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Although esters were important odorants in light aroma-type liquor, it was still puzzling that sensory interaction between esters made the odor quality of light aroma-type liquor outstanding. The aim of the paper was to investigate perceptual interaction among esters. The odor thresholds of eighteen esters and 35 binary mixture were determined by a three-alternative forced-choice procedure. The relationship between odor threshold and carbon chain length of homologous ethyl esters was investigated. Moreover, 31 binary mixtures present either a synergistic effect or additive action. Furthermore, odor quality and odor intensity were determined by p/τ plot and σ/τ plot, respectively. From the p/τ plot, an ideal sigmoidal function for odor quality was obtained. From the σ/τ plot, for all 120 binary mixtures, just 9 mixtures were in the hyper-additivity area (σ 1.05), and two were in the so-called perfect additivity area (0.95 σ 1.05). Almost one half (48%) showed compromise level. Finally, a significantly difference was observed by flash gas chromatography electronic nose (p .05). Sensory analysis revealed that a mask effect of fruity note was occurred by adding ethyl phenylacetate at various levels (100, 2500, 58,000 ppb) to the fruit recombination and an enhancement effect of floral note was reported by adding phenylethyl acetate at low (1400 ppb) or high level (11,500 ppb). It was noticed that sweet note was significantly enhanced by adding phenylethyl acetate at peri-threshold (3200 ppb).

Aromatic wallpaper was developed in order to provide fragrant atmosphere for inter space with new properties and added value. Micro-encapsulation technology is an effective method to control release of fragrance. If wallpaper is treated with micro-encapsulated fragrance, longer scent holding time is expected. This article reported the detailed preparation processes and analysis of two sorts of wallpapers with gas chromatography-mass spectrometry (GC–MS) and electronic nose (E-Nose). The morphology of blank wallpaper and the aromatic wallpaper were characterized by scanning electron microscopy (SEM). The aroma content of fragrant wallpapers was investigated by head-space solid phase-micro-extraction (SPME) and GC–MS. The employ of an electronic nose to measure the intensity of fragrant release from the wallpaper was also conducted. The release experiments indicated that aromatic wallpaper had the eminent and stable sustained release property. What’s more, the sustained release time of aroma could reach more than 3 months. Meanwhile, the aroma intensity and the comfortable degree were associated with sensory valuation to confirm which one is the best fit for human feelings.

A simple, rapid and solvent-free multi-residue method has been developed and applied to confirm and quantify a series of volatile compounds in five cherry wines by gas chromatography coupled with mass spectrometry (GC–MS). Four parameters (e.g., coating material of fiber, temperature and time of extraction, and addition of sodium chloride in the solution) of headspace solid-phase micro-extraction (HS-SPME) were optimized, resulting in the best extraction condition including 50/30 μm DVB/CAR/PDMS fiber, 45 min and 50 °C of SPME, and 2 g of sodium chloride addition in the wine during the extraction. The SPME had LODs and LOQs ranging from 0.03 to 7.27 μg L−1 and 0.10 to 24.24 μg L−1 for analytic compounds, respectively. Repeatability and reproducibility values were all below 19.8%, with mean values of 12.7% and 10.5%, respectively. Regression coefficients (R2) of detective linearity of the standard curves was higher than 0.9852. Moreover, relative recoveries of analytical targets were achieved in a range of 60.7–125.6% with good relative standard deviation values (≤20.6%). In addition, a principal component analysis (PCA) was used to analyze the aroma profiles of the wines, which indicated that five samples were distinctly divided into two groups based on their different geographical origins and volatile compounds.

Flavors represent a small but significant segment of food industry. Taro gives a pleasant nut-like odor when cooked. Taro flavor can be used in many products, so developing a taro flavor is of interests. This paper concentrates on preparation and simulation of taro flavor according to the notes of taro, which are distinct flavors or odor characteristics. The results show that the notes of taro flavor can be classified as caramellic note, roast note, milky note, beany note, green note, aldehydic note, sweet note, nutty note, vegetative note, and fruity note. According to the notes of cooked taro odor and the raw materials selected, a typical taro flavor formula is given. The taro flavor blended is pleasant, harmonious, and has characteristics of the odor of cooked natural taro.

Reducing sugar, as a biomass energy precursor, can be further transformed to fuel alcohol in a fermentation process by means of micro-organisms or yeast. This study investigated the production of reducing sugars from bean dregs waste by hydrolysis in subcritical water. It was investigated that the effect of reaction temperature, reaction time and CO2 on reducing sugar yield. The optimum hydrolysis technology conditions were obtained. The addition of carbon dioxide led to an increase in reducing sugar yield. The highest yield of total reducing sugars is 65.7% at 300 °C and 360 s. Kinetics was conducted in a temperature range of 260–300 °C. Since the reaction kinetics in sub-critical water is very complicated, a simplified kinetic model to describe the hydrolysis of bean dregs wastes is proposed. The differential equations resulting from the model were fit to experimental data to obtain kinetic rate constants. By means of the Arrhenius plot, the activation energy as well as the pre-exponential factor was determined. A good agreement between the simplified model and the experimental data was obtained. The kinetic parameters provided useful information for understanding the hydrolysis reaction of bean dregs waste. Based on the results, this method could become an efficient method for biomass wastes liquefaction, producing valuable reducing sugars.

The recovery of waste substances is important not only for the prevention of environmental issues, but also for the rational utilization of natural resources. Hydrolysis reaction in sub-critical water is a promising method for the treatment of organic wastes and has been attracting worldwide attention. In this paper, sub-critical water hydrolysis was employed as a method for producing amino acids, reducing sugars, bio-oil and gas fuels from biomass wastes. The current statuses of these useful chemicals production from biomass wastes by hydrolysis in sub-critical water were reviewed. The review indicates that sub-critical water hydrolysis can be an efficient process for recovering useful chemicals from biomass wastes. This method is renewable, sustainable, efficient, and safe for the environment.

In order to improve the utilization of bird wastes, the hydrolysis technology optimization and reaction kinetics for amino acid production by extremely low acids in subcritical water have been conducted. In this experiment, the raw material was chicken intestines and the research target was the yield of amino acids. The effects of reaction temperature, reaction time and H 2 SO 4 concentration in reactant system on amino acid yields were investigated using the orthogonal test and the optimum hydrolysis technology conditions were obtained. The experimental results show that the best hydrolysis technology is: reaction temperature 533 K, reaction time 28 min, H 2 SO 4 concentration in reactant system 0.02 wt.%. Under this condition, the amino acid yield reaches 11.49%. The results of chemical reaction kinetics experiment indicate that the total velocity constants of chicken intestine hydrolysis in subcritical water with H 2 SO 4 concentration in reactant system 0.02 wt.% are 1.52 × 10 −2 , 3.35 × 10 −2 , 11.58 × 10 −2 , and 14.01 × 10 −2 at 473 K, 503 K, 533 K, and 553 K respectively. The reaction kinetics order is 1.52, activation energy is 64.44 kJ/mol and the pre-exponential factor is 1.91 × 10 5 .