Extraction, Partial Purification and Utilization of Milk Coagulating Enzyme from Kiwifruit (Actinidia Deliciosa) in Fresh Cheesemaking

Abstract

The study aimed to determine the potential of kiwifruit milk clotting enzyme in cheesemaking. The kiwifruit crude enzyme, extracted with sodium phosphate buffer (pH 7.0), was partially purified by 30-80% ammonium sulfate precipitation. 50% ammonium sulfate saturation exhibited maximum milk clotting activity (MCA), along with 1.56 purification fold, and 78.84% activity recovery. From SDS-PAGE analysis, the partially purified protease showed two bands with a molecular mass of 24 kDa and 23 kDa respectively. The optimum conditions (temperature and pH of milk) for a minimum time of coagulation (TOC) and maximum MCA were determined by response surface methodology (RSM). From the numerical optimization study, the optimum conditions for cheesemaking were pH 6.5 and temperature 55oC, having 0.94 desirability. The cheese prepared by kiwifruit protease had significantly (p<0.05) higher moisture, ash, calcium content, and yield than rennet cheese, while significantly (p<0.05) lower fat content and acidity were observed in kiwifruit protease coagulated cheese. However, a non-significant (p>0.05) difference in protein content was obtained between both cheeses. This study highlighted that kiwifruit protease has the ability to be used as an efficient milk clotting enzyme in fresh cheesemaking.

Utilization of Partially Purified Milk Clotting Protease from Ginger Rhizome in the Manufacturing of Fresh Cheese

“…The difference found in the ash content between the cheeses made by two coagulants was significant (p<0.05). Higher ash content was observed in cheese B, which is in accordance with the findings of Kheir et al (2011), Khan & Masuq (2013) and Maskey & Karki (2022). The ash content of cheese, which is represented by its mineral content, depends on the concentration of salt used during cheese brining.…”

“…Greater value of fat content was observed in cheese A. Similar findings in the cheeses manufactured by using chymosin and kiwifruit protease were expressed by Maskey & Karki (2022). The loss of fat during whey drainage might be the reason for the lower fat level in cheese B.…”

“…In partial purification of bromelain from pineapple core, Gul et al ( 2021) observed a greater purification fold (2.28) and recovery (215.25%). However, a lower purification fold (1.56) and recovery (78.84%) of kiwifruit protease were reported by Maskey & Karki (2022). The reason behind the variation in both purification fold and recovery might be due to the difference in plant species, plant growth conditions, fruit maturity, temperature and ionic strength of extraction buffer, presence of contaminants and inhibitors, as well as protease stability.…”

“…Similar finding in the purification of ginger (Zingiber officinale Roscoe) rhizome protease was expressed by Nafi' et al (2013) and Gagaoua et al (2015). Maskey & Karki (2022) also highlighted the highest activity of kiwifruit (Actinidia deliciosa) protease precipitated with 50% (NH 4 ) 2 SO 4 . At greater (NH 4 ) 2 SO 4 concentration, the irreversible denaturation of protease might take place, whereas at lower concentration the O 4 2ions might not affect the hydrophobic protease surface.…”

“…Several researches on milk coagulating ability of plant proteases have been conducted. The examples of such plants include kiwifruit (Actinidia deliciosa) (Nicosia et al, 2022;Maskey & Karki, 2022), papaya (Carica papaya) (Rana et al, 2017;Maskey & Shrestha, 2020), pineapple (Ananas comosus) (Bahmid, 2013;Kartawiria et al, 2019), sodom apple (Calotropis procera) (Abebe & Emire, 2020;Silva et al, 2020), cardoon (Cynara cardunculus) (Gomes et al, 2019;Folgado et al, 2020), trompillo (Solanum elaeagnifolium) (Gutiérrez-Méndez et al, 2019;Nájera-Domínguez et al, 2022), doda paneer (Withania coagulans) (Khan & Masuq, 2013;Nazish et al, 2022) and anjeer (Ficus carica) (Fguiri et al, 2020;Hachana et al, 2021). In addition to milk coagulation abilities, plant proteases also contain antioxidant properties, and a high concentration of bioactive substances (Gupta et al, 2015).…”