Application of Pomegranate Peel Extract (PPE) withSodium Alginate (Alg-Na) Coating on Fruit Decay Controland Quality Postharvest of Sweet Lemon Fruit cv Mahali

Replacement of synthetic pesticides and antifungal compounds with naturalones for reducing the decay of agricultural products is a challenge in the industry.

In order to investigate the effects of sodium alginate (Alg-Na) andpomegranate peel extract (PPE) on reduction of decay and improving the postharvest qualityof sweet lemon fruit, an experiment based on Completely Randomized Design (CRD) with sixtreatments and three replications was conducted. Treatments included Control (C), SodiumAlginate (Alg-Na 1%), PPE, PPE/Water ratio of 1:1, PPE/Water ratio of 1:2, PPE/Water ratioof 2:1 combined with Alg-Na 1%. Treated fruits were kept for 35 days at 20 oC and the fruitcharacteristics were evaluated at seven day intervals. Traits such as weight loss%, fruitfirmness (N), total acidity (TA %), pH, TSS%, vitamin C, fruit skin color (a*, b* and L*) andorganoleptic properties were measured.

The results showed that postharvest application of PPE and Alg-Na 1% hadsignificant effect on maintenance of sweet lemon in storage as compared to untreated fruits.The lowest fruit decay and microbial concentration was obtained in fruit treated with PPE andAlg-Na 1% as compared to other treatments. The lowest weight loss% was obtained in fruittreated with PPE and Alg-Na 1% and the highest was observed in untreated fruits. Fruittreated with PPE and Alg-Na 1% showed the highest fruit firmness at the end of storageperiod as compared to the control. The highest vitamin C at the end of storage was observedin fruit treated with PPE and Alg-Na 1%. The sensory test showed that consumer'sacceptability was increased by increasing the PPE concentration plus at Alg-Na 1%.

Our study suggests that the use of PPE combined alginate coating has thepotential to maintain sweet lemon quality and extend its postharvest life to 35 days.