No abstract

The aroma-active compounds in the extra, first, and third grades of ylang-ylang essential oils (YYEO) from Comoros and Madagascar were identified by gas chromatography-mass spectrometry with olfactometry (GC-MS/O) using an aroma extract dilution analysis (AEDA) technique. In the previous study, the authors investigated differences in volatile compound profiles between YYEO of different grades and regions using GC coupled with a flame ionization detector (FID) and GC-MS. This study follows up with identification of the aroma-active compounds present in YYEO of various grades from both origins and to profile the aroma of those oils. For the first time, principal component analysis (PCA) on AEDA logarithmic flavor dilution (LFD) data was performed, in comparison with the corresponding PCA on GC-FID-MS data. Based on AEDA data, 21 aroma-active compounds were found across all samples and grades of YYEO, with 8 common ones previously identified by GC-FID. Linalool had the highest odor activity and is the major component of YYEO, followed by geraniol, although the latter only appeared as a much smaller peak in the chromatogram. Other trace compounds such as eugenol and vanillin were also found to be significant to the aroma of YYEO. Using PCA on resulting LFD data, YYEO from Comoros were found to have spicier odor qualities as compared to those from Madagascar. The main contributors that determine the difference in a spicy aroma profile of Comoros and Madagascar oils are vanillin, methyl eugenol, and trans-cinnamyl acetate.

Chemical composition of ylang‐ylang essential oil is affected by the geographical origins of flowers used for extraction. This study aimed to determine the compositional difference between the extra, first and third grades of ylang‐ylang essential oil from Comoro Islands and Madagascar. The oils were characterized by both gas chromatography‐mass spectrometry (GC‐MS) and gas chromatography‐flame ionization detector (GC‐FID) in conjunction with principal component analysis (PCA). A total of 124 volatile compounds were identified and quantified by GC‐MS and GC‐FID. Twenty‐two compounds that made up 85% to 90% of the oils were shortlisted to compare across grades and geographical origins. The PCA showed that the ylang‐ylang essential oils are clustered according to grade and origin based on their compositions. Analysis of variance was performed to determine the statistical significance of the differences between each compound across extra, first and third grades of ylang‐ylang essential oil from Madagascar and Comoros. The oils of Madagascar are dominating in geranyl acetate, cis‐α‐farnesene, benzyl benzoate, humulene and caryophyllene, while in those of Comoros, cinnamyl acetate, benzyl salicylate, trans‐farnesyl acetate and α‐farnesene are found to be higher. It is possible to verify the origin and grade of an unspecified source of ylang‐ylang essential oil from the biplot of the 22 compounds.

Summary This study aimed to investigate the effects of plant‐based proteins (i.e. chickpea protein concentrate [CP] and soymilk powder [SM]) and fats (i.e. sunflower oil [SO] and coconut oil [CO]) in substituting dairy ingredients to develop plant‐based frozen desserts. The physicochemical, nutritional and sensory properties of the frozen desserts were evaluated. As compared to the dairy‐based frozen dessert, the plant‐based ones had comparable nutritional profiles with higher dietary fibre contents, which increased viscosities in the mix, resulting in improved meltdown properties. The frozen desserts containing both CP and SM, regardless of the types of fat (3CP3SM‐SO and 3CP3SM‐CO), received higher sensory scores for texture, mouthfeel, taste and overall acceptance. These findings suggest that plant‐based ingredients have the potential to create functional frozen desserts that are high in protein and energy, making them an ideal food supplement for the elderly who are at risk of malnutrition. due to chewing challenges and declining appetites.