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Zahra Zolfaghari

PhD Candidate
Food Science

Zahra Zolfaghari

Contact

Ext 8258
Email zahra.zolfghari@postgrad.otago.ac.nz
Location CSB 220

Characterization of unifloral honeys based on volatile compounds, physicochemical properties and bioactivity.

Supervised by Associate Professor John Birch and Associate Professor Graham Eyres.

About

I completed my MSc at Ferdowsi University of Masahhad, in my home country of Iran.
Being a postgraduate student in the Food Science department is a wonderful experience because of the positive and active atmosphere among students and staff.
Being accepted into a PhD program at the University of Otago has allowed me to study at a highly respected University and experience another country. Dunedin is safe and friendly; it is a beautiful city with many green areas, bike routes, hiking tracks, scenic peninsula and amazing wildlife of penguins, sea lions, fur seals and petrels.

Project Outline

Unifloral honey is a premium product predominantly produced from one single nectar source valued for its distinctive sensory characteristics. Because of this higher commercial value, unifloral honeys are subject to fraud through mislabelling and mixing with cheaper honeys.

Traditionally, unifloral honey is judged based on melissopalynology (the identification and counting pollens in honey). This method requires expertise in pollen morphology and the availability of a comprehensive collection of reference pollen grains. Results of melissopalynology can be confounded as the pollen content of honey can be altered by the action of bees or contamination by the actions of apiarists. In some cases, pollens are not detectable or distinguishable from morphologically similar pollens by melissopalynology.

Honey contains high concentrations of sugars, water, minerals, proteins, vitamins, organic acids, flavonoids, phenolic acids and enzymes. These components not only define the physical properties of honey, they also present different patterns of saccharides, volatile compounds and phenolic compounds that give an indication of the botanical origin of honey.

My objective is to evaluate different criteria of characterising the properties and composition of unifloral honey including sugar profile, volatile compounds and chiral compounds in order to define typical characteristics of unifloral honeys.

Aroma is one of the typical features of honey and is largely dependent on volatile compounds that may come from the nectar or honeydew collected by bees. Therefore, screening volatile compounds may distinguish the floral origin.

I am applying two strategies to distinguish these compounds that may identify the floral origin. First, producing a volatile profile that represents a “finger print” of the product which is due to the floral origin using proton transfer reaction mass spectrometry (PTR-MS). My second strategy is identifying specific floral markers for each type of unifloral honey using gas chromatography-mass spectrometry (GC-MS).

Many volatile compounds present in honey are chiral and exist as pair of enantiomers. These chiral compounds are mostly synthesized in plants by enzymatic reactions, which are not dependant on the conditioning or storage of the honey. Therefore, they provide a tool to characterise the origin of unifloral honeys.  

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Publications

Anwar, M., Birch, E. J., Ding, Y., & Bekhit, A. E.-D. (2022). Water-soluble non-starch polysaccharides of root and tuber crops: Extraction, characteristics, properties, bioactivities, and applications. Critical Reviews in Food Science & Nutrition, 62(9), 2309-2341. doi: 10.1080/10408398.2020.1852388

Bunga, S., Birch, J., Carne, A., & Bekhit, A. E.-D. A. (2020). Colour and chemical composition of Karasumi-like Chinook salmon (O. tshawytscha) roe relevant to its quality. Proceedings of the 2019 International Joint Conference on JSAM and SASJ, and CIGR VI Technical Symposium joining FWFNWG and FSWG Workshops. (pp. 113). Saitama City, Japan: Japanese Society of Agricultural Machinery and Food Engineers. [Abstract]

Loi, C. C., Eyres, G. T., Silcock, P., & Birch, E. J. (2020). Application of a novel instantized glycerol monooleate ingredient in a protein-stabilized oil-in-water emulsion. Foods, 9(9), 1237. doi: 10.3390/foods9091237

Mungure, T. E., Farouk, M. M., Birch, E. J., Carne, A., Staincliffe, M., Stewart, I., & Bekhit, A. E.-D. A. (2020). Effect of PEF treatment on meat quality attributes, ultrastructure and metabolite profiles of wet and dry aged venison Longissimus dorsi muscle. Innovative Food Science & Emerging Technologies, 65, 102457. doi: 10.1016/j.ifset.2020.102457

Li, T., Lloyd, K., Birch, J., Wu, X., Mirosa, M., & Liao, X. (2020). A quantitative survey of customer perceptions of smart food packaging in China. Food Science & Nutrition, 8, 3977-3988. doi: 10.1002/fsn3.1563

Lloyd, K., Mirosa, M., & Birch, J. (2019). Active and intelligent packaging. In L. Melton, F. Shahidi & P. Varelis (Eds.), Encyclopedia of food chemistry (Vol. 3). (pp. 177-182). Amsterdam, the Netherlands: Elsevier. doi: 10.1016/B978-0-08-100596-5.22421-9

Chapter in Book - Research

Okoro, O. V., Sun, Z., & Birch, J. (2019). Thermal depolymerization of biogas digestate as a viable digestate processing and resource recovery strategy. In K. Azad (Ed.), Advances in eco-fuels for a sustainable environment. (pp. 277-308). Duxford, UK: Woodhead Publishing. doi: 10.1016/B978-0-08-102728-8.00010-3

Chapter in Book - Research

Amini Khoozani, A., Birch, J., & Bekhit, A. E.-D. A. (2018). Resistant starch preparation methods. In G. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.22491-8

Chapter in Book - Research

Clarkson, C., Birch, J., & Mirosa, M. (2018). Locusts as a source of lipids and proteins and consumer acceptance. In G. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.22420-7

Chapter in Book - Research

Kanokruangrong, S., Birch, J., & Bekhit, A. E.-D. A. (2018). Processing effects on meat flavor. In G. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.21861-1

Chapter in Book - Research

Loi, C. C., Eyres, G. T., & Birch, E. J. (2018). Protein-stabilised emulsions. In G. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.22490-6

Chapter in Book - Research

Mungure, T. E., Bekhit, A. E.-D., Carne, A., Roohinejad, S., Mallikarjunan, K., & Birch, J. (2018). Application of HPLC in characterisation of triacylglycerols and detection of adulteration in cold pressed seed oils. In G. W. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.22526-2

Chapter in Book - Research

Okoro, O. V., Sun, Z., & Birch, J. (2018). Lipases for biofuel production. In G. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.21650-8

Chapter in Book - Research

Rashidinejad, A., & Birch, J. (2018). Xanthine oxidase in dairy foods. In G. W. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.21648-X

Chapter in Book - Research

Tantamacharik, T., Carne, A., Agyei, D., Birch, J., & Bekhit, A. E.-D. A. (2018). Use of plant proteolytic enzymes for meat processing. In M. G. Guevara & G. R. Daleo (Eds.), Biotechnological applications of plant proteolytic enzymes. (pp. 43-67). Cham, Switzerland: Springer. doi: 10.1007/978-3-319-97132-2_3

Chapter in Book - Research

Tengku-Rozaina, T. M., & Birch, E. J. (2018). Thermal analysis for lipid decomposition by DSC and TGA. In G. W. Smithers (Ed.), Reference module in food science. Elsevier. doi: 10.1016/B978-0-08-100596-5.21674-0

Chapter in Book - Research

Mungure, T. E., Stewart, I., Birch, J., & Bekhit, A. E.-D. A. (2017). NMR spectroscopy applications in the meat industry. In A. E.-D. A. Bekhit (Ed.), Advances in meat processing technology. (pp. 343-384). Boca Raton, FL: CRC Press. doi: 10.1201/9781315371955

Chapter in Book - Research

Rashidinejad, A., Bremer, P., Birch, J., & Oey, I. (2017). Nutrients in cheese and their effect on health and disease. In R. R. Watson, R. J. Collier & V. R. Preedy (Eds.), Nutrients in dairy and their implications for health and disease. (pp. 177-192). London, UK: Academic Press.

Chapter in Book - Research

Birch, J., & Bell, M. (2011). Biodiesel: Enzymatic production. In D. R. Heldman, M. B. Wheeler & D. G. Hoover (Eds.), Encyclopedia of biotechnology in agriculture and food. (pp. 95-98). Boca Raton, FL: CRC Press. doi: 10.1081/E-EBAF

Chapter in Book - Research

Han, J., Silcock, P., Bell, M., & Birch, J. (2011). Lipase-catalyzed production of biodiesel from tallow [Reprint from Journal of ASTM International (2010) 7(1). doi: 10.1520/STP49365S

Chapter in Book - Other

Anwar, M., Birch, E. J., Ding, Y., & Bekhit, A. E.-D. (2022). Water-soluble non-starch polysaccharides of root and tuber crops: Extraction, characteristics, properties, bioactivities, and applications. Critical Reviews in Food Science & Nutrition, 62(9), 2309-2341. doi: 10.1080/10408398.2020.1852388

Journal - Research Article

Amini Khoozani, A., Birch, J., & Bekhit, A. E.-D. A. (2020). Textural properties and characteristics of whole green banana flour produced by air-oven and freeze-drying processing. Journal of Food Measurement & Characterization, 14, 1533-1542. doi: 10.1007/s11694-020-00402-7

Journal - Research Article

Amini Khoozani, A., Kebede, B., Birch, J., & Bekhit, A. E.-D. A. (2020). The effect of bread fortification with whole green banana flour on its physicochemical, nutritional and in vitro digestibility. Foods, 9(2), 152. doi: 10.3390/foods9020152

Journal - Research Article

Li, T., Lloyd, K., Birch, J., Wu, X., Mirosa, M., & Liao, X. (2020). A quantitative survey of customer perceptions of smart food packaging in China. Food Science & Nutrition, 8, 3977-3988. doi: 10.1002/fsn3.1563

Journal - Research Article

Loi, C. C., Eyres, G. T., Silcock, P., & Birch, E. J. (2020). Application of a novel instantized glycerol monooleate ingredient in a protein-stabilized oil-in-water emulsion. Foods, 9(9), 1237. doi: 10.3390/foods9091237

Journal - Research Article

Loi, C. C., Eyres, G. T., Silcock, P., & Birch, E. J. (2020). Preparation and characterisation of a novel emulsifier system based on glycerol monooleate by spray-drying. Journal of Food Engineering, 285, 110100. doi: 10.1016/j.jfoodeng.2020.110100

Journal - Research Article

Mungure, T. E., Birch, E. J., Ponnampalam, E. N., Stewart, I., Mohamed Ahmed, I. A., Al-Juhaimi, F. Y., & Bekhit, A. E.-D. A. (2020). Conjugated linoleic acid and cholesterol oxidative products generated in hot boned beef Semimembranosus muscle as affected by rigor temperature, ageing and display time. Foods, 9(1), 43. doi: 10.3390/foods9010043

Journal - Research Article

Mungure, T. E., Farouk, M. M., Birch, E. J., Carne, A., Staincliffe, M., Stewart, I., & Bekhit, A. E.-D. A. (2020). Effect of PEF treatment on meat quality attributes, ultrastructure and metabolite profiles of wet and dry aged venison Longissimus dorsi muscle. Innovative Food Science & Emerging Technologies, 65, 102457. doi: 10.1016/j.ifset.2020.102457

Journal - Research Article

Amini Khoozani, A., Bekhit, A. E.-D. A., & Birch, J. (2019). Effects of different drying conditions on the starch content, thermal properties and some of the physicochemical parameters of whole green banana flour. International Journal of Biological Macromolecules, 130, 938-946. doi: 10.1016/j.ijbiomac.2019.03.010

Journal - Research Article

Brown, P., Relish Consortium, including Siebers, R., Birch, J., & Zhou, Y. (2019). Large expert-curated database for benchmarking document similarity detection in biomedical literature search. Database, 2019, baz085. doi: 10.1093/database/baz085

Journal - Research Article

Loi, C. C., Eyres, G. T., & Birch, E. J. (2019). Effect of milk protein composition on physicochemical properties, creaming stability and volatile profile of a protein-stabilised oil-in-water emulsion. Food Research International, 120, 83-91. doi: 10.1016/j.foodres.2019.02.026

Journal - Research Article

Loi, C. C., Eyres, G. T., & Birch, E. J. (2019). Effect of mono- and diglycerides on physical properties and stability of a protein-stabilised oil-in-water emulsion. Journal of Food Engineering, 240, 56-64. doi: 10.1016/j.jfoodeng.2018.07.016

Journal - Research Article

Okoro, O. V., Sun, Z., & Birch, J. (2019). Techno-economic assessment of a scaled-up meat waste biorefinery system: A simulation study. Materials, 12(7), 1030. doi: 10.3390/ma12071030

Journal - Research Article

Zhang, H., Birch, J., Ma, Z. F., Xie, C., Yang, H., Bekhit, A. E.-D., & Dias, G. (2019). Optimization of microwave-assisted extraction of bioactive compounds from New Zealand and Chinese Asparagus officinalis L. roots. Journal of Food Science & Technology, 56(2), 799-810. doi: 10.1007/s13197-018-3540-0

Journal - Research Article

Zhang, H., Birch, J., Pei, J., Mohamed Ahmed, I. A., Yang, H., Dias, G., … Bekhit, A. E.-D. (2019). Identification of six phytochemical compounds from Asparagus officinalis L. root cultivars from New Zealand and China using UAE-SPE-UPLC-MS/MS: Effects of extracts on H2O2-induced oxidative stress. Nutrients, 11(1), 107. doi: 10.3390/nu11010107

Journal - Research Article

Zhang, H., Birch, J., Xie, C., Yang, H., & Bekhit, A. E.-D. (2019). Optimization of ultrasound assisted extraction method for phytochemical compounds and in-vitro antioxidant activity of New Zealand and China Asparagus cultivars (officinalis L.) roots extracts. Food Chemistry, 294, 276-284. doi: 10.1016/j.foodchem.2019.03.012

Journal - Research Article

Bekhit, A. E.-D. A., Shavandi, A., Jodjaja, T., Birch, J., Teh, S., Ahmed, I. A. M., … Saeedi, P., & Bekhit, A. A. (2018). Flaxseed: Composition, detoxification, utilization, and opportunities. Biocatalysis & Agricultural Biotechnology, 13, 129-152. doi: 10.1016/j.bcab.2017.11.017

Journal - Research Article

Clarkson, C., Mirosa, M., & Birch, J. (2018). Consumer acceptance of insects and ideal product attributes. British Food Journal, 120(12), 2898-2911. doi: 10.1108/bfj-11-2017-0645

Journal - Research Article

Clarkson, C., Mirosa, M., & Birch, J. (2018). Potential of extracted Locusta migratoria protein fractions as value-added ingredients. Insects, 9(1), 20. doi: 10.3390/insects9010020

Journal - Research Article

Okoro, O. V., Sun, Z., & Birch, J. (2018). Catalyst-free biodiesel production methods: A comparative technical and environmental evaluation. Sustainability, 10(1), 127. doi: 10.3390/su10010127

Journal - Research Article

Okoro, O. V., Sun, Z., & Birch, J. (2018). Experimental evaluation of a polystyrene sulphonic acid resin catalyst in the hydrolysis of low-grade lipids from the meat processing industry. Biomass & Bioenergy, 116, 49-59. doi: 10.1016/j.biombioe.2018.06.001

Journal - Research Article

Okoro, O. V., Sun, Z., & Birch, J. (2018). Prognostic assessment of the viability of hydrothermal liquefaction as a post-resource recovery step after enhanced biomethane generation using co-digestion technologies. Applied Sciences, 8(11), 2290. doi: 10.3390/app8112290

Journal - Research Article

Tengku-Rozaina, T. M., & Birch, E. J. (2018). Effects of low temperature solvent fractionation on the thermal oxidative stability and antioxidant activity of refined hoki oil and its derived fractions. European Journal of Lipid Science & Technology, 120, 1800140. doi: 10.1002/ejlt.201800140

Journal - Research Article

Zhang, H., Birch, J., Xie, C., Yang, H., Dias, G., Kong, L., & Bekhit, A. E.-D. (2018). Optimization of extraction parameters of antioxidant activity of extracts from New Zealand and Chinese Asparagus officinalis L root cultivars. Industrial Crops & Products, 119, 191-200. doi: 10.1016/j.indcrop.2018.03.066

Journal - Research Article

Zhang, H., Birch, J., Yang, H., Xie, C., Kong, L., Dias, G., & Bekhit, A. E.-D. (2018). Effect of solvents on polyphenol recovery and antioxidant activity of isolates of Asparagus Officinalis roots from Chinese and New Zealand cultivars. International Journal of Food Science & Technology, 53(10), 2369-2377. doi: 10.1111/ijfs.13829

Journal - Research Article

Okoro, O. V., Sun, Z., & Birch, J. (2017). Meat processing dissolved air flotation sludge as a potential biodiesel feedstock in New Zealand: A predictive analysis of the biodiesel product properties. Journal of Cleaner Production, 168, 1436-1447. doi: 10.1016/j.jclepro.2017.09.128

Journal - Research Article

Rashidinejad, A., Birch, E. J., Hindmarsh, J., & Everett, D. W. (2017). Molecular interactions between green tea catechins and cheese fat studied by solid-state nuclear magnetic resonance spectroscopy. Food Chemistry, 215, 228-234. doi: 10.1016/j.foodchem.2016.07.179

Journal - Research Article

Rashidinejad, A., Birch, E. J., Sun-Waterhouse, D., & Everett, D. W. (2017). Addition of milk to tea infusions: Helpful or harmful? Evidence from in vitro and in vivo studies on antioxidant properties. Critical Reviews in Food Science & Nutrition, 57(15), 3188-3196. doi: 10.1080/10408398.2015.1099515

Journal - Research Article

Tirgar, M., Silcock, P., Carne, A., & Birch, E. J. (2017). Effect of extraction method on functional properties of flaxseed protein concentrates. Food Chemistry, 215, 417-424. doi: 10.1016/j.foodchem.2016.08.002

Journal - Research Article

Gao, F., & Birch, J. (2016). Oxidative stability, thermal decomposition, and oxidation onset prediction of carrot, flax, hemp, and canola seed oils in relation to oil composition and positional distribution of fatty acids. European Journal of Lipid Science & Technology, 118(7), 1042-1052. doi: 10.1002/ejlt.201500208

Journal - Research Article

Gao, F., Yang, S., & Birch, J. (2016). Physicochemical characteristics, fatty acid positional distribution and triglyceride composition in oil extracted from carrot seeds using supercritical CO2. Journal of Food Composition & Analysis, 45, 26-33. doi: 10.1016/j.jfca.2015.09.004

Journal - Research Article

Mungure, T. E., Bekhit, A. E.-D. A., Birch, E. J., & Stewart, I. (2016). Effect of rigour temperature, ageing and display time on the meat quality and lipid oxidative stability of hot boned beef Semimembranosus muscle. Meat Science, 114, 146-153. doi: 10.1016/j.meatsci.2015.12.015

Journal - Research Article

Okoro, O. V., Sun, Z., & Birch, J. (2016). Meat processing waste as a potential feedstock for biochemicals and biofuels: A review of possible conversion technologies. Journal of Cleaner Production, 142(Part 4), 1583-1608. doi: 10.1016/j.jclepro.2016.11.141

Journal - Research Article

Rashidinejad, A., Birch, E. J., & Everett, D. W. (2016). A novel functional full-fat hard cheese containing liposomal nanoencapsulated green tea catechins: Manufacture and recovery following simulated digestion. Food & Function, 7, 3283-3294. doi: 10.1039/c6fo00354k

Journal - Research Article

Rashidinejad, A., Birch, E. J., & Everett, D. W. (2016). Antioxidant activity and recovery of green tea catechins in full-fat cheese following gastrointestinal simulated digestion. Journal of Food Composition & Analysis, 48, 13-24. doi: 10.1016/j.jfca.2016.02.004

Journal - Research Article

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