62 Handbook of herbs and spices
is conducive to fungal growth. Fungal infection, particularly with toxin-producing
fungi like Aspergillus flavus and Aspergillus parasiticus, may result in accumulation
of mycotoxins that pose a significant health risk to consumers (Table 3.2).
The microbial load on common Indian whole and ground spices varies from sample
to sample as shown in Table 3.3 (Sharma et al., 1984, Munasiri et al., 1987). Some
spices may contain potent antibacterial and antifungal principles that are abundant in
certain spices like clove, cinnamon and ajowan (Sharma et al., 1984, 2000). Spices
are frequently infested with insect pests (Padwal-Desai et al., 1987). The insect pests
normally encountered in spices are given in Table 3.5. These include common storage
insects such as cigarette beetle, confused flour beetle, saw-toothed beetle and Indian
meal moth. Insect infestation of spices is a major storage problem. Spices may also
contain a large amount of antioxidants and radioprotective agents (Gautam et al.,
1998). These agents, along with the antibacterial and antifungal compounds, are
primarily responsible for the medicinal and nutraceutical value of spices.
The addition of heavily contaminated spices even at 0.1% level in a prepared or
Ta ble 3.2 Common microorganisms in spices and herbs
Molds Bacteria Pathogenic bacteria
Aspergillus flavus B. subtilus B. cereus
A. niger B. lichniformis Clostridum perfringens
A. fumigatus B. megaterium E. coli
A. glaucus B. pumilus Salmonella sp.
A. tamarii B. brevis
A. terreus B. polymyxa
A. versicolor B. stearothermophilus
Absidia sp. B. firmis
Mucor sp. S. faecalis
Penicillium
Rhizopus sp.
102 –10^6103 –10^8
Ta ble 3.3 Total bacterial and spore counts in pre-packed ground spices
Spices Total bacteria Total bacterial spore Total fungal spores
CFU/g
Pepper 3 ¥ 106 2 ¥ 106 5 ¥ 102
Chili 4 ¥ 106 2 ¥ 106 6 ¥ 105
Turmeric 1 ¥ 106 8 ¥ 105 1 ¥ 103
Coriander 2 ¥ 105 2 ¥ 105 2 ¥ 103
Ta ble 3.4 Frequency of occurrence of coliforms and E.coli in spices
Range Coliforms E. coli
Samples % Samples %10–10^231142210
102 –10^3219104
103 –10^420942