Effects of Vacuum Container on the Storability of Leftover Tofu

진공용기를 이용한 포장두부의 개봉 후 저장성 연장

  • Published : 2009.02.28

Abstract

Commercial tofu was cut and re-packed in a vacuum container, an airtight container and an open tofu tray in an effort to assess the effects of vacuum containers on the shelf life of leftover tofu. The re-packed tofu were stored at $5^{\circ}C$ and $25^{\circ}C$ for the enumeration of total bacteria and coliforms. We also measured changes in color, pH, and opacity. The vacuum retarded the bacterial growth under $10^5$ CFU/mL for up to 12 days at $5^{\circ}C$. The color of the tofu was unaffected by the container type at both storage temperatures, whereas the pH and opacity of the immersion solution were altered less profoundly by storage in the vacuum container at $5^{\circ}C$. However, we noted no significant differences in bacterial growths, pH, and opacity among container types at $25^{\circ}C$. The results of this study showed that the usage of vacuum containers may be a favorable method for the preservation of tofu under refrigerated conditions.

본 연구는 개봉 후 남은 두부의 보관에 이용되는 용기 및 저장방법에 따른 두부의 저장성을 평가하고자, 진공용기, 밀폐용기, 그리고 두부제조사의 두부 포장용 트레이를 이용하였다. 냉장온도($5^{\circ}C$)에서는 진공용기를 적용하였을 때 미생물 생장을 일부 억제한 반면, 상온($25^{\circ}C$)에서는 용기간 유의적 차이가 없었다. 이는 온도 상승에 의한 미생물 생육이 진공을 적용함으로 억제되기는 어렵다는 것을 보여준다. 두부의 색도 변화는 온도와 저장기간에 따른 차이가 거의 없어 침지에 의해 색변화가 억제되는 것으로 사료된다. $5^{\circ}C$에 저장한 두부 침지액의 pH는 진공용기에서는 15일째까지 초기값을 유지하였으며 밀폐용기 및 트레이는 각각 12일 및 9일 이후 감소하여 진공용기와 차이를 보였다. 상온 저장에서는 12시간 이후 침지액의 pH 및 탁도 변화가 모든 용기에서 급격히 일어나 두부의 보관수명이 12시간을 넘지 못하였다.

Keywords

References

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