2.11 Spoilage of Honey

Question 1

Describe what fermented honey looks like?

Answer 1

Wet, dilute honey on the surface and a yeasty smell.

Dry, lumpy, heaving surface with bubbles as CO2 is given off

Question 2

List the factors required to cause fermentation of stored honey.

Off The Wagon

Answer 2

1 presence of Osmophilic yeasts
• C6H12O6 = yeasts = 2C2H6O +2CO2 Glucose or fructose + yeasts = alcohol and carbon dioxide.
2 Temperature 18-20C
3 Water content more than 17%, usually more than 19%.

Question 3

List the actions the small scale beekeeper can take to prevent fermentation

SEEK

Answer 3

1 Store at temperatures below 13C
2 Ensure moisture content below 17%
3 Ensure container is air tight
4 Kill the yeast - heat honey to 60C for about an hour and cool rapidly

Question 4

Honey spoilage - causes

MUFFSPOF

Answer 4

Medication misused (whilst supers are in place)
Unpleasant odours/tastes (from storage buckets)
Foreign particles (oil from extractor)
Fructose syrup (illegal adulteration (High HMF))
Sugar syrup (inappropriate feeding)
Poor presentation (sticky jars)
Overheating (prolonged exposure to heat causes enzymes to decay and HMF to form, affecting colour (darkens), aroma and flavour (too much heat gives a toffee flavour))
Fermentation (presence of osmophilic yeasts in sufficient quantities, warmth 18-21°C for yeast growth and reproduction, sufficiently high water content for yeast to grow (>17% no fermentation >19% high chance of fermentation)

Question 5

Fermentation conditions

Answer 5

Honey is hygroscopic so will absorb water from a humid atmosphere; at 65% relative humidity honey has a water content of 20.9%w/w
Store honey in air-tight containers at <10°C and at a humidity of less than 65%.
For fermentation to occur ALL of the following are required:
 Osmophilic yeasts
 Temperature 18 – 20 °C
 Water content > 17%
8°-21° Best temperature for high yeast activity
Water content <17% no fermentation >19% high chance
Temperature
<13°C Honey will not ferment
Flash heat 71°C Pasteurised honey kills osmophilic yeasts
Granulation causes water concentration between crystals
They break sugars down into alcohol and carbon dioxide
C6H12O6 -> 2C2H6O + 2CO2

Question 6

Yeasts

Answer 6

Yeasts are everywhere where honey is, it is impossible to remove them but pasteurisation kills them. Commercially: raise the temperature to 71°C then cool rapidly,
Non-commercially: raise the temperature to 60° for one hour
Ideal temperature range for yeast growth is 18-21°C although there will be some growth below this range.
Honey will not ferment if its water content is less than 17%; at a water content above 19% honey will eventually ferment under the above conditions.
Yeasts are unicellular organisms that use sugars as a source of energy for growth and cell division.
They break sugars down into alcohol and carbon dioxide
C6H12O6 -> 2C2H6O + 2CO2
Osmophilic yeasts are those in saturated sugar solutions.

Question 7

Prevention of fermentation

YES

Answer 7

kill the Yeasts – honey (heat to 60°C for one hour and cool rapidly)
Ensure moisture content < 17%
Store at temperature below 13°C

Question 8

How to store honey

Heavenly
Creatures
Treasure
12
New 
Combs

Answer 8

1. Honey is hygroscopic so will absorb water from a humid atmosphere; at 65% relative humidity honey has a water content of 20.9%w/w
2. store honey in Clean, food grade plastic, air-tight containers in vermin proof room at <10°C and at a humidity of less than 65%.
   Temperature: 14°C for granulation, then 10 °C for long term storage to prevent fermentation
   Max 12 months
   Never extract unripe honey
   Wrap comb in airtight trays after draining off any honey after cutting - then freeze

Question 9

Principles of honey storage

Answer 9

No increase in HMF (age, heat)
No decrease in diastase activity (age, heat)
No fermentation (<17°C no fermentation > 19°C high chance)
No contamination from container or extractor (used to store vinegar, oil from extractor)
No loss of F/A (airtight containers)
Store honey in crystallised form in large containers before putting it in jars. For rapid crystallisation into smooth, non-gritty crystals, store it at 14°C (16-18°C according to Hooper).
Thereafter store it in a cool place to prevent fermentation.
Cool storage also maintains Diastase and HMF levels.
Remove impurities before storage or after 24 hours by skimming surface of honey.

Question 10

Signs of Fermentation

Answer 10

Sour flavour
Unpleasant aroma
Streaks (not frosting)
Bubbles on surface caused by CO2
Heaving surface caused by CO2
Co2 
Alcohol
Acetic acid