Stimulants and Hop Flashcards
Tea - Camellia sinensis
Theaceae
Origin: southeast asia, highlands
Optimal climate: 18-20°C all year
Today China, India, Sri Lanka
Harvest organ: 2 young leaves + bud
Compounds: Theobromin, -phyllin
Hop - Humulus lupulus
Family Moraceae = Cannabaceae
Perennial, dioecious climbing plant
Diploid (2n = 2x = 20; x = 10)
First use: Egypt; Germany: 700 n.Chr.
Wildtypes of hop widespread (Eur, Asia, Am, Austr); origin unknown
Harvest organ: female inflorescences (‚umbels‘, Dolden / Rispen)
Components: essential oils, resin acids: humulone, lupulin
Other relevant species: Humulus japonicus (Japanese hop) - 2n = 16 chromosomes, diploid
umbels without brewing, but pharmaceutical value
Humulus species
H. japonicus
H. lupulus
H. yunnanensis
Which lesson can you learn from hop?
Interesting because of secondary metabolites, use as stimulant (like many plants shown previously)
Globally still grown on small area
It requires a high degree of automation and technology to be produced in reliable quality and at acceptable prices
If you want to scale up any random stimulant plant, you might need to come up with comparable investment in technology and agronomy as well
Product of Hop - taste of beer
Hop gives beer its characteristic bitter taste and aroma
Serves as preservative
Promotes protein decantation and durability of foam
Exclusively hop umbels (female inflorescences) are used
A small proportion of hop production (< 0,5 %) is used in pharma industry for sedant production (sedative effect of lupulin)
German ‚Reinheitsgebot‘ was put in place 1516 (hop, malt, water)
Beer brewing and hop
Barley is germinated (Amylase breaks down starch into maltose and hexoses)
Then it is dried (at 85-100°C) to malt
The malt is being milled
Yeast and hop are added and the slurry is heated, cooled, has to rest in a complex sequence of steps to deliver the final product
Original function of hop: increase beer durability
Product: the female umbel flowers
Bracts contain numerous lupulin glands and yellow lupulin corns with bitter substances (e.g. lupulin) and essential oils
Umbels are harvested after flowering, but prior to seed maturity
Each umbel consists of ca. 60 flowers
Use of 170-400 g hop/hl beer:
o Bitter substances (15-25% of DM)
o Tannins (2-6% of DM)
o Essential Oils (0.5-2.5% of DM)
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biology of hop
hop is dioecious plant
male & female hop plants can only be distinguished via flowers
hop production globally
Germany
China
USA
Czec
Rest
Hop production
Reproduction via cuttings
Plant populations are used for 20-30 a
Vines are supported by a scaffold of 8 to 10 m high masts and crosswires
Vines develop new each year from the rootstock and climb clockwise, using hairs for attachment
Two vines per plant allowed; rest cut back
Warm weather essential during umbel growth (which proceeds until August)
Hop quality is defined by content of resins, etheric oils and tannins (up to 25% ‚bitter substances‘ in dry weight)
Development of hop
page 19
Hop production in CH
15 growers, 2390 ar, 52‘271 kg dried umbels (yield: 2 t/ha)
Specific costs of hop production: 28’000 SFr/ha
At a specific yield of 23 kg/ar, production costs: 1220 SFr/100 kg
The costs are much higher than the prices on the world market!
Swiss hop production covers approx. 10% of local demand
Environment & Soil - hop
The cultivation of hop is concentrated in special regions due to the special requirements of hop (mild climate, where also grapes can be cultivated): E.g. close to Lake Constance / Bodensee
Optimal climate:
High temperatures during main growth phase (June – end of August)
Precipitation of 800 – 1000 mm/year Rootstock has high chilling and frost tolerance
Fertilization - hop
Sequestration of nutrients at yields of 18 dt/ha (dry weight):
N: 120 kg/ha;
P2O5: 40 kg/ha;
K2O: 110 kg/ha;
CaO: 150 kg/ha;
MgO: 25 kg/ha
Fertilization with organic manure is feasible.
Effects of different macronutrients:
N: promotes growth. Excess retards maturation, promotes spread of diseases and affects brewing value.
P: promotes content of bitter substances. Deficiency: blue – brownish leaves.
K: promotes formation of colour and bitter substances. Excess lowers brewing
quality. Deficiency: brownish leaves.
Harvest
Harvest point: umbels have closed, lupulin corns are yellow, and hop aroma developed
Manual harvest: branches are cut at 1.5 m height, loaded on a wagon, and driven to a hop picker.
→ picking of the umbels
→ cleaning through wind and gravity
→ drying to 10.5% humidity (at 58°C)
→ packaging
