EFFECT OF TREATMENT PARAMETERS ON THE CAROTENOID EXTRACTION FROM TOMATO PEELS OF BULGARIAN INDUSTRIAL VARIETIES

Abstract

Tomato by-products are an attractive source of natural carotenoids. This study was carried out  to  investigate  the  extractability  of  carotenoids  from  tomato  peels  of  two  Bulgarian  industrial varieties, named “Stela” and “Karobeta”,and to assess the effects of the extraction parameters (time, extraction  steps,  temperature,  solid/liquid  ratio  and  solvent  type)  on  the  yield  of  carotenoids. Individual  carotenoid identification in  dried  tomato  peels  was  carried  out  by using  a  HPLC  system. The  content  of  total  carotenoids,  lycopene  and  β -carotene  in  the  obtained  extracts  was  measured
spectrophotometrically. Carotenoid recovery was significantly (p <0.05) affected by the investigated extraction  parameters.  The  maximum  amounts  of  total  carotenoids  (111.58±2.11  and  76.59±2.13 mg/100g),  β-carotene (54.69±2.15 and 64.70±1.42 mg/100g) and lycopene (49.07±0.19 and 6.51±0.57
mg/100g) extracted from dried tomato peels of “Stela” and “Karobeta” varieties, respectively, were obtained  by  using  acetone  as  solvent,  for  three  successive  extraction  steps  of  30  min,  at  40 ^oC  and solid/liquid ratio of 1:30.  It was experimentally established that tomato peels of “Stela” variety are suitable for lycopene and  β-carotene recovery, while those of “Karobeta”variety for the recovery of β -carotene only.