Isolation of Tomato Seed Meal Proteins with Salt Solutions

Abstract

Salt solutions were used in isolating tomato seed meal proteins. Na 2 SO 3 and NaCl solutions at different concentrations, and pH were included in a central composite design to find optimum conditions of protein isolation. The highest total protein yield was achieved with water extraction (no salt present). Salt extraction at pH 7.5 produced isolates with protein content of 93.4% (NaCl 5% w/v) and 77.1% (Na 2 SO 3 0.5% w/v). Observed values were in good agreement with predicted values. Isolates extracted with different salt solutions ranged from less soluble but very resistant to heat and Ca 2ϩ , to very surface active with functional properties comparable to commercial soy isolates.

Extractability of African yam bean (Sphenostylis stenocarpa) protein in acid, salt and alkaline aqueous media

“…This increase in the extractable protein when compared with that of saltfree water (distilled water) was more than 100%. Lower or higher concentration range of NaCl solution than that observed here had been reported for optimal extraction of vegetable protein; 0.3 M was found to be optimal for winged bean and faba bean (McCurdy & Knipfel, 1990;Okezie & Bello, 1988); 0.8 M for tomato seed (Liadakis & Tzia, 1998), 1 M for coconut and sunflower (Chakraborty, 1985;Venktesh & Prakash, 1993) and up to 2.0 M gave the optimal (82%) extractable sesame protein (Prakash, 1986) . In all the salt concentration range (0.0001-2.0 M), only few of the salt solution concentrations did not give better extractable protein than that obtained in ordinary distilled water.…”

Functionality of oilseed protein products: A review

“…Sodium chloride has been proposed at different concentrations for the extraction of protein from cottonseeds (Mieth & Kroll, 1984), grapeseed (Abd El-Aal, 1992), tomato seeds (Liadakis, Tzia, Oreopoulou, & Thomopoulos, 1998), Crambe abyssinica (Massoura, Vereijken, Kolster, & Derksen, 1998a, 1998b, canola (Barker, Martens, & Murray, 2002;Barker, Green, & Lei, 2003;Newkirk, Maenz, & Classen, 2003), hazelnut (Moure, Rú a, Sineiro, & Domínguez, 2002b) and Rosa rubiginosa seeds (Moure, Sineiro, & Domínguez, 2001), among others. Sodium sulfite was used during the extraction of proteins from sunflower to prevent oxidation of polyphenols (Roloff et al, 1989;Yazicioglu, Goekcen, & Karaali, 1981) and from tomato seeds (Liadakis et al, 1998); sodium bicarbonate and carbonate for the extraction of protein from soy, sunflower and lupin (Taha, Abbasy, El-Mockrashy, & Shoeb, 1981;Taha, Mohamed, & El-Mockrashy, 1986a, 1986b and sodium phosphate during the extraction of soy proteins . Calcium oxide (Newkirk et al, 2003) and hydroxide allowed the production of light coloured oilseed isolates (Taha et al, 1986a(Taha et al, , 1986b and low phytic acid content of canola isolates (Tzeng et al, 1990).…”

Response surface methodology for protein extraction optimization of red pepper seed (Capsicum frutescens)

“…The process variables and the responses were defined from published data (Liadakis et al, 1995;Liadakis, Tzia, Oreopoulou, & Thomopoulos, 1998;Mizubuti, Junior, Souza, Silva, & Ida, 2000;Moure et al, 2002;Oomah, Mazza, & Cui, 1994;Quanhang & Caili, 2005;Rustom et al, 1991). The effect of the variables temperature (x 1 ), pH (x 2 ), time of extraction (x 3 ) and solvent to meal ratio (x 4 ) in the pepper seed protein isolation process was investigated.…”