UV-C treatments extend the shelf life of fresh-cut peppers by delaying pectin solubilisation and inducing local accumulation of phenolics

RODONI L; ZARO MJ; HASPERUÉ HJ; CONCELLON, A; VICENTE, AR

LEBENSMITTEL-WISSENSCHAFT UND-TECHNOLOGIE-FOOD SCIENCE AND TECHNOLOGY

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2015

0023-6438

Red pepper (Capsicum annuum L.) sticks were treated with different doses (3, 6, 10 or 20 kJ m-2) of UV-C radiation applied in different zones (inner: I, outer: O and both inner and outer: I/O). Pepper sticks treated with 20 kJ m-2 I/O showed the lowest decay at 10 ºC and this treatment was selected to further determinations. Fungal decay, soft rot, electrolyte leakage, weight loss and respiratory rate were lower in treated than control pepper sticks during storage at 5 ºC. At 12 d control sticks lost 50 % of initial firmness, while in UV-C treated sticks remain unchanged. Similar effects were found in resistance to deformation. No changes in sugars, color and acidity from UV-C treatment were found. The total antioxidants rise during storage, without differences between treatments. At 12 d higher phenols compounds were found in UV-C treated sticks. Histochemical analyses showed a higher phenols accumulation in UV-C treated than control sticks during storage in both cuticle and pulp tissue. At 7 d, pectin solubilization was 3-fold higher in control than treated sticks. Despite the notable reduction in decay, no relevant microbial reduction was found derived from UV-C treatment. Results suggest that phenols accumulation and lower pectin solubilization under UV-C treatment help to maintain tissue integrity hindering pathogen proliferation in fresh-cut pepper.