Mango Processing, Products and Nutrition - Tropical and Subtropical Fruits: Postharvest Physiology, Processing and Packaging - page 269

Figure 15.1. Per capita fresh mango consumption in the United States (1980-2009) (source: Adapted from
USDA, 2011).

in fresh-cut products. The development of nonthermal and
other novel technologies alone or in combination can offer
consumers microbiologically safe fresh-cut tropical fruits,
with nutritional values and sensorial quality similar to those
of the intact product.
Postharvest stress-type treatments have been developed
to preserve fruits (Fig. 15.2), with many of these treat-
ments also being applicable to fresh-cut fruits. Some en-
zymatic and/or nonenzymatic antioxidant systems of the
fresh produce are activated by this stress, which contributes
to an adaptation process to stressful conditions and sub-
sequently the preservation of fruit quality and better an-
tioxidant potential (Lim et al., 2007). Gonzalez-Aguilar
et al. (2010) reported that to prevent injuries, plant cells
have developed mechanisms involving some secondary
metabolic compounds (flavonoids, lignans, carotenoids,
ascorbate, glutathione, etc.) and some enzymes (supeox-
ide dismutase, catalase, peroxidase, ascorbate peroxidase,
glutathione reductase, etc.) that convert reactive oxygen
species (ROS) into less-toxic products (ROS are involved
in signaling pathways for the production of antioxidant
molecules).
Some important attributes to be considered for the sen-
sory quality of a fresh-cut product are: (1) color or ap-
pearance, (2) texture, (3) flavor, (4) taste, and (5) overall
acceptance. However, from consumers' perspective, color
or appearance of fresh-cut produce is the single most impor-
tant factor among all the quality attributes mentioned above
(Siddiq et al., 2004). If the color of a fresh-cut product is
not acceptable or attractive, the consumer is least likely to

purchase it regardless of its excellent texture, flavor, taste,
or other quality attributes.
Two enzymes (polyphenol oxidase and peroxidase)
have been implicated in color deterioration in cut fruits
and vegetables. In addition to visible color changes, these
enzymes impair not only the other sensory properties and
hence the marketability of the product but often lower
its nutritive value as well (Vamos-Vigyazo, 1981). Both
enzymes have been widely studied in different fruits, with
special emphasis on minimizing their activities (Nicolas
et al., 1994; Weemaes et al., 1998; Siddiq and Cash,
2000; Guerrero-Beltran et al., 2005). Sulfites were used
extensively in the food industry to control enzymatic
browning. However, since the late 1980s, there has been
an effort to avoid the use of sulfiting agents in foods
due to safety, regulatory, and labeling issues (Lambrecht,
1995). A number of alternatives to sulfites, such as
ascorbic acid, citric acid, 4-hexylresorcinol, erythorbic
acid and sodium erythorbate (stereoisomers of ascorbates),
benzoic acid, honey, and natural fruit juices (e.g., lemon
juice), have been tried with varying success. Chitosan and
gum arabica coating (Huaqiang et al., 2004; Abdelgader
and Ismail, 2011), sodium hexametaphosphate (Pilizota
and Sapers, 2004), oxalic acid (Yoruk and Marshall,
2003), and NatureSeal, a commercially available product
containing calcium ascorbate (Arvind et al., 2004), are
the other alternatives tried more recently either alone
or in conjunction with other inhibitors. For peaches and
nectarines, which have flesh color similar to that of
mangoes, postcutting dips in ascorbate and calcium lactate