Influence of Pre‐drying treatments on Quality and Safety of Sun‐dried Tomatoes. Part II. Effects of Storage on Nutritional and Sensory Quality of Sun‐dried Tomatoes Pretreated with Sulfur, Sodium Metbisulfite, or Salt

Abstract

Pre-drying treatments have been found to improve the quality of stored sun-dried tomatoes. Based on previous investigation (Part I), 5 specific pretreatments were chosen for effects on nutritional value, sensory quality, and safety before and after 3 mo of storage (25 °C and 30% to 34% relative humidity). These pretreatments included (1) direct gas sulfuring with 2.3 kg (5 lb) SO 2 ; (2) with 3.6 kg (8 lb) SO 2 ; (3) dipping in 10% salt for 5 min; (4) 8% sodium metabisulfite for 5 min; and (5) 8% sodium metabisulfite and 10% salt for 5 min. The use of SO 2 improved color, rehydration ratio, and minimized the loss of ascorbic acid and lycopene. Sodium metabisulfite dipped tomatoes had better rehydration ratio and color than gas sulfured sun-dried tomatoes. Untrained consumers ranked gas sulfured tomatoes higher than sun-dried tomatoes produced by dipping in either sodium metabisulfite alone or sodium metabisulfite plus salt.

Antioxidant capacity and characteristics of theaflavin catechins and ginger freeze-dried extract as affected by extraction techniques

“…The observed variations in DPPH and ß-carotene were 42.01 to 51.36 and 40.02 to 48%, respectively [21] The higher antioxidant activity of tea flavonoids is attributed to the presence of a specific chemical structure dominated by vicinal dihydroxy and trihydroxy moieties that can quench metal ions and imparted electron delocalization thus ultimately proved helpful to reduce free radicals production. [22,23] The more extraction efficiency of ethanol for polyphenol as compared to other solvents are in harmony with the findings of Friedman et al,; Ghasemzadeh et al,; Ghasemzadeh et al, [24][25][26] they observed better tea polyphenol extraction through aqueous ethanol as compared to methanol and water. In this context, they elucidated solvent-to-material ratio, time and temperature can play a vital role.…”

Physicochemical and sensory properties of cow skin crackers from dry salt-preserved skin utilizing sodium meta-bisulfite (SMB)

“…This was the opinion of (43), who stated that increased brightness indicates inhibition of browning by sulfites. (44) added that using SMB can reduce color degradation and extend shelf life. Interestingly, in the preference test, there was an increase in the preference value with the addition of 6% SMB, followed by a decrease at a higher concentration.…”

Solar Tunnel Drying: Pretreatment on drying kinetic of plum tomatoes

“…The fresh tomato samples were sorted, graded, washed in water and then sliced into halves and quarters before pretreated. Tomato slices were immersed in 10% NaCl solution for 3 min according to latapi and Barrett (2006). Therefore, treatments were named as "non-pretreated-quarter, nonpretreated-half, pretreated-quarter and pretreatedhalf".…”

“…However, the natural convection solar dryers exhibit highly low buoyancy inside dryer (BAlA et al, 2003). Furthermore, conventional dryers are not economic because of high energy cost (gURlEk et al, 2009). At the other side, solar tunnel drier can be operated by a fan driven by photovoltaic module and this system removes moisture inside dryer.…”

“…Solar tunnel drier was utilized for drying of many agricultural products such as fruits, vegetables, cereals, grain, legumes, oil seeds, spices and even fish and meat (BAlA et al, 2003). Drying operation is performed to tomatoes for preservation purpose as well as alteration of taste, texture and flavor to satisfy consumer requirements and increase quality of the product for the market (BAlA et al, 2003;gURlEk et al, 2009).…”