Calorific losses in maize in relation to colonisation by isolates of Aspergillus ochraceus under different environmental conditions

Citation
Aj. Ramos et al., Calorific losses in maize in relation to colonisation by isolates of Aspergillus ochraceus under different environmental conditions, J CEREAL SC, 29(2), 1999, pp. 177-183
Citations number
28
Categorie Soggetti
Food Science/Nutrition
Journal title
JOURNAL OF CEREAL SCIENCE
ISSN journal
07335210 → ACNP
Volume
29
Issue
2
Year of publication
1999
Pages
177 - 183
Database
ISI
SICI code
0733-5210(199903)29:2<177:CLIMIR>2.0.ZU;2-5
Abstract
The effect of water activity (a(w), 0.85-0.95), temperature (15-30 degrees C) and incubation period (2-4 weeks) on growth and calorific losses in rela tion to colonisation by three mycotoxigenic isolates of Aspergillus ochrace us was studied on maize-based substrates. The calorific losses (kJ) of maiz e flour due to fungal growth in relation to temperature and a(w) were quant ified and found to be maximal at 20-30 degrees C (10.52-16.18%, after 4 wee ks at 0.95 a(w)), with only slight losses at 0.85 a(w) (0-7.14%), at both 1 5 and 20 degrees C. This suggests that growth of mycotoxigenic Aspergillus spp. can significantly contribute to nutritional losses of this staple agri cultural food. Calorific values correlated inversely with fungal biomass, w ith the latter being greatest at 0.95 a(w) after both two and four;weeks, a nd maximal at 30 degrees C. Most of the single, two-, three- and four-way i nteractions of a(w), temperature, time and isolate had a statistically sign ificant (p<0.01) influence on calorific losses and fungal biomass. (C) 1999 Academic Press.