The effects of thermal processing and β-cyclodextrin on extractable polyphenols in mulberry juice-enriched dried minced pork slices

Abstract

To explore strategies for improving polyphenols retention in hot processed food, the effects of heat treatment time-temperature combinations and β-cyclodextrin addition on the extractable polyphenols in mulberry juice-enriched dried minced pork slices were studied. The results indicated that phenolic compounds underwent the greatest losses with processing conditions of drying at high temperature × short time followed by baking at low temperature × long time. A procedure of drying for 10 h at 40 °C followed by baking for 3 min at 150 °C was recommended for slice preparation on the basis of the highest retention rates of phenols (54.84% polyphenols, 39.1% flavonoids, and 59.62% anthocyanins). The total polyphenol content, total flavonoid content, total anthocyanin content, ABTS▪+ scavenging ability, ferric-reducing antioxidant power, and oxygen radical-absorbance capacity of the product could be further enhanced by adding 1% β-cyclodextrin. Four phenolic acids, three flavonoids, and two anthocyanins were detected in the products. Most phenols remained stable during storage except for cryptochlorogenic acid, caffeic acid and quercetin; β-cyclodextrin did not effectively prevent the degradation of the latter two. Overall, the results suggest that optimizing the heat treatment process as well as adding β-cyclodextrin may be promising strategies for improving the stability of mulberry polyphenols.