Fifty years of change to the lipid diets of Australasians-A recap.
Laurence Eyres FNZIFST
History: The situation 50 years ago
In 1972 NZ and Australia were experiencing extremely elevated levels of coronary heart disease much in line with the rest of the Western world. In Australasia cheap dairy and animal fats predominated in most consumer’s diet. Figure 1 (Insert courtesy of Professor Rod Jackson)
Soft unsaturated margarine and olive oil and other vegetable oils were rarely consumed. New Zealand vegetable oils were on import restrictions and were subject to tariffs.
Olive oil of superior quality was only available on prescription and the imported oil was of inferior quality and often fraudulent. The NZ Margarine act (1908) prohibited the manufacture and sale of soft and flavoured margarines which were fast establishing themselves in Europe and the USA. The repeal of this act meant the spread industry could keep developing over many years.
Margarine, named after margaric acid (C 17:0), was named by Meges Mouries from the Latin word meaning pearl. He invented the butter substitute as a cheap substitute for butter in 1869 and he won a prize from Napoleon III. This combined with the invention of catalytic hydrogenation of oils led to a global proliferation of cheap substitutes for butter.
In 1973 New Zealand and Australia both had alarming levels of coronary heart disease. Much later in 1999 after years of change Professor Jim Mann reviewed the effects of nutrition on cardiovascular disease. (Mann,1999)
Abels Ltd in Auckland was started by Albert Abel who had family and shareholding ties with Marrickville Margarine in Sydney. My first boss and friend in the industry was Stan Brooker, a memorable and impressive character in the Food Industry (J. C. Andrews winner). Abels had to combat the Draconian Margarine Act 1908 listed below:
A synopsis of the act is shown in Table 1
Table 1 The NZ Margarine Act
All this started to change in 1973 when the medical fraternity, led by Sir Professor John Scott lobbied the government to allow the production and sale of a special polyunsaturated margarine, we christened Miracle. (Brooker,1976). This had < 20 % saturates contrasting with butter at 63% saturates. The formulation relied on utilising trans 18:1 from hydrogenation as the solid part of the spread instead of saturates. The industry did not realise back then that trans fatty acids were more harmful than saturates. The original blends focused on linoleic acid as the essential fatty acid and did not incorporate linolenic acid, now seen to be vitally important. Spreads, 65% fat (not margarines) have really grown in market share and there is a proliferation of products and brands on the retail shelves.
The control of spreadability
The physical texture of butter, shortenings and spreads is determined by two factors. The first physical property is one of the number of solids at various temperatures. These days this is controlled using analytical instruments such as pulsed NMR. Melting point is quite a simple measurement and depends on the number of tri-saturated glycerides in the product.
Margarine butter wars
The industry fought back the growth of margarine with some cutting, witty and very funny adverts. The industry led by the then Dairy Research Institute, developed firstly fractionated AMF followed by spreadable butter. (Norris, R. and Illingworth, Munro D.) It was believed a truly spreadable butter would sell well overseas because it would overcome the major disadvantage of ordinary butter. So, it proved in the UK market, when spreadable butter was launched there in 1991. In 1997 spreadable butter was first sold in New Zealand supermarkets, and it immediately found a successful niche market.
This was a high-quality product but was expensive compared to vegetable fats. Blends were developed based originally on 50/50 combinations of butter and polyunsaturated margarine. These were delicious and spreadable fat products and originally were known as Anchor Country Soft. Butter had been through incredibly stressful and woeful economic times in the 1980’s due to the restrictions and tariffs imposed by the EU. Perfidious Albion had even threatened to place 6 Anchor UK Directors in Jail due to unpaid taxes and tariffs.
The commission of the European Community proposed that the access level for the import of New Zealand butter into Britain for 1984 be set at 83,000 tonne, reducing by two thousand tonnes per annum to 75,000 tonne in 1988. This was a major reduction from the golden years when NZ exported around 250,000 tonne of butter to Britain. The Council of Agricultural Ministers agreed in part to the commission’s recommendation; the principle of continued access for New Zealand butter into Britain and was guaranteed for a further five-year period but quantities were set only for the first three years. The New Zealand Dairy Board (NZDB) was a statutory board in control of the export of all New Zealand dairy products from its formation in 1923 until 2001. Established in 1923 by the Dairy Produce Act 1923.
In 1987 L.E. was employed to develop markets outside UK for NZ butter products. This led to various targeted fat products for product development at DRI and the dairy company, Bay Milk Products. (Eyres,1989)
In 2001, the Dairy Board was merged with the two largest New Zealand dairy cooperatives (which represented 96% of the industry) to a company initially called GlobalCo, but shortly afterwards renamed Fonterra.
Tallow to palm oil – Bakery fats
In the 1980’s edible tallow became in short supply, so our company started to investigate sourcing RBD palm oil and palm olein from Malaysia. The Palm Oil Research Institute of Malaysia was starting up under the inspiring leadership of Kurt Berger who I had befriended when he was at Lyons in the UK. We spent a lot of time researching formulae to replace tallow. The Malaysian edible oil industry is now huge and has its own marketing and research organisation PORAM.
The palm oil people seconded a technologist to study and try out new formulae. This was a remarkably interesting time and resulted in almost 100% substitution of tallow for palm oil. Of course, in later years palm oil became problematic to use because of environmental issues in Malaysia and Indonesia. Between ourselves and PORIM we researched hydrogenation, interesterification and fractionation, all led to various products for targeted applications.
Trans versus saturates.
Originally in the 70’s saturated fat was replaced by partially hydrogenated fats with elevated levels of trans fatty acids. We spent a lot of time and research in trying selective catalysts to maximise the number of trans fats in the hydrogenated oil. The experimental results produced intense competition amongst the chemists as to who could get the highest trans fatty acids. Then in later years hydrogenated fats were replaced by interesterified blends.
For a full evaluation of the fats used in the Australasian industry see the work by Inturissi and Eyres in see the Australasian Handbook of Edible Oils (O’Connor,2007). pp 214- 269
Studying oxidation primary and secondary products. Frying oils
There are a lot of myths surrounding the use and practise of frying with oils. The main myth that has been around for many years is that the smoke point depends on the type of oil being used. This is blatantly not true and in fact the smoke point bears a direct resemblance and direct correlation with the free fatty acid (F.F.A) level. The type of oil is irrelevant. We have tried to remedy the incorrect statement and have published a paper (Eyres L.,2015).
A small unit to test polar compounds in used frying fat is the Testo 270. This unit shows the acceptable levels for use, 24% – 27% polar material, above these levels is an unacceptable limit for consumption. Breakdown products have been shown to be quite toxic.
During the 1970’s stable long-life tallow based frying fats dominated both the Food and Food service sectors. The premium frying fat, Chefade was sold in bulk, cartons and in 500g retail tubs. It was a premium and very stable solid white fat with a melting point around body temperature of thirty-six degrees. These days it is the Wild West in the fast-food business with cheap uncontrolled fats being imported into the country. This despite the arduous work of the National Heart Foundation in reviewing and recommending healthy fats.
Fatty acid composition
In the edible industry the analysis of fatty acid composition is extremely important. Fast and accurate analysis is required. Traditional cumbersome and long-winded methods were replaced by test tube-based transesterification using alkali catalysts. (Eyres, L.). The table of results for many common oils is now being updated by modern analyses on capillary columns as our analyses were done on packed columns.
Coconut oil and its products
For many years there was a copra (dried coconut) expelling plant in Newmarket, Auckland. Most of the inhabitants put up with the smell of cooked coconut apart from a few dissenters.
The fully refined coconut oil and hydrogenated derivatives were used in specialised fats. The major product group is called confectionery fats. They were used in biscuit fillings, creams, and toffees. In later years following a lot of mistaken media publicity, coconut oil became a fad and a supposedly healthy oil. In conjunction with the Heart Foundation of New Zealand we debunked these claims and showed the coconut oil, whilst OK to use in small quantities, being 90% saturated had an adverse effect on cholesterol levels. (NZ Heart Foundation,2016)
What part did NZ play in marine lipid development?
Green lipped mussel oil (Croft,1998) and Squalene from deep water dogfish (DSIR) were key items of research.
Orange Roughy oil (wax esters) was a short-lived success story and the oil from the fish both became well known as a natural (unintended) laxative and a useful starting material for oleochemicals. (Buisson, D. H.,1982)
We carried out detailed extraction and processing of unique oil from deep water dogfish (DSIR Report 1991-squalene) and later in 2023 a Standard was created. AS 5380:2023 specifies requirements for responsible harvesting of sustainable sources of squalene and shark liver oil, quality parameters and methods for testing and analysis, and requirements for packaging and labelling consumer products, especially when claiming provenance.
Omega-3 phospholipids
As one of several key consultancy projects in 2010 a dietary supplement company approached me to develop a high-quality marine oil supplement with other key bioactives. This became Lester’s oil which is still going well after fourteen years. The University of Auckland then included the oil in a clinical trial which had mixed success. (Fergusson, L., 2020)
Removing impurities from crude oils (refining).
Over many years there have been improvements in the refining, bleaching, and deodorising of edible oils. The finished oils were termed RBD. Historically oils were caustic refined which led to refined oils which were quite easy to bleach and deodorise. In the last 40 years progress has been made in the improvements of physical refining of oils which involves acid degumming, bleaching and high temperature deodorising to remove the free fatty acids in the deodoriser. There have been a few nutritional issues over the years around the production of trans fatty acids and other unwanted side reactions such as MCPD and GE esters.
The control of spreadability
The physical texture of shortenings and spreads is determined by two factors. The first physical property is one of the number of solids at various temperatures. These days this is controlled using analytical instruments such as pulsed NMR. Melting point it is quite a simple measurement and depends on the amount of Tri saturated glycerides in the product. Processing requires modern scraped surface heat of high capital cost. Several plants were installed in the dairy and edible oil industries.
Olive oil and avocado oil in NZ
We take excellent NZ olive oil for granted these days, but it was not always so. It took the challenging work of Margaret Edwards and Olives NZ to achieve this. Now NZ olive oil wins numerous Gold Medals at international shows. For the story of New Zealand and Australian olive oils see the Australasian Handbook of Edible Oils (O’Connor, 2007).
Leandro Ravetti and Rod Mailer were responsible for leading a team which sorted out a sensible Australasian standard for olive and olive pomace oil (Standards Australia, 2011). This standard has led to a marked improvement in the quality of olive oil in Australia, but sadly the NZ industry because of its dependence on imported oils refused to support the adoption. Fraud utilising poor quality olive oils and oils with similar fatty acid composition, is a global problem.
The same team then looked at the development of quality avocado oil, both virgin oil and RBD. (Wong, M. 2012).
Table 2. Specification for RBD Avocado oil.
- FFA as (oleic) < 0.2%
- PV m Eq/kg < 2
- Colour (5.25 “cell) 5Y 0.5 R (Lovibond scale)
- Flavour Bland
- Odour NIL
- Stability measured by AOM 20 hours min.
MCPD (monochloropropanediol) and GE (glycidyl esters) less than the legal global standard (changing).
Analysis and current issues in the lipid world
Trans fats have already been mentioned and they are now virtually banned in the Western World. The issue of MCPD and GE esters is a more complex one. MCPD esters and GE are formed endogenously during the vegetable oil refining process. (C.P. Tan,2013) factors such as the presence of chloride ions, moisture, and partial acylglycerols can further facilitate MCPD esters and/or GE formation. The traditional elevated temperatures of physical refining exacerbates the problem. The EU regulation sets the maximum level for GE at 1 ppm in vegetable oils and fats placed on the final consumer market or used as an ingredient in food. The GE maximum level for vegetable oils and fats destined to produce baby food and processed cereal-based food is set at 0.5 ppm. The maximum level of a 3-MCPD ester is set by the European Commission to be 1.25 ppm for oils and fats.
Liposomes and oleogels as replacements for solid/saturated fats.
Solid fats contribute to the viscosity, hardness, plasticity, and spreadability of fat-containing food products. The mouthfeel and hardness resulting from the crystal network of fat-containing saturated fatty acids are required and currently irreplaceable in many food products such as puff pastry. The market potential of fat substitutes can be decided by two major factors): (a) the size of the market for products in which fat substitutes can be used and (b) their utility. This is likely to be an area of much research around fat emulsions and liposomes. We currently have a university student doing a project on this topic.
Currently there does not seem to be many innovations and changes happening in the edible oil industry, it is a commodity pricing business. But that could change overnight. For researchers and people in the industry and in academia one should always keep an eye on the research literature and see what is coming along. Anyone involved in the edible oil business should consider being a member of the American Oil Chemists Society (AOCS) which have an exceptionally good journal of its own and holds a significant annual conference at which new developments are reported.
This paper was presented to the NZIFST annual conference in July 2023.
Acknowledgements to the people who gave friendship and vital support over the years.
Ruth Eyres, Mike Cundy, Marie Wong, Allan Woolf, George Lim, Sally Xiong, Peter Hawkins, Anne Scott, Selina Wang, Margaret Edwards, Daniel King, Matt Miller, Peter Nichols, Bob Corish, Lynne Fergusson. Dennis Karl, Gero Leson, Geoff Webster, Lucky Inturissi, David Munro, Ralph Timms, Leandro Ravetti, Rod Mailer. Clare Wall, Charmian o’ Connor, Peter Hawkins.
References
Australian Standard, Olive, and Olive Pomace Oils, (2011), AS 5264-2011
Australian Standard for Squalene and Shark Liver Oil, (2023), AS 5380-2023
Brooker, S.G.B. (1976) Food Technology in NZ, JC Andrews address at annual conference
Buisson, D.H., (1982Oil from deep water species, Orange Roughly oil.) et.al. JAOCS (vol 59, no. 9.)
Charmian J. O’Connor, et. al, (2007 Handbook of Australasian Edible Oils), Oils and Fats Specialist Group of NZIC.
Croft J., (1998) A Gift from the Sea, Harland-Barker
Eyres (1989), Linking product development with the marketplace, Fats for the Future, Editor Cambie, R.C. page, 233.
Eyres L., Chemistry in New Zealand, (1979), Fatty acid compositions: Preparation of fatty acid methyl esters and how to determine page 237.
Eyres, Laurence. Frying oils: Selection, smoke points and potential deleterious effects for health (2015) Food New Zealand, Vol. 15, No. 1, Feb/Mar: 30-31
2016 Eyres L, Eyres MF, Chisholm A, Brown RC. , Coconut oil consumption and heart disease, (Nutr Rev. 2016 Apr;74(4):267-80. doi: 10.1093/nutrit/nuw002. Epub Mar 5.
Fergusson, L, and Bobbi Laing, Nutrients (2020,) 12, 1139
Mann, J. Nutrition and Cardiovascular disease (1999), Technical Report no.77, The national Heart Foundation of NZ.
Declining Rates of Coronary Heart Disease in New Zealand and Australia, 1983–1993 Robert Beaglehole, Alistair W. Stewart, Rod Jackson, American Journal of Epidemiology, Volume 145, Issue 8, 15 April 1997, Pages 707–713, https://doi.org/10.1093/aje/145.8.707
Tan, CP., J. Agric. Food Chem. 2013, 61, 3341−3349
Wong, M. Eyres L. and Ravetti, L. (2012), Modern aqueous oil extraction, in Green Vegetable Oil Processing, Editors Walter Farr, AOCS Press