Food Science Commons^™

Synthesis And Antimicrobial Evaluation Of Carbohydrate And Polyhydroxylated Non-Carbohydrate Fatty Acid Ester And Ether Derivatives, Aoife Smith, Patricia Nobmann, Gary Henehan, Paula Bourke, Julie Dunne

Articles

A series of fatty acid ester and ether derivatives have been chemically synthesised based on carbohydrate and non-carbohydrate polyhydroxylated scaffolds. The synthesised compounds, along with their corresponding fatty acid monoglyceride antimicrobials, were evaluated for antimicrobial activity against Staphylococcus aureus and Escherichia coli. Of the derivatives synthesised several of the carbohydrate based compounds have antimicrobial efficacy comparable with commercially available antimicrobials. The results suggest that the nature of the carbohydrate core plays a role in the efficacy of carbohydrate fatty acid derivatives as antimicrobials.

Inhibition Of Adhesion Of Streptococcus Mutans To Hydroxylapatite By Commercial Dairy Powders And Individual Milk Proteins, Rachel Halpin, Maeve O'Connor, Dolores O'Riordan, Michael O'Sullivan, Damien Brady

Articles

The aim of this study was to investigate the inhibitory effect of various dairy powders and milk constituents on the adhesion of a clinical isolate of Streptococcus mutans to hydroxylapatite (HA), an analogue of tooth enamel. Adhesion of a microorganism to a cell surface such as epithelial cells or tooth enamel is considered to be the first step in pathogenesis. Inhibiting this process may have therapeutic effects in vivo. The adherence assays were performed by incubating S. mutans with HA in the presence of each test material for 45 min, followed by centrifugal separation of the HA. Unbound bacteria were …

Assessing The Effect Of Product Variability On The Management Of The Quality Of Mushrooms (Agaricus Bisporus), Catherine Barry-Ryan, Jesus Maria Frias, Leixuri Aguirre, Helen Grogan

Articles

To study the shelf-life of mushrooms, over 25 batches were subjected to three storage temperatures (T) (5, 15 and 25 ◦ C) and three storage relative humidity (RH) levels (70, 80 and 90%). The effect of T and the RH on the kinetics of quality attributes of the batches was studied by measuring water activity, turgor, colour (L, a* and b* in the Hunter Scale) and weight loss of three different tissues (cap, gills and stipe) of the mushroom. Linear mixed effect models, comprising polynomial models to describe quality kinetics and allowing for batch-to-batch and inside-batch nested variabilitystructure, were built. …

The Anti-Microbial Efficacy Of Plant Essential Oil Combinations And Interactions With Food Ingredients, Jorge Gutierrez, Catherine Barry-Ryan, Paula Bourke

Articles

The objective of this study was to evaluate the efficacy of plant essential oils (EOs) in combination and to investigate the effect of food ingredients on their efficacy. The EOs assessed in combination included basil, lemon balm, marjoram, oregano, rosemary, sage and thyme. Combinations of EOs were initially screened against Bacillus cereus, Escherichia coli, Listeria monocytogenes and Pseudomonas aeruginosa using the spot-on-agar test. The influence of varying concentrations of EO combinations on efficacy was also monitored using E. coli. These preliminary studies showed promising results for oregano in combination with basil, thyme or marjoram. The checkerboard method was then used …

Recent Applications Of Chemical Imaging To Pharmaceutical Process Monitoring And Quality Control, A. A. Gowen, Colm O'Donnell, Patrick Cullen, S. Bell

Articles

Chemical Imaging (CI) is an emerging platform technology that integrates conventional imaging and spectroscopy to attain both spatial and spectral information from an object. Vibrational spectroscopic methods, such as Near Infrared (NIR) and Raman spectroscopy, combined with imaging are particularly useful for analysis of biological/pharmaceutical forms. The rapid, non-destructive and non-invasive features of CI mark its potential suitability as a process analytical tool for the pharmaceutical industry, for both process monitoring and quality control in the many stages of drug production. This paper provides an overview of CI principles, instrumentation and analysis. Recent applications of Raman and NIR-CI to pharmaceutical …

Antibiotic Resistance In Foodborne Pathogens- A Cause For Concern?, Ciara Walsh, Seamus Fanning

Articles

The widespread use of antibiotics in food animal production systems has resulted in the emergence of antibiotic resistant zoonotic bacteria that can be transmitted to humans through the food chain. Infection with antibiotic resistant bacteria negatively impacts on public health, due to an increased incidence of treatment failure and severity of disease. Development of resistant bacteria in food animals can result from chromosomal mutations but is more commonly associated with the horizontal transfer of resistance determinants borne on mobile genetic elements. Food may represent a dynamic environment for the continuing transfer of antibiotic resistance determinants between bacteria. Current food preservation …

Transfer Of Ampicillin Resistance From S. Typhimurium Dt104 To E. Coli K12 In Food, Ciara Walsh, Geraldine Duffy, R. O'Mahoney, D. A. Mcdowell, Seamus Fanning

Articles

Aims:  To investigate the transfer of antibiotic resistance from a donor Salmonella Typhimurium DT104 strain to a recipient Escherichia coli K12 strain.

Methods and Results:  Mating experiments were conducted in broth, milk and ground meat (beef) at incubation temperatures of 4, 15, 25 and 37°C for 18 and 36 h. Ampicillin-resistance transfer was observed at similar frequencies in all transfer media at 25 and 37°C (10⁻⁴ to 10⁻⁵ log₁₀ CFU ml g⁻¹, transconjugants per recipient) for 18 h. At 15°C, transfer was observed in ground meat in the recipient strain (10⁻⁶, log_{10 …}

Use Of Neutral Electrolysed Water (Ew) For Quality Maintenance And Shelf-Life Extension Of Minimally Processed Lettuce, Daniel Rico, Ana Belen Martin-Diana, Catherine Barry-Ryan, Jesus Maria Frias, Gary Henehan, José Barat

Articles

Experiments were conducted to determine the effectiveness of different treatments based on the use of neutral electrolysed water (EW) on fresh-cut lettuce. EW was diluted to obtain different free chlorine concentrations (120, 60 and 12 ppm) and compared with standard washing treatment of 120 ppm chlorine solution. Shelf-life quality and safety markers were studied at the beginning and at the end of the 7-day storage at 4 ºC. The use of EW decreased the respiration rate of the samples which might be related with the observed reduction in microbial spoilage. The use of EW also increased the activity of a …

Antioxidant Activity Of Spice Extracts And Phenolics In Comparison To Synthetic Antioxidants, M. Hossain, N. Brunton, Catherine Barry-Ryan, Ana Belen Martin-Diana, M. Wilkinson

Articles

The antioxidant capacity of 30 spices used frequently in ready meals and a selection of key compounds from spices were investigated in the current study using ferric reducing antioxidant properties (FRAP), 2,2'-azinobis(3-ethylebenzothiaziline-6-sulfonate) (ABTS) and microsomal lipid peroxidation (MLP) assays. Antioxidant capacities of the spice extracts were compared to 5 popular synthetic antioxidants [buylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butylated hydroquinone (TBHQ), propyl gallate (PG) and octyl gallate (OG)]. Results showed that clove extracts had the highest antioxidant capacity as measured by FRAP, ABTS and MLP assays. Extracts from garlic powder were the lowest ranked of all the spices examined. Synthetic …

Relevance For Food Safety Of Applications Of Nanotechnology In The Food And Feed Industry, Iona Pratt, Catherine Adley, Gordon Chambers, Wayne Anderson

Articles

The application of nanotechnology in the food and feed industry offers many potential benefits for both consumers and manufacturers.The ultrafine dimensions of nanoparticles, and consequently their very large surface area, enable them to function more effectively than conventional macro-scale structures in many applications. Nanotechnology is however a relatively new area of science and the benefits and risks associated with its use in the food and feed industry are not fully understood at this time.This brings with it new challenges in ensuring the safety of food and feed that has been produced with the aid of nanotechnology. This report provides an …

Optimisation Of Steamer Jet-Injection To Extend The Shelf Life Of Fresh-Cut Lettuce, Daniel Rico, Ana Belen Martin-Diana, Catherine Barry-Ryan, Gary Henehan, J. Barat, Jesus Maria Frias

Articles

Optimisation of short time blanching (steaming) was investigated using response surface methodology by analysing quality and microbial and nutritional markers over the shelflife of packaged fresh-cut lettuce. Steamer treatment time (5–10 s) and storage (1–10 days) were used as independent factors in order to optimise the process. Longer treatments (>10 s) were not feasible because of extensive damage caused to lettuce tissue. Significantly (p < 0.05) higher values of luminosity (L*), greenness (−a*) and sensory panel scores (fresh appearance, general acceptability and absence of browning) were obtained with samples treated for longer times with the steamer. Activity of browning-related enzymes present in photosynthetic tissue decreased in all the cases, however, longer treatment time (7.5–10 s) was needed with vascular tissues to reduce to similar activity values. These differences could be explained by the variation in tissue thickness. The longest steam treatment (10 s) reduced and maintained significantly (p < 0.05) lower mesophilic load than shorter treatments (5–8.5 s). However, significant (p < 0.05) decreases in vitamin C and carotenoids were observed in samples treated with longer treatments. Steamer treatment of 10 s could be considered the optimum time for maintaining the shelflife (mainly texture and browning) of fresh-cut lettuce for 7–10 days in optimum conditions.