Volatiles and sensory characteristics of yogurt manufactured by incorporating basil (Ocimum basilicum L.)

Abstract

Purple basil was used as powder or water extract forms in the manufacture of yogurt for possible contribution on its taste and flavour of yogurt. The volatiles were extracted by solid-phase micro-extraction and then determined by gas chromatography-mass spectrometry (GC-MS) system. Effects of the addition of purple basil as powder or water extract form on the volatile composition and sensory characteristics during 3 weeks of storage at 4°C were evaluated. Forty-nine compounds were identified in the volatile composition of yogurt samples, including 12 ketones and aldehydes, 9 esters, 7 acids, 8 alcohols, 9 terpenes, and 4 miscellaneous compounds. Acetoin, ethyl acetate, hexanoic acid, acetic acid, 1-hexenol, 3-hexen-1-ol, 2-ethylhexenol, dL-limonene, and linalool were most frequently identified volatiles in the yogurt samples. The level of linalool, which was main volatile in basil, was higher in powder basil flavoured yogurt samples than those in extracted basil flavoured yogurt samples. Principal component analysis of the GC-MS data showed that use of basil as powder or water extract form significantly changed the volatile profile of yogurt during storage. Also, sensory scores for basil-free yogurt were higher than yogurt samples manufactured by incorporating basil. In conclusion, use of basil enhanced the volatile composition of yogurt, and basil-flavoured yogurt may be offered for consumers as an alternative type of flavoured yogurt.