No abstract

The effects of methylcellulose (MC) coating enriched with Pimpinella affinis essential oil (PAO) on quality and shelf life of fresh silver carp fillets during refrigerated storage (4 ± 1C) were examined over a period of 16 days. MC solution (3%) and MC enriched with PAO (1.5% v/v concentration) were prepared for coating of the fish samples. The control and the treated fish samples were analyzed periodically for microbiological (total viable count), chemical (pH, thiobarbituric acid [TBA], total volatile basic nitrogen [TVB-N], free fatty acid [FFA] and pv) and sensory characteristics. According to results (pv, FFA, TBA, TVB-N, pH), color and odor on MC contain 1.5% PAO and have less change in comparison to other treatments (P < 0.05), and it could inhibit a total bacteria growth and psychrophilic counts of fillet. The results indicated that MC contains 1.5% PAO, a good antioxidant activity, so it can be used for fish preservation without any undesirable changes in antimicrobial and sensorial attributes. PRACTICAL APPLICATIONSThe main practical application behind the development of chitosan coating is used to preserve fish quality with the fact that these polysaccharides represent a renewable source of natural biodegradable polymers and meet with the emergence of more and more food safety problems. The results of this study are a useful tool for the development of new environment-friendly and healthier commercial applications in the food processing industry because of its antimicrobial and antioxidative characteristics.

In this study, the thermal stability of some phenolic antioxidants including flavonoids (quercetin and catechin) and phenolic acids (gallic acid, tannic acid, ellagic acid and caffeic acid) in tallow olein was investigated. Tallow olein fractionated from sheep tallow fat was used as a medium to study the antioxidant activity at 120, 140, 160 and 180°C. In order to extract tallow olein, a three‐stage fractionation method was performed on sheep tallow fat at the constant temperatures of 25, 15 and 5°C using acetone as a solvent. The results suggested that quercetin and ellagic acid had the highest thermal stability amongst others, while gallic acid and caffeic acid exhibited the least thermal stability.Practical applications: The sheep tallow fat has been primarily used in soap manufacturing and its application as an edible fat has been limited due to its high content of saturated fatty acids. Extraction of the liquid phase of tallow fat (tallow olein) by fractionation reduces its long‐chain saturated fatty acid content to an acceptable level for edible consumption. The fractionation process, as negatively affects the stability to autoxidation, should be followed by stabilisation with antioxidants. The recent interest in natural antioxidants encouraged the authors to investigate the thermal stability of phenolic antioxidants in tallow olein. It is necessary to determine the thermal stability of antioxidants to predict their appropriateness to be used in high‐temperature applications such as deep frying. Fractionation and stabilisation with appropriate antioxidants are the important steps to utilise tallow olein as an edible oil for different applications in salad formulations, cooking and frying.

Physiochemical and sensory evaluation of the reduced-sugar biscuits containing 0, 50 and 100% stevioside (Stevia rebaudiana Bertoni) as sugar replacement were investigated. Results showed that the stevioside substitution in biscuit formulation had no significant effects (P<0.05) on ash, fat and protein contents of biscuit but the pH and moisture content significantly increased. Complete replacement of sucrose with stevioside reduced calorie levels up to 15% in biscuit formulation. Specific volume, volume and bulk density had no considerable change with increasing stevioside level but diameter and expansion coefficient significantly decreased. The stevioside replacement increased the thickness and water activity. Addition of stevioside in the various biscuit formulations reduced the texture hardness, while their flexibility significantly increased. Stevioside incorporation resulted in the production of lighter biscuits with higher L* and a* and lower b* colour values. Sensory evaluation of biscuits prepared with equal ratio of sugar to stevioside (50:50) exhibited the highest sensory scores for flavour, colour, taste and overall acceptability.

No abstract