Bitter Apples For Cider Making - An Alternative

A key property conferred on cider by these polyphenols, particularly the
procyanidins, is the taste perception of bitterness or astringency.
Bitterness, also referred to as “hard” tannin, is associated with lower levels
of polymerization and low procyanidin molecular weight.
Astringency, also referred to as “soft” tannin, is associated with increasing
levels of polymerization and molecular weight.(Lea).
In today’s beverage market, ciders can be made from juice or juice
concentrates derived solely from culinary or dessert apples, or solely from
traditional cider apples. But a considerable number of ciders are made from a
blend of both culinary / dessert and traditional cider apples.
Commercial culinary apple juice concentrate (8 times concentrated = 71
brix) typically contains 1500 – 3000 mg/L polyphenol. This is equivalent to 190 –
375 mg/L at fresh juice strength. Lachman et al (2006) have reported total
polyphenol in juice from table apples ranging from 78 to 697 mg/l with
considerable variation between varieties but even more between analysis
methods. He compared the EBC total polyphenol method with the Folin-
Ciocalteau (FC) method.
Commercial European bittersweet apple concentrate typically contains
9000 – 16000 mg/L polyphenol. This is equivalent to 1100 – 2000 mg/L at fresh
juice strength.
Recent increased popularity of cider both in Europe and Australia lead to
an acute shortage of so called “bittersweet” apple juice and apple juice
concentrate, resulting in poor availability and increased cost
Apples are a perennial crop, so there is substantial cost, infrastructure and
time delay required to increase crop capacity if demand for a particular cultivar
(or group of cultivars) exceeds supply. As there was little or no prospect of
immediate reliable supply, a search for suitable substitutes was undertaken.
Potential commercial sources of polyphenol that were considered for
inclusion in cider production were tea polyphenol, oak tannins, oak chips, and
grape polyphenol. These were taste trialed at a lab scale in a cider base, and
found to be a poor flavour match to cider produced using traditional bittersweet
apple concentrate. There were also physical stability problems with cider
containing these alternatives.
Another potential source was crab apples. These have traditionally been
used in some styles of alcoholic cider. Crab apples have been noted by Shahidi
to produce juices with 390 – 1350 mg/L chlorogenic acid. As chlorogenic acid
comprises around 6-10% of total polyphenols (Shahidi) this implies a total
polyphenolics level in juice from mature crab apples of 3900 – 22000 mg/L. This
compares to reports of juice from table varieties of apple which, when mature,
have implied total phenolics ranging from 15 – 3000 mg/L. However, there are no
commercial quantities of crab apples grown in Tasmania, and juice concentrates
from crab apples also are not known to be available.
Brown at al (2001) have reported total polyphenol levels of 3000 – 6000
mg/kg in apple skin material, and around 15000 mg/kg in apple leaf material. The
proportions of polyphenol classes was not identified, however, it would seem