본 연구는 저온살균(60oC, 5-20분)과 대기압플라즈마(5- 20분)를 병용한 고춧가루 중의 E. coli 저감화 및 시너지 효과를 조사하였다. 저온살균 단일처리시 대장균의 불활 성화는 최대 2 log10 CFU/g(=99% 감소) 이상 나타내었으며, 대기압플라즈마 5, 10, 15, 및 20분간 단일처리 하였을 때 각각 0.4, 0.8, 0.9 및 1.4 log10 CFU/g 감소되었다. 저온 살균 및 대기압플라즈마 단독 처리만으로는 만족할 만한 미생물 저감화효과를 얻을 수 없었기에 저온살균 처리 후, 대기압플라즈마를 병용처리 하여 대장균의 불활성화는 1- 6 log10 CFU/g 이상 감소되었다. 그러나, 저온살균과 대기 압플라즈마 병용처리에 따른 관능적 품질 (색, 이취, 맛, 조 직감 및 전체적인 기호도)에 대한 유의적인 차이는 관찰 되지 않았다(P>0.05). 따라서 고춧가루의 미생물학적 안전성 확보를 위해 저온살균과 대기압플라즈마 단독처리보다 이 둘의 병용처리가 E. coli의 확실한 저감화 효과를 유도 하고 식품 고유의 품질특성을 유지하는데 효과적이었음을 본 연구를 통해 확인되었다.

The physicochemical and sensorial properties of fibrous tofu with the addition of different sized defatted soybean flour (DSF) were investigated. Coarse DSF (DSF-150; D50 = 279 μm), fine DSF (DSF-63; D50 = 105 μm), and super-fine DSF (DSF-JM; D50 = 5.0 μm) were prepared via conventional sifting followed by jet-milling with the milling pressure of 7 bars. Tofu was made with the 5% addition of coarse DSF (TDSF-63), fine DSF (TDSF-150), superfine DSF (TDSF-JM), and without DSF (TC). The yields of tofu were slightly decreased as coarse and fine DSF were incorporated while the yield of tofu with super-fine DSF was statistically identical with that of control tofu (p<0.05). Tofu with larger DSF (TDSF-63 and TDSF-150) showed less smoother texture and less pure in color, while tofu with superfine DSF (TDSF-JM) resulted in little changes in physical and organoleptic qualities, which were verified by quantitative descriptive analysis (QDA), texture profile analysis (TPA), and color measurements. Each fibrous tofu samples were prepared by mixing soymilk with 5% of DSF from sifting (150 μm, 63 μm sieve) and jet milling process which mentioned as TDSF-150 (DSF average particle size), TDSF-63 (D50 = 105 μm) and TDSF-JM (D50 = 5 μm), respectively. The fibrous tofus were compared to the normal tofu (TC). TDSF-JM has higher yielded (50.98%) among tofu samples. The moisture content of TC, TDSF-JM, TDSF-150 and TDF-63 were 75.81%, 75.47%, 69.89% and 69.80%, respectively. TDSF-JM and TC were having similar L-a-b index. Texture properties of TDSF-JM were similar with TC. On the other hand, TDSF-150 and TDSF-63 has statistically significant higher hardness value and lower point on springiness and cohesiveness compared with TC. Sensory evaluation with quantitative descriptive analysis (QDA) method shown that hardness, mouth feel and beany flavor intensity were decreased with the decreasing of particle size of DSF.