Browning, enzymatic inhibition

In this industry ED processing might be applied in three main areas, that is, de-acidification, desalting, and enzymatic-browning inhibition. 

Tronc J-S, Lamarche F, and Makhlouf J. Enzymatic browning inhibition in cloudy apple juice by electrodialysis. J. Food Sci. 1997 62 75-78. 

Lozano-De-Gonzalez, P.G. et al. Enzymatic browning inhibited in fresh and dried apple rings by pinapple... 

Sucrose helps minimize earthy tastes of vegetables, while enhancing inherent flavors and aromas, and preserving color and texture (37). Addition of sucrose inhibits enzymatic browning of canned and frozen fmits, and prevents loss of color, flavor, and aroma from fmit during processing (38). 

Luo Y and Barbosa-Canovas GV. 1997. Enzymatic browning and its inhibition in new apple cultivar slices using 4-hexylresorcinol in combination with ascorbic acid. Food Sci Technol Int 3 195-201. 

Ozoglu H and Bayindirli A. 2004. Inhibition of enzymatic browning in cloudy apple juice with selected antibrowning agents. Food Control 13 213-221. 

Humic substances. Analogous to the reactions described above, humic substances (the polymeric pigments from soil (humus) and marine sediments) can be formed by both enzymatic and non-enzymatic browning. High concentrations of free calcium and phosphate ions and supersaturation with respect to hydroxyapatite can sustain in soil, because adsorption of humic acids to mineral surfaces inhibits crystal growth (Inskeep and Silvertooth, 1988). A similar adsorption to tooth mineral in a caries lesion can be anticipated for polycarboxylic polymers from either the Maillard reaction or enzymatic browning. 

FIG. 18 Schematic layout of a two-compartment configuration using bipolar (bmp) and anionic (a) membranes proposed to inhibit enzymatic browning of cloudy apple juice (Tronc et al., 1998) via preliminary acidification to pH 2.0 and subsequent de-acidification to pH 3.5 by reverting flow of HCl and apple juice streams. 

Inhibition of Enzymatic Browning in Cloudy Apple Juice.603... 

Electrodialysis with bipolar membranes (EDBMs) [23] was applied recently to the production of mineral and organic acids [24-36], inhibition of enzymatic browning [37-39], and separation of protein [40-44]. These applications are based on water dissociation at the interface of a bipolar membrane (BPM) coupled with monopolar membrane action. A recent up-to-date overview gives the possibilities and the economic relevance of BPM technology [45]. 

FIGURE 21.20 Electrodialysis cells for inhibiting enzymatic browning in cloudy apple juice, (a) Electroacidification step and (b) electro-alkalinization step. CEM, cation-exchange membrane BPM, bipolar membrane AEM, anion-exchange membrane. 

Ding, C. K., Chachin, K., Ueda, Y., and Wang, C. Y. (2002). Inhibition of loquat enzymatic browning by sulfhydryl compounds. Food Chem. 76, 213-218. 

Tyrosinase inhibition may be a potential approach to prevent and control the enzymatic browning reactions and improve the quality and nutritional value of food products [20]. Tyrosinase also plays a major key role in the developmental and defensive functions of insects. Tyrosinase is involved in melanogenesis, wound healing, parasite encapsulation, and sclerotization in insects [21-23]. For these reasons, in recent years the development of tyrosinase inhibitors has become an active alternative approach to control insect pests [20]. Additionally, it is now well-recognized that tyrosinase inhibitors are important for their potential applications in medical and cosmetic products [24-26]. 

Mammalian skeleton muscle at rest contains 350-400 mg ATP per 100 g. ATP inhibits enzymatic browning of raw edible plant materials, such as sliced apples, potatoes, etc. 

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