Multilayer coatings have received recent interest to overcome the problem of the poor adhesion
between the commonly hydrophobic coatings and the hydrophilic surface of fruits. In the layer-by-layer
technique fruits and vegetables are dipped into different solutions with opposite charged polyelectrolytes
with the aim to obtain strong chemical bonds between them [71]. In this context, pectins have been
studied in combination with other edible matrices, such as alginate or chitosan. Multilayer coatings were
successfully prepared with the layer-by-layer technique by using a solution of sodium alginate containing
one antimicrobial agent (trans-cinnamaldehyde encapsulated in β-cyclodextrins (β-CD-trans)) in
combination with pectins and calcium lactate solutions to obtain stable and homogeneous coatings [70].
Authors reported that multilayer coatings with 1% alginate, 2% β-CD-trans and 2% pectins maintained
the quality and organoleptic attributes of fresh-cut watermelon while extending the shelf life at 4 °C
from 7 (control) to 12 days. In addition, microbiological analysis demonstrated the effectiveness of the
encapsulated agents in the multilayer coatings against microbial growth. The application of multilayer
coatings formed by chitosan (2%), 2% β-CD-trans and pectins (1%) (optimum formulation) was reported
with the extension of shelf-life of fresh-cut cantaloupe at 4 °C up to 9 days [71]. Similar multilayer
coatings were also successful in prolonging the shelf-life of fresh-cut papaya [72]. In both cases, calcium
chloride (2%) was used as cross-linking agent.