The effects of water and glass transition on the hydrolysis of sucrose by invertase in noncrystalline carbohydrate systems were investigated. Maltodextrin/sucrose (2:1) and maltodextrin/lactose/sucrose (1:1:1) were dissolved in distilled water. Invertase (10 mg/17.2 g) was added. Amorphous samples were produced by freeze-drying the solutions. Sorption isotherms were determined gravimetrically at 24 degrees C over the 0.113-0.763 aw, and over 0.239-0.764 aw, the glass transition, Tg was determined using differential scanning calorimetry (DSC). DSC and water sorption results suggested that samples remained noncrystalline. Sucrose inversion was analysed by monitoring glucose content during storage. Sucrose hydrolysis occurred at significant rates at 0.662 and 0.764 aw. The rate increase was not related to the apparent glass transition of the systems.

A novel method of hydrofluidisation food freezing is numerically investigated in this paper. This technique is based on freezing small food products in a liquid medium under highly turbulent flow conditions when the heat transfer coefficient is higher than 1 000 W⋅m⁻²⋅K⁻¹, which depends on the operating and flow conditions. A numerical model was developed to characterise the freezing process in terms of the heat transfer and diffusion of liquid solution components into the food product. The study investigates the freezing process of spherical samples in binary solutions of ethanol (30%) and glycerol (40%) and ternary solution of ethanol and glucose (15%/25%). The developed model was employed to determine the concentration of the liquid solution in food samples and to quantify the effect of sample size, heat transfer coefficient, solution temperature and concentration on the process. The food sample size varied from 5 to 30 mm, and the heat transfer coefficients varied from 1 000 to 4 000 W⋅ m⁻²⋅ K⁻¹. The results confirm that a freezing time of 15 min for 30 mm diameter samples or less than 1 min for 5 mm diameter samples can be achieved with the hydrofluidisation method. The solution uptake was influenced by the solution type, sample size and process parameters and varied from 8.9 to 35 g of solute per kg of product for ethanol-glucose and glycerol solutions, respectively. This paper quantifies the advantages and possible limitations of hydrofluidisation, which has not yet been entirely studied, especially in terms of the mass absorption of different solutes.

The gasification of some selected components of food wastes using H₂O₂ as the oxidant and in the presence of NaOH has been investigated under subcritical water conditions. Hydrogen production was enhanced when both NaOH and H₂O₂ were used compared to when either NaOH or H₂O₂ alone was used or in their absence. Results indicated that the H₂O₂ acted to partially oxidize the samples while NaOH significantly increased hydrogen gas yields by promoting the water-gas shift reaction with subsequent CO₂ capture. In the presence of NaOH, the main components were Na₂CO₃, CH₃COONa and CH₃COONa·3H₂O. Char and tar production were suppressed in the presence of NaOH.

The objective of this study was to evaluate the effects of a 6, 12, 18, 24, or 30h transport period on the physiology and reproductive success of breeding age gilts, simulating transport of breeding gilts from one farm to a commercial breeding herd. Fifty gilts were allocated to one of five transport (TRANS) treatment groups; transported for 6, 12, 18, 24, or 30h. Fifteen gilts were allocated to one of five control (CON) treatments; gilts remained in their home pen for 6, 12, 18, 24, or 30h. Every 6h, gilts from one TRANS treatment were removed from the trailer. Blood samples were collected from gilts and their respective controls before and after transport. Gilts were then bred after puberty. The granulocyte to lymphocyte ratio (P<0.05) and cortisol concentrations (P<0.07) were greater in TRANS compared with CON gilts after a 6 and 12h transport period. Albumin concentrations were greater (P<0.001) in transported gilts after an 18 and 30h transport period compared with CON gilts. Blood urea nitrogen, glucose, and total protein concentrations were greater (P<0.05) in transported gilts compared with controls, regardless of the transport period. Reproductive performance measures did not differ (P>0.05) among treatments regardless of the length of transport duration. These data indicate that gilts transported for a period of up to 30h experienced initial acute stress during the first 6 to 12h and changes in water homeostasis throughout the 30h journey due to dehydration, food deprivation, and transport, however reproductive measures suggest that the long-term homeostasis of the gilts in this study were not significantly compromised. Transport of breeding gilts induced acute, transient stress but did not negatively impact reproductive performance. Interestingly, gilts were more at risk of physiological perturbations when transported 6h or less than 12 to 30h.