Instituto Tecnológico Agroalimentario de Extremadura (INTAEX) (Technological Agri-Food Institute), Badajoz, Spain.
J Food Sci. 2012 Aug;77(8):C866-73. doi: 10.1111/j.1750-3841.2012.02799.x. Epub 2012 Jul 18.
The application of hydrostatic high pressure on a "Songold" plum purée was assessed in comparison with heat pasteurization. To simulate industrial conditions, one-half of the total purée was manufactured with a pretreatment of thermal blanching (TB) and the other half without it (nonthermally blanched, NTB). Changes after thermal treatment and high-pressure processing (HPP: 400, 600 MPa) and after 20 d of refrigerated storage were evaluated. HPP maintained the microbial stability of the purées until the end of the storage period. Polyphenol oxidase activity was lower in TB purées than NTB purées. No treatment was completely effective to stop the enzyme activity, although a significant reduction was reached. Thermally treated purées showed more intense color changes after processing and storage than HP-treated purées. After processing, high-pressure (HP) purées treated at 600 MPa (TB and NTB) increased the extractability of carotenoids compared with initial untreated purée. Nevertheless, at the end of the storage, the highest carotenoid content was found in the TB purée treated at 400 MPa. After processing, total polyphenol levels were similar in all purées. TB and 600 MPa processing was more effective in the maintenance of the polyphenols than the other purées. TB increased the level of antioxidants after storage, compared to NTB purées. A previous TB step is necessary to inactivate browning enzymes before HPP to maintain the levels of bioactive compounds. HPP of plum purée could be a suitable alternative to traditional thermal processing, but more studies are necessary to ensure a major inactivation of polyphenol oxidase.
High-pressure processing is one of the most successful technologies to obtain high-quality fruit purées without appreciable losses in taste, flavor, color, and nutritive value. However, for the introduction of a new technology, some advantages compared to the traditional thermal treatment need to be emphasized. The application of this technology could be reduced due to resistance of certain enzymes to pressurization. For this reason, in some cases the application of a previous thermal blanching can be necessary at industrial level. However, this can reduce the advantages of HPP application. This paper provides interesting information about the storage stability of plum purées after high-pressure treatments and assesses the need for applying heat pretreatments.
将静水高压应用于“Songold”李泥与热巴氏杀菌进行了比较评估。为了模拟工业条件，将一半的总李泥进行了热烫预处理（TB），另一半则没有（非热烫，NTB）。评估了热处理和高压处理（HPP：400、600 MPa）以及冷藏 20 天后的变化。HPP 保持了果泥的微生物稳定性，直到储存期结束。与 NTB 果泥相比，TB 果泥中的多酚氧化酶活性较低。没有一种处理方法能完全有效地阻止酶的活性，尽管活性显著降低。经热处理的果泥在加工和储存后比 HP 处理的果泥颜色变化更剧烈。加工后，与初始未处理的果泥相比，600 MPa（TB 和 NTB）高压处理的高压（HP）果泥增加了类胡萝卜素的提取率。然而，在储存期末，TB 处理的 400 MPa 果泥中类胡萝卜素含量最高。加工后，所有果泥中的总多酚含量相似。TB 和 600 MPa 处理在保持多酚方面比其他果泥更有效。与 NTB 果泥相比，TB 处理在储存后增加了抗氧化剂的水平。在 HPP 之前，TB 步骤对于失活褐变酶是必要的，以保持生物活性化合物的水平。HPP 处理李泥可能是传统热加工的替代方法，但需要进行更多的研究，以确保多酚氧化酶的有效失活。
高压处理是获得高质量果泥而不明显损失口感、风味、颜色和营养价值的最成功技术之一。然而，为了引入一项新技术，需要强调其与传统热处理相比的一些优势。由于某些酶对加压的抵抗力，该技术的应用可能会减少。出于这个原因，在某些情况下，工业水平上可能需要应用先前的热烫处理。然而，这会降低 HPP 应用的优势。本文提供了关于高压处理后李泥储存稳定性的有趣信息，并评估了应用热预处理的必要性。
