Use of L-ascorbic acid diesters to preserve rabbit meatballs

Consumers appreciate rabbit meat because of its lean meat rich in polyunsaturated fatty acids (PUFA). However, PUFA are highly prone to be oxidised, thus they need to be preserved during handling and storage. Among the others, antioxidant addition to meat products is considered an effective strategy; however, consumers’ demand for natural products is rising. L-ascorbic acid (Vit. C) is one of the most potent water-soluble antioxidants whose functionalisation of the hydroxyl groups at the C-5 and/or C-6 may represent a solution to obtain effective L-ascorbic acid derivatives with improved lipophilicity. On this basis, we aimed to evaluate whether L-ascorbyl-5,6-O-dialkanoates prepared from miristic (MA) and stearic (SA) acids could be employed as novel semisynthetic antioxidants to protect rabbit meatballs from oxidation. The carcass meat (without hind legs, and Longissimus thoracis et lumborum muscles) were obtained from nine male rabbits (New Zealand White × California) for a total of 1400 g. After mincing, meat was divided into three groups: no additive (control, C), L-ascorbyl-5,6-O-dialkanoates from myristic acid (MA group), and L-ascorbyl-5,6-O-dialkanoates from stearic acid (SA group). Antioxidant powder was ad hoc synthesized and added at 0.1% (w/w). Overall, 48 meatballs were prepared and 4 meatballs for each group were analyzed immediately (T0) and after 20 (T20), 40 (T40), and 80 (T80) days of frozen storage (−10 °C). Weight loss (WL, %), primary (conjugated dienes CD, mmol hydroperoxides/ 100g meat) and secondary (thiobarbituric acid reactive substances, TBARS; mg MDA-eq./kg meat) lipid oxidation products were quantified. Fatty acid (FA) profile was determined by gas chromatography. The PROC GLM of SAS was used to analyse the data with antioxidant and storage as fixed effects. Antioxidants showed a marginal protection against meat oxidative damages. The WL of SA was higher (p = .076) than C and MA, being 2.59, 2.15, and 2.49%, respectively. No effect on CD emerged, while TBARS was lower (p = .061) in MA and C group than SA (0.512, 0.556, 0.815 mg MDA-eq./kg meat). Between T0 and T20, CD increased from 0.030 to 0.079 mmol Hp/100g meat and saturated FA from 35.37% to 36.21% of total FAME, contrariwise PUFAn-6 passed from 35.54% to 33.03% total FAME. Between the two tested antioxidants, only L-ascorbyl-5,6-O-dialkanoate from myristic acid seemed to slightly preserve meat quality during storage. Further trials are necessary to identify if higher concentrations would show more specific protection.