Development of the fermented instant Chinese noodle using lactobacilli

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Development of the fermented instant Chinese noodle using lactobacilli
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     Yuuki Sawatari , Yasuyuki Suzuki, Akihiro Hanaoka , Katsuichi Saito , Akihiro
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                  Yamauchi , Sanae Okada , Kozo Asano and Atsushi Yokota
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     Laboratory of Microbial Resources and Ecology, and Laboratory of Applied Microbiology,
                      Graduate School of Agriculture, Hokkaido University
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                                               Toyo Suisan Kaisha, Ltd.
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          Department of Upland Agriculture Research, National Agricultural Research Center for
                                          Hokkaido Region
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                                     NRIC, Tokyo University of Agriculture

[Aim] To develop the valued-added instant chinese noodle using the strong wheat flour from
KITANOKAORI harvested in Hokkaido Japan, we are investigating to develop the fermented
instant chinese noodle using lactobacilli. The dough of the instant chinese noodle is normally
alkaline, because a KANSUI (alkaline salts) is added to strengthen its specific properties
(texture, flavor and color). Generally, in lactic acid bacteria, aerococcii, enterococcii and
tetragenococcii are known to grow on alkaline medium. However, the growth of lactobacilli
under the alkaline conditions is not well documented. Thus, many lactobacilli were screened
for their abilities to ferment the dough of the instant chinese noodle.
[Methods] Culture: The following 70 strains of 13 species of lactobacilli were obtained
from JCM, AHU and NRIC: Lactobacillus brevis, Lb. casei subsp. csei, Lb. curvatus, Lb.
fermentum, Lb. helveticus, Lb. hilgardii, Lb. delbrueckii subsp. lactis, Lb. mali, Lb.
paracasei subsp. paracasei, Lb. paracasei subsp. tolerans, Lb. pentosus, Lb. plantarum,
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Lb. sakei. The lactobacilli were cultured at 30 or 37 C in 1/2 MRS broth under anaerobic
conditions until late exponential phase. The cells were harvested by centrifugation, washed,
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and resuspended in sterilized deionized water (SDW) at the final concentration of about 10
viable cells/ml. Noodle fermentation test: The following ingredients for instant chinese
noodle were mixed and sheeted: 30 g of strong flour, 5 ml of SDW, 0.6 g of NaCl, 0.04 g of
Na2CO3, 0.06 g of K2CO3 and 6 ml of cells suspension. The sheets were put into plastic bags
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and incubated at 30 C for 24 hr. Analysis: The 2 g of noodle sheets were added in 8 ml of
SDW and homogenized. The homogenized samples were centrifuged and supernatants
obtained were used as the samples for pH measurement and organic acid analysis by HPLC.
The homogenized samples were serially diluted with saline and mixed in melted 1/2 MRS agar
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with CaCO3. After 2 days of incubation at 30 C under anaerobic conditions, the number of the
colonies with clear zone was counted. Sensory test: After fermentation of the noodle sheets,
the instant noodles were prepared in the laboratory of Toyo Suisan Kaisha, Ltd. The sensory
test of the prepared instant noodle was done to evaluate the taste, color, texture and smell. To
evaluate stability of the fermented instant chinese noodles, they were stored in the oven at
  o

60 C for 20 days to oxidize the noodle lipids. The treated samples were sniffed to check
off-flavor.
[Results] Screening of the fermentation strains: From 70 strains of lactobaciili, 3 strains
of Lactobacillus pentosus and 6 strains of Lb. plantarum were found to decrease pH of the
noodle sheets below 5.5 within 24 hr of fermentation with good reproducibility. All of these
strains were plant origin and isolated from salty foods (pickles or fermented tea leaves
“miang”). Interestingly, the rest of the strains were not able to ferment noodle sheets at all. Lb.
plantarum NRIC 1832 was selected as the best strain because it shows the fastest pH decrease
of the noodle sheets. Analysis of noodle fermentation: The pH of the noodle sheets
fermented with Lb. plantarum NRIC 1832 decreased from initial 8.8 down to 6.6, 5.7 and 4.0
after 6, 12, 24 hr, respectively. The lactic acid concentration of the noodle sheets reached 8
mg/g noodle sheet after 24 hr of fermentation. The number of viable LAB cells in noodle
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sheets was 4.5 x 10 , 6.2 x 10 and 8.4 x 10 CFU/ g noodle sheet at the start of fermentation,
after 12 and 24 hr of fermentation, respectively. Sensory test: The short-term fermentation (1
hr) with Lb. plantarum NRIC 1832 gave the elasticity, favorable sour taste to the instant
chinese noodle. However, long-term fermentation (24 hr) resulted in the deterioration in
rheology and in strong sour taste. The noodle color also changed from yellow to white. The
off-flavor was detected from the long-term-fermentation sample after the storage, while that
from short-term-fermentation sample was negligible. From these results the possibility of the
development of fermented instant chinese noodle with lactic acid bacteria has been
demonstrated.
[Acknowledgement] This work was conducted under the framework of the Research and
Development Program for New Bio-industry Initiatives.

				
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posted:5/18/2011
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