Stable isotope dilution assay and HS-SPME-GCMS quantification of key aroma volatiles of Australian pineapple (Ananas comosus) cultivars.

Pineapple aroma is one of the most important sensory quality traits that influences consumer purchasing patterns. Reported in this paper is a high throughput method to quantify in a single analysis the key volatile organic compounds that contribute to the aroma of pineapple cultivars grown in Australia. The method constituted stable isotope dilution analysis in conjunction with headspace solid-phase microextraction coupled with gas-chromatography mass spectrometry. Deuterium labelled analogues of the target analytes purchased commercially were used as internal standards. Twenty-six volatile organic compounds were targeted for quantification and the resulting calibration functions of the matrix -matched validated method had determination coefficients (R2) ranging from 0.9772 to 0.9999. The method was applied to identify the key aroma volatile compounds produced by popular pineapple cultivars such as 'Aus Carnival', 'Aus Festival', 'Aus Jubilee', 'Aus Smooth (Smooth Cayenne)' and 'Aussie Gold (73-50)', grown in Queensland, Australia. Pineapple cultivars varied in its content and composition of free volatile components, which were predominantly comprised of esters, followed by terpenes, alcohols, aldehydes, and ketones.

Review of the Aroma Chemistry of Pineapple (Ananas comosus).

Pineapple (Ananas comosus), one of the most flavorful and popular tropical fruits consumed worldwide, is known to contain many volatile organic compounds (VOCs) at varying concentrations. Much attention has been paid to understand which VOC plays a significant role in the sensory aroma notes of the fruit. Though, nearly 480 VOCs have been identified to date using different analytical techniques, only 40 compounds are reported to contribute to the unique flavor of pineapple. A consolidated database of the reported VOCs and key aroma compounds of pineapple is currently not available. This review discusses the available published data regarding the analytical methodologies, volatile profile of different varieties of pineapple at different maturities, and their characteristic aroma compounds. The output of this review is a subset of key pineapple aroma volatiles that can be targeted in analytical method development for utilization in varietal improvement or other research of pineapple.

Rice Bran Makes a Healthy and Tasty Traditional Indonesian Goat Meatball, 'Bakso'.

Meatballs are popular in Asia and traditionally made from beef or chicken with tapioca (≈8% wt/wt) as filler. Tapioca has a high glycaemic index (GI); therefore, rice bran was evaluated as a substitute to create a healthier meatball of acceptable quality. Substitution of tapioca with rice bran (100:0; 75:25, 50:50; 25:75; 0:100% tapioca: % rice bran) decreased the starch content (7.8 to 3.3%) and GI (56.08 to 43.85) whilst increasing the protein (10.9 to 12.8%) and fibre (8.1 to 10.3%) contents. Although consistency (995 to 776 N/mm) was affected, firmness (90.6 to 90.5 N) and shear force (300 to 312 N) were only slightly affected by the ratio of tapioca to rice bran. Sensory analysis revealed that the goat meatball with the substitution of tapioca with up to 25% rice bran was deemed acceptable by 40 Indonesian consumers.

Sensory properties of yellow pea and macadamia honeys from conventional and flow hive extraction methods.

BACKGROUND: The process of harvesting honey is time consuming and labor intensive. A new system, the Flow Frame, has drastically simplified the harvesting process, enabling honey to be extracted directly from the hive with minimal processing. The sensory profile of honey is influenced, first, by botanical origin and subsequently by processing and storage parameters. A reduction in harvest processing may thus influence the sensory profile of honey harvested from FFs compared to that of honey produced from conventional processing. To test this hypothesis, two monofloral honeys (macadamia and yellow pea) were harvested from FFs, or by conventional honey extraction. Sensory profiling using conventional descriptive analysis was carried out for each floral source with an experienced trained panel. RESULTS: The two monofloral honeys harvested using the FF system had significantly (p < 0.05) higher floral and cleaner aftertaste sensory scores than the honey extracted using commercial (C) methods that involve the use of heat and centrifugation. CONCLUSION: The flow system retains honey's natural sensory properties compared to harvesting methods that require heat and centrifugation. © 2019 Society of Chemical Industry.

Feasibility study on the use of visible and near-infrared spectroscopy together with chemometrics to discriminate between commercial white wines of different varietal origins.

The use of visible (vis) and near-infrared spectroscopy (NIR) was explored as a tool to discriminate between samples of Australian commercial white wines of different varietal origins (Chardonnay and Riesling). Discriminant models were developed using principal component analysis (PCA), principal component regression (PCR), and discriminant partial least-squares (DPLS) regression. The samples were randomly split into two sets, one used as a calibration set (n = 136) and the remaining samples as a validation set (n = 133). When used to predict the variety of the validation set samples, the DPLS models correctly classified 100% of Riesling and up to 96% of Chardonnay wines. These results showed that vis-NIR might be a suitable and alternative technology that can be easily implemented by the wine industry to discriminate Riesling and Chardonnay commercial wine varieties. However, the relatively limited number of samples and varieties involved in the present work suggests caution in extending the potential of such a technique to other wine varieties.