Maurice O'Sullivan

Dr. Maurice O'Sullivan

School of Food and Nutritional Sciences, University College Cork, Cork, Ireland
orcid

Research Focus & Metrics

Academic Career Length

38Years (1989-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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13 March 2018 in Foods
Verified
Journal Article
Open access
PDF file
Kieran KilcawleyKieran Kilcawley
Kieran Kilcawley
HFHope Faulkner
Hope Faulkner
HCHolly Clarke
Holly Clarke
Maurice O'SullivanMaurice O'Sullivan
Maurice O'Sullivan
JKJoseph Kerry
Joseph Kerry
There has been a surge in interest in relation to differentiating dairy products derived from pasture versus confined systems. The impact of different forage types on the sensory properties of milk and cheese is complex due to the wide range of on farm and production factors that are potentially involved. The main effect of pasture diet on the sensory properties of bovine milk and cheese is increased yellow intensity correlated to β-carotene content, which is a possible biomarker for pasture derived dairy products. Pasture grazing also influences fat and fatty acid content which has been implicated with texture perception changes in milk and cheese and increased omega-3 fatty acids. Changes in polyunsaturated fatty acids in milk and cheese due to pasture diets has been suggested may increase susceptibility to lipid oxidation but does not seem to be an issue to due increased antioxidants and the reducing environment of cheese. It appears that pasture derived milk and cheese are easier to discern by trained panellists and consumers than milk derived from conserved or concentrate diets. However, milk pasteurization, inclusion of concentrate in pasture diets, cheese ripening time, have all been linked to reducing pasture dietary effects on sensory perception. Sensory evaluation studies of milk and cheese have, in general, found that untrained assessors who best represent consumers appear less able to discriminate sensory differences than trained assessors and that differences in visual and textural attributes are more likely to be realized than flavour attributes. This suggests that sensory differences due to diet are often subtle. Evidence supports the direct transfer of some volatiles via inhalation or ingestion but more so with indirect transfer post rumen metabolism dietary components. The impact of dietary volatiles on sensory perception of milk and dairy products obviously depends upon their concentration and odour activity, however very little quantitative studies have been carried out to date. Some studies have highlighted potential correlation of pasture with enhanced “barny” or “cowy” sensory attributes and subsequently linked these to accumulation of p-cresol from the metabolism of β-carotene and aromatic amino acids or possibly isoflavones in the rumen. p-Cresol has also been suggested as a potential biomarker for pasture derived dairy products. Other studies have linked terpenes to specific sensory properties in milk and cheese but this only appears to be relevant in milk and cheese derived from unseeded wild pasture where high concentrations accumulate, as their odour threshold is quite high. Toluene also a product of β-carotene metabolism has been identified as a potential biomarker for pasture derived dairy products but it has little impact on sensory perception due to its high odour threshold. Dimethyl sulfone has been linked to pasture diets and could influence sensory perception as its odour threshold is low. Other studies have linked the presence of maize and legumes (clover) in silage with adverse sensory impacts in milk and cheese. Considerably more research is required to define key dietary related impacts on the flavour of milk and cheese.

1 February 2013 in Meat Science
Verified
Journal Article
Closed access
BTBrian D. Tobin
Brian D. Tobin
Maurice O'SullivanMaurice O'Sullivan
Maurice O'Sullivan
Ruth M. HamillRuth M. Hamill
Ruth M. Hamill
JKJoseph P. Kerry
Joseph P. Kerry

1 October 2003 in Meat Science
Verified
Journal Article
Closed access
Maurice O'SullivanMaurice O'Sullivan
Maurice O'Sullivan
DBD V Byrne
D V Byrne
HMH Martens
H Martens
LGL H Gidskehaug
L H Gidskehaug
HAH J Andersen
H J Andersen
MMM Martens
M Martens

20 May 2023 in Foods
Verified
Journal Article
Open access
PDF file
EIElena Sofia Inguglia
Elena Sofia Inguglia
ZSZuo Song
Zuo Song
JKJoseph Kerry
Joseph Kerry
Maurice O'SullivanMaurice O'Sullivan
Maurice O'Sullivan
Ruth M. HamillRuth M. Hamill
Ruth M. Hamill
Background: The concept of a clean label is difficult to define, even in common language, as the interpretation of what a “clean” food is differs from one person to another and from one organisation to another. The lack of a unique definition and regulations of what the term “clean” means, along with the growing consumer demand for more “natural” and healthier foods, is posing new challenges for manufacturers and ingredient producers. The meat industry, in particular, has been affected by this new movement owing to negative attitudes and feelings consumers associate with consuming processed meat products. Scope and approach: The review scope is to describe attributes and associations around the “clean” label term by analysing the most recent ingredients, additives and processing methods currently available for meat manufacturers. Their application in meat, plant-based alternatives and hybrid meat/plant products, current limitations and challenges presented in consumer perception, safety and potential impacts on product quality are also presented. Key findings and conclusions: The availability of a growing number of “clean” label ingredients provides a new suite of approaches that are available for application by meat processors to help overcome some of the negative connotations associated with processed meat products and also support plant-based meat alternatives and hybrids.

1 August 2017 in Journal of Dairy Science
Verified
Journal Article
Closed access
TOTom O'Callaghan
Tom O'Callaghan
DMDavid T. Mannion
David T. Mannion
Deirdre HennessyDeirdre Hennessy
Deirdre Hennessy
SMStephen McAuliffe
Stephen McAuliffe
Maurice O'SullivanMaurice O'Sullivan
Maurice O'Sullivan
CSCatherine Stanton
Catherine Stanton
The purpose of this study was to investigate the effects of pasture-based versus indoor total mixed ration (TMR) feeding systems on the chemical composition, quality characteristics, and sensory properties of full-fat Cheddar cheeses. Fifty-four multiparous and primiparous Friesian cows were divided into 3 groups (n = 18) for an entire lactation. Group 1 was housed indoors and fed a TMR diet of grass silage, maize silage, and concentrates; group 2 was maintained outdoors on perennial ryegrass only pasture (GRS); and group 3 was maintained outdoors on perennial ryegrass/white clover pasture (CLV). Full-fat Cheddar cheeses were manufactured in triplicate at pilot scale from each feeding system in September 2015 and were examined over a 270-d ripening period at 8°C. Pasture-derived feeding systems were shown to produce Cheddar cheeses yellower in color than that of TMR, which was positively correlated with increased cheese β-carotene content. Feeding system had a significant effect on the fatty acid composition of the cheeses. The nutritional composition of Cheddar cheese was improved through pasture-based feeding systems, with significantly lower thrombogenicity index scores and a greater than 2-fold increase in the concentration of vaccenic acid and the bioactive conjugated linoleic acid C18:2 cis-9,trans-11, whereas TMR-derived cheeses had significantly higher palmitic acid content. Fatty acid profiling of cheeses coupled with multivariate analysis showed clear separation of Cheddar cheeses derived from pasture-based diets (GRS or CLV) from that of a TMR system. Such alterations in the fatty acid profile resulted in pasture-derived cheeses having reduced hardness scores at room temperature. Feeding system and ripening time had a significant effect on the volatile profile of the Cheddar cheeses. Pasture-derived Cheddar cheeses had significantly higher concentrations of the hydrocarbon toluene, whereas TMR-derived cheese had significantly higher concentration of 2,3-butanediol. Ripening period resulted in significant alterations to cheese volatile profiles, with increases in acid-, alcohol-, aldehyde-, ester-, and terpene-based volatile compounds. This study has demonstrated the benefits of pasture-derived feeding systems for production of Cheddar cheeses with enhanced nutritional and rheological quality compared with a TMR feeding system.

1 December 2012 in Meat Science
Verified
Journal Article
Closed access
BTBrian D. Tobin
Brian D. Tobin
Maurice O'SullivanMaurice O'Sullivan
Maurice O'Sullivan
Ruth M. HamillRuth M. Hamill
Ruth M. Hamill
JKJoseph P. Kerry
Joseph P. Kerry