Food Microbiology Commons^™

Biological Strategies And Mathematical Approaches For Limiting Bacterial Contaminants And Chemical Pollutants In Bioethanol Fermentations, Alia Chahed Ep Limayem

Graduate Theses and Dissertations

During the most recent decades increased interest in fuel from biomass in the United States and worldwide has emerged each time petroleum derived-gasoline registered well publicized spikes in price. The willingness of the U.S. government to face the issues of more heavily high-priced foreign oil and climate change has led to more investment on plant-derived sustainable biofuel sources. Biomass derived from corn has become one of the primary feedstocks for bioethanol production for the past several years in the U.S. However, the argument of whether to use food as biofuel has led to a search for alternative non-food sources. Consequently, …

Response Surface Methodology Approach For The Optimization Of Lab Fermentation Using Vegetable Based Substrate, Amit Jaiswal, Nissreen Abu-Ghannam, Juan Valverde

Conference papers

In the present studies, an attempt was made to optimize the conditions for the lactic acid bacteria (LAB) fermentation using Irish York cabbage (Brassica oleracea var. capitata alba subvar. conica) as a substrate. Prior to fermentation with Lactobacillus plantarum, York cabbage was blanched at 95°C for 12 min to inactivate surface microflora. To achieve an optimal fermentation condition which would result in higher release of phytochemicals and antioxidant capacity in the broth, Box-Behnken design integrating a desirability approach was used. The optimized factors (fermentation time 36h, solid/liquid ratio 0.25 g/ml and agitation rate 100 rpm) were used for …

Delicious-Ology: The Science Of Delicious Food, Sasha Yan

Undergraduate Theses—Unrestricted

You can read this book two ways. If you want to “just cook,” flip to the recipe index, pick a recipe, and skip straight to that page. The surrounding text will explain some aspects of the science behind the recipe. While the recipes in this book are chosen to complement and provide examples of the science, they’re also recipes that are fantastic in and of themselves.

Detection And Identification Of Salmonella Enterica, Escherichia Coli, And Shigella Spp. Via Pcr-Esi-Ms: Isolate Testing And Analysis Of Food Samples, Sarah E. Pierce, Rosalee S. Hellberg, Chorng-Ming Cheng, Kai-Shun Chen, Donna M. Williams-Hill, William B. Martin, Marc W. Allard

Food Science Faculty Articles and Research

An assay to identify the common food-borne pathogens Salmonella, Escherichia coli, Shigella, and Listeria monocytogenes was developed in collaboration with Ibis Biosciences (a division of Abbott Molecular) for the Plex-ID biosensor system, a platform that uses electrospray ionization mass spectroscopy (ESI-MS) to detect the base composition of short PCR amplicons. The new food-borne pathogen (FBP) plate has been experimentally designed using four gene segments for a total of eight amplicon targets. Initial work built a DNA base count database that contains more than 140 Salmonella enterica, 139 E. coli, 11 Shigella, and 36 Listeria patterns and 18 other Enterobacteriaceae organisms. …

Antimicrobial Efficacy Of Edible Soy Protein Isolate Films And Coatings Incorporated With Hop Ethanol Extract And The Influence On Shelf-Life And Sensory Attributes Of Bologna, Jamie R. G. Skudlarek

Theses and Dissertations--Animal and Food Sciences

There is demand for improved security of refrigerated ready-to-eat meats. Antimicrobial edible films and coatings could function as an added barrier against post-processing contamination. Hops and hop extracts are known for their antimicrobial efficacy which is attributed to key antimicrobial components including humulones, lupulones, xanthohumol and various terpenoids. Yet, hop ethanol extract has not been studied as an antimicrobial to incorporate into edible protein films and/or coatings. The overall objective of this research was to evaluate hop ethanol extract as an antimicrobial agent incorporated into edible soy protein isolate (SPI) films and coatings, and the influence on the shelf-life and …

Recent Advances In The Application Of Non Thermal Methods For The Prevention Of Salmonella In Foods, Shilpi Gupta, Nissreen Abu-Ghannam

Books/Book Chapters/ Proceedings

Food-borne illness as a result of consumption of foods contaminated with pathogenic bacteria is a world-wide concern. The presence and subsequent growth of micro-organisms in food in addition to improper storage not only results in spoilage but also in a reduction of food quality. The microbiological safety in ready to eat products is a cause of big concern not only for the consumers and food industries but also for the regulatory agencies. The number of documented outbreaks of foodborne diseases has increased in the last decade with Salmonella spp., Listeria monocytogenes and Escherichia coli being responsible for the largest number …

Optimization Of Lactic Acid Fermentation Of York Cabbage For The Development Of Potential Probiotic Products, Amit Jaiswal, Shilpi Gupta, Nissreen Abu-Ghannam

Articles

In the present study, York cabbage was used as the sole substrate for the lactic acid (LA) fermentation with Lactobacillus plantarum. York cabbage was blanched at 95°C for 12min to inactivate surface microflora prior to fermentation. To achieve an optimal fermentation condition which would result in higher release of phytochemicals and antioxidant (AO) capacity in the broth, Box-Behnken design integrating a desirability approach was used. A second-order polynomial equation was developed indicating the effect of solute/liquid ratio, agitation rate and fermentation time on desired parameters. The optimized factors were used for fermenting York cabbage to obtain maximum bacterial growth, …

Antimicrobial, Antioxidant And Free Radical-Scavenging Capacity Of Brown Seaweed Himanthalia Elongata From Western Coast Of Ireland, Gaurav Rajauria, Amit Jaiswal, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Water,methanol and mixtures (20–80%) thereof have been used for the extraction of phenolic compounds from Irish brown seaweed Himanthalia elongata for studying its antimicrobial and antioxidant properties.The 60%methanolic extract exhibited significantly (P < 0.05) the highest value of yield (6.8 6 0.24%), total phenol (286.0 6 4.61 mg gallic acid equivalents/g), flavonoid (109.8 6 2.68 mg quercetin equivalents/g) and condensed tannin content (35.6 6 1.03 mgcatechin equivalents/ g). Antimicrobial activity of 60% methanolic extract tested from disc diffusion and broth dilution methods was effective against various food spoilage and pathogenic bacteria studied.The same extract exhibited statistically highest reducing power and antioxidant capacity againstDPPHradical,metal ions, lipid peroxides and hydrogen peroxide radicals. The UV-visible spectroscopy showed absorption maxima at 205 and 260 nm and the presence of hydroxyl group (3,431 cm-1) and an aromatic ring (around 1,465, 1,505 and 1,624 cm-1) in Fourier Transform Infrared spectroscopy, suggested the presence of phenolic compounds in the extract.

Evaluation Of Novel Low Molecular Weight Antimicrobial Compounds Produced By Lactic Acid Bacteria., Jiahui Leona Guo

Theses

Fungal food spoilage plays a pivotal role in the deterioration of food and feed systems and some fungi are also able to produce compounds toxic for humans and animals. The mycotoxins produced by fungi can cause serious health hazards and include toxins which are cancerogenic, immunotoxic, teratogenic, neurotoxic, nephrotoxic or hepatotoxic effects and Kashin-Beck disease. In addition to this, fungal spoilage/pathogens cause losses of marketable quality and hygiene of foodstuffs, resulting in major economic problem throughout the world. Nowadays, food spoilage can be prevented using physical and chemical methods, but no efficient strategy has been proposed so far to reduce …

Studies On The Adherence Properties Of Plant Lectins And Bacterial Adhesins And Their Inhibition By Prebiotic Oligosaccharides And Bovine Colostrum Fractions, Maria X. Maldonado-Gomez

Department of Food Science and Technology: Dissertations, Theses, and Student Research

To initiate colonization and infection, most microbial pathogens must first recognize and adhere to cells in the host tissues. Adherence inhibition, therefore, can be used as a strategy for preventing infectious disease. In this research, we developed a simplified model using plant lectins and HEp-2 tissue culture cells to simulate bacterial adhesins-receptors interactions. The effect of lectin ligands and two prebiotic carbohydrates, galactooligosaccharide (GOS) and polydextrose (PDX) was measured with this approach. Lectins that were able to bind to the target cells were inhibited in the presence of the cognate ligands and at least one of the prebiotic carbohydrates. The …

Effect Of Sodium Nitrite, Sodium Erythorbate And Organic Acid Salts On Germination And Outgrowth Of Clostridium Perfringens Spores In Ham During Abusive Cooling, Mauricio A. Redondo

Department of Food Science and Technology: Dissertations, Theses, and Student Research

The effect of sodium nitrite (NaNO₂), sodium erythorbate, sodium chloride (NaCl) and organic acid salts (potassium lactate and sodium diacetate) on C. perfringens spore germination and outgrowth in ham was evaluated. The research was divided in two parts. The first experiment consisted of potential C. perfringens spore germination and outgrowth in ham containing combinations of NaNO₂ (0, 50, 100, 150 or 200 ppm) and sodium erythorbate (0 or 557 ppm) during cooling. This experiment included the evaluation of residual nitrite levels as affected by temperature (heat shock at 75°C for 20 min and subsequent cooling from 54.4°C …

Investigation Of In-Package Ozonation: The Effectiveness Of Ozone To Inactive Salmonella Enteritidis On Raw, Shell Eggs, Austin Donner

The Journal of Purdue Undergraduate Research

Food production, handling, and distribution practices pose a constant threat to the quality and safety of food products. The objective of this research is to evaluate an innovative in-package ozonation process to reduce Salmonella enteritidis on raw, shell eggs. Previous research has shown that in-package ozonation eliminates contaminants from outside sources, reduces pathogens, and extends shelf life. In this study, raw, shell eggs were inoculated with Salmonella enteritidis and exposed to ozonation treatment. Microbial recoveries were then tested to determine bacterial reductions. Measurements included: relative humidity (34 percent at 5^oC), surface temperatures (^oC), ozone concentrations, bacterial …

Emerging Dynamics Of Human Campylobacteriosis In Southern Ireland, Susan Bullman, Daniel Corcoran, James O'Leary, Derry O'Hare, Brigid Lucey, Roy D. Sleator

Department of Biological Sciences Publications

Infections with Campylobacter spp. pose a significant health burden worldwide. The significance of Campylobacter jejuni/Campylobacter coli infection is well appreciated but the contribution of non-C. jejuni/C. coli spp. to human gastroenteritis is largely unknown. In this study, we employed a two-tiered molecular study on 7194 patient faecal samples received by the Microbiology Department in Cork University Hospital during 2009. The first step, using EntericBio® (Serosep), a multiplex PCR system, detected Campylobacter to the genus level. The second step, utilizing Campylobacter species-specific PCR identified to the species level. A total of 340 samples were confirmed as Campylobacter genus positive, 329 of …

Hyperspectral Imaging For The Detection Of Microbial Spoilage Of Mushrooms, Edurne Gaston, Jesus Maria Frias, Patrick Cullen, Colm O’Donnell, Aoife Gowen

Conference papers

Brown blotch, caused by pathogenic Pseudomonas tolaasii, is the most problematic bacterial disease in Agaricus bisporus mushrooms; it reduces their consumer appeal in the market place, thus generating important economical losses worldwide. The mushroom industry is in need of fast and accurate evaluation methodologies to ensure that only high quality produce reaches the market. Hyperspectral imaging (HSI) is a non-destructive technique that combines imaging and spectroscopy to obtain spatial and spectral information from an object. The aim of this study was to investigate the potential of Vis-NIR HSI to identify microbiological damage in mushrooms and to discriminate it from …

The Antimicrobial Activity Of Cold Pressed Terpeneless Valencia Orange Oil At Cold Temperatures, Sean Jeffrey Pendleton

Graduate Theses and Dissertations

This research was undertaken to identify an antimicrobial for use during chilling in beef processing, including periods of temperature abuse, as well as to evaluate membrane filtration as means to remove essential oils from bacteria to prevent further antibacterial action. Cold pressed terpeneless Valencia orange oil was examined in combination with various temperatures (37°C, 10°C, and 4°C) to determine its antimicrobial activity against various strains of bacteria. The strains were tested using a ninety-six well microtiter plate method, with or without membrane filtration. The compound 2, 3, 5-triphenyl tetrazolium chloride was used as a growth indicator. Serial, two fold dilutions …

Analysis Of Rice Blast Resistance Genes In The National Small Grains Collection (Nsgc), Moytri Roychowdhury

Graduate Theses and Dissertations

Identification of blast resistance genes in rice germplasm is one of the most important activities of rice breeding programs in worldwide. The objective of this research was to characterize two major blast resistance genes, Pi-z and Pi-b, in selected rice germplasm. A simple sequence repeat DNA marker, AP5659-1 linked to the Pi-z gene, and a Pib dominant marker derived from the Pi-b gene were first used to screen a rice core collection consisting of 1700 accessions estimated to represent 70% of the genetic diversity of rice in the US National Small Grains Collection. There were 131 rice germplasm accessions with …

Microbiological, Thermal Inactivation, And Sensory Characteristics Of Beef Eye-Of-Round Subprimals And Steaks Processed With High-Pressure Needleless Injection, Laura Kahealani Jefferies

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

High-pressure needleless injection (HPNI) is a process where small-diameter, high-velocity burst of liquid, penetrate foods at pressures ≤ 10,000 psi. The potential of HPNI as an enhancing technique for meat was studied. In study 1, HPNI translocated surface E. coli O157 into the interior of beef eye-of-round subprimals with an incidence of 40 (±7), 25 (±8), and 25 (±8)% for meat that had been surface-inoculated with a four-strain cocktail at 0.5, 1, and 2 log₁₀ CFU/cm², respectively. Run-off water contained 2, 2, and 3 log₁₀ CFU/ml and was used for HPNI of additional subprimals, which resulted …

Optimisation Of Accelerated Solvent Extraction Of Antioxidant Compounds From Rosemary (Rosmarinus Officinalis L.), Marjoram (Origanum Majorana L.) And Oregano (Origanum Vulgare L.) Using Response Surface Methodology, M. Hossain, Catherine Barry-Ryan, Ana Belen Martin-Diana, N. Brunton

Articles

The present study optimised the accelerated solvent extraction (ASE) conditions (Dionex ASE® 200, USA) to maximise the antioxidant capacity of the extracts from three spices of Lamiaceae family; rosemary, oregano and marjoram. Optimised conditions with regard to extraction temperature (66–129 °C) and solvent concentration (32–88% methanol) were identified using response surface methodology (RSM). For all three spices results showed that 129 °C was the optimum temperature in order to obtain extracts with high antioxidant activity. Optimal methanol concentrations with respect to the antioxidant activity of rosemary and marjoram extracts were 56% and 57% respectively. Oregano showed a different response to …

Quantitative Assessment Of The Shelf-Life Of Ozonated Apple Juice, Sonal Patil, Vasilis Valdramidis, Brijesh Tiwari, Patrick J. Cullen, Paula Bourke

Articles

Sterile apple juice inoculated with S. cerevisiae ATCC 9763 (10³ CFU/mL) was processed in a bubble column with gaseous ozone of flow rate of 0.12 L/min and concentration of 33-40 µg/mL for 8 min. The growth kinetics of S. cerevisiae as an indicator of juice spoilage was monitored at 4, 8, 12 and 16 ºC for up to 30 days. The kinetics were quantitatively described by the primary model of Baranyi and Robert’s and the maximum specific growth rate was further modeled as a function of temperature by the Ratkowsky type model. The developed model was successfully validated for …

Storage Effects Of Gel Encapsulation On Stability Of Chokeberry Monomeric Anthocyanins, Procyanidins, Color Density, And Percent Polymeric Color, Mary Kordsmeier, Luke Howard

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Chokeberries (Aronia melanocarpa) are an antioxidant-rich plant product due to their high content of polyphenols, especially anthocyanins and procyanidins. These polyphenols have been shown to provide protection against coronary heart disease, stroke, and lung cancer, as well as against oxidative stress, the main cause behind chronic diseases promoted by free radicals. The objective of this study was to determine the storage effects of gelatin encapsulation on monomeric anthocyanins, procyanidins, color density, and percent polymeric color of three gummy candies of different strengths formulated with a base of 25.4% chokeberry concentrate, 47.6% sucrose, 1.3% Splenda, and 0.025% potassium sorbate. The gum …

Effect Of Processing Conditions On Phytochemical Constituents Of Edible Irish Seaweed Himanthalia Elongata., Sabrina Cox, Nissreen Abu-Ghannam, Shilpi Gupta

Articles

Seaweed iswell recognized as an excellent source of phytochemicals. This study was a preliminary screening to investigate the effects of various food processing methods on the phytochemicals of Himanthalia elongata. Hydrothermal processing was carried out until an edible texture was achieved. The total phenolic content (TPC) of fresh H. elongata was 175.27 mg gallic acid equivalent (GAE)/100 g fresh weight (FW) while boiling significantly reduced the TPC to 25.4 mg GAE/100 g FW
(P < 0.05).A drying pretreatment before boiling reduced the cooking time therefore leading to less leaching of antioxidants upon boiling. In terms of extract, drying of H. elongata followed by boiling had the most significant effect on the phytochemicals as TPC increased by 174%. Boiled extracts had the most effective 2, 2-diphenyl- 1-picrylhydrazyl scavenging activity (EC50 of 12.5 mg/mL). As a comparison, seaweed subjected to the same treatments was studied in terms of antimicrobial activity.Overall, extracts fromfresh H. elongata achieved the highest inhibition.

The Effect Of Untreated And Enzyme-Treated Commercial Dairy Powders On The Growth And Adhesion Of Streptococcus Mutans, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan

Articles

Dental caries is a common bacterial infection, but the progression of this disease can be delayed by preventing initial attachment of cariogenic bacteria such as Streptococcus mutans to tooth surfaces. This study firstly compares the effect of untreated (UT) and enzyme-treated (ET) dairy powders on the adherence of S. mutans to hydroxylapatite (HA), an analogue of tooth enamel. A fluorescence-based method was used to quantify adherence of S. mutans to HA both in the presence (S-HA) and absence (PBS-HA) of saliva. Secondly, binding of proteins present in the test materials to HA was quantified using bicinchonic acid assays and SDS-PAGE. …

Properties Of Gluten-Free Pasta Prepared From Rice And Different Starches, Alexandria W. Mertz, Ya-Jane Wang

Discovery, The Student Journal of Dale Bumpers College of Agricultural, Food and Life Sciences

Rice is one of the few cereal products that does not contain gluten. However, the absence of gluten poses problems in the structure of and cooking quality of rice pasta. The objective of this project was to investigate the addition of starch on the physicochemical properties and cooking quality of rice-based pasta. Rice-based pasta was prepared from parboiled long-grain rice flour with the addition of 25% cooked starch from different sources. The color and pasting properties of the ground pasta flour were measured by a chroma meter and a Rapid Visco Analyser, respectively. The pasta was cooked to the optimum …

Evaluation Of Natural Antimicrobial Phenolic Compounds Against Foodborne Pathogens, Hayriye Cetin-Karaca

University of Kentucky Master's Theses

Raw and processed foods are vulnerable to contamination during their production, distribution and sale. Thus, a wide variety of chemical preservatives are used in the food industry to prevent the growth of food spoilage and pathogenic bacteria. However, health and economic concerns have led to an intensive search for natural alternatives, such as plant extracts, that can safely be used as substitutes for synthetic antimicrobials and preservatives to partially or completely inhibit the growth of bacteria.

This study evaluated the antimicrobial effects of natural phenolic compounds extracted from vegetables, fruits, herbs and spices. The main objective was to determine the …

Application Of Principal Component And Hierarchical Cluster Analysis To Classify Different Spices Based On In Vitro Antioxidant Activity And Individual Polyphenolic Antioxidant Compounds, M. Hossain, A. Patras, Catherine Barry-Ryan, Ana Belen Martin-Diana, N. Brunton

Articles

This study investigated the variations in antioxidant profiles between spices using pattern recognition tools; classification was achieved based on the results of global antioxidant activity assays (2,2-diphenyl-1-picrylhydrazyl [DPPH], oxygen radical absorbance capacity [ORAC], ferric reducing antioxidant power [FRAP], microsomal lipid peroxidation [MLP] and 2,2′-azinobis(3-ethylbenzothiazoline-6-sulfonic acid) [ABTS]), levels of different polyphenolic compounds (gallic acid [GA], carnosol [CAR], carnosic acid [CRA], caffeic acid [CA], rosmarinic acid [RA], luteolin-7-O-glucoside [LOG], apigenin-7-O-glucoside [APOG] and total phenols [TP]) of spices namely rosemary, oregano, marjoram, sage, basil, thyme, fennel, celery, cumin and parsley, commonly consumed in Ireland were analyzed. Rosemary showed the highest antioxidant activity measured …

Determination Of The Effect Of Dairy Powders On Adherence Of Streptococcus Sobrinus And Streptococcus Salivarius To Hydroxylapatite And Growth Of These Bacteria, Rachel Halpin, D.B. Brady, E.D. O’Riordan, M. O’Sullivan

Articles

Dental caries is a highly prevalent disease caused by colonisation of tooth surfaces by cariogenic bacteria, such as Streptococcus sobrinus and Streptococcus salivarius. Reducing initial adherence of such bacteria to teeth may delay onset of caries. Many foods, such as milk, can inhibit microbial adherence. In this investigation, the effect of untreated (UT) and enzyme-treated (ET) dairy powders on adherence of S. sobrinus and S. salivarius to hydroxylapatite (HA), an analogue of tooth enamel, was examined. Untreated (UT) acid whey protein concentrate (AWPC) 80 inhibited streptococcal adherence to phosphate-buffered saline-coated HA (PBS-HA) and saliva-coated HA (S-HA) by >80% at …

Growth Inhibition Of Common Food Spoilage And Pathogenic Microorganisms In The Presence Of Brown Seaweed Extracts, Shilpi Gupta, Sabrina Cox, Gaurav Rajauria, Amit Jaiswal, Nissreen Abu-Ghannam

Articles

The possibility of using extracts from brown seaweed, Himanthalia elongata, as a natural antimicrobial agent for food preservation is presented. The effect of different concentrations of seaweed extract on the growth kinetics of four common food spoilage (Pseudomonas aeruginosa and Enterococcus faecalis) and food pathogenic micro-organisms (Listeria monocytogenes and Salmonella abony) was examined. Seaweed extract at a concentration of 6% inhibited the growth of all four of the studied organisms. Lower concentrations of seaweed extract prolonged the lag phase and reduced both the exponential growth rate and final population densities of the culture. Suitability of three kinetic models, Baranyi-Roberts, Modified …

The Bifidogenicity Of The Prebiotic Galactooligosaccharides, Lauren M. G. Davis

Department of Food Science and Technology: Dissertations, Theses, and Student Research

The goal of this research was to determine the effect of different doses of galactooligosaccharide (GOS) on the fecal microbiota of healthy adults, with a focus on bifidobacteria. The study was designed as a single-blinded study, with eighteen subjects consuming GOS-containing chocolate chews at four increasing dosage levels; 0, 2.5, 5.0, and 10.0 g. Subjects consumed each dose for 3 weeks, with a two-week baseline period preceding the study and a two-week washout period at the end. Cultural methods were used for bifidobacteria, Bacteroides, enterobacteria, enterococci, lactobacilli, and total anaerobes; culture-independent methods included denaturing gradient gel electrophoresis (DGGE) and …

Identification And Characterization Of Salmonella Serotypes Isolated From Pork And Poultry From Commercial Sources, Yulie Edith Meneses-GonzáLez

Department of Food Science and Technology: Dissertations, Theses, and Student Research

Salmonella is one of the leading causes of foodborne illness worldwide, and it is estimated that 1.4 million infections occur annually in the U.S. alone. The Premi®Test Salmonella (PTS), is a potential tool for rapid detection and identification of Salmonella serovars. The objective of this project was to evaluate the use of the PTS system as a serotyping tool to identify pork and poultry isolates obtained from vertically integrated operations and to characterize their antibiotic resistance. Two hundred isolates were evaluated. All isolates were serotyped using the traditional Kaufmann-White scheme and the PTS system. Among the isolates 63 different serotypes …

Metabolic Profiling And Fingerprinting For The Detection And Discrimination Of Mechanical Damage In Mushrooms (Agaricus Bisporus) During Storage, Aoife O'Gorman

Doctoral

Horticultural products such as mushrooms are exposed to external agents during their postharvest life, which are going to affect product quality. Loss of whiteness during storage is particularly important in the mushroom industry. Rough handling and distribution of crops, fruiting body senescence, bacterial and viral infection are among the causes of mushroom discolouration. The aim of this work was to study the use of metabolic fingerprinting and metabolic profiling tools for the detection and discrimination of mechanical damage on mushrooms. This research involved: 1. Investigating whether the chemical changes induced by mechanical damage and ageing of mushrooms could be (a) …