Table 2.
Strategies to valorize of acid whey.
| Source | Research | Product | Method | Strain/enzyme | Key findings |
|---|---|---|---|---|---|
| (10) | Acid whey metabolomics | Metabolic profile | Analytical | - | Acid whey has a rich metabolic composition |
| (120) | Formulating ranch dressing | Formulating ranch dressing by replacing buttermilk with Yogurt Acid Whey (YAW). No lactic acid was added (lactic acid is naturally present in YAW) |
Food technology | - | Up to 60% of buttermilk can be replaced by acid whey |
| (53) | GOS synthesis | GOS | Microbial/enzymatic | Cryptococcus laurentii, Aspergillus oryzae | Acid whey as substrate for GOS synthesis |
| (121) | prebiotic GOS | Prebiotic galacto-oligosaccharides production from acid whey | Enzymatic | β-galactosidases (from Kluyvero-myces lactis and Aspergillus oryzae) and one novel, in-house produced (from Thermothielavioi-des terrestris), | Efficient, cost-effective production of valuable prebiotics from acid whey. The maximum GOS yield was 25.7% when using concentrated acid whey with 20% lactose content and the enzyme from T. terrestris. |
| (31) | Production of Polyhydroxybu-tyrate (PHB) by use of Recombinant Escherichia coli LSBJ | Polyhydroxybuty-rate (bioplastic) | Microbio-logical | Recombinant Escherichia coli LSBJ | Bioconversion of acid whey (AW) to PHB |
| (29) | β-galactosidase | Biocatalysis | Enzymatic | LAB, Bifidobacterium spp. | LAB strains assessed for enzyme activity in acid whey |
| (6) | Fermented beverages based on processing of acid whey. | Fermented probiotic beverages The production process included combining pasteurized acid whey with UHT milk, unsweetenedcondensed milk or skim milk powder-introduced milk to enrich casein content and obtain a product with characteristics similar to that of fermented milk drinks. |
Microbiolo-gical |
Lactobacillus acidophilus LA-5 or Bifidobacterium animalis ssp. lactis BB-12 |
Acid whey is a suitable base for functional beverages. L. acidophilus provides more acidity of beverages in comparison with B. animalis. |
| (12) | Functional ingredients for yogurt | Acid whey protein concentrate after neutralization by food-grade ammonium hydroxide, and then ultrafiltration and diafiltration. | Technolo-gical | — | Whey protein concentrate is used for yogurt making, stable sensory and physicoche-mical properties |
| (25) | GOS | GOS from acid whey | Enzymatic | β-galactosidase from Aspergillus oryzae and Kluyveromyces lactis Trichoderma terrestris |
Enzymes from Aspergillus oryzae and Kluyveromyces lactis, Trichoderma terrestris have thermostable and acid pH-stable β-galactosidase. |
| (13) | Bioenergy | Medium-chain carboxylic acid | Microbio-logical | Microbial composition | Bioconversion of acid whey |
| (64) | Probiotic beverage | Whey and pineapple juice drink | Microbio-logical | Lactobacillus acidophilus, Bifidobacterium bifidum | Probiotic beverage with good sensory properties |
| (4) | Functional beverage | Fermented beverage | Microbio-logical | LAB | Probiotic potential and antioxidant properties |
| (29) | β-galactosidase activity | Hydrolysis of acid whey | Microbiolo-gical/Enzy-matic | LAB strains | Acid whey valorization using LAB enzyme potential |
| (3) | Fermented probiotic beverage | Fermented probiotic beverage | Microbio-logical | LAB and yeast | Enhanced antimicrobial and antioxidant properties |
| (23) | Functional beverage | Beverage based on acid whey | Microbio-logical | Brettanomyces claussenii | Lactose conversion |
| (9) | Review of acid whey benefits | Multiple functional foods | Review | - | Acid whey has health potential and industrial uses |
| (2) | Bioactive peptides | Functional peptides | Microbio-logical | Streptococcus thermophilus | Biopeptides |
| (27) | β-galactosidase optimization | Milk and whey processing | Enzymatic | β-galactosidase (acid- and cold-tolerant) | Enzyme suitable for acidic whey conditions |
| (49) | Whey spirit production | Fermented acid whey spirits | Microbio-logical/ Distillation | Fermenting yeast strains | Characterized volatile compounds during distillation stages |
| (22) | Membrane processing | Treated acid whey | Technolo-gical | — | Electrodialysis and nanofiltration alter whey composition |
| (119) | Mineral removal from acid whey | Calcium and lactate extraction | Technolo-gical | — | Electrodialysis effective in adjusting mineral content |
| (7) | Chemical conversion | 5-HMF and levulinic acid | Chemical / Thermoche-mical | — | Optimized synthesis from acid whey and lactose |
| (47) | Exopolysaccharide production in whey | Iron-complexing EPS | Microbio-logical | Lactic acid bacteria | LAB produce EPS in acid whey with iron-binding properties |
| (122) | Whey fermentation promoters | Genetic regulation insights | Microbio-logical | — | New regulatory promoters discovered in acid whey fermentation |
| (16) | Value of acid whey stream | Functional ingredients | Review | — | Acid whey is becoming more valuable than the main dairy product |
| (19) | Microbial and enzymatic valorization | Nutraceuticals: bioactive peptides, prebiotics, exopolysaccharides, organic acids, bacteriocins, isoflavone aglycones; and industrially important enzymes: β-galactosidase, protease, and amylase. Whey enriched with bioactive compounds can be utilized for the functional and nutritional enhancement of foods and the development of novel functional foods with health beneficial effects. | Microbial and enzymatic | LAB, enzymes | Acid whey enriched with bioactive compounds can be utilized for the functional and nutritional enhancement of foods and the development of novel functional foods with health beneficial effects. |
| (26) | GOS synthesis from whey | Galactooligosaccharides | Enzymatic | lactases from Aspergillus oryzae and Kluyveromyces lactis | Both acid and sweet whey are suitable for GOS production |
| (24) | Cosmetic biotechnology | Innovative cosmetic product for hair based on lactoserum | Technolo-gical | — | Whey based concentrates in cosmetics |
| (20) | Composition analysis | Acid whey from Greek yogurt (GAW), acid whey from cottage cheese (CAW), and milk permeate (MP). | Analytical | - | Composition data of coproduct streams: acid whey from Greek yogurt (GAW), acid whey from cottage cheese (CAW), and milk permeate (MP). |
| (34) | Membrane technology applications | Dairy coproducts | Techno-logical | — | Membrane processes used for treating acid whey |
| (32) | Historical and future outlook | Acid whey | Review | — | Trends and possibilities for whey valorization |
| (11) | Engineering the optimum pH galactosidase | Glycoside hydrolase | Engineering | Aspergillus oryzae | Y138F and Y364F mutants exhibited better hydrolytic ability than lacA in milk lactose hydrolysis. |
| (28) | GOS | GOS | Enzymatic/microbio-logical | Aspergillus oryzae galactosidase, Kluyveromyces marxianus and Saccharomyces cerevisiae cells | Reacted medium without nutrient supplementation (raw GOS) was fermented with Kluyveromyces marxianus cells obtaining GOS of 95% purity containing mostly tri- and tetrasaccharides with total recovery of GOS after 24 h. |