Effects of prefrying times on the nutritive value of canned tilapia meat

Abstract

Tilapia meat was placed in the fryer filled with frying oil preheated to 180 OC. The frying times were 2, 5,10, 15, or 20 min. The fried meat was then packed in 209 X 409 cans, hermetically sealed, and retorted. As the frying time increased beyond 10 min, available lysine and in vitro protein digestibility of the meat decreased significantly (P < 0.05) in fried tilapia meat. Rats on diets of tilapia meat fried for 15 or 20 min containing 10% protein had poor growth and lower net protein utilization (NPU) (P < 0.05) than that of rats on diets of tilapia meat fried for 2 or 5 min. Canned tilapia meat prefried for 15 min had higher sensory scores of odor and flavor, whereas the scores of color and texture were high for canned tilapia meat prefried for 10 min.The value of fish for human nutrition lies in the relatively high protein content, good digestibility, and high biological value of fish proteins (Geiger and Borgstrom, 1962).Tilapia are mainly lacustrine fish that are well adapted to enclosed waters. They exhibit many qualities that suit them for culture, including resistance to handling and disease, efficient conversion of low-protein diets, ease of breeding, and high palatability; thus, they are an important human protein source in many tropical and subtropic countries. In Taiwan, tilapia production has surpassed the production of milkfish, and thus tilapia has become the preeminent cultured fish species, with yearly production exceeding 100 000 tons.Various processing procedures must be applied to foods for preservation, quality improvement, and consumer convenience and/or to increase their market value.The purpose of the study was to evaluate the effects of different prefrying times on the nutritional value of canned tilapia meat. MATERIALS AND METHODS Product Preparation.Live commercially harvested tilapia were obtained from the local market. Fish weighed between 700 and 900 g each. After the fish were butchered and rinsed with water, the scales, head, tail, viscera, and central bone were discarded. The remaining tilapia meat was cut into pieces 9 X 2.5 X 1.5 cm and fried in soybean oil (President Food Co.), at a meat to oil ratio of 1:4 (weight) at 180 OC. Frying times were 2,5,10,15, or 20 min. Fresh frying oil was used for each variable frying period. The fried tilapia were cooled and packed in 209 X 409 cans. A total of 150 cans were packed for each treatment, and in each can solid meat were placed with sufficient patching to give a net weight of 90 g. Thirtymilliliter portions of seasoning were then placed on top of the meat, leaving a headspace of about 10 mm. The composition of seasoning per liter of water was sugar, 125 g; salt, 25 g; monosodium glutamate, 25 g; soy sauce, 57 mL; rice wine, 12 mL; and vinegar, 8 mL. All cans were sealed immediately after being exhausted for 15 min. The cans were then stem-retorted at 118 "C for 40 min, allowed to cool under running water, stored at room temperature, and opened 4 weeks after processing. The contents of all 150 cans of each variable were drained thro...

The effect of different cooking methods on proximate composition and lipid quality of rainbow trout (Oncorhynchus mykiss)

“…, 1994; Garcia‐Arias et al. , 2003), and the frying duration (Shiau & Shue, 1989; Hoffman et al. , 1994).…”

“…Many researchers found higher lipid contents in fried fish fillet than those in raw or other cooked fish fillets as a consequence of the absorption of the oil by the fillets (Mustafa & Medeiros, 1985;Steiner-Asiedu et al, 1991;Gokoglu et al, 2004). In addition, it was reported that the amount of lipid in the fried fish, which was expressed on a dry-weight basis, could change depending on the initial lipid content of the fish (Mai et al, 1978;Gall et al, 1983;Hoffman et al, 1994;Garcia-Arias et al, 2003), and the frying duration (Shiau & Shue, 1989;Hoffman et al, 1994). In the present study, the lipid contents of the fried fish samples were found to be higher than the fresh ones.…”

Quality of Ready to Serve Tilapia Fish Curry with PUFA in Retortable Pouches

“…In many tropical and subtropical countries, fresh tilapia is becoming a popular substitute for quality animal protein source for human consumption, due to its fast growing, resistant to disease and handling, reproduction in captivity, efficient conversion of low‐protein diets, and for being able to tolerate a wide range of environmental conditions (Shiau and Shue 1989). The global production has been greatly influenced by a rapid expansion of Nile tilapia ( Oreochromis niloticus ) and Mossambique tilapia ( Oreochromis mossabicus ) culture in many reservoirs.…”

“…The available literature in India on thermal processing of tilapia is very meager. Shiau and Shue (1989) studied the effects of prefrying times on the nutritive value of canned tilapia meat. However, market for processed foods has been growing at a greater rate due to changes in life style and food habits of the people.…”

Elaboration process, chemical and sensory analyses of fried-salted soybean

“…That could be an explanation for the significant decrease in proteins and the relative increase in carbohydrates. Other authors found total nitrogen and protein decrease in other fried foods (Ponnampalam and Mondy, 1983;Shiau and Shue, 1989). Significant differences between RS and SFF3 were not detected in ash content.…”