Table 1.

Results on the applicability of HXT on meat and its effect on product quality.

Extract Form	Concentration (ppm)	Meat Product	Test Setup	Tested Parameters	Results	Reference
Commercial	10,000 30,000	Ground beef patties	Ground beef was mixed with extract and inoculated with E. coli (107 cfu/g). Uniform patties were formed, cooked and shock-cooled.	Total viable count	It was enhanced cell count reduction (3% survivors detectable)	[53]
				Amine quantification	Reduction of amine formation (50.6%)
Commercial	100	Pork meat with W1/O/W2 emulsions	Ground pork meat and fat were mixed with W1/O/W2 emulsions and chia oil. Emulsions were vacuum packaged and keep in chilled storage (4 °C) until analyses on the 1st, 7th, 19th, 28th and 39th days.	Light microscopy	Particle size in samples with HXT was higher (p < 0.05)	[54]
				Antioxidant activity: DPPH	Chia oil presence in meat samples increased oxidation, however, HXT acted as antioxidant (8%).
				Lipid oxidation (TBARs)	HXT presence in meat samples reduced lipid oxidation by more than 50%.
Concentrate	100.23	Fermented sausages	During the drying process fermented sausages were dipped in extract solutions (2.5–5%) for 1 min at 20 °C and were continued drying.	Total viable count	No differences	[55]
				Lactic acid bacteria	No differences
				Micrococci	Growth reduction affected volatile compound profile
				Yeast	No significant differences
				Moulds	Reduction of species
				pH	No significant differences
				Water activity	No significant differences
				Lipid oxidation (TBARs)	Reduced values (12–38%)
				Volatile compounds	Reduces volatile compounds from microbial esterification and lipid oxidation
				Sensory attributes (colour)	Redness increased
Commercial	100, 200, 400	Lamb meat patties	Minced lamb meat enriched in omega-3 fatty acids (with fish oil) was mixed with natural extracts and stored in high-oxygen modified atmosphere packs for up to 9 days at 4 °C.	In vitro antioxidant activity (ORAC and FRAP)	ORAC: No significant differences	[56]
					FRAP: antioxidant activity increases with extract presence
				Colour (CIELab)	Lightness (L*) increased in samples without extract by changes in muscle proteins.
					Significant differences between samples at day 3, 6 and 9 of storage.
				Lipid oxidation (TBARs)	No significant differences
				Protein oxidation (thiol and carbonyl groups)	Natural extracts improvement texture but it alteration odour and flavour.
				Sensory analysis
Concentrated, undefined	75, 150	Pork sausages	Ground pork (50/50 - meat/fat) was minced and mixed with salt and phenols. Mix was stuffed into 40-mm diameter bovine casings, were left to drip at 15 °C for 6 h and stored without packaging alternating fluorescent light (12 h dark and 12 h light) at 2 °C for 14 days. After, sausages were cooked, stored 72 h at 4 °C and frozen until analysis (80 °C)	Nutritional composition	No differences	[57]
				pH	No differences
				Cooking loss	No differences
				Diacylglycerols	Phenols had an inhibitory effect on microorganisms and a reduction in lipolytic activity.
				Lipid oxidation (TBARs)	Oxidation was reduced (>40%) as TBARs as POV. But there are no differences in COPs.
				Peroxide value (POV)
				Cholesterol oxidation products (COPs)
				Sensory analysis	Phenols presence was valorated worst by panellists.
Commercial 1. HXT 23% from olive waters 2. HXT 7% from olive leaves 3. HXT 7% from olive waters	50	Chicken sausages	Pork fat and chicken meat were minced and mixed with walnuts, EVOO and three HXT extracts. Samples were cooked for 3 h at 72 °C, packaged in MAP (10% O2/20% CO2/10% N2) and stored at 4 °C for 21 days.	Nutritional composition	No differences	[21]
				Colour (CIELab)	L* and b* were lower in samples with HXT and EVOO, while a* was higher
				Cooking loss	Cooking loss values were higher in samples with HXT
				Lipid oxidation (TBARs)	In samples with HXT TBARs value was lower and in samples with HXT and EVOO, lipid oxidation was 71% lower than control.
				Protein oxidation (thiol groups)	HXT reduced protein oxidation between 13–25%.
				Scanning electron microscopy	Sausages incorporated HXT showed different structures.
				Sensory analysis	Samples with HXT 7% from olive water was accepted, while other samples with HXT presented lowest acceptability.
Commercial, 7% from olive waters	50	Chicken Frankfurters	Back fat and chicken meat were minced and mixed with walnuts, EVOO and HXT. Samples were cooked for 3 h at 72 °C, packaged in MAP (10% O2/20% CO2/10% N2) and stored at 4 °C for 21 days.	Nutritional composition	No differences	[20]
				Mineral content	Ca, K, Fe, Mg, P, Mn and Zn concentrations were higher in samples with HXT.
					No differences
				Fatty acid profile. Sensory analysis	Extracted flavour and odour parameters were increased in samples with HXT but it was accepted by panellists.
Olive cake applied in chicken feed	4.6 9.5	Chicken meat	297 chickens were feeding until 21 days of age with three treatments: basal diet, diet supplemented with 82.5 g/kg olive phenols and diet supplemented with 165 g/kg olive phenols. Chickens were weighed at 28, 35 and 42 days of age and slaughtered at 42th. Carcasses were maintained at −20 °C for three months until consumption and at −80 °C for other analyses.	Chicken weight	The chicken weight was higher	[58]
				Colour (CIELab)	L* and b* was higher while a* was lower
				Cooking loss	No differences
				Nutritional composition	No differences
				pH	No differences
				Lipid oxidation (TBARs)	Lipid oxidation was lower
				Antioxidant capacity (DPPH)	Samples with HXT showed a high antioxidant capacity
				Sensory analysis	No differences, so HXT did not alter the sensory quality.