4
2.2 Tempe
Tempe is a product made from fermented soybean with Rhizopus spp. mould having compact solid form, grey-white color, and specific aroma of tempe
BSN 2009. The main mold used for the preparation of tempe in Indonesia is Rhizopus oligosporus Feng 2006. More strains identified in tempe, including
Rhizopus formosaensis and Rhizopus oryzae Babu et al. 2009. Various microorganisms, including filamentous fungi, yeasts and bacteria, are found in the
traditional tempe. The growth of lactic acid bacteria LAB, coexisting with R. oligosporus, is performed to improve the safety and could inhibit the growth of
pathogenic bacteria Ashenafi and Busse 1991, Feng et al. 2005. Table 2 shows the requirements of tempe quality regulated by National Standardization Agency
of Indonesia BSN.
Table 2 Requirements of tempe quality based on Indonesian national standard SNI 3144:2009.
Parameters Unit
Requirements Conditions
Aroma Color
Taste -
- -
normal, specific normal
normal
Moisture ww max. 65
Ash ww max. 1.5
Lipid ww min. 10
Protein N × 6.25 ww min. 16
Crude fiber ww min. 2.5
Metal poisoning Cd
Pb Sn
Hg As
mgkg mgkg
mgkg mgkg
mgkg max. 0.2
max. 0.25 max. 40.0
max. 0.03 max. 0.25
Microorganisms Coliform
Salmonnella MPNg
- max. 10
negative25 g
Tempe is made by soaking soybeans in water, removal of the seed coat, boiling the cotelydons, cooling, inoculating them with pure or traditional mixture
of starters, and incubating as a solid bed at 25-30
o
C for 24-72 h Nout and Kiers 2005. During fungal fermentation the enzymes degrades some substrates leading
to an increase of free amino acids, water-soluble nitrogen compounds, free fatty acids, and the development of specific flavor
Jeleń et al. 2013. Anti nutritional factors, such as trypsin inhibitors, tannin, and phytic acids, were also leached out
during cooking, dehulling, and fermentation. Besides, tempe processing eliminated almost stachyose, the most flatulent oligosaccharide in soybean
Egounlety and Aworh 2003.