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The global meat industry is characterised by a growing interest in natural preservative additives. This study determined the effect of sweet basil (Ocimum basilicum L.) essential oil (SBEO) on colour and lipid oxidation in minced beef. The phytoconstituents of SBEO were analyzed by gas chromatography mass spectrometry. Thereafter, minced beef samples from Nguni and Boran cattle were treated with either no additives (control, C) or SBEO added at 2% (SB2), 4% (SB4), or 6% (SB6). The meat samples were aerobically packaged and stored (4 ± 1°C) for seven days for measurement of lightness (L⁎), redness (a⁎), yellowness (b⁎), hue, chroma, and lipid oxidation (acid-reactive substances, TBARS) on days 0, 4, and 7. Thirty-two bioactive compounds with reported antioxidant and antimicrobial and activities were identified in SBEO, including Estragole (41.40%), 1, 6-Octadien-3-ol, 3,7-dimethyl (29.49%), and trans-.alpha.-Bergamotene (5.32%). On days 0, 4, and 7, SB2, SB4, and SB6 had higher (P < 0.05) L⁎, a⁎, b⁎, hue, and chroma values; and on days 0 and 4 TBARS were lower (P < 0.05) in SB2 and SB4 than C and SB6. The addition of 2% and 4% SBEO improved colour and lipid oxidative stability, demonstrating potential for its use as a natural antioxidant additive in meat.

The effect of dietary inclusion of Moringa oleifera leaf meal (MOLM) on the feed conversion ratio (FCR) of finisher pigs, physico-chemical meat quality, fatty acid (FA) composition and shelf life of pork was investigated. A six-week feeding trial was conducted with 24 Large White x Landrace gilts aged 14 weeks. Each pig was housed individually and randomly allocated to one of four dietary treatments, containing 0%, 2.5%, 5% or 7.5% MOLM, with six replicates per treatment. Feed intake was measured daily, pig liveweight was measured weekly, and average daily gains (ADGs) and FCR were calculated. Pigs were slaughtered at 20 weeks old and measurements of backfat thickness, pH 45min and pH 24h were taken. Muscularis longissimus thoracis et lumborum muscle samples from each carcass were analysed for physico-chemical quality. Muscle, subcutaneous fat and feed samples were analysed for FA composition and health lipid indices of atherogenicity (AI) and thrombogenicity (IT) were calculated. A 10-day shelf-life study was conducted, during which instrumental and sensory meat colour and odour were assessed. Pigs fed 7.5% MOLM had significantly higher average daily feed intakes (3.56 kg/day) than pigs fed 0%, 2.5% and 5% MOLM (3.05, 3.14 and 3.07 kg/day, respectively). The FCR of pigs fed 0%, 2.5% and 5% MOLM did not differ significantly (3.34, 3.44 and 3.22, respectively). However, the FCR of pigs fed 7.5% MOLM was significantly poorer (3.78). No significant differences were observed for carcass and physico-chemical quality traits. MOLM inclusion improved shelf life, as meat samples from MOLM-fed pigs exhibited significantly prolonged acceptability of colour and odour during 10 days of refrigerated storage. Although the n-6 : n-3 FA ratios of the dietary treatments containing MOLM were significantly improved (T1 = 35.45, T2 = 22.08, T3 = 14.24, T4 = 15.90), no significant differences were observed for this ratio in the fat composition of the meat or subcutaneous fat samples between treatments. A significant reduction in intramuscular fat and stearic acid content was observed with increasing levels of MOLM. However, all other FA profiles, ratios and health lipid indices did not differ significantly across treatments. In conclusion, up to 5% MOLM may be included in finisher pig feed with no negative effect on feed conversion efficiency, carcass and meat quality traits, and may improve shelf life of pork. However, inclusion levels of 7.5% MOLM may lower FCR. The MOLM inclusion significantly improved the FA composition of the feed, but did not produce the desired improvements in FA composition of meat, probably because of the prominence of fat deposition by de novo lipogenesis in finisher pigs rather than direct incorporation of dietary fatty acids. ______________________________________________________________________________________

Droëwors are traditional South African salted and dried sausages, made without nitrites/nitrates and nonfermented. Different meat sources (beef, game and ostrich) are traditionally used in droëwors processing, while the use of pork is uncommon, as it is said to lead to rancidity. The first part of the study analysed the physico-chemical composition of commercially available beef, game and ostrich meat droëwors (n = 20). On average, they were composed of 26.3-29.2 g/100 g moisture, 41.3-44.0 g/ 100 g protein, 26.2-33.1 g/100 g fat and 5.9-6.5 g/100 g ash and 5.0-5.4 pH. Water activity (0.76-0.82) was sufficiently low to ensure shelf stability at ambient temperatures. In the second part beef and pork droëwors were formulated in accordance with these results and with similar fat content, dried for 2 days (30°C, 40% relative humidity) and stored for 26 days (25°C, 50% relative humidity); measuring moisture, water activity, pH and lipid oxidative stability (thiobarbituric acid reactive substances (TBARS)) weekly. At day 5, moisture and thus water activity of pork droëwors was slightly higher compared to beef ones and fat and ash content slightly lower (P B 0.05) despite similar weight loss. Even with slightly less fat, TBARS in pork droëwors were significantly higher after drying and throughout storage (3.83 vs 0.99 mg MDA equivalents/kg dry matter at a maximum).

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