Zwarte Bessen 6
Even over het gezondheidsaspect.
Het vitamine C gehalte van zwarte bessen is het hoogst van al onze inheemse vruchten. Met een gemiddelde van 181 mg per 100 g verse bessen ligt dit extreem hoog en is volgens de Amerikaanse aanbevelingen voor volwassenen zelfs 3 maal zoveel als de aanbevolen dagelijkse hoeveelheid (ADH). Vergelijk hierbij appelsienen die met 50 mg per 100g vier maal lager scoren. Daarnaast zijn er nog veel secundaire inhoudsstoffen die door voedingswetenschappers als voorbehoedend voor hart – en bloedsomloopstoornissen en kanker erkend worden. Dit zijn de anthocyanen die de pel zwart en het sap zwartrood kleuren. Daarbij zijn de bessen nog rijkelijk voorzien van ballaststoffen en kalium, daarbij ook calcium en ijzer.
Het gehalte aan antioxidanten is wellicht de voornaamste factor voor het bepalen van de gezondheidswaarde. Ze maken de gevaarlijke radicalen onschadelijk.
Ik voeg hieronder een tekst in van het Scottish Crop Research Institute
Fruit quality and nutritional aspects
The main
fruit quality objectives in blackcurrant breeding have traditionally focused on
ascorbic acid (AsA) content. The range of AsA in commercially available
varieties varies from 130 - 200 mg/100 ml juice, but this increases to over 350
mg/100 in some breeding lines and even higher in wild accessions of R. nigrum var. sibiricum. Some reports suggest that
the AsA contained in blackcurrant fruit is more stable than most other sources,
possibly due to the protective effects of anthocyanins and other flavonoids
within the berries. The main period of AsA accumulation coincides with the
berry expansion phase, soon after fertilization, and genotypic rankings of AsA
content established in this early stage remained constant thereafter (Viola et al
2000).
Blackcurrants and other Ribes species are outstanding sources of antioxidants,
both in the form of high ascorbate levels but also in the high concentrations
of polyphenolic compounds that are contained within the fruit. The latter
include flavonoids, such as anthocyanins and flavonols. The amounts of these
compounds present in the berries varies with cultivar, environment and
agronomic practices. The main anthocyanins in blackcurrant are
cyanidin-3-rutinoside, delphinidin-3-rutinoside, delphinidin-3-glucoside and
cyanidin-3-glucoside, and the relative proportions vary between genotypes. For
example, a survey of available germplasm has shown that western European
varieties contain more cyanidin derivatives, whilst Scandinavian varieties
contain a higher proportion of delphinidin derivatives. Since the latter are
generally more stable, many breeding programmes including the SCRI programme
have preferentially selected for a high delphinidin:cyanidin ratio (Brennan 1996) and varieties such as 'Ben Alder' are particularly high in
delphinidins. There are also within blackcurrant fruit minor compounds, such as
cyanidin-3-sophoroside, delphinidin-3-sophoroside and
pelargonidin-3-rutinoside, which collectively amount to ca. 5% of the total
anthocyanins.
The stability of these nutritionally important compounds in blackcurrant during
processing has been assessed, and whilst juice processing can cause
considerable losses of ascorbate, the phenolic compounds are relatively stable
during processing and antioxidant activity is retained in the juice. However,
there may potentially be changes caused within the phenolic compounds by the
processing, which may affect bioavailability. There are at present various
studies worldwide, involving clinical trials, to ascertain how much of the
ingested blackcurrant phenolics are actually taken up by the body and thereby
play a role in proposed health benefits from berry consumption.
Tabel 1 Gemiddelde Voedingswaarde per 100 g verse bes
(Gegevens: United States Departement of Agriculture: Nuttrient Database)
|
Energetische waarde |
264 kJ (63 kcal) |
|
Koolhydraten |
15,4 g |
|
Vetstoffen |
0,4 g |
|
Eiwitten |
1,4 g |
|
Thiamine (Vit. B1) |
0,05 mg |
|
Riboflavine (Vit. B2) |
0,05 mg |
|
Niacine (Vit. B3) |
0,3 mg |
|
Pantotheenzuur ( B5) |
0,395 mg |
|
Vitamine B6 |
0,066 mg |
|
Vitamine C |
181 mg |
|
Calcium |
55mg |
|
Ijzer |
1,5 mg |
|
Magnasium |
24 mg |
|
Fosfor |
59 mg |
|
Kalium |
322 mg |
|
Zink |
0,27 mg |
|
|
|
Tabel 2 Gehalte aan antioxidanten
Zwarte bessen 14 – 50
Blauwe bessen 20 – 45
Frambozen 13 – 22
Aardbeien 9 - 18
Pruimen 9,5
Sinaasappel 7,5
Druiven 7,4 – 18
Appel 2,2
Witte wijn 2