Moringa oleifera leaf powder as a functional antioxidant additive in pork droewors
- Authors: Mukumbo, Felicitas Esnart
- Date: 2016
- Subjects: Antioxidants , Moringa oleifera , Pork -- Quality
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10353/15354 , vital:40400
- Description: The study investigated the effect of Moringa oleifera leaf powder (MLP) on physico-chemical characteristics, antioxidant activity, antioxidant compound content and lipid oxidation in pork droëwors. Firstly, the physico-chemical properties (proximate composition, salt content, water activity (aw), pH) of commercially produced droëwors from different types of meat (beef, game, ostrich) were determined. In the second experiment beef and pork droëwors with similar fat content were produced. Physico-chemical properties and lipid oxidation (thiobarbituric reactive substances (TBARS)) during processing and 26 days of storage at 25 °C and 50percent relative humidity (RH) were measured. In the third experiment, antioxidant compounds (Total Phenolic Compounds (TPC), α-tocopherol, β-carotene) in MLP were quantified. Thereafter, 4 treatments of pork droëwors were produced, with MLP included at 0, 0.5, 1 and 2 g/ 100 g. Physico-chemical properties and TBARS were measured at intervals during drying (0, 1.5, 5.75, 27.25, 72 h) and after 7 days of storage under ambient conditions. Antioxidant activity (ferric reducing antioxidant power (FRAP)), TBARS, α- and γ-tocopherol, and β-carotene contents were measured. In the fourth experiment, three batches of droëwors were produced (C: no antioxidant, M0.75: 0.75 g/ 100 g MLP, VE: 15 mg/ kg α-tocopherol oil) and stored at 25 °C and 50percent relative humidity for 112 days. Drying kinetics and α-tocopherol contents of pork droëwors after drying were measured and the physico-chemical properties and TBARS were followed during storage. Results showed no differences (P > 0.05) in the physico-chemical characteristics of beef, game meat and ostrich droëwors; containing on average 25.8 ± 1.25 g/100 g moisture, 42.0 ± 0.10 g/100 g protein, 32.0 ± 1.68 g/100 g fat, 6.2 ± 0.13 g/100 g ash and 4.2 ± 0.10 g/100 g salt; with aw and pH of 0.79 ± 0.015 and 5.3 ± 0.05, respectively. During processing and storage, TBARS were higher (P < 0.05) in pork droëwors (maximum 3.83 mg MDA/kg DM) than in beef (maximum 0.99 mg MDA/kg DM). Moringa oleifera leaf powder contained high levels of TPC (7.5 ± 0.2 mg gallic acid eq/g) and substantial levels of α-tocopherol (76.7 ± 1.9 mg/100 g) and β-carotene (23.2 ± 2.8 mg/100 g). The FRAP, α-tocopherol and β-carotene content of pork droëwors increased (P < 0.05) proportionally with increasing levels of MLP inclusion. Lipid oxidation occurred more rapidly (P < 0.05) when MLP was not added and was similar (P > 0.05) for all MLP treatments. There was no significant effect of the inclusion of 0.75 g/100 g MLP on the drying curves and physico-chemical characteristics of the droëwors. The α-tocopherol content was higher (P < 0.05) and TBARS during storage were lower (P > 0.05) with MLP addition. The results of the current study give an overview of the composition of commercial droëwors and showed higher susceptibility to lipid oxidation in pork droëwors. Moringa oleifera leaf powder exhibited antioxidant activity in pork droëwors, inhibited lipid oxidation and increased the content of α-tocopherol in the product. It can be concluded that MLP could be used as a functional antioxidant additive in pork droëwors.
- Full Text:
- Date Issued: 2016
The effect of moringa oleifera leaf meal on growth perfomance, gut integrity, bone strenght, quality and oxidative stability of meat from broiler chickens
- Authors: Nkukwana, Tobela T
- Date: 2012
- Subjects: Moringa oleifera , Chickens -- Nutrition , Chickens -- Feeding and feeds , Broilers (Chickens)
- Language: English
- Type: Thesis , Doctoral , PhD (Animal Science)
- Identifier: vital:11820 , http://hdl.handle.net/10353/d1006835 , Moringa oleifera , Chickens -- Nutrition , Chickens -- Feeding and feeds , Broilers (Chickens)
- Description: This study was designed was to determine the effects of additive supplementation of Moringa oleifera leaf meal on growth performance, digestibility, digestive organ size, intestinal integrity, bone ash content and bone breaking strength, as well as meat yield and quality of broiler chickens. A total of 2400 day-old unsexed Cobb-500 broiler chicks were randomly allocated to 5 treatment groups: T1, positive control, 668 g/ton Salinomycin and 500 g/ton Albac; T2, T3 and T4 contained graded levels of MOLM at 1 percent, 3 percent and 5 percent of dry matter (DM) intake, respectively; and T5, a negative control (0 percent additives) in a complete randomized design experiment. Except for week one, FI and FCR was highest (P < 0.05) in T4 birds; while T1 birds had the highest FI in the period of 22 to 27d (P < 0.05). Throughout the production period, birds supplemented with MOLM had the highest BW (P < 0.05) than the birds fed the control diets. Feed intake (FI) and feed conversion ratio (FCR) among treatments was highest (P < 0.05) in T4 birds during the period of 8 to 14 d; and was highest (P < 0.05) for T1 birds in the period of 22 to 27d. Protein efficiency ratio (PER) and energy utilization efficiency (EEU) ratios were statistically significant among treatments (P < 0.05). However, dietary treatments had no effect (P > 0.05) on the weights of the heart, liver, spleen, or the gizzard, although the bursa for T2 birds was the lightest (P < 0.05); while gizzard erosion score was highest in T2 birds. All of the nutrients measured, except for fat, had negative intercepts that were significantly different (P < 0.05) from zero, indicating the presence of endogenous fecal losses. Tibiae length (TL) was highest in T2. The dried defatted weight (DW) was heaviest (P < 0.05) for T3 (11.20 ± 0.347) and T5 (11.08 ± 0.328). A positive correlation (r = 0.667; P < 0.01) between TW and DW was observed. There were no dietary effects on bone breaking strength (BBS), but T1 tibiae had highest resistance to breaking force (T1 > T4 > T3 > T2 > T5). Calcium was highest (P < 0.05) in T1; and lowest inT2 and T5. Phosphorus levels were lowest (P < 0.05) in T1; and highest (P < 0.05) in T5 compared. The highest Ca: P ratio was obtained in T4 (P < 0.05); while the ash percent was highest (P < 0.05) in T1. Drip loss increased as L* values increased; and a negative correlation was observed between L* and pH. On D1, C18: 0 and C22 in T2, while C15:0 was highest in T4. On D1, C20:2, C20:3n6 and C22:6n3 were highest in T2 (P < 0.05); T4 had the highest C18:3n6 (P < 0.05), while C20:2 was highest in T5 (P < 0.05). The P/S ratio on D1 was highest in T4; while n-6/n-3 was highest in T1; and n-3 was highest in T3. On D8, the n-3 was highest in T1 (P < 0.05). Results of the current study show that supplementation of M. oleifera leaf at additive levels of up to 5 percent of the bird’s DMI does have the potential to influence the bird performance without any detrimental effects on nutrient utilization, bird health, bone strength and/or meat quality, which can be concluded that MOLM enhanced the bird’s genetic potential for optimal productivity.
- Full Text:
- Date Issued: 2012