SEASONAL VARIABILITY OF CHEDDAR CHEESE WHEY POWDER: A CASE STUDY

Cheddar whey powder from one plant was evaluated for variations in quality parameters over 12 months. Representative samples were analyzed monthly for microbiological, physicochemical and sensory properties. The seasonal variability in the physicochemical properties was minor. Fall samples were higher in Hunter Lab parameter L* (lightness) and pH but lower in solubility index. Summer samples were high in solubility index and titratable acidity but low in L*. May production was significantly higher in standard plate count (SPC) and free moisture than the rest of the year. February production was significantly lower in SPC and free moisture content. There were no significant differences in aroma and flavor across the seasons. The flavor was generally bland, with the most intense attribute rating 5 on the 15‐point intensity scale. The order of intensity of the most intense attributes was cooked flavor and aroma > sweetness > caramelized flavor and aroma.     

Effect of Colletotrichum acutatum ripe rot on the composition and sensory attributes of Cabernet Sauvignon grapes and wine

Background and Aim:  The impacts of the fungal bunch rot pathogen Colletotrichum acutatum (ripe rot) on grape growing are documented; however, little is known about how the disease affects the resulting wine. This work aimed to investigate how ripe rot affects wine composition and sensory properties.
Methods and Results:  Wine was made using Cabernet Sauvignon grapes grown in the Hastings Valley (NSW). Berries with ripe rot tended to shrivel and acquired a distinctive off flavour and bitterness, described as hessian sack and musty. Wine made from the infected fruit had a higher pH and a higher level of residual sugar, but lower titratable acidity. Volatile acidity in wine made from uninfected fruit was 0.57 g/L, but increased to 0.83 and 1.06 g/L with 1.5 and 3% infection, respectively. Wine made from infected fruit had higher levels of both glycerol and gluconic acid indicative of fungal contamination. Alcohol concentration was also higher in wine made from infected fruit. Sensory analysis indicated that wine made from as low as 3% infected fruit had a similar colour density to control fruit, but a distinctive off-flavour, and browner colour hue.
Conclusions:  As far as we are aware of, this is the first report of a correlation between the level of grape infection by C. acutatum and wine composition in Australia.
Significance of the Study:  These results underline the problems of red grapes infected with C. acutatum . It provides viticulturists and winemakers with information to be considered when assessing grape quality and winemaking process for red wines.     

CORROSION AND WEAR PROPERTIES OF MATERIALS USED FOR MINCED MEAT PRODUCTION

The risk of material degradation is present in minced-meat processing equipment. Corrosion, wear and tribocorrosion properties of commonly used steel materials for such processing equipment are therefore studied in detail. Corrosiveness of minced meat has been evaluated by potentiodynamic measurements. Combined sliding wear and corrosion conditions have been simulated in laboratory using a block-on-ring setup allowing for electrochemical measurements. Detailed information concerning the mechanism of possible material degradation is provided by these results, together with microstructural analysis and thermodynamic considerations. Areas of precaution are stated and new material solutions are suggested.

PRACTICAL APPLICATIONS

The presented results show the importance of investigating both corrosion and wear properties of materials used for processing food under tribocorrosive conditions. In meat mincing, the processing materials need to be wear resistant and at the same time corrosion resistant because of possible aggressiveness of the food product and cleaning procedures. The use of laboratory setups has made it possible to investigate a steel containing vanadium-nitride and carbide phases in respect of both corrosion and wear properties