Impact of Pretreatment and Drying Factors on Chemical and Biochemical Attributes of Moroccan Thompson Seedless Grapes

Table 5

Evaluation of quality attribute between treated and untreated grape samples dried under optimal conditions (5 min blanching in a solution of NaOH at 1% concentration; ; ).

Antibrowning agent		Physicochemical and biochemical characteristic
Agent	Concentration	Water content (%)		Rehydration rate	Browning rate	TPC (mg GAE/100 g DF)	TFC (mg Qeq/100 g DW)	HMF (mg/100 g DW)	SO2 content (mg of S02/kg DF)	PPO residual activity (%)
Control	0%	^a	^a		^a	^a	^a	^a	nd	^a
Na2S2O5	5%	^b	^b		^c	^b	^c	^b	^a	^c
Sig

Na₂S₂O₅: sodium metabisulfite; : color intensity change; : chromaticity; TPC: total phenol content; TFC: total flavonoid content; HMF: hydroxymethylfurfural; nd: not detected; SO₂: sulfur dioxide content; PPO: polyphenol oxidase; signification levels: , , and . Columns with the same letter belong to the same group.