Table 1 Properties to control identity and purity of Masquelier’s grape seed extract. The data were provided by the extract’s manufacturer

 Aspect

Fine powder

 Color

Light brown/pinkish

 Odor

Characteristic woody

 Taste

Astringent, bitter

Identification

In house

 UV spectrum (approx. 40 mg/L in ethanol 96%)

λ max = 280 ± 5 nm

λ min = 256 ± 5 nm

 Bate-Smith reaction (approx. 100 mg/L)

λ max = 540–550 nm

Loss on drying

≤10%

Ph. Eur. 01/2005: 20817

Sulphated ashes

≤0.5%

Ph. Eur. 01/2005: 20414

Solubility

conform

Ph. Eur. 6.7: 51100

 1% (w/v) in water

insoluble < 5%

 2% (w/v) in methanol

Soluble

 1% (w/v) in isopropanol

Soluble

 0.01% (w/v) in chloroform

Insoluble

 pH (4% (w/v) in water)

2.5–4.5

In house

Residual solvents

conform

Ph. Eur. 6.7: 20424

 acetone

≤10 ppm

 chloroform

≤10 ppm

 ethanol

≤10 ppm

 ethyl acetate

≤10 ppm

 n-butanol

≤10 ppm

Microbiology

conform

Ph. Eur. 6.7: 50104

 Bacteria

<10000 cfu/g

  Enterobacteria

<100 cfu/g

  Escherichia coli

0 cfu/g

  Staphylococcus aureus

0 cfu/g

  Salmonella

0 cfu/10 g

  Pseudomonas aeruginosa

0 cfu/g

 Yeasts and moulds

<100 cfu/g

Mycotoxins

Comply with Reg. EC 1881/2006

In house

Pesticide/phytosanitary products ^a

≤0.05 ppm

Ph. Eur. 6.7: 20813

Heavy metals (Fe, Cd, Hg, Pb, As)

<1 ppm

Ph. Eur. 6.7: 20408

Polychlorinated biphenyls and dioxins

Comply with Reg. EC 1881/2006

In house