Annex White book.pdf

A4.1.2.1 Saffron humidity and volatile substancesThe ISO organization, nowadays, has published ISO 939:1980, definingthus a method used for humidity detection in spices. This methodcan not apply to saffron due to the large amount of necessary samples.For this reason, the technical specification ISO/TS 3632-2:2003, subsection7, suggests a special determination method for saffron.Determination of the humidity of saffron (threads or powder) and ofits volatile substances is carried out according to following procedure: anexact amount of 2,5 g of saffron is weighed by a precision scale (± 0,001 g)on a well dried microscope glass slide. The slide with the sample is placedin a furnace at 103oC ± 2 o C for 16 hours. Determination of humidity andvolatile substance, is performed according to following formula: WHV =(mo – m1) x (100/mo) %. m0 is the initial sample mass rendered in g andm1 is the mass of the sample after drying (rendered in g).The dried material will be kept in hydrochloric acid ashes for furtherdetermination of the crude ashes according to ISO 928:1997 and ISO930:1997 respectively.A4.1.2.2 Crude ashes in dry matterCrude ashes percentage is calculated in two grams of saffron sample(already used for humidity determination) and according to ISO928:1997. The calculated percentage is approximately at 8%. Followingprocedure is applied: 2 g of saffron are placed in a porcelain capsuleand weighed with a precision of about 0,1 mg. The capsule has beenheated in a chamber for an hour at approximately 550 o C ± 25 o C, thencooled in a dryer and weighed precisely with a variation of 0,1 mg. Thecapsule is heated on a plate until the sample is carbonized. Afterwards,the capsule is placed in a furnace and remains there for 2 hours at550oC ± 25 o C. The ashes are cooled and wetted with water drops thatevaporate in thermostatic bath until they are totally dry. The capsule isheated in the furnace for 1 hour at 550oC ± 25oC and is weighed every30 minutes until weight is stabilized. Heating, cooling and weighingare repeated until the difference between continuous weighing does notexceed 0,5 g.The crude ashes, rendered in mass percentage, are calculated accordingto following formula: Wct = (m2 – m0) x (100/m0)%, where m0 isthe mass of the sole capsule in gram and m1 is the mass of the samplein gram, while m2 is the mass of the capsule and the mass of the crudeashes, rendered in gram.148