In Search of China’s Wild Hops
Hop researcher Nie Nan follows the plants from Xinjiang’s trees to Hebei’s mountain crevices, looking for the ingredients of future Chinese beers.
In Xinjiang, Dr Nie Nan（聂楠） found a hop plant climbing a tree. Its cones were large, and the fragrance was so strong that she could smell it from the ground. In the mountains of Hebei, she encountered something quite different: small cones growing in great numbers from plants rooted in cracks between rocks. Some of the hops she found in Hebei and Shaanxi were pink.
Nie leads the hop project at Beijing’s Jingwa centre（北京京瓦农业科技创新中心）. Over the past few years, she and her colleagues have collected hops in five provinces and regions: Xinjiang, Ningxia, Gansu, Shaanxi and Hebei. They bring back seeds, plant material and cones, building a collection from which new breeding work can begin.
I had first met her on our Gansu hop-field visit. When she travelled from Beijing to attend the inaugural China-Grown Hop Beer Competition, my co-host Qi and I caught her during a break in judging to record Beer Matters Podcast. Her account took us well beyond the rows of plants we had visited in Gansu, into the mountains where she searches for hops herself.
Learning where to look
Nie’s route into hops began with sweet potatoes. During her postgraduate studies, she worked on crop genetics and breeding, with much of her attention on molecular research. A chance to work on the Jingwa hop project introduced her to a crop she knew little about. She drank beer, but had never studied the plant that supplied its bitterness and much of its aroma.
Collecting breeding material quickly presented a practical problem. Brewers use the cones of female hop plants; crossing plants to produce new offspring also requires males. Nie knew that from her reading, but recognising one in the field was another matter. “I’ve never seen a male flower,” she recalled asking her mentor. “Where am I going to find one?”
The familiar green cones are easy to spot compared with the much smaller male flowers. Leaves and stems become useful clues. On collecting trips, Nie and a colleague rented a car and watched the vegetation on either side of the road. Their first excursion in Xinjiang, guided by a local partner, helped them learn what to look for: moisture, sunlight, well-drained ground and neighbouring plants the hops could climb.
Botanical records gave them places to start. Once an area looked promising, they could narrow the search using those observations. In Hebei, Nie found hops at elevations around 1,500 metres and as high as 2,000 metres. In those sparsely vegetated mountain habitats, the team took short sections of side shoots, leaving the plants in place.
Pink cones, and a collection in Beijing
The differences between plants were striking. Nie compared the size of the Xinjiang cones with the Cascade cones familiar to brewers. The mountain plants in Hebei had much smaller cones, but produced them densely. Pink colouring appeared in more than one place, including both Hebei and Shaanxi.
Back in Beijing, she was watching to see how those plants behaved over successive growing seasons. Was the colour a consistent characteristic of a particular plant, or a response to temperature and other conditions? At the time of our conversation, the collected plants were in their second year at the centre. Several seasons of observation would help answer that question.
Their origins were another part of the investigation. A hop found outside a farm might have escaped cultivation. Nie considered the local history of planting, the distance from cultivated land and the presence of seed-bearing plants when assessing what she found. Remote mountain populations offered especially interesting material to study.
Keeping that material alive was work in itself. Some collections failed to establish after the move to Beijing. Nie described starting plants in pots indoors, then moving them through the greenhouse towards field planting. The collection then held roughly 28 accessions: separate sources of seeds and plants to observe, compare and use in breeding.
A plant that can grow well here
For Nie, local adaptation is a central reason to make those collecting trips. Moving a familiar variety to a different climate can change when it flowers and matures, and how its brewing compounds develop. A name on a planting label cannot tell the whole story of how that hop will perform in a new place.
Plants already growing locally offer possible breeding partners. Their ability to survive in those conditions is worth investigating alongside their aroma and chemistry. Nie is interested in how this material might contribute to crosses with other varieties. Heat and drought also belong in that work: a useful hop needs to perform in the field as well as in the glass.
The flavour target remains open. People have asked whether her team could breed the citrus and tropical-fruit character associated with American hops. Her starting point is to understand the collection she already has. Which plants contain useful levels of bittering compounds or oils? What do their aromas suggest? How might they meet a brewer’s needs?
Those questions allow room for different kinds of beer. An appealing hop might have a quieter aroma, contribute well to a blend, or suit a particular style. Nie wants the plants’ own characteristics, together with brewers’ experience, to help determine the direction of the research.
Getting brewers involved early
Developing a good hop variety can take more than a decade, Nie told us. That means years of selection, growing trials and evaluation. She would like breweries to become involved early, helping to shape the work and supporting experiments while the plants are still being assessed.
There is already a practical connection with brewing. Jingwa supplied fresh, undried hops from its outdoor plots in Beijing for beers entered in the competition. Getting them to breweries required careful cold transport; in the arrangements we discussed, distribution was largely limited to Beijing, Tianjin and Hebei. Working nearby made that kind of fresh-hop brewing possible.
The competition also gave researchers a way to hear how brewers and judges experienced the hops. Laboratory measurements can describe alpha acids and essential oils. Brewing shows how those ingredients behave in a recipe, with a particular yeast, and what a drinker actually finds in the finished beer.
Nie was keen to taste the entries made with Jingwa’s fresh hops. I offered to find those beers after judging so we could try them together. After collecting plants from trees and mountain rocks, nurturing them in Beijing and sending hops out to brewers, this was a part of the work she was especially curious to see: what had ended up in the glass.
Listen to the conversation
Beer Matters Podcast · Episode 212 · In Mandarin