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This study reports on an environment-friendly renewable and zero formaldehyde-emission urea-oxidized starch (U-OSt) adhesive based on native corn starch. The adhesive was prepared by polycondensation reaction of oxidized starch and urea. The morphology, molecular structure, crystalline structure, shear strength and viscosity of the adhesive, the native and oxidized starch were instrumentally investigated. The influence of processing factors was studied, such as the oxidizer content, the urea content and the addition of titanium dioxide nanoparticle (nano-TiO2). The results show the adhesive has an excellent comprehensive performance at urea content of 50% (w/w, dry starch basis) while 5.0% (w/w, dry starch basis) KMnO4 as oxidizer. The dry shear strength was increased by 16.9% by adding of nano-TiO2 content of 1.5% (w/w, dry starch basis), and the corresponding viscosity was 4100 mPa s. It is found appropriate amount of nano-TiO2 played a complementary effect between adhesive and adherend, which enhanced the adhesive property and stability of adhesive.

Improving the microbial degradation capacity of food waste (FW) is a great challenge due to its acidity and high salinity. In this paper, an anti-acidification and salt-tolerant microbial consortium (AASTMC) obtained from acid and salinity mutagenesis of Bacillus amyloliquefaciens, Bacillus cereus, Yarrowia lipolytica, and Trichoderma reesei was used to degrade residential food waste. The process parameters that influenced the degradation rate of organic matter were identified by response surface methodology (RSM) with a central composite design (CCD). The effect of inoculation amount, temperature, and bulk density on the degradation rate of organic matter decreased in turn. The degradation rate of organic matter reached 94.87% under the optimum parameters of inoculation amount: 5%, bulk density: 0.04 g/cm3, and temperature: 32.33°C.

To characterise the volatile aroma compositions of Chinese congou black teas, four types were analysed by quantitative descriptive sensory analysis, gas chromatography–mass spectrometry (GC–MS) and gas chromatography–olfactometry (GC–O). The aroma of Chinese congou black tea was described using six sensory terms: ‘Roasted’, ‘Sweet’, ‘Malty’, ‘Green grassy’, ‘Floral’ and ‘Woody’. A total of 64 compounds including alcohols (20), aldehydes (12), ketones (12), esters and lactones (9), pyrazines (7) and other compounds (4) were identified and quantified in four Chinese black tea samples. The highest amount of volatile aroma compounds was found in Tanyang congou black tea (TY) (29.8 mg/kg), followed by Dianhong congou black tea (DH) (29.4 mg/kg), Keemun congou black tea (KM) (24.1 mg/kg) and Yixing congou black tea (YH) (23.6 mg/kg). Through aroma extract dilution analysis (AEDA) on the black tea extract, the flavour dilution factor (FD factor) ranged from 41 to 46. Trans-linalool oxide in DH, geraniol in TY, DH and KM were identified with the highest flavour dilution (FD = 4096) factors. The relationship between tea samples, sensory attributes and aroma-active compounds was modelled by partial least squares regression (PLSR), and the PLSR analysis revealed that pentanal showed a significant and positive correlation with the ‘Malty’ attribute, (Z)-3-hexen-1-ol showed a significant and negative correlation with the ‘Green grassy’ attribute, 2-methylpyrazine showed a significant and negative correlation with the ‘Floral’ attribute, cis-linalool oxide, trans-linalool oxide and nerolidol showed a significant and positive correlation with the ‘Woody’ attribute, cis-6-nonen-1-ol and 2-methylpyrazine showed a significant and negative correlation with the ’Woody‘ attribute.

Functionalized nano-starch particles, designed for the adsorption of heavy metals in wastewater, were prepared by a nano-processing, a halogenated grafting modification, a grafting copolymerization of surface-initiated atom transfer radical polymerization (SI-ATRP) and a quaternized modification of native corn starch. The influence of the synthesis process variables, such as the hydrolysis time, the concentration of monomer, the molar ratio of copper bromide (CuBr) to 2, 2'-bipyridine (bpy) and the graft copolymerization temperature on the properties of the products were studied. The morphology, molecular structure, crystalline structure of the functionalized nano-starch and its derivatives were characterized by Fourier transform-infrared spectroscopy (FT-IR), 1H nuclear magnetic resonance (1H-NMR) spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and transmission electron microscope (TEM). The functionalized nano-starch showed strong adsorption for chromate and could be used as an effective wastewater treatment agent. Its adsorption capability could be almost totally regenerated by an easy process.

A fast method based on normal-phase high-performance liquid chromatography with UV detection was applied to determine the tocopherols in aromatic peanut oil (APO) and four refined vegetable oils (soybean, sunflower, maize, and rapeseed oils). Our results showed that the tested oils varied greatly on the content of tocopherol isomers, especially on α- and γ-tocopherol concentrations. Consequently, (α+γ)-tocopherol (297.9–393.2 mg kg−1) and α-/γ-tocopherol (1.05–2.13) were successfully applied as discriminating parameters for detecting the adulteration of APO with above four refined vegetable oils. Furthermore, APO was mixed with the four oils (at the levels of 5, 10, 15, 20 and 25 g/100 g, w/w) to determine whether the tocopherol analysis is a better approach than fatty acid profiling for detecting APO adulteration. Our results showed that for tocopherols, our detection limits were 5 g/100 g for soybean oil and 10 g/100 g for other three oils in APO, showing a higher sensitivity than fatty acids profile based method for detecting APO adulteration. Thus, our newly developed method is an alternative and innovative tool for fast and cost-effective detection of the adulteration of APO with soybean, sunflower, maize, and rapeseed oils.

In this study, volatile compounds of five varieties of mandarin juices [Tankan, Miyagawa, Mashui (MS), Skiranui, and Ponkan (PG)] were investigated by gas chromatography-olfactometry (GC-O) and gas chromatography-mass spectrometry (GC-MS). A total of 47 volatile compounds were identified by GC-MS. Partial least-squares regression was used to process the mean scores from sensory evaluation by panelists of volatile compounds and samples. The sample PG was associated with "fruity", "floral", and "sweet" notes, while MS was correlated with "green" and "peely" notes. In addition, 36 aroma-active compounds, including esters, alcohols, aldehydes, ketones, and monoterpenes, were detected by GC-O. According to the quantitative results, 29 aroma compounds were important, which indicated that their odor activity values (OAVs) were ≥1. On the basis of the GC-O results and OAVs of these volatile compounds, 22 odor-active compounds were mixed to simulate successfully the overall aroma of PG mandarin juice. Furthermore, omission experiments confirmed that nonanal, hexanal, linalool, and (R)-(+)-limonene were the key odorants for the overall aroma of PG juice sample and that β-ionone, decanal, γ-terpinene, and methyl butyrate were also important odor-active compounds.