Aims: To develop a PCR-based protocol for the rapid, sensitive and specific detection of Curtobacterium flaccumfaciens pv. flaccumfaciens (Cff) in bean seeds. Methods and Results: A pair of PCR primers (CffFOR2-CffREV4), targeting the sequence of a cloned DNA fragment of 550 bp amplified in Repetitive-sequence-based-PCR (Rep-PCR) experiments, were designed and shown to specifically amplify a 306-bp DNA fragment using Cff DNA as template. Moreover, this PCR protocol was demonstrated to successfully detect Cff in naturally infected bean seeds in 36 h. Conclusions: A specific, highly sensitive and rapid PCR assay for the detection of Cff was achieved. Significance and Impact of the Study: Cff is a seed-borne bacterium on the EPPO A2 quarantine list; this procedure may be useful for routine diagnosis of Cff, overcoming the problems of conventional techniques.

There are many interactions that occur between taste and aroma that may impact perception. The main objective of this study was to ascertain whether the aroma fraction of wine should be considered when investigating relationships between chemical composition and sensory perception of mouthfeel. Chardonnay wines with different mouthfeels were produced by altering the fermentation temperature (15˝C and 21˝C) of the alcoholic and malolactic fermentations (MLF) as well as the timing of MLF and the presence of a non-Saccharomyces yeast during alcoholic fermentation. Napping ® and Ultra-flash-profiling were conducted using a panel of white winemakers. Each procedure was conducted twice: once with retro-nasal aroma (+R) and once without retronasal aroma (´R). Napping ® results showed that retronasal aroma impacted mouthfeel perception. Ultra-flash profiling of +R and´R displayed similar descriptive terms used. Several terms appear to be related to retronasal aroma as they were used in +R and not in´R. It is unclear if these terms are due to interactions or due to associated learning. These results suggest that for some mouthfeel terms the volatile fraction plays a role and, to establish relationships between chemical composition and mouthfeel perception, it is important to consider both the volatile and nonvolatile wine fractions.

Malolactic fermentation (MLF) is an important process in wine production due to the resulting reduction in acidity. MLF is typically induced by the addition of Oenococcus oeni after the completion of alcoholic fermentation (AF), but can occur concurrent with AF by co-inoculation of O. oeni with Saccharomyces cerevisiae. This study investigated the effect of MLF inoculation timing and temperature (15 °C and 21 °C) and the presence of the non-Saccharomyces yeast Torulaspora delbrueckii on Chardonnay wine aroma and mouthfeel. Aroma composition was measured using headspace solid-phase microextraction-gas chromatography mass spectrometry (HS-SPME-GCMS). Mouthfeel attributes of the wines produced were assessed by a winemaker panel, using Napping® and Ultra-flash profiling. Significant differences in aroma composition and mouthfeel perception were found based on MLF timing and inoculation conditions, as well as between temperatures. Temperature had a greater impact on the aroma composition for sequential inoculations, while there were little differences based on the temperature of concurrent fermentations. Treatment type and temperature also affected the chemical composition of finished wines. Mouthfeel was impacted, although not as strongly as aroma composition. These findings demonstrate the usefulness of various MLF practices to influence the sensory qualities of a Chardonnay wine.