Walnuts are important dried fruits, which are listed as the world four big dried
fruit with almonds, cashews, chestnut in the international market. Walnuts have good
nutritional value and medical care functions. In recent years, the green juglans are
more and more popular with people at home and abroad, have formed a certain
consumer market. The metabolism of postharvest green juglans were very strong and
easy fade. At present, there were few reports about green juglans preservation.
Therefore, the research of preservation technology of green juglans was badly in need
The experiment selected green juglans as experimental material. Through cold
storage, the proper storage temperature was chosen. In order to investigate the effect
of quality of green juglans, which could be treated with different concentrations
natamycin and 1-methylcyclopropene, different thickness PE packaging methods. The
aim was that the new fresh-keeping technology methods of green juglans could are
provided. In this paper, the main research results are as follows:
(1)In order to investigate the effect of different storage temperatures on the
freshness retaining of green juglans, the green juglans were stored under (5±1℃),
(0±0.5℃), (-1±0.5℃). The result showed that: the group of (-1±0.5℃) storage
temperature could delay the decrease of moisture content, increase of a*and increase
of acid value. (-1±0.5℃) could reduce the decrease of fruit firmness. The activities of
peroxidase (POD) were promoted effectively and the activity of polyphenol oxida
(PPO) was reduced effectively, in turn, the ripening of green juglans was delayed.
Compared with the control group(45d), the storage period of the experimental groups
were extended 30d and 45d.The result of green juglans under different storage
temperatures was in the following order:(-1±0.5℃), (0±0.5℃), (5±1℃). Therefore,
the optimum storage temperature of green juglans was (-1 ± 0.5℃).
(2) In order to investigate the effect of different concentrations natamycin on the
freshness retaining of green juglans, the green juglans could be treated with different
concentrations (600mg∕L、800mg∕L、1000mg∕L) natamycin and stored them at (0±0.5)℃.
The result showed that: compared with control group of cold storage, natamycin
treatments could regulate the physiological metabolism and antiseptic effect.
Natamycin treatments could be effective to inhibit fruit deterioration. The storage
quality of green juglans was evidently improved by natamycin treatments. The study
showed that 1000mg/L natamycin treatment could reduce effectively the decrease of
decay rate. Original color of green juglans was kept by natamycin treatments.
1000mg∕L natamycin treatment can delayed the decrease of MDA content. The
activity of catalase (CAT) was promoted effectively, the