Effect of Edible Coatings Containing Soy Protein Isolate (SPI) on the Browning and Moisture Content of Cut Fruit and Vegetables

Abstract

Effectiveness of edible coatings containing soy protein isolate (SPI), in reducing oxidative browning and moisture loss during storage (4 o C) of cut apples, potatoes, carrots, and onions was investigated. The SPI coatings were shown to have antioxidative activity. Furthermore, addition of carboxymethyl cellulose (CMC) to the formulations significantly improved its antioxidative activity. Oxidative discoloration, as determined by Commission Internationale De I'Eclairage (CIE) lightness (L*), redness (a*), and yellowness (b*) color scale, was significantly reduced (p <0.05) by SPI coating treatments over a storage time of 120 min. Loss of lightness was reduced by SPI coatings with and without CMC. These respectively showed 4.03 and 3.71% change of L* value compared to 8.56% for control. Browning of the control in cut potatoes was significantly increased by 106.6% in contrast to 34.3 and 35.2% for SPI coatings with and without CMC, respectively. The b* values also reflected effectiveness of SPI. Moisture barrier effect was significantly better for the treatments, compared to the control. SPI coatings reduced moisture loss in apples and potatoes, respectively, by 21.3 and 29.6% over the control. Cut onions did not show any treatment effect both in terms of browning and moisture loss. SPI coatings prove to be good moisture barrier and antioxidative property.

Effect of ferulic acid on the performance of soy protein isolate-based edible coatings applied to fresh-cut apples

“…Within the controls, similar results were obtained for the apples dipped into both antioxidants solution. Within the coatings and contrary to what was observed by Shon and Choi (2011), the SPI coating was not effective in reducing the weight loss of apples from the first day. This result might be attributed to some aggregation of the SPI by contact with the surface of the apple which has a pH near the isoelectric point of the protein.…”

“…Ghidelli, Mateos, Rojas-Argudo, and P erez-Gago (2015) also reported positive effects of a SPI-based coating formulation (incorporating beeswax) applied in combination with modified atmospheres to fresh-cut artichoke. In another study (Shon & Choi, 2011), the effectiveness of edible coatings containing SPI was demonstrated in reducing moisture loss of apples and potatoes in a five days period, particularly in combination with CMC, though final moisture loss for the best formulation was still over 20%. However, though the authors claim positive effects on oxidative discolouration, the colour study was terminated after 120 min due to excessive browning, which is clearly ineffective.…”

Effect of Antimicrobial and Antioxidant Rich Pomegranate Peel Based Edible Coatings on Quality and Functional Properties of Chicken Nuggets

“…In another study, whey protein and soy protein coatings were applied on sausages and beef, respectively, during refrigerated storage to evaluate the products' safety and quality. The results of this study [32], are similar to the current findings. Topuz et al [33] reported that pomegranate juice has a high amount of phenolic compounds.…”

Gelatin and Gelatin/Rice Starch Coatings Affect Differently Fresh-Cut Potatoes and Colocasia Slices

“…Similar results were found in some studies where the effect of two different coatings based on soy protein and chitosan on fresh potato samples was studied, respectively. The soy protein-based coating protected the samples from enzymatic browning [63,64].…”