PHYSICOCHEMICAL, MICROBIOLOGICAL AND SENSORY CHARACTERISTICS OF PERSIMMON FRUIT LEATHER

Document Type : Original Article

Authors

1 Food Technol. Res. Inst., Agric. Res. Cent., Giza, Egypt

2 Food Sci. Dept., Fac. Agric., Zagazig Univ., Egypt

Abstract

Persimmon fruit leather is a dehydrated persimmon product, which was consumed as
a chewy for preparation of valuable nutritive dessert. The aim of the present study was to utilize
persimmon puree in the preparation of persimmon leather and study physicochemical, microbiological
and sensory characteristics of persimmon leather. Persimmon fruit leather was prepared by drying a
mixture of persimmon puree treated with hot break by steam (HST), mango puree, glucose syrup,
sugar, pectin, citric acid and starch. Dehydration was performed in microwave at 55ºC for 30 min.
Leather was also prepared from persimmon leather using the same ingredients except starch. Results
showed that texture properties of leather containing starch was higher than leather without starch.
Moisture, ash content and acidity were close to each other in persimmon leathers with or without
starch. TSS content in persimmon leather product samples were 78.89º Brix and 79.14º Brix, while
total and reducing sugars of leather without starch recorded 83.26 and 45.08%, respectively.
Persimmon leather with starch contained total and reducing sugars 81.48 and 44.90%, respectively.
Ascorbic acid retained in persimmon leather containing starch was slightly higher (14.26 mg/100g)
compared to leather without starch (13.52 mg/100g). Browning index increased when adding starch to
the formula. Alcohol insoluble solids (AIS) and crude fibers content were 12.87 and 0.98% in
persimmon leather with starch, respectively, whereas the respective values in persimmon leather
without starch were 8.73 and 0.82%. Antioxidant activity and carotenoids contents were higher in
persimmon leather containing starch than that without starch. Polyphenols, flavonoids and tannins
contents were lower in persimmon leather containing starch than leather without starch. Pyrogallol and
E-vanillic were the dominant compounds in both of persimmon leathers with and without starch.
Vitamin K represented the highest content among all studied vitamins in persimmon leather. Lightness
value (L*) was 33.81 in persimmon leather containing starch which is higher than lightness value (L*)
in persimmon leather without starch (23.72). The values of (a*) and (b*) were higher in persimmon
leather without starch (12.71 and 12.97, respectively) than in persimmon leather containing starch
(8.10 and 8.16, respectively). Total bacteria count was 110 CFU/g in just first dilution in persimmon
leather with starch but it was not detected in other dilutions, total count bacteria was not detected in
persimmon leather without starch in all dilutions. Molds and yeasts and spore forming bacteria counts
were not detected in all persimmon leather samples.

Keywords