Chemical and in vitro evaluation of Leucaena (Leucaena leucocephala) Leaves as a Substitute of Alfalfa (Medicago sativa L.) with/without Rejected Green Banana Fruits (Musa paradisiaca)

Leucaena leaves and rejected green banana fruits can be promising to cope with feed gaps in arid and semi-arid Mediterranean regions. The present study evaluated the feeding value and secondary active compounds of Leucaena leaves and rejected green banana fruits for ruminants using a semi-automated gas production (GP) system. Comparisons were made with the traditional feeds as alfalfa, and Dichanthium spp. grass hay. Analysis of HPLC was performed for the feed ingredients to characterize the main phenolic components. The in vitro evaluation was carried out for the experimental feed ingredients and diets. Four diets were formulated as the first diet consisted of alfalfa and grass hay at a ratio of 35:65 (AG), the second diet composed of alfalfa, grass hay, and green banana fruits at a ratio of 35:55:10 (AGB), third and fourth diets were prepared by replacing alfalfa in AG and AGB with Leucaena leaves to be LG and LGB, respectively. Leucaena leaves showed a high content of valuable phenolic components that have antioxidant and anti-inflammatory properties, such as gallic acid, ellagic acid, and naringenin. Moreover, Leucaena leaves and diet had higher crude protein, total phenols, and total tannins than alfalfa, which was reflected on the chemical composition of diets, and recorded the lowest total accumulative GP at 24 hours leading to low CH4 and CO2 production. Banana fruits recorded the lowest ruminal pH, ammonia concentration, and degraded neutral detergent fiber, compared to other feed ingredients, while it had the highest GP and degraded organic matter. Therefore, it is highly recommended to use Leucaena leaves in animals’ diets with/without rejected green banana fruits as an alternative feed resource with potential environmental and animal health benefits.

Physicochemical Characteristics, Microstructure and Health Promoting Properties of Green Banana Flour

This study aimed to investigate the proximate composition, mineral content, functional properties, molecular structure, in vitro starch digestibility, total phenolic content (TPC), total flavonoid content (TFC) and antioxidant activity (DPPH, FRAP) of green banana flour (GBF) cultivars grown in South Africa. With proximate composition, Finger Rose and Pisang Awak had the highest protein (4.33 g/100 g) and fat (0.85 g/100 g) content, respectively. The highest ash content (3.50 g/100 g) occurred with both Grand Naine and FHIA-01 cultivars. Potassium and copper were the most abundant and least minerals, respectively. Pisang Awak cultivar had the highest water absorption capacity (67.11%), while Du Roi had the highest swelling power (0.83 g/g) at 90 °C. Scanning electron microscopy (SEM) images revealed that starch granules from all GBF cultivars were irregular in shape and they had dense surfaces with debris. All the GBF cultivars had similar diffraction patterns with prominent peaks from 15°–24° diffraction angles. The resistant starch (RS) and amylose content of the FHIA-01 cultivar indicates that the GBF has the potential to lower risks of type 2 diabetes and obesity. The highest TPC, TFC and antioxidant activity occurred with the Grande Naine cultivar. Based on their functional characteristics, the Grand Naine and FHIA-01 GBF cultivars could potentially be used as raw materials for bakery products as well as for the fortification of snacks.

Development of a cake rich in resistant starch with good sensory acceptance

The objective of this study was to develop a cake rich in resistant starch, with green banana flour (GBF), of good sensory acceptance. In step 1, four cake formulations were prepared with increasing concentrations of GBF and evaluated for acceptability and purchase intention. In step 2, four new formulations were made by modifying the most accepted formulation in step 1, in addition to the formulation without GBF (control). The resistant starch content, proximate composition, total calorific value, and sensory acceptance data were obtained. The formulation with cocoa powder and dried banana (E1F4) achieved 97.78% overall acceptance and higher purchase intent. In step 2, the formulations with 14% and 18% GBF were the most accepted for flavor, texture/softness, and overall acceptance. Adding the categories of “would certainly buy” and “would probably buy”, 53.33% of consumers would buy the cake with 14% GBF and 48.89% would buy the cake containing 18% GBF. The incorporation of GBF increased the resistant starch contents of the formulations as compared with the control. Ash content was highest in the formulation with 26% GBF (2.22%) and lipid content in the control formulation (11.58%). The treatments did not differ in terms of moisture content. Protein content decreased as the GBF content in the formulations was increased. The total dietary fiber content of the formulations was 9.30%. Carbohydrate content and calorific value also did not vary. The mean values of L*, a*, b*, C*, and h* showed that the cakes had an intense dark brown color. In conclusion, the addition of 14% and 18% GBF to the cake resulted in a product of high sensory acceptance, with high purchase intent, a resistant starch content 7.21 and 8.34 times higher than those in the control cake.

Green Banana (Musa acuminata AAA) Wastes to Develop an Edible Film for Food Applications

In this study, edible packaging based on discarded green banana (Musa acuminata AAA) flour (whole banana and banana peel flours) was developed for food applications. Films were characterized in terms of film-forming ability, mechanical, barrier, thermal, microbiological, and sensory properties. The film forming solutions were studied for rheological properties. Two formulations were selected based on their film-forming ability: whole banana flour (2.5%), peel flour (1.5%) and glycerol (1.0 %, F-1.0 G or 1.5%, F-1.5 G). Adding 1.5% plasticizer, due to the hygroscopic effect, favored the water retention of the films, increasing the density, which also resulted in a decrease in lightness and transparency. Water activity shows no difference between the two formulations, which were water resistant for at least 25 h. DSC results showed a similar melting temperature (Tm) for both films, around 122 °C. Both films solutions showed a viscoelastic behavior in the frequency spectrum, being the elastic modulus greater in F-1.0 G film than F-1.5 G film at low frequency. F-1.0 G film was less firm, deformable and elastic, with a less compact structure and a rougher surface as confirmed by AFM, favoring a higher water vapor permeability with respect to F.1.5 G film. Microorganisms such as Enterobacteria and Staphylococcus aureus were not found in the films after a period of storage (1 year under ambient conditions). The F-1.0 G film with added spices (cumin, oregano, garlic, onion, pepper, and nutmeg) was tested for some food applications: as a snack (with or without heat treatment) and as a wrap for grilled chicken. The performance of the seasoned film during chilled storage of chicken breast was also studied. Sensory evaluation showed good overall acceptability of all applications. In addition, the chicken breast wrapped with the seasoned film registered lower counts (1-log cycle) than the control (covered with a polystyrene bag) and the film without spices. Green banana flour is a promising material to develop edible films for food applications.