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The performance of the high-oleic Moringa oleifera seed oil (MoO) in deep-frying was evaluated by comparing its frying stability with other conventional frying oils [canola (CLO), soybean (SBO), and palm olein (PO)]. The oils were used as a frying media to fry potato chips for 6 h a day up to a maximum of 5 days. Standard methods for the determination of used frying oil deterioration such as changes in color, viscosity, free fatty acids (FFA), peroxide value (PV), p-anisidine value (p-AV), iodine value (IV), specific extinction (E |cm %233 and 269 nm) and total polar compounds (TPC) were used to evaluate the oils. At the end of the frying period, the change in percent FFA from the initial to final day of frying were as follows SBO (60.0%), PSO (65.0%), MoO (66.6%) and CLO (71.4%) and the change in p-AV and TOTOX value of MoO were found to be significantly lower (P < 0.05) than the rest of the oils tested, followed by PO, with the highest values obtained in CLO and SBO. The levels of conjugated dienes and trienes (E |cm %at 233 and 269 nm) throughout the frying period were lowest in MoO and PO followed CLO, with highest levels found in SBO. The rate of darkening and increase in viscosity were proportional to the frying time for all the oils. PO darkened earlier followed by CLO. At the end of frying period, TPC was significantly (P < 0.05) lower in MoO (20.78%) and PSO (21.23%), as compared to CLO (28.73%) and SBO (31.82%).

The physico‐chemical properties of oil from Carica papaya were determined following extraction with petroleum ether and aqueous‐enzymatic methods. Four commercial enzymes were used for the enzymatic extraction, namely, Termamyl 120 L, Type L (α‐Amylase), Neutrase®0.8 L (Neutral protease), Celluclast®1.5 L FG (Cellulase) and Pectinex®Ultra SP‐L (Pectinase). The melting point of the oil was 9.7–10.5C and showed that there was no significant difference (P > 0.05) between the oil obtained from enzyme and solvent extractions. Generally, the color of the oil was reddish yellow. Solvent‐extracted oil tended to have more yellow and red color (24 Y + 4.0 R) compared to enzyme‐extracted oil (20 Y + 3.0 R). The iodine and the saponification values of the solvent‐extracted oil were found to be 66.0 and 154.7, respectively, while those of the enzyme extracted oil were 66.2–69.3 and 154.2–161.7, respectively. The unsaponifiable matter of the oil extracted using different enzymes ranged between 2.07 and 2.90% and were significantly different (P < 0.05) from that of the solvent‐extracted oil (1.39%). The predominant fatty acid in the oil was oleic acid (72–78%), with some palmitic (12–14%), stearic (4–5%) and linoleic (2.5–3.5%) acids with no significant difference in fatty acid compositions between oil extracted using solvent and enzymes. The main triacylglycerols (TAGs) were sn‐glycerol‐oleate‐oleate‐oleate (OOO) (43.5–45.5%) and 1‐palmitoyl‐dioleoyl glycerol (POO) +stearoyl‐oleoyl‐linoleoyl glycerol (SOL) (29.5–30.5%).

The ability of palm oil (PO) to crystallize as beta prime polymorph has made it an attractive option for the production of margarine fat (MF). Palm stearin (PS) expresses similar crystallization behavior and is considered one of the best substitutes of hydrogenated oils due to its capability to impart the required level of plasticity and body to the finished product. Normally, PS is blended with PO to reduce the melting point at body temperature (37 °C). Lipid phase, formulated by PO and PS in different ratios were subjected to an emulsification process and the following analyses were done: triacylglycerols, solid fat content (SFC), and thermal behavior. In addition, the microstructure properties, including size and number of crystals, were determined for experimental MFs (EMFs) and commercial MFs (CMFs). Results showed that blending and emulsification at PS levels over 40 wt% significantly changed the physicochemical and microstructure properties of EMF as compared to CMF, resulting in a desirable dipalmitoyl-oleoyl-glycerol content of less than 36.1%. SFC at 37 °C, crystal size, crystal number, crystallization, and melting enthalpies (ΔH) were 15%, 5.37 μm, 1425 crystal/μm(2), 17.25 J/g, and 57.69J/g, respectively. All data reported indicate that the formation of granular crystals in MFs was dominated by high-melting triacylglycerol namely dipalmitoyl-oleoyl-glycerol, while the small dose of monoacylglycerol that is used as emulsifier slowed crystallization rate. Practical Application: Most of the past studies were focused on thermal behavior of edible oils and some blends of oils and fats. The crystallization of oils and fats are well documented but there is scarce information concerning some mechanism related to crystallization and emulsification. Therefore, this study will help to gather information on the behavior of emulsifier on crystallization regime; also the dominating TAG responsible for primary granular crystal formations, as well as to determine the best level of stearin to impart the required microstructure properties and body to the finished products.

Moringa oleifera seed oil was extracted using four different types of enzymes to obtain the most efficient extraction parameters. The enzymes used were Neutrase 0.8L (neutral protease), Termamyl 120L, type L (a-amylase), Pectinex Ultra SP-L (pectinase) and Celluclast 1.5L FG (cellulase). These were used either separately or in combination. Individually, Neutrase was found to be the most effective, followed by Termamyl, Celluclast and Pectinex. A combination of the four enzymes was found to be more effective than used separately, with 74% oil recovery. Percent oil recovery for individual enzymes under optimal conditions and with pH adjusted to the individual enzyme's optimum pH were 71.9, 64.8, 62.6 and 56.5 for Neutrase, Termamyl, Celluclast and Pectinex, respectively. Neutrase, Pectinex and the combination of all the four enzymes at 2% (v/w) were found to perform best at 45C, while Termamyl and Celluclast were best at 60C. The physical and chemical properties of the extracted oils such as iodine value (IV) (66.0-67.2 g iodine/100 g oil), free fatty acid (FFA) content (1.13-1.25 as % oleic acid), complete melting points (MPs) (18.6-19.1C) and viscosities (83.1-85.0 cP) except the color were not significantly affected (P Ͼ 0.05) by the type of enzyme used in 4 Corresponding

The main goal of the present work was to assess the mechanism of crystallisation, more precisely the dominant component responsible for primary crystal formations and fat agglomerations. Therefore, DSC results exhibited significant effect on temperature transition; peak sharpness and enthalpy at palm stearin (PS) levels more than 40wt.%. HPLC data demonstrated slight reduction in the content of POO/OPO at PS levels less than 40wt.%, while the excessive addition of PS more than 40wt.% increased significantly PPO/POP content. The pNMR results showed significant drop in SFC for blends containing PS less than 40wt.%, resulting in low SFC less than 15% at body temperature (37°C). Moreover, the values of viscosity (η) and shear stress (τ) at PS levels over 40wt.% expressed excellent internal friction of the admixtures. All the data reported indicate that PPO/POP was the major component of primary nucleus developed. In part, the levels of PS should be less than 40wt.%, if these blends are designed to be used for margarine production.

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Easily perishable soursop (Annona muricata L.) fruit was converted into powder for value‐addition. Soursop puree obtained from fruit pulp that had been treated with different concentrations (0–2% v/w) of Celluclast 1.5 L at fixed (1.5% v/w) concentration of Pectinase Ultra SP‐L were spray‐dried at various inlet temperatures (130–160 °C) after mixing the puree with maltodextrin (20–40% w/w). Multiple responses optimization from Response Surface Methodology (RSM) indicated puree that was pretreated with 1.3% (v/w) cellulase and incorporated with 37% w/w maltodextrin and spray‐dried at an inlet temperature of 156 °C could be transformed into powder that had the following physicochemical properties: moisture content, 2.03% (wb); Aw, 0.18; hygroscopicity, 29.02 g/100g; stickiness, 173.02 g and yield 70.56% of powder. The glass transition temperature (Tg) was found to range between 46.53 and 58.25 °C, indicating the spray‐dried powder was an amorphous material. Surface morphology of the powder particles, viewed using Scanning Electron Microscopy, showed they exhibited spherical in shape and possessed a continuous wall (crust) without surface cracks. Practical applications This work offers an alternative way of reducing wastage in soursop plantation due to short shelf life and perishable properties of soursop fruit. Soursop fruit was transformed to soursop puree without the addition of water by enzymatic–liquefaction. The soursop puree produced by enzymatic pretreatment is suitable to be used as spray drying feed as the puree produced is smooth. This is significant especially to the food processing industry to understand the potential application of enzyme in pretreatment step to liquefy and reduce the viscosity in the production of puree instead of using conventional method (addition of water). Soursop powder was produced by spray drying which is a commercial method in the production of fruit powder. This indicates it is feasible with the spray drying to produce soursop powder that exhibited amorphous particle characteristic. Production of soursop powder also broadens its potential applications in food industry.