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Volatile compounds were quantified in the headspace of Indian, Vietnamese and Brazilian cashews, both raw and during roasting by Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS). Raw cashews were oil roasted for 3 to 9 min at 143 ¿¿¿¿C and color and volatiles measured. An excellent correlation, following a pseudo-first order reaction, was found between L value and roasting time; darkness increases as roasting time increases. The optimum roasting time was 6, 8 and 9 min for Vietnamese, Indian and Brazilian cashews, respectively. Raw cashews had lower concentrations of volatiles than roasted cashews. Most volatiles significantly increased in concentration during roasting of Brazilian, Indian and Vietnamese cashews. Brazilian cashews had significantly higher levels of most volatiles than Indian and Vietnamese cashews. Of the volatiles, methylbutanal, 2-methylpropanal and acetaldehyde were at the highest concentration in roasted cashews. The Maillard reaction contributed to the formation of the most of the volatiles in the cashews from the three countries.Raw pasteurized almonds were roasted in a microwave for 1 to 3 min, in an oven at 177 ¿¿¿¿C for 5, 10, 15, and 20 min; and at 135 and 163 ¿¿¿¿C for 20 min, and in oil at 135, 163, and 177 ¿¿¿¿C for 5 min and 177 ¿¿¿¿C for 10 min. Volatile compounds were quantified in the headspace of ground almonds, both raw and roasted, by Selected Ion Flow Tube-Mass Spectrometry (SIFT-MS). Strong correlations were found between L value, chroma, and 5-hydroxymethyl furfural (HMF). Raw almonds had lower concentrations of most volatiles than roasted almonds. Conditions that produced color equivalent to the commercial samples were 2 min in the microwave, 5 min at 177 ¿¿¿¿C in the oven, and 5 min at 135 ¿¿¿¿C in oil. Microwave heating produced higher levels of most volatiles than oven and oil roasting at commercial color. Sensory evaluation indicated microwave-roasted almonds had the strongest aroma and were the most preferred. Oil-roasted almonds showed significantly lower levels of the volatiles than other methods. The Maillard reaction contributed to the formation of more of the total volatiles in almonds than the lipid oxidation reaction.Ten Ohio and Indiana honey samples from star thistle, blueberry, clover, cranberry, wildflower, and an unknown source were collected. The headspace of these honeys was analyzed by selected ion flow tube mass spectrometry (SIFT-MS) and soft independent modeling of class analogy (SIMCA). Ohio honeys from star thistle, blueberry, and clover were similar to each other in volatile composition, while Ohio wildflower honey was different. Indiana honeys from star thistle, blueberry, and wildflower were different from each other in volatile composition while clover and cranberry honeys were similar. Honeys from Ohio and Indiana with the same floral origins were different in volatile composition. Furfural, 1-octen-3-ol, butanoic and pentanoic acids were the volatiles with the highest discriminating power between types of floral honey. The highest concentration of volatile compounds was in Indiana wildflower honey followed by Ohio wildflower honey while the lowest concentration of volatile compounds was observed in Ohio clover honey followed by Indiana clover honey.

A bio-refinery is a facility that converts renewable bio-resources into value-added chemicals and products. In this context of a bio-refinery, the production of the carbochemicals such as HMF, furfural and organic acids illustrate that multiple products can be produced from a renewable source such as lignocellulosic biomass (switchgrass). Traditionally, carbochemicals such as furfural and HMF are produced using inorganic acids such as H2SO4, HCL, and H3PO4. The use of such acids requires the application of high cost materials of construction such as Hastelloy-C, titanium etc. The objective of this study is to develop a semi-continuous process for the conversion of switchgrass to carbochemicals such as HMF, furfural and organic acids. Moreover, the application of water as a green reaction medium and the utilization of carbonated water as a "green catalyst" were studied in this research. For the purpose of this study, we constructed a semi-continuous flow apparatus using three high precision Isco syringe pumps and a constant temperature oven to allow carbonation of the water over a range of temperatures and pressure to reactively pretreat switchgrass. Carbochemicals (furan-based aldehydes) and acids that were formed were detected using a Waters HPLC employing a Bio-Rad Aminex HPX-87H column with a PDA (photo diode array) detector at wavelengths range of 210 and 280nm. Oligosaccharides were detected using Dionex HPLC employing Bio-Rad Aminex HPX-87P column using a Shodex RI-101 refractive index detector. The kinetics of the formation and degradation of HMF and furfural were studied using the solver function in Microsoft Excel. Carbonated water clearly showed catalytic activity by increasing the yields of the HMF and furfural at temperatures of 220, 250 and 280°C. The highest catalytic activity was observed for HMF formation in carbonated water with a nine-fold increase in yields over that using neat subcritical water.

Meat is an excellent source of many essential nutrients and makes an important contribution to a balanced diet. Specialty frying has been demonstrated to great effect on fruits and vegetables, but has been used only rarely with animal products and, until now, not at all with beef. In this study, strips of marinated beef were fried and stored in two different packaging materials in order to determine the effects of packaging and storage. The packaging types were polyethylene terephthalate (PET) and aluminium foil laminate. The water vapour transmission rate (WVTR) was slightly higher for PET and it also had a higher oxygen transmission rate (OTR) (14.7 compared to 3.0 cc/m².day). The cooked beef samples were stored at 11°C, 15°C, 25°C, 35°C and 39°C for three, five, 10, 15 and 17 weeks and the samples and oil extracted from the samples were analysed for quality changes. Response surface methodology (RSM) was used to analyse the responses, and the equations generated were also used to predict responses during storage of up to 32 weeks at 15, 20 and 25°C. The integrated force (kg.sec) was the only significantly affected texture parameter but only for the samples stored in PET packaging; there were no significant changes in breaking force (kg), linear distance (kg.sec) and number of peaks for either packaging type. Moisture content and water activity were also only affected after storage in PET packaging. The moisture content in the stored samples increased from the initial moisture content of 4.17% (dry weight basis) but decreased with increasing storage temperature and was dependent on the relative humidity inside the incubators. Water activity increased from 0.19 to 0.33 after storage for 15 weeks at 15°C, and was predicted to increase to 0.55 after 32 weeks of storage. There were significant changes in colour for both packaging types, expressed as total colour change and browning index. Lipid decomposition was evidenced by significant increases in free fatty acids (FFAs) for both packaging types and the Totox value for PET packaging, although these changes were considered to be minor, with FFAs reaching only 4.0 (% oleic acid) during 17 weeks of storage and predicted to increase to over 8% after 32 weeks of storage and the Totox value was not predicted to exceed 32 even after 32 weeks of storage. FFA levels were higher in the oil from the samples stored in aluminium foil laminate packaging. There were no significant changes in the unsaturated fatty acid content but the levels of PUFA, C18:2 and C18:3 fatty acids decreased during 17 weeks of storage, and mean levels were higher in the aluminium foil packaging, indicating less oxidation had occurred. The tocopherol contents decreased significantly from initial concentrations and mean levels were higher in the oil from cooked beef strips stored in aluminium foil laminate packaging, but the response could not be satisfactorily modelled by RSM. The neo-formed contaminants hydroxymethylfurfural (HMF) and sterol oxidation products (SOPs) were also monitored; HMF increased in both packaging types but it was not possible to model the SOPs data as it was too variable. The results of this experiment suggest that fried beef strips can be stored for up to 32 weeks at temperatures from 15-25°C without large changes in quality. Aluminium foil laminate packaging reduced most of the changes that occurred due to its lower OTR and WVTR, but both materials were acceptable. Future research into the shelf-life of fried beef strips should concentrate on the use of antioxidants to reduce oxidative changes, SOPs formation and a sensory analysis to determine the acceptability of the products after storage.