2.1. Materials: -
2.1.1. Fish sample:- Sardine fish (Sardinella aurita) used in the current study
(average weight 115g ± 10g) was obtained from (January, 2017) from Max Bay, Alexandria, Egypt. Fish was placed (in ice tanks) in crushed ice with a fish/ice ratio of 1:3 (w/w) and transported (within 1 hr. from the caught) to the Department of Food Sciences, Faculty of Agriculture, Saba Bacha, Alexandria University for further treatments..
2.1.2. Potato and other ingredients:- The fresh Potato tubers (Solanun tuberosum), Rosemary (Rosmarinus officinalis) and other ingredients were purchased from local markets at Alexandria, Alexandria Governorate, Egypt.
2.1.3. Chemicals:- All the chemicals …show more content…
2.2.1. Fish samples preparation:- Fresh Sardine fish (Sardinella aurita) were immediately washed, eviscerated as described by (Taheri et al., 2012) with stainless steel knife and washed again ( fresh cold distilled water (4 °C) .The fish were cleaned , filleted by hand.and drained for 20 min on a sanitized stainless steel throughout refrigerated storage and then treatments .
Preparation of the plant extract: - 2. 2.2.
2.2. 2.1 Preparation of potato peel extract:-
Extracts were prepared from potato peels using the procedure described by Singh and Rajini (2004 ) by some modifications as follows: Potato tubers (Solanun tuberosum), were washed with tap water and peeled manually using a kitchen vegetable peeler, the peels (this by-product, which represents one of the main resulting from the potato processing) were dried in a hot air oven at 45 C for 72 h and powdered by a kitchen blender. The material that passed through an 80 mesh sieve was retained for use. For the preparation of water extract, 10 g of powdered peel were extracted overnight with 100 ml of distilled water and shaking at room temperature and centrifuged at
2800 rpm for 10 min. The supernatant was collected in a …show more content…
Another group, frozen fillets were
glazed by dipping (the ratio of fish to dipping solution was 1⁄10 (w ⁄ v) in container continuously supplied with fresh cold aqueous solutions of potato peel extract (4 °C) for 30 seconds (PPE ,2nd group). While, the third group, frozen fillets were
glazed by dipping (the ratio of fish to dipping solution was 1⁄10 (w ⁄ v) in container continuously supplied with fresh cold aqueous solutions of rosemary extract (4 °C) for 30 seconds (RE , 3rd group). The last group, frozen fillets were
glazed by dipping (the ratio of fish to dipping solution was 1⁄10 (w ⁄ v) in container continuously supplied with fresh cold aqueous solutions mixture of potato peel and rosemary extract (4 °C) for 30 seconds (PPE+RE , 4rd group).
glaze treatment, samples were packed into polyethylene bags and immediately stored under freezing conditions (–18 °C) for six months, FAO, 2009 and Vanhaecke et) al., 2010).
During this time, samples were taken randomly each month to analysis the same way. Prior to analysis, the samples of fish from these groups were thawed in cold conditions (4