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Comminuted and gelled, fat-containing meat products such as frankfurters and luncheon meats are commercially processed by heating relatively slowly (for up to 2 h or more) to an endpoint of about 70 °C prior to cooling. This study compared such a slow, ramp heating regime (0.5 °C/min), terminated at 70 °C, to rapid, square-wave cooking (one step: rapid 100 °C/min heating to 70 °C endpoint, plus isothermal holding prior to cooling, or two-step: rapid heating to 50 °C, holding, then rapid heating to 70 °C plus holding prior to cooling) on meat batter gel properties (fracture and small strain rheology, microstructure, cook loss, and expressible water). The results indicated that a rapid cooking process, with its inherent advantages of reduced process time, lower equipment footprint, and more efficient use of energy, can produce a product nearly equivalent in textural properties and cook yield to one processed by traditional smokehouse cooking when the cook value of the processes is similar and an intermediate (near 50 °C) holding step is included (two-step rapid heating). One-step rapid heating negatively affected gel structural homogeneity and water/fat holding properties of fat-containing gels.

The effect of different preparations on the functional properties of peanut protein concentrates was studied. Peanut protein concentrates were isolated from defatted peanut flour by isoelectric precipitation, alcohol precipitation, isoelectric precipitation combined with alcohol precipitation, alkali solution with isoelectric precipitation and their functional properties (protein solubility, water holding/oil binding capacity, emulsifying capacity and stability, foaming capacity and rheology) were evaluated. The results showed that the protein solubility, foaming capacity and stability of protein prepared by alkali solution with isoelectric precipitation were the best of all the peanut protein products. But the protein prepared by alcohol precipitation had better water holding/oil binding capacity, which was significantly different from other protein products. The emulsifying stability of protein concentrate prepared by different methods was significantly lower than that of defatted protein flour. The protein prepared by isoelectric precipitation and isoelectric precipitation combined with alcohol precipitation had better gel properties which indicated that they were a potential food ingredient.

Colour distribution of turkey breast meat was evaluated in different flocks during the year to assess the frequency of the pale soft exudative (PSE) problem. The pH, water-holding capacity, cooking loss, and texture of selected samples were also evaluated. Significant correlations (P ≤ 0.05) were found between ‘L’ value and the other parameters, indicating that a colour measurement could be used, on a commercial scale, to assess PSE conditions in turkey breast meat. Overall, mean L value was the highest during the summer (P ≤ 0.05), lowest during the winter, and intermediate during the spring and autumn. Colour measuring time (3 vs 24 h) post mortem had an effect on the measured L value, especially at the low range (L value < 45). The approach for selecting an appropriate cut-off L value, for industrial purposes, by targeting a certain water-holding capacity level is also discussed.

The combined effect of pre-heating temperature (70 °–90 °C) and Ca2+ level (10–120 mM) on Ca2+-induced gelation of whey protein isolates at room temperature was investigated. High pre-heating temperature produced clearer gels than low temperature, and high [CaCl2] produced opaque gels. When protein suspensions were pre-heated to 70 °C (for 30 min), only the gel's clarity was affected by [CaCl2]. Fracture and water holding properties were affected by [CaCl2] only at pre-heat treatment ≥ 80 °C. High gel strength (determined as fracture force and work required to break the gel) was obtained when protein suspensions were pre-heated at high temperature and dialysed against high [CaC12]. High pre-heating temperature resulted in high water holding capacity and gel extensibility (after compression), whereas [CaC12] only affected gel extensibility but not water holding capacity.