linoleic acid complex (RS5) via extrusion method combined with heat moisture treatment, obtaining VII-type crystal (melting temperature âˆ¼110 °C). The complex obtained through an 8-hour heat moisture treatment exhibited a high RS content of 46.7 %. The glycemic index (pGI) values predicted by two different methods for this complex were 54.5 and 64.2. The complex was further processed into recombinant rice, which exhibited similar textural properties to commercial rice products after cooking. Notably, the recombinant rice maintained an anti-enzyme structure (VII-type complex) as evidenced by its significant resistant starch content of 38.1 %, the lowest pGI values of 59.6 and 72.5. These findings could serve as a useful reference to aid in developing low glycemic index foods based on starch.

A comprehensive study of sous-vide cooked Korat chicken breast processed by various conditions: texture, compositional/structural changes, and consumer acceptance.

Korat chicken (KC) is a slow-growing crossbreed renowned for its excellent growth and firm texture. This study investigated the effect of various sous-vide (SV) conditions (60 and 70°C, 1-3 h) on their texture, protein structure and degradation, as well as consumer acceptability, with the traditional boiling served as control. Texture showed significant improvement under all SV conditions compared to the control, as demonstrated by increased water holding capacity (WHC), cooking loss, and decreased shear force, hardness, and chewiness (P < 0.05). These changes corresponded to the higher sensory scores (P < 0.05). Among the SV samples, increased temperatures and longer cooking times led to higher degradation of myofibrils and connective tissue, as evidenced by a decrease in water-, salt-soluble proteins, and soluble collagen (P < 0.05). These findings aligned with the scanning electron microscopy (SEM) results, which showed a looser muscle structure in the meat under more intense cooking conditions. Based on synchrotron radiation-based Fourier transform infrared (SR-FTIR) results, a gradual increase in antiparallel forms within the amide I bands (1,700-1,600 cm-1) of the total spectra with higher temperature and longer cooking times was observed (P < 0.05), while the fluctuations were observed in the changes of α-helix, ß-sheet, and ß-turn structures. This suggested that the antiparallel structure represented a looser configuration developing during intense SV cooking. Combined with the principal component analysis (PCA) results, the findings indicated that the suitable SV condition for KC breast meat was 70°C for varying durations (1-3 h), as it showed the strongest correlation with sensory scores, particularly in terms of tenderness. In summary, these findings provided a better understanding of molecular changes and discovered SV conditions to enhance the texture quality of the KC meat.

Study by means of 1H nuclear magnetic resonance of the oxidation process in high oleic sunflower oil and palm oil during deep-frying of fish cakes.

This study aimed to compare the frying performance of palm oil (PO) and high oleic sunflower oil (HOSO) during frying aquatic products. The quality change and frying performance of HOSO and PO during frying of fish cakes were investigated. The oxidation and hydrolysis products of both oils were explored by the nuclear magnetic resonance technique. The results showed that the color deepening rate of PO was higher than that of HOSO. After 18 h of frying, the total polar compound content of PO and HOSO reached 25.67% and 27.50%, respectively. HOSO had lower degree of oxidation than PO after 24 h of continuous frying. The polyunsaturated fatty acid content in HOSO and PO significantly decreased. The oleic acid content in HOSO remained above 80% during the frying process. The major aldehydes in both oils were (E, E)-2,4-alkadienals and n-alkanals and glycerol diesters (DAGs) were abundant in PO. Furthermore, the addition of fish cakes had slight effect on the quality of the frying oil. Therefore, HOSO is an appropriate candidate for frying owing to its excellent frying stability and nutritional value.

Effects of extrusion screw speed, feed moisture content, and barrel temperature on the physical, techno-functional, and microstructural quality of texturized lentil protein.

Utilizing lentil protein as a novel ingredient for producing texturized vegetable proteins (TVPs) can provide new opportunities for the production of next-generation hybrid meat products. TVPs from lentil protein isolate were manufactured using low-moisture extrusion cooking at different combinations of screw speed (SS), feed moisture content (MC), and barrel temperature (BT) profile. In total, seven different combinations of processing treatments were tested, and the resulting TVPs were characterized for their physical (rehydration ratio, texture profile analysis, color, and bulk density), techno-functional (oil and water holding capacities), and microstructural properties. The processing conditions of higher SS and lower MC resulted in increased values of several textural profile attributes (springiness, cohesiveness, and resilience), increased water holding capacity (WHC), and decreased bulk density. Compared to raw lentil protein, TVPs showed enhanced oil holding capacity, though WHC either decreased or remained constant. The extrusion response parameters (die pressure, torque, and specific mechanical energy) showed positive correlations with several physical properties (texture, WHC, and total color change), revealing their potential for serving as important TVP quality indicators. TVPs produced at SS, MC, and BT of 450 rpm, 30%, and 140°C, respectively, showed relatively better overall physical and techno-functional quality and can be used as meat extenders in hybrid meat patties. Overall, this research evidenced the viability of lentil protein as a potential ingredient for producing low-moisture TVPs.

Barriers and facilitators to consuming pulses: a qualitative exploration including effects of trying recipes at home.

Pulses are a healthy, sustainable, low cost food, but consumption levels are low for a variety of reasons, including practical and cooking concerns. This work aimed to explore barriers and facilitators towards pulse consumption and increasing consumption, and the potential value of cooking suggestions and recipes for changing these perceptions. Two qualitative studies were undertaken. In Study 1, 21 participants (10 males, 11 females, of a range of ages, cooking responsibilities, and experiences with pulses) were interviewed both before and after receiving cooking suggestions and recipes. In Study 2, 12 participants (2 males, 10 females, as above) were interviewed once after trying recipes. Interviews were audio-recorded, transcribed, and analysed using thematic analysis. Seven themes described barriers and facilitators towards pulse consumption: 'Enjoyment and Sensory properties'; 'Benefits and Recommendations'; 'Practical Concerns'; 'Cooking Concerns'; 'Compatibility with current diet'; 'Personal Influences'; and 'External Influences'. Some similar themes also referred to increasing consumption: 'Willingness'; 'Awareness, Knowledge of Benefits'; 'Knowledge of Cooking and Practical Concerns'; and 'Compatibility with current diet'. Cooking suggestions and recipe use resulted in themes on 'Awareness'; 'Willingness, Trying New Things'; 'Small Changes'; and facilitators associated with 'Enjoyment, Sensory Properties, Practical Concerns, Benefits' and 'Knowledge, Cooking Ideas and Confidence, Incorporation, Cooking Solutions'. Barriers related to 'Risk and Preconceptions'; 'Awareness, but' inaction and additional considerations were also found. Our findings demonstrate a positive role for pulse consumption for increased experience, familiarity, and confidence with preparing, cooking, and consuming these healthy and sustainable foods.

Human gut microbiota fermentation of cooked eggplant, garlic, and onion supports distinct microbial communities.

Heating and cooking vegetables not only enhances their palatability but also modifies their chemical structure, which in turn might affect their fermentation by resident gut microbes. Three commonly consumed vegetables that are known to undergo chemical browning, also known as Maillard reaction, during cooking - eggplant, garlic, and onion - were each fried, grilled, or roasted. The cooked vegetables were then subjected to an in vitro digestion-fermentation process aimed to simulate the passage of food through the human oro-gastro-intestinal tract. In the last step, the undigested fractions of these foods were anaerobically fermented by the complex human gut microbiota. We assessed the structure of microbial communities maintained on each cooked vegetable by high-throughput 16S rRNA gene amplicon sequencing, measured the levels of furosine, a chemical marker of the Maillard browning reaction, by HPLC, and determined the antioxidant capacities in all samples with ABTS and FRAP methods. Overall, vegetable type had the largest, statistically significant, effect on the microbiota structure followed by the cooking method. Onion fermentation supported a more beneficial community including an expansion of Bifidobacterium members and inhibition of Enterobacteriaceae. Fermentation of cooked garlic promoted Faecalibacterium growth. Among cooking methods, roasting led to a much higher ratio of beneficial-to-detrimental microbes in comparison with grilling and frying, possibly due to the exclusion of any cooking oil in the cooking process.