Biofilm Formation and Removal
Cleaning and Safety in the Food Industry
Lynne McLandsborough is a highly respected food microbiologist who has made significant contributions in the study of food safety including biofilm formation of pathogenic and spoilage organisms in the food processing environment and how to remove them. One of her major accomplishments is the development of antimicrobial delivery systems, and she is currently working on developing non-water-based cleaning and sanitation systems for use in the food industry.
University of Minnesota: Ph.D., Food Science
University of Minnesota: M.S., Food Science
Miami University (Ohio): B.A., Microbiology
Select Media Coverage (3)
Fact Check: Chicken Is NOT 'Poison'
Lead Stories online
Lead Stories reached out to Lynne McLandsborough, head of the department of food science at the University of Massachusetts Amherst in Amherst, Massachusetts, for comment on the claim. She responded in a January 18, 2023, email: Chicken is not poisonous. It is a protein-rich food that is rich in B vitamins needed for the human diet.
Fact Check: Parmesan Cheese Flavor Additive Is NOT Toxic In Small Amounts
Lead Stories online
Lynne McLandsborough provided similar but slightly different insights about the claim in a January 9, 2023, email. She wrote that butyric acid is "expected" in the human body and that it forms in the colon when dietary fiber is consumed. The acid, in fact, acts as "an energy source" for "cells surrounding the colon" and, she added, "has been shown to have anti-inflammatory properties in the colon."
Is oil the secret to stopping Salmonella?
New Food Magazine online
“Cleaning and sanitation of manufacturing environments are critical for a safe food supply,” said lead author Lynne McLandsborough, a professor of food science at University of Massachusetts Amherst. However, water-based cleaning is rarely used in processing peanut butter, because it promotes microbial growth.
Select Publications (5)
Exploring Washing Procedures for Produce Brush WasherJournal of Food Protection
2023 Previous environmental monitoring projects in food production facilities have revealed inconsistencies in how produce brush washer machines are cleaned after use; thus, study of effective sanitation procedures for these machines is needed. Four chlorine solution treatments (ranging from 25-200ppm), as well as a water-only treatment, were tested for efficacy in reducing bacterial loads for a selected small brush washer machine. Results indicate that rinsing with the machine's power and water alone, a frequent practice among some produce processors, yielded a reduction of 0.91-1.96 log CFU per brush roller in bacterial counts, which was not statistically significant (p>0.05). However, the chlorine treatments were found to be effective in reducing bacterial loads significantly, with higher concentrations being the most effective.
Efficacy of acidified water-in-oil emulsions against desiccated Salmonella as a function of acid carbon chain-length and membrane viscosityFrontiers in Microbiology
2023 Sanitizing low-moisture food (LMF) processing equipment is challenging due to the increased heat resistance of Salmonella spp. in low-water activity (a w ) environments. Food-grade oils mixed with acetic acid have been shown effective against desiccated Salmonella . In this study, different hydrocarbon chain-length (C n ) organic acids were tested against desiccated Salmonella by using 1% v/v water-in-oil (W/O) emulsion as the delivery system for 200 mM acid. Fluorescence lifetime imaging microscopy (FLIM) was utilized with a BODIPY-based molecular rotor to evaluate membrane viscosity under environmental conditions such as desiccation and temperature elevation. Drying hydrated Salmonella cells to 75% equilibrium relative humidity (ERH) increased the membrane viscosity from 1,199 to 1,309 mPa·s (cP) at 22°C.
Oil-Based Sanitization in Low-Moisture Environments: Delivery of Acetic Acid with Water-in-Oil EmulsionsMicrobiology Spectrum
2023 Contamination with Salmonella spp. and Listeria monocytogenes is concerning across low-moisture food (LMF)-processing environments due to the pronounced survival of these organisms under dry conditions. This study treated desiccated bacteria with acetic acid delivered by oil with and without water-in-oil (W/O) emulsion. The influences of cellular desiccation, emulsion water concentration, water activity (aw), and treatment temperature were investigated. Acetic acid dissolved in oil (i.e., acidified oil) showed low levels of antimicrobial efficacy. After treatment with acidified oil (200 mM acetic acid at 22°C for 30 min), Salmonella enterica serovar Enteritidis phage type 30 cells desiccated to 75% equilibrium relative humidity (ERH) and 33% ERH were reduced by 0.69 and 0.05 log CFU/coupon, respectively. The dispersion of a low level of water (≥0.3%, vol/vol) within the acidified oil with the surfactant (i.e., acidified W/O emulsion) significantly enhanced the antimicrobial efficacy.
Synergistic photoinactivation of Escherichia coli and Listeria innocua by curcumin and lauric arginate ethyl ester micellesLWT
2022 This study evaluated the changes in dispersibility in the aqueous phase, chemical stability, and antimicrobial activity of curcumin after being encapsulated in a lauric arginate ethyl ester (LAE) micelle. Stock curcumin-LAE solutions were prepared by titrating curcumin dissolved in ethanol into LAE aqueous solutions (pH 3.5). The LAE in the stock solutions inhibited the crystallization and prevented the chemical degradation of curcumin during storage at 20 °C. The antimicrobial activity of the curcumin-LAE solutions against Escherichia coli (E. coli) and Listeria innocua (L. innocua) cocktails was assessed by exposing the sample to UV-A light (λ = 365 nm) for 5 min. For samples with both LAE and curcumin at pH 3.5 during irradiation, synergistic antimicrobial activity was observed. The release of protein or nucleic acid from the cells indicated an increase in its membrane permeability after treatments which was due to LAE-facilitated interaction between the photosensitizer and the membrane.
Efficacy of Acidified Oils against Salmonella in Low-Moisture EnvironmentsApplied and Environmental Microbiology
2022 When processing low-moisture, high-fat foods such as peanut butter and nuts, water-based sanitization is unsuitable due to the immiscible nature of water and fats. Dry sanitization mainly uses flammable compounds such as isopropanol, requiring equipment cooling before application. The use of oils to deliver antimicrobials against foodborne pathogens enables the use of elevated temperatures, thus eliminating processing downtimes associated with dry sanitization. This study delivered organic acids and medium-chain fatty acids (100, 250, and 500 mM) in peanut oil against Salmonella enterica serovar Enteritidis desiccated at 75% relative humidity (RH). Acetic acid in peanut oil (AO) at 45°C was the most effective food-grade acid, causing a 4.4-log reduction in S. Enteritidis at 500 mM. AO caused cellular injury and was effective against a variety of S. Enteritidis strains. Confocal microscopy demonstrated that cells treated with 50 mM and 250 mM AO had significant membrane damage and reduced cellular respiration compared to untreated controls.