Phytochemicals preservation in strawberry as affected by pH modulation

作者：Oliveira Ana; Gomes Maria Helena; Alexandre Elisabete M C; Pocas Fatima; Almeida Domingos P F; Pintado Manuela^*

来源：Food Chemistry, 2015, 170: 74-83.

DOI：10.1016/j.foodchem.2014.07.156

• Anthocyanins
• Fragaria x ananassa
• Puree processing
• pH modulation
• Kinetic

Strawberries purees are incorporated in foods and subjected to pH modulation according to the expected final food matrix. The effect of pH on strawberry polyphenols stored at 4 and 23 degrees C for 90 days was evaluated.
Total antioxidant activity and total phenolics content were only affected by time according to a first order model. The pH 4.5 induced higher decrease in (-)-epigallocatechin gallate (71% and 79%) and quercetin-3-glucoside (29% and 36%), for both storage temperatures. For pH 2.5 and 3.0, ellagic acid increased 84% for 4 degrees C. and 185% for 23 degrees C.
Anthocyanins concentration changes along storage were well described by first order model. The pH value of 2.5 presented the lower kinetic constant rate where cyanidin-3-glucoside, pelargonidin-3-glucoside and pelargonidin-3-rutinoside had a k = 0.04, 0.05 and 0.03 day(-1).
Lower storage temperature (4 degrees C) and lower pH (2.5) were the best condition for the preservation of polyphenols in pasteurized strawberry during a 90-day storage period.

• 出版日期2015-3-1