Table 2. Processing of BSG and Application in Food Products.

upcycling strategy	process conditions	food product	proportion of BSG incorporated	main finding(s)	ref
enzyme treatment and fermentation	hydrolysis with an enzyme mixture for 12–24 h at 55 °C followed by fermentation with Lactiplantibacillus plantarum F10 and/or Lacticaseibacillus rhamnosus LGG for 8–24 h at 25–27 °C (patent no. WO 2018/033521 A1)	bread	4–18% of baker’s flour replaced with BSG or fermented BSG (fBSG) (w/w) to reach “source of fiber” (3 g/100 g fiber) and “high fiber” (6 g/100 g fiber) claims	inclusion of fBSG in bread resulted in increased specific volume, reduced crumb hardness, increased microbial shelf life, and a slower release of reducing sugars over time during in vitro starch digestion compared to control BSG	(35)
enzyme treatment and fermentation	hydrolysis with an enzyme mixture for 12–24 h at 55 °C followed by fermentation with Lactiplantibacillus plantarum F10 and/or Lacticaseibacillus rhamnosus LGG for 8–24 h at 25–27 °C (patent no. WO 2018/033521 A1)	pasta	2.00–14.96% of flour replaced with BSG or fermented BSG (fBSG) (w/w) to reach “source of fiber” (3 g/100 g fiber) and “high fiber” (6 g/100 g fiber) claims	inclusion of fBSG reduced the glycemic index of pasta compared to control BSG	(17)
fermentation	10 g of ground, autoclaved BSG mixed with 50 mL of sterile water, inoculated with 106 CFU/g of Bacillus subtilis WX-17 and fermented at 37 °C for 72 h; samples were filtered, and the supernatant was collected and analyzed	beverage	16.7% (w/v)	fermentation produced a nutritious beverage (liquid phase of fermentation) with increased levels of 13 amino acids, higher antioxidant content, and increased phenolic compounds	(79)
fermentation and protein extraction	BSG fermented with Rhizopus anisospores (107 spores/mL) at 37 °C for 3 days, freeze-dried, ground into powder and sieved (sieve size 400 μm); proteins extracted by ethanolic-alkali extraction	mayonnaise	BSG protein (BSGP) and fermented BSG protein (fBSGP) mixed with whole egg and added to mayonnaise formulation (10%); ratio of BSGP or fBSGP to whole egg: 40% (f)BSGP + 60% whole egg; 60% (f)BSGP + 40% whole egg; 100% (f)BSGP	fBSGP displayed superior emulsifying stability, water/oil binding capacity, foaming capacity, and antioxidant activity to BSGP; fBGSP demonstrated improved emulsion stability in terms of creaming, microstructure, and viscosity in mayonnaise	(68)
fermentation	UHT skim milk supplemented with BSG flour, inoculated with Streptococcus thermophilus TH-4 and Lacticaseibacillus paracasei subsp. paracasei F-19 and fermented at 37 °C until pH 5.4 was reached	fermented milk	1% (w/v)	BSG did not influence fermentation kinetics or microbial population numbers, but enhanced the survival of S. thermophilus TH-4 against in vitro simulated gastrointestinal stress	(72)
fermentation	BSG filtered and liquid fraction (100 μm) collected (LBSG), mixed with a commercial soy drink (SoD) and fermented with strains of Lactiplantibacillus plantarum and Lactococcus lactis at 30 °C for 18 h	yogurt	20:80 LBSG to SoD (% v/v)	inclusion of 20% LBSG resulted in a product with a protein content, acidity level, and texture/sensory characteristics similar to that of a dairy yogurt	(71)
enzyme treatment and fermentation	ground BSG homogenized with water at a 60:40 ratio, supplemented with xylanase (Depol 761P, 100 nanokatal (nkat)/g) and incubated at 50 °C for 5 h; enzyme-treated BSG inoculated with 107.5 CFU/g of L. plantarum PU1 and incubated at 37 °C for 24 h	pasta	15% of semolina (w/w) replaced with BSG or fermented BSG (fBSG)	compared to control BSG, the use of enzyme treated and fermented BSG resulted in pasta with higher protein digestibility and quality indices (biological value, protein efficiency ratio, essential amino acid index, and nutritional index), improved technological and sensorial characteristics, and increased antioxidant activity	(70)
fermentation and enzyme extraction	BSG adjusted to 55% moisture (w/w) with water, inoculated with 107 spores/g of Aspergillus awamori IOC-3914 and incubated at 30 °C for 96 h (air water saturation of 90%)	bread	20% of wheat bran (w/w) replaced with fermented BSG (48 h) and 14% of water (v/v) replaced with crude enzymatic extract of fermented BSG	bread containing fermented BSG contained 198% more soluble ferulic acid than control bread, but had a decreased volume and higher density	(69)
fermentation	moisture content of substrate (stale sourdough breadcrumbs mixed with BSG) adjusted to 40% with distilled water, inoculated with 2.7 × 106 and 1.4 × 106 of Neurospora intermedia CBS 131.92 and Rhizopus oryzae CCUG 28,958, respectively, and incubated at 35 °C for 6 days	stale sourdough bread	0–20% (w/w)	fermentation of stale sourdough bread mixed with 6.5% or 11.8% BSG by N. intermedia or R. oryzae resulted in a product with textural properties similar to a commercial soybean burger	(80)
enzyme treatment	sheared and pH-adjusted BSG incubated with 75 μL g–1 BSG dry weight of each carbohydrase (Biocellulase A, Bioglucanase FS2000 and Bioglucanase HAB) at 50 °C for 1 h; pH of the suspension was adjusted to pH 9.3 and suspension was incubated at 50 °C for 2 h with Alcalase 2.4 L (2%, v/w, BSG protein) followed by the addition of Bioprotease FV (1% v/w, BSG protein) and incubation for 2 h at 50 °C	muffins	5, 10, 15% (w/w)	inclusion of enzyme-treated BSG resulted in muffins with higher height, darker color, and decreased hardness compared to the control	(62)
fermentation	BSG substituted with sucrose (10% w/w), inoculated with 106 CFU/g of Weissella confusa A16 and incubated at 25 °C for 24 h	bread	33% (w/w)	presence of dextran and maltosyl-isomaltooligosaccharides along with the increased protein and fiber levels in breads containing fermented BSG resulted in higher free amino acid bioaccessability and a positive effect on gut microbiota functionality	(76)
fermentation	BSG mixed with milk, pasteurized at 90 °C for 15 min, cooled to 38–43 °C, inoculated with 0.05% (w/w) of microbial culture (Streptococcus thermophilus, Lactobacillus delbreuckii subsp. bulgaricus, Lactobacillus acidophilus, and Bifidobacterium lactis) and incubated at 43 °C until a pH of 4.3–4.8 was reached	yogurt	BSG mixed with milk at ratios of 0:100, 5:95, 10:90, 15:85, and 20:80 (BSG/milk; w/w),	inclusion of BSG decreased the fermentation time, maintained the flow behavior and stability of the yogurt, and supported the survival of LAB during the 14 days chilled storage	(56)
enzyme treatment	BSG mixed with water at a ratio of 1:10, incubated without protease treatment (BSGP-C), with 0.5% Protamex (BSGP-P), or with 0.5% Protamex and 0.1% Flavourzyme (BSGP-PF) at 50 °C for 3 h and heated to 90 °C for enzyme inactivation	coconut-based yogurt	BSG mixed with water-soluble coconut extract (WSCE) at a ratio of 1:9 (w/w)	use of BSG derivatives resulted in yogurt alternatives with a less dense fat distribution, a more homogeneous matrix, and a 3-fold higher lactic acid concentration	(64)
enzyme treatment	BSG treated with protease (Alcalase) and carbohydrase (Cellulclast 1.5 L at two levels (0 and 0.1% w/w) according to a central composite design to produce BSG flour (FBSG)	bread	20% of wheat flour (w/w) replaced with FBSG	FBSG bread had a higher fiber content, total polyphenol content, and antioxidant activity than the control bread, but a decrease in specific volume and an increase in rubberiness was observed	(63)
fiber extraction	washed, defatted BSG gelatinized with 0.6% Termamyl at 95 °C for 1 h, washed four times with hot distilled water (100 °C) and cooled at room temperature; residues were washed with 99.9% ethanol (60 °C), filtered, and dried	chicken patties	1, 2, 3, 4% of BSG dietary fiber extract (w/w)	addition of 3% BSG dietary fiber extract resulted in the lowest cooking loss, no significant difference in protein solubility, no change in patty diameter and the highest sensorial acceptability	(81)
fiber extraction	washed, defatted BSG gelatinized with 0.6% Termamyl at 95 °C for 1 h, washed four times with hot distilled water (100 °C) and cooled at room temperature; residues were washed with 99.9% ethanol (60 °C), filtered, and dried; BSG pre-emulsion prepared by combining carboxymethyl cellulose, ice, and BSG dietary fiber extract and homogenizing for 5 min	chicken sausages	20, 25, 30% of pork fat replaced with BSG pre-emulsion (w/w)	inclusion of BSG pre-emulsion improved the hardness, chewiness, and gumminess of the reduced-fat chicken sausages, while having no influence on cohesiveness; addition of BSG pre-emulsion up to 25% had no significant difference in acceptability of the chicken sausages	(49)