Development of value-added butter through the addition of green tea (Camellia sinensis L.) extract

The present work highlights the potential production of value-added butter with enhanced nutritional and microbiological properties through the addition of 2 - 10% (w/w) green tea (Camellia sinensis L.) extract. The results revealed no significant difference in the moisture content (13 - 14% w/w) of all the butter samples. However, an increase in the amount of green tea extract resulted in a significant increase (p < 0.05) of the ash content (0.00 - 1.00%) and redness (a* value, 4.92 - 6.93), while both the lightness (L* value, 150.65 - 145.74) and yellowness (b* value, 54.45 - 50.30) of the butters significantly decreased (p < 0.05). Furthermore, the green tea butters (GTBs) exhibited significantly (p < 0.05) higher antioxidant properties in terms of total phenolic content (0.07 - 0.10 vs. 0.01 GAE% w/w db) and DPPH activity (7.27 - 13.94% vs. not detected) as compared to the control butter. After six weeks of storage, in relation to the control butter, the GTBs recorded significantly lower (p < 0.05) peroxide value (2.13 vs. 0.88 mEq/kg), total plate count (1.11 × 104 vs. 2.42 × 103 CFU/g), and yeast and mould count (2.02 × 103 vs. 6.05 × 102 CFU/g), but produced a significantly higher (p < 0.05) amount of acid value (0.56 vs. 1.36 mg KOH/g fat). The incorporation of up to 6% (w/w) green tea extract did not compromise the sensory acceptance of the GTBs. The overall result indicated that green tea extract can be used as a natural food additive, antioxidant, and preservative in butter

การสังเคราะห์สตรัคเจอร์ไตรกลีเซอร์และฟอสโฟลิปิดจากน้ำมันปาล์มและน้ำมันปลาทูน่าโดยเอนไซม์ไลเปสตรึงรูปและฟอสโฟไลเปส

Thesis (Ph.D., Biotechnology)--Prince of Songkla University, 200

Lipid Oxidation Changes of Arabica Green Coffee Beans during Accelerated Storage with Different Packaging Types

The storage conditions of green coffee beans (GCBs) are indispensable in preserving their commercial value. In Thailand, coffee farmers and roasters typically store GCBs for six months to a year before roasting. However, the beans undergo oxidation during storage, influencing both quality and taste. This study investigated changes in GCB lipid oxidation under different accelerated storage conditions (30 °C, 40 °C and 50 °C with 50% RH) and packaging, i.e., plastic woven (PW), low-density polyethylene (LDPE) and hermetic/GrainPro® (GP) bags. Samples were collected every five days (0, 5, 10, 15 and 20 days) and analyzed for lipid oxidation parameters including acid value (AV), free fatty acids (FFA), peroxide value (PV), ρ-anisidine value (PAV), total oxidation value (TOTOX), thiobarbituric acid reactive substances (TBARS), moisture content (MC), water activity (aw) and color. Primary oxidation was observed, with AV, FFA and PAV gradually changing during storage from 1.49 ± 0.32 to 3.7 ± 0.83 mg KOH/g oil, 3.82 ± 0.83 to 9.51 ± 1.09 mg KOH/g oil and 0.99 ± 0.03 to 1.79 ± 0.14, respectively. Secondary oxidation changes as PV and TBARS were reported at 0.86 ± 0.12 to 3.63 ± 0.10 meq/kg oil and 6.76 ± 2.27 to 35.26 ± 0.37 MDA/kg oil, respectively, affecting the flavor and odor of GCBs. Higher storage temperature significantly influenced a lower GCB quality. GP bags maintained higher GCB quality than LDPE and PW bags. Results provided scientific evidence of the packaging impact on oxidation for GCB under accelerated storage