Growing great beer
15 Mar 2022
Aotearoa New Zealand boasts over 200 craft breweries, the highest number of breweries per capita in the world. Locally grown hops support this domestic industry. But it’s not just here that our hops are loved. Each year we export around 1200 tonnes to over 20 countries and, while that accounts for only 1.5% of the total used globally, the unique flavours and clean, green profile of our hops command a premium with buyers and generate in excess of $50 million a year.
A hop garden near Tapawera with the Kahurangi Mountains in the background. In the past, many New Zealand’s hops have been grown in the Tasman district, where they thrive thanks to the free-draining alluvial soils, an even rainfall, light winds and a temperate oceanic climate, but recently growers are planting hops elsewhere in New Zealand. Scientists at Plant & Food Research are looking at the potential for growing hops further afield – from the far north to the far south.
IMAGE BY ROBERT LAMBERTS
It takes a lot to get hops from the ground to beer and even more — around a decade — to breed a new cultivar. The following photos help tell that story.
Plant & Food Research and its legacy organisations have been at the forefront of hop breeding and genetics for around seven decades and have released 22 cultivars to industry, offering a variety of flavours from tropical and citrus to notes of Sauvignon blanc. Around 95% of the commercial hops used locally and exported are from cultivars developed by Plant & Food Research.
Thanks to their interesting flavour profiles that set them apart from traditional hops, Kiwi hops are esteemed internationally. The first breeding efforts, conducted in Motueka, developed disease-resistant cultivars, followed by seedless triploid cultivars. After that, researchers began experimenting with flavour, producing novel cultivars that have put Aotearoa New Zealand on the map and pleased craft brewers the world over.
Hops breeders at Plant & Food Research are legendary. Dr Rudi Roborgh, the original breeder, has an Auckland bar, Dr Rudi’s, named after him. Dr Ron Beatson produced 16 cultivars during his career, with a range of flavours that brewers love, including the recently released Nectaron®, inspired by his name.
New Plant & Food Research hop cultivars, commercialised through grower co-op NZ Hops Ltd, are exported to major brewing companies in 15 countries, with key markets in the USA, Europe, Asia and Australia.
Close-up of a hop plant tendril. Hops are dioecious, which means they have male and female flowers on separate plants, but only the female is used for brewing. Hops are related to cannabis and are both members of the hemp family (Cannabaceae).
IMAGE BY ROBERT LAMBERTS
Hop extracts are filtered for bitter acid analysis. The bitter acid composition is an important characteristic in hops and brewers utilise it to make beer with particular flavour characteristics.
IMAGE BY MINNA PESONEN
Hops are grown on trellises 5m high. To create new seedlings for breeding purposes, researchers cover the flowers on the hops plant with pollination bags. The original germplasm used for hop breeding at Plant & Food Research came from Europe and North America but after decades of breeding Plant & Food Research has a unique germplasm base.
IMAGE BY WARA BULLÔT
Photo of hop cones used for plant variety rights (PVR) which provide the right to propagate varieties for commercial production.
IMAGE BY ROBERT LAMBERTS
Plant & Food Research scientists Dr Ron Beatson and Kerry Templeton smell hops to assess their aroma. If selected, the hops will go to the pilot brewery (the Hop Lab) to make small-scale brews. A panel of trained staff and local experts then test and score the brews for flavour and consumer appeal. Those that make the grade go to industry for growing and trials.
IMAGE BY WARA BULLÔT & ROBERT LAMBERTS
A cross-section of a hop cone showing the active ingredient lupulin (yellow) that gives beer its aroma and flavour. Hops produce three chemical groups important for brewing and brewers originally added them to beer for their antibacterial qualities rather than for flavour. These days scientists are exploring the potential health properties contained in hops.
IMAGE BY ROBERT LAMBERTS
Hop bines (climbing stem of the hop plant) grow on strings that are cut down at the end of the season. The strings run between the ground and the top of the wire. Hops are a perennial plant and die back in winter. Stringing is an annual (springtime) job and once in place the hop bines are trained to wrap around the string.
IMAGE BY ROBERT LAMBERTS
A colour wheel of information on hop cultivars. The breeding programme at Plant & Food Research has developed many cultivars including craft beer ‘rock stars’ like Nelson Sauvin™, Riwaka™, Motueka™ and Nectaron®. These four cultivars are highly sought after here and overseas.
Close-up of hop flowers in early January. They will expand and the mature inflorescences will be ripe by March.
