Department of Food Science and Technology, Faculty of Agriculture, Urmia University, Urmia, Iran.
Department of Food Science and Technology, Faculty of Agriculture, Urmia University, Urmia, Iran.
Int J Biol Macromol. 2022 Mar 1;200:87-98. doi: 10.1016/j.ijbiomac.2021.12.188. Epub 2022 Jan 5.
A new intelligent pH-sensitive colorimetric label was fabricated by immobilizing Ixiolirion tataricum anthocyanins (ITA) into biocellulose (bacterial nanocellulose; BNC) film and was then studied to determine how it can be used as a label for monitoring freshness/spoilage of shrimp during storage at 4 °C. The formation of new interactions between ITA and BNC film and disruption of crystalline structure of BNC after anthocyanins immobilization were approved by FT-IR and XRD analyses, respectively. According to FE-SEM observations, the porosity of the BNC network decreased after ITA incorporation. The fabricated BNC-ITA label showed a distinct color change from violet to green over the pH range of 4-12. The pH, total volatile basic nitrogen (TVB-N), total psychrophiles count (TPC), and the quantity of biogenic amines (histamine, cadaverine, putrescine, and tyramine) in the shrimp samples and their correlation with color changes on the label were measured over a 4-day storage period. Consistent with changes in levels of TVB-N, TPC, pH, and biogenic amines, a visually distinguishable color change occurred on the BNC-ITA label as blue (fresh), dark green (medium fresh), and kelly green (spoiled). This research showed that ITA as a novel pH-sensitive dye is a promising candidate for developing pH labels for seafood intelligent packaging.
一种新型的智能 pH 敏感比色标签通过将黄花狸藻花色苷（ITA）固定在纤维素（细菌纳米纤维素；BNC）薄膜中而制备，并研究了其如何用作标签，以监测在 4°C 下储存过程中虾的新鲜度/变质情况。FT-IR 和 XRD 分析分别证实了 ITA 与 BNC 薄膜之间形成新的相互作用以及固定花色苷后 BNC 结晶结构的破坏。根据 FE-SEM 观察，ITA 掺入后 BNC 网络的孔隙率降低。所制备的 BNC-ITA 标签在 pH 值为 4-12 的范围内从紫色变为绿色，颜色发生明显变化。在 4 天的储存期内，测量了虾样品中的 pH 值、总挥发性碱性氮（TVB-N）、总嗜冷菌计数（TPC）和生物胺（组胺、尸胺、腐胺和酪胺）的含量及其与标签颜色变化的相关性。与 TVB-N、TPC、pH 值和生物胺水平的变化一致，BNC-ITA 标签上发生了可视觉区分的颜色变化，从蓝色（新鲜）、深绿色（中等新鲜）到深绿色（变质）。这项研究表明，ITA 作为一种新型的 pH 敏感染料，是开发海鲜智能包装用 pH 标签的有前途的候选物。
