Not to be semantically confused with : Bastard Balm (Melittis melissophyllum),
Bastard Agrimony (Aremonia agrimonioides), Bastard Cabbage (Rapistrum rugosum), Bastard Toadflax (Thesium humifusum) or
Tall Ramping-fumitory (Fumaria bastardii) [plants with similar names belonging to differing families].
Bastard Service Tree (aka
German Service-tree) is the hybrid of:
??? (Sorbus × pinnatifida) with
??? (Sorbus × semipinnata) which are both hybrids themselves!
Another source has it that
Bastard Service-tree is the diploid hybrid between:
Rowan (Sorbus aucuparia) and
Common Whitebeam (Sorbus aria) which is much simpler, but possibly wrong(?)
Bastard Service-tree is rare native occurring only in several parts of the UK but is also cultivated and planted.
Some similarities to : other
Whitebeam trees but less so to
Rowan trees (species of Sorbus)
The ripe berry (actually a pome) is only edible when cooked. When raw the pomes are extremely astringent containing
ParaSorbic Acid which has a 6-membered ring and is also a lactone - (as well as
Sorbic Acid - aka
2,4-HexaDienoic Acid), the former of which causes indigestion if the berries/pomes are eaten and possible kidney damage. When cooked the
ParaSorbic Acid is converted to
Sorbic Acid rendering them non-toxic.
Simple Acids within Sorbus species
Parasorbic Acid is synthesized within the 'berries' (which are actually pomes) of Bastard Service-Tree (and quite possibly many other Sorbus species) as the precursor to making
Sorbic Acid. ParaSorbic Acid is both an astringent and is toxic to consume causing indigestion, nausea and sometimes death.
Sorbic Acid (aka
2,4-HexaDienoic Acid) is a linear molecule and colourless solid which slowly sublimes and is only slightly soluble in water. It too is present in the 'berries' of Bastard Service-tree (but was first found in unripe berries of the Rowan Tree) - and which also need cooking before they are safe to eat for much the same reason. Sorbic Acid or its salts with Sodium, Potassium or Calcium, are used as a preservative in foods and drinks to prevent moulds growing. The salts are more usually used as they are more soluble in water. It is to be found in both cheese and bread.
The berries are edible only when cooked. Cooking converts the
Parasorbic Acid to
Sorbic Acid (they are nearly isomers of each other - except that Sorbic Acid has one extra hydrogen molecule).
Sorbic Acid is a linear molecule and is acidic, whereas ParaSorbic Acid has a 6-membered
Pyranone ring and is a