Fatty acids and volatile compound of cooked green licuri (Syagrus coronata) and naturally ripe licuri almonds from native flora, popularly consumed in Brazil.

The present study was carried out to investigate the proximate composition, fatty acid (FA) profile and volatile compounds (VC) of cooked green licuri (Syagrus coronata) - an unripe stage that is then cooked - and naturally ripe licuri almonds. The FA profiles were determined by gas chromatography (GC) and the VC composition was evaluated using headspace-solid-phase microextraction coupled with GC-MS. The cooked green licuri presented higher moisture, and lower contents of ashes, proteins and lipids than naturally ripe licuri almonds. The FA profiles of cooked green licuri and naturally ripe licuri almonds showed that saturated FAs were predominant (80%) in both samples, and the concentrations of lauric, palmitic, and oleic acids in naturally ripe licuri almonds were higher than those in cooked green licuri. Limonene was the predominant compound in naturally ripe licuri almonds. The main class of VC in the cooked green licuri were aldehydes, with 3-methyl-butanal and furfural being the main species. Alcohols, such as 3-methyl-butanol and 2-heptanol, were the main class of VC in naturally ripe licuri almonds. Among the volatile compounds, 1-hexanol and 2-nonanone contributed to the aroma of cooked green licuri almonds, whereas 2-heptanone, ethanol, and limonene contributed to the aroma of naturally ripe licuri almonds (almonds not subjected to any cooking process). In a word, cooked green licuri and naturally riped licuri almonds, despite having different proximate compositions, present similar fatty acid profile and distinct aromatic characteristics. Therefore, cooked green licuri and naturally riped licuri almonds are an alternative source of nutrient and could be investigated for the use in the food industry to enhance flavor and aroma to new products.

Effect of co-inoculation of Saccharomyces cerevisiae and Lactobacillus fermentum on the quality of the distilled sugar cane beverage cachaça.

UNLABELLED: The effect of Lactobacillus fermentum in co-inoculation with Saccharomyces cerevisiae UFLA CA11 on the quality of cachaça (sugar cane spirit) was evaluated. The co-inoculation was first evaluated in flask fermentation, and subsequently, yeast and bacteria were co-cultured at approximately 10(5) CFU/mL and 10(8) CFU/mL, respectively, in 4 consecutive batches. L. fermentum did not affect the growth or activity (sugar consumption and fermentation rate) of S. cerevisiae UFLA CA11 during fermentation. The physicochemical analysis revealed a higher concentration (Tukey test) of aldehydes (22.07 mg/100 mL anhydrous alcohol) in cachaça produced by co-inoculation. Analysis of volatile compounds using GC-FID demonstrated that cachaça produced by co-inoculation had higher concentrations of acetaldehyde (25.15 mg/L), ethyl acetate (30.17 mg/L), and 2,3-butanedione (170.39 µ/L), while cachaça produced by UFLA CA11 contained higher concentrations of ethyl lactate (1205.98 µ/L), propionic acid (127.97 µ/L), butyric acid (2335.57 µ/L), and 1-pentanol (469.23 µ/L). The lowest concentration of acetic acid measured by HPLC was found in cachaça obtained with UFLA CA11. The sensory analysis, performed using the Mann-Whitney test, revealed that cachaça produced by co-inoculation differed from that produced by UFLA CA11 in taste and aroma. PRACTICAL APPLICATION: This study reports on the use of a mixed culture of Saccharomyces cerevisae and Lactobacillus fermentum to produce cachaça and shows the influence of co-inoculation of yeast and bacteria on the quality of this beverage.

Optimization of fermentation conditions for production of the jabuticaba (Myrciaria cauliflora) spirit using the response surface methodology.

UNLABELLED: The jabuticaba tree (Brazilian grape tree) is a tree native to Brazil that belongs to the Myrtaceae family. The jabuticaba fruit is used in some regions of Brazil to produce juices, jams, wine, and ice cream. In this work, the fermentation conditions (temperature and °Brix) for producing jabuticaba distillate were optimized using the response surface methodology (RSM). The optimal conditions for fermentation were found to be 20 °C and 22 °Brix. In repeated experiments to validate the model, experimental data exhibited good agreement with the predicted data. The distillate jabuticaba beverage showed a peculiar chemical composition with 20 volatile compounds that were identified and quantified. Isoamyl alcohols (2-methyl-1-butanol + 3-methyl-1-butanol) were the most abundant volatile compounds identified in jabuticaba spirit. Sensory analysis by tasters showed overall approval of jabuticaba distillate. In principal component analysis, when the beverage was evaluated by panelists under 24 y old tended to give favorable ratings of aroma and taste, as well as high overall scores. The group of panelists between the ages of 25 and 53 y old generally gave high marks for appearance in the principal component analysis. PRACTICAL APPLICATION: This study describes the study of fermentation conditions of jabuticaba pulp for production of jabuticaba spirit. Based on the results of this work, the proposed method can be an alternative for the use of the jabuticaba fruit, and may provide a new industrial outlet for this fruit.

3-pentanol: a new attractant present in volatile emissions from the ambrosia beetle, Megaplatypus mutatus.

Megaplatypus mutatus (=Platypus mutatus) (Coleoptera: Platypodidae) is an ambrosia beetle that is native to South America. It attacks only standing live trees and causes severe stem breakage and death in commercial poplar (Populus) plantations. Previous work showed that male M. mutatus emits a sex pheromone composed mainly of (+)-sulcatol and sulcatone. We collected male volatile emissions during the hours of maximum emergence by using a specific polar microextraction phase; analyzed the extract by GC-MS; and tested the biological activity of selected compounds in the extract with a walking behavioral assay. Female M. mutatus emerged primarily between 7 and 11 h. In the chemical analyses of volatiles, a third compound, 3-pentanol, was identified in a small percentage of samples. Walking behavioral bioassays with video image analysis showed that at the doses tested, 3-pentanol elicited an attractive response from females.

Conductivity detection of aliphatic alcohols in micellar electrokinetic chromatography using an oscillometric detector.

Although conductivity is usually applied to detect ionic species in capillary electrophoresis (CE), nonionic species can also be detected by their indirect effects on the conductivity of the running electrolyte. This approach was used for detection of aliphatic alcohols in micellar electrokinetic chromatography (MEKC) with an oscillometric detector. Although the detector operates at 600 kHz, for the range of electrolyte concentration used in CE, the response is mainly due to variations of conductivity. A 50 mM phosphate and 50 mM SDS solution was used as running electrolyte and as the solvent for mixtures of some isomers of propanol, butanol, and pentanol. A set of negative peaks was obtained and assigned to the components by spiking the samples. The limits of detection (LOD) ranged from 2.1 mM for 2-methyl-2-propanol to 5.3 mM for 1-pentanol. Due to the high affinity for the interior of the micelles, 1-hexanol could not be easily-detected, but by the addition of 10% methanol to the running electrolyte it was possible. For this electrolyte, the LOD was improved, ranging from 0.8 mM for 2-methyl-2-propanol to 1.5 mM for 1-pentanol. Calibration plots were linear up to 40 mM at least. These results indicate that conductivity may be useful for detection of nonionic species in CE, especially when optical methods can not be conveniently applied.