Various problems in the quality of acidified milk products surface when pH is lowered. It leads to protein coagulation and agglomeration, protein sedimentation and whey separation that causes low or high viscosity.

In response to such circumstances, local mango peel pectin (MPP) is a recommended stabilizer for whey milk drink and fermented milk products. As a polysaccharide with negative charge, MPP can bind to positively charged protein surfaces, that, therefore, makes it a good stabilizer. Its usage is explored in the research entitled “Quality Improvement of Acidified Buffalo Milk Products Through Stabilization with Locally Produced Mango Peel Pectin”. 

Conducted by researchers Teresita Baltazar, Patrizia Camille Saturno, and Mina Abella, PCC partnered with Philippine Center for Postharvest Development and Mechanization (PhilMech), represented by Dr. Ma. Cristina Gragasin, which provided funds and served as the source of MPP used in the samples. The research was comprised of three component studies that delved on MPP usage in whey drink, fermented whey beverage and yogurt products.

Whey Drink

Both commercial pectin and local MPP were able to prevent protein coagulation and sedimentation in acidified whey drink. Study showed that sedimentation decreases while viscosity increases as the level of pectin increases. Viscosity behavior depends on pectin concentration and also influences the sensory assessment of the product.

Based on the microbial count, the whey drink samples conformed with the FDA Microbiological Standards for non-alcoholic beverages. It was found that acidified whey drink can last 4 weeks at ambient temperature.

Fermented Whey Beverage

It was found that lactic acid fermentation decreases lactose content in whey. The pH level was also reduced. Moreover, the longer the alcoholic fermentation, the higher the increase in alcohol (ethanol) content and an evident decrease in total soluble solids. Mango peel pectin was found to be effective in preventing sedimentation in fermented whey beverage.

Compared to natural flavoring, it was found that artificial flavoring has a higher score in purchase intent and general accessibility despite having no differences between the samples. The cost of fermented whey beverage is Php34.03 per 350mL.

Yogurt Products

In this study, MPP was used to prevent syneresis or wheying-off in set and yogurt drink samples since it gives an undesirable effect on quality.  It was found that treatments in set and yogurt drink with no pectin experienced syneresis on the 15th day while samples with MPP were whey-free. By using MPP, which has a great water-holding capacity, it creates a three-dimensional network in milk while it holds maximum water which leads to the prevention of syneresis and also results in an increase in viscosity in yogurt products. However, specific high levels of MPP have an effect on the color of set and yogurt drink.

Overall, using MPP to improve the quality of acidified buffalo milk products through stabilization was found to be effective in this study. Aside from the prevention of sedimentation and syneresis, it also improves the quality in terms of appearance, viscosity and mouthfeel of acidified milk products.