Dataset for "Novel Colour-Based, Prototype Indicator for Use in High- Pressure Processing (HPP)"

Data set to accompany paper "Novel Colour-Based, Prototype Indicator for Use in High- Pressure Processing (HPP)". Abstract for paper: The preparation and testing of a colour-based prototype indicator for high-pressure processing (HPP) are described. The indicator is a layered structure comprising a pressed disc of a mixture of silica gel, which has been previously loaded with a set wt% of acidified water, and polytetrafluoroethylene, PTFE, powders, a water-permeable barrier layer, and a Congo-Red-based pH indicator layer, all vacuum-sealed in a water impermeable plastic film. The value of the wt% is calculated from the ratio of the mass of acidified water added to the mass of originally dry silica gel. The high pressures associated with HPP drive the release of the acidified water from the silica gel and its subsequent transport through the water-permeable barrier layer to the pH indicator, thereby producing a striking red-to-blue colour change. The response of the HPP indicator can be tuned to different HPP conditions by varying the wt% of acidified water used to load the silica gel powder. Indicators, with 61, 63, and 65 wt% acidified water loaded silica gel, are prepared and found to require, respectively, the application of at least, 600, 400, and 300 MPa pressure for 3 min to effect a change colour. To our knowledge, this is the first reported example of a prototype HPP indicator that can be tuned to respond to the very different pressure and time conditions used in HPP to sterilise such very different products as milk, apple and orange juice, and aloe vera gel.

本数据集配套论文《用于高压加工（High-Pressure Processing, HPP）的新型颜色基原型指示器》。论文摘要如下：本文详述了一款用于高压加工（HPP）的颜色基原型指示器的制备与测试流程。该指示器为分层结构，由以下组件组成：预先负载了固定质量百分比（wt%）酸化水的硅胶（silica gel）与聚四氟乙烯（polytetrafluoroethylene, PTFE）粉末混合压制圆盘、透水阻隔层以及刚果红基pH指示剂层，所有组件均经真空密封于不透水塑料薄膜内。此处的质量百分比（wt%）由添加的酸化水质量与初始干燥硅胶的质量之比计算得到。高压加工（HPP）过程中的高压环境会促使酸化水从硅胶中释放，并经透水阻隔层输送至pH指示剂层，进而引发醒目的红色至蓝色颜色变化。通过调整负载于硅胶粉末的酸化水质量百分比（wt%），可将该HPP指示器的响应特性调节至适配不同的HPP工艺条件。研究人员制备了分别负载61%、63%及65%酸化水的硅胶基指示器，测试结果显示，其分别需要至少600、400及300 MPa的压力持续3分钟，方可触发颜色变化。据我们所知，这是首款可调节响应参数的HPP原型指示器，能够适配高压加工中对牛奶、苹果汁、橙汁及芦荟凝胶等各类迥异产品进行灭菌时所采用的多样压力与时间条件。