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Academic HighlightsDr. David Everett

Leprino Foods Professor

California Polytechnic State University, San Luis Obispo

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Current research activitiesInternational and US collaboration

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Structure

FlavorTexture

Digestibility

Release of nutrients and bioactive components

Appearance

Food microenvironment and

safety

The impact of structure and the future of food research

Shelf-life Health

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Encapsulation of bioactive components in food matrices

Ali Rashidinejad, PhD thesis, University of Otago (2015)

  125 ppm 250 ppm 500 ppm

Free 0.69±0.06b 0.63±0.12b 0.57±0.16b

Encapsulated - 0.98±0.02a 0.99±0.05a

Encapsulation of catechin in a cheese matrix

Red arrows show microcapsules containing catechin in cheese; scale bar 5 µm

Protection of labile bioactive compounds under low pH digestive conditions (lessens proliferation of colon cancer cells when using EGCG)Release in GI tract with retention of bioactivity

5Benjamin, O., Silcock, P., Kieser, J., Waddell, J.N., Swain, M.V. & Everett, D.W. Innovative Food Science and Emerging Technologies, 15: 96-103 (2012)

Food sample ingress

Water jacket

Saliva ingress

Air flow

Two output sensors to Powerlab

Actuator

Volatile egress to PTR-MSTongue

PTR-MS

Model mouth

Pressure transducer

Understanding the role of tongue pressure and movement on release of flavor compoundsDevelopment into a model gut for digestion work with bioactive compoundsCollaboration with:• Dental School, University

of Otago, New Zealand• Fraunhofer Institute,

Freising, Germany

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-IN OUT

Product Flow in treatment chamber

Toepfl et al., Emerging Technol. Food Processing, 69-97 (2004)

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E > Ecritical

Reversible pore formation

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E >> Ecritical

Irreversible pore formationIntact bacterial cell membrane

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New processing technologiesPulsed electric fields (PEF)

Non-thermal processes can be applied for food safety reasons, with minimal detrimental effect on enzymes that generate flavor and other quality attributes

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Colloid surface reactions – milk fat globuleLiquid ordered L0 regions rich in sphingomyelin (highly saturated, longer chain) and cholesterol

Liquid disordered region

Two-dimensional reactions on emulsion and other colloidal surfaces to generate texture and flavor reactions

Gallier, S., Gragson, D., Jiménez-Flores, R., Everett, D.W., J. Agric. Food Chem. 58: 4250–4257 (2010)

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Raman confocal spectroscopy

Increasing size

Gallier, S., Gordon, K., Jimenez-Flores, R. & Everett, D.W. Int. Dairy Journal, 21, 402-412 (2011)

1 µm 15 µm9 µm5 µm

A novel technique for visualizing the structural locations of molecules (flavor compounds, bioactives, etc.) that have Raman spectra

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Giant unilamellar vesicle model systems

5 μm 5 μm

GUV generated from electroformation.

Non-fluorescent lipid domains formed with DPPC/DOPE 3/7 mol/mol in a GUV system.

Zheng, H., Jiménez-Flores, R., Gragson, D. & Everett, D.W. J. Agric. Food Chem., 62, 3236-3243 (2014)

Model milk fat globule vesicles to examine surface structures

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Other research activities

Impact of processing conditions during cheese manufacture and salt level on mozzarella textural functionality (industry projects)

Alternative separation methods to extract ingredients from milk Cheese colloidal structural chemistry and impact on flavor and

textural quality Two-dimensional enzymatic surface reactions Extraction of bioactives from food products using

microemulsions

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The future of food research

Future food research will be interdisciplinary:

Structural effects on digestion and delivery of nutrients (structure and nutrition)

Encapsulation strategies for delivery of bioactive components (chemistry and health)

Understanding how structure generates flavor in food products and dictates perception (biochemistry and sensory science)

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Research leadership

Investigator in the Riddet Institute Centre of Research Excellence (New Zealand)

Ongoing sustainable research team of PhD students Interdisciplinary collaboration with researchers at other

universities Development of industry linkages for research Supporting new academic staff through research collaboration Received $1.1 million in research funds

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Teaching leadership

Initiator of the Curriculum Re-development Committee in Food Science

Development of dairy food physical chemistry and process technology curricula

Development of research literacy course Exchange programs with overseas universities

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Service leadership

President (and Fellow) of the NZ Institute of Food Science and Technology

Serve on committees of the International Union of Food Science and Technology, and the International Dairy Federation

Editor of the International Dairy Journal, and a member of three other editorial boards

Reviewer of research grants and publications Member of panel to offer advice to government on science

issues