Shelf life determination of Yayik butter fortified with spice extracts

Sage (Salvia officinalis L.), cinnamon (Cinnamomum zeylanicum), rosemary (Rosmarinus officinalis L.), clove (Syzygium aromaticum L.), sumac (Rhus coriaria L.), oregano (Origanum vulgare L.), ginger (Zingiber officinale), caraway (Cuminum cyminum L.) and thyme (Thymus vulgaris L.) extracts were added at two concentrations (0.2 and 0.5%) to yayik butter. The butter samples were stored at two different temperatures, 4 degrees C and 25 degrees C. Product acceptability was monitored following the Weibull Hazard sensory method where the end of shelf life was the time at which 50% of panellists found the product unacceptable. Ginger, thyme and cinnamon extracts increased the shelf life of yayik butter and were comparable to the synthetic preservatives sorbic acid and BHA. The shelf life of the samples stored in the refrigerator was approximately twice as long as the samples stored at room temperature.