A New Quality Parameter in Tomato and Tomato Products: Ergosterol

Determination of mold contamination using ergosterol imprinted particles

Ergosterol is a key biochemical marker for fungal mycelial growth. In this study, molecularly ergosterol imprinted particles (Erg-MIPs) were newly synthesized for the selective detection of ergosterol in mold samples. Erg-MIPs were characterized via scanning electron microscopy, swelling studies, and surface area measurements. Maximum selective ergosterol adsorption achieved as 28.50 mg/g Erg-MIP. Selectivity studies showed that Erg-MIPs adsorbed Erg 2.01 and 3.27 times higher than that of cholesterol and stigmasterol, respectively. Erg adsorption from Aspergillus niger was found as 23.87 mg/g. Reusability of Erg-MIPs was studied and decrease in Erg adsorption capacity of the particles was negligible (3%). Erg-MIPs are good affinity materials for the selective Erg detection from food samples, prior to use in food industry.

Patulin, ergosterol and Howard mold count (HMC): Which one is the best quality indicator for tomatoes?

Ergosterol, an important constituent of fungal cell wall, was started to be used as a quality parameter for the tomatoes and derivatives instead of Howard mold count (HMC). In addition, patulin is another important microbiological quality indicator of molds such as Penicillium, Aspergillus, and Byssochlamys. In this study, it is aimed to identify the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which has the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. As the rotten proportion increased, HMC, ergosterol, and patulin values increased. Linear correlations (r) between HMC, ergosterol, patulin, and rotten proportion were calculated as 0.99, 0.99, and 0.98, respectively. In addition, linear correlations between HMC and ergosterol (r = 0.95), HMC and patulin (r = 0.95) and ergosterol and patulin (r = 0.98) were found. In contrast, non-linear correlation between pH, brix and titratable acidity, and the rotten proportion was determined. PRACTICAL APPLICATIONS: The manuscript has provided the relationship between HMC, patulin, and ergosterol in juices produced from the tomatoes which have the surface rotten of 0% (sound), 25%, 50%, 75%, and 100%. Linear correlations between rotten proportions of tomatoes and HMC, ergosterol, patulin and between HMC and ergosterol, HMC and patulin, and ergosterol and patulin were determined in juices produced from rotten tomatoes. Patulin indicated correlation with HMC and ergosterol in juices produced from rotten tomatoes. In addition to HMC and ergosterol, patulin has great potential for the assessment of tomato products as associated with the rotten proportion.

Effects of temperature and packaging types on ergosterol and Howard mold count values of tomato paste during storage

The objective of the present study was to investigate the effects of temperature and packaging on ergosterol and Howard mold count (HMC) changes of tomato paste during storage. The other purpose of this study was to determine whether the measurement of ergosterol stability in tomato paste can be useful for the assessment of microbiological quality of tomato paste as related to the storage temperature (4, 20, 28, or 37°C) and time. Ergosterol analysis was done by using high-performance liquid chromatography. Tomato paste samples were packaged in either aseptic bags or tin boxes and stored at 4, 20, 28, or 37°C for a period of 10 months. The detection limit of ergosterol was 0.1 mg/kg. Measurements showed that packaging and storage temperatures of 28 and 37°C have a considerable influence on ergosterol and HMC changes in the product. The poor precision of the "percentage of discarded fruits" and HMC methods has increased the importance of ergosterol for the microbiological quality evaluation of tomato and tomato products. This article reports the data from what we believe to be the first survey for the influence of storage temperature and packaging material on ergosterol and HMC changes of tomato paste during storage.

Grading of fermented and dried cocoa beans using fungal contamination, ergosterol index and ochratoxin a production

Sixty four samples of cocoa beans replicated in quadruplicates were collected from five warehouses from southwest Nigeria and examined for fungal loads, ergosterol and ochratoxin A The levels of all the variables obtained were further used as indices for cocoa grading into food quality, FoQ (erg < 5 mg/kg; OTA < 1 µg/kg), feed quality, FeQ (erg = 5~10 mg/kg; OTA in the range of 1.1~3.11 µg/kg), Screen for mycotoxin, SFM (erg = 10~20 mg/kg; OTA from 3.12 µg/kg and above) with fuel quality, FuQ having erg > 20 mg/kg and OTA > 6.12 µg/kg. Using these ergosterol indices, 18.75% of the cocoa beans examined was classified with the FoQ, 18.75% with the FuQ while 31.25% was classified with both the FeQ and the SFM, respectively. In conclusion, ergosterol can be used as a rapid index to grade fermented, dried cocoa beans meant for export.