Question

Optimum temperature and period of ripening of cream for butter manufacture is

• A. 28 °C for 10-15h
• B. 15 °C for 15-16 h
• C. 21 °C for 15-16 h
• D. 32 °C for 10-15 h

Hint:

Butter Manufacturing Parameters: Cream Ripening = $21^\circ\text{C}$ for 15--16 hours (Mixed LD starter culture, peak diacetyl). Churning Temperature = $9 - 12^\circ\text{C}$.

Answer 1

The Correct Option is C

Step 1: Understanding the Concept:
Cream ripening in cultured butter making: incubation at $20^\circ - 22^\circ ext{C}$ ($21^\circ ext{C}$) for 12--16 hours balances lactic acid production by homofermentative lactococci with diacetyl aroma synthesis by citrate-fermenting leuconostocs.
Key Formula or Approach:
\[ \text{Optimal Cream Ripening: } 20^\circ - 22^\circ\text{C (21}^\circ\text{C)} \text{ for } 15 - 16\text{ Hours} \implies \text{Acidity } 0.2 - 0.4\% \text{ LA} + \text{Diacetyl Peak} \]

Step 2: Detailed Explanation:
In the technology of cultured butter manufacture:
- Cream Ripening: Pasteurised cream is inoculated with a mixed mesophilic aromatic starter culture (Lactococcus lactis ssp. lactis/cremoris for acid production $+$ Leuconostoc mesenteroides ssp. cremoris and Lactococcus lactis ssp. diacetylactis for aroma).
- The standard optimum temperature and duration for cream ripening is 21°C (20° to 22°C) for 15 to 16 hours:
1. At $21^\circ ext{C}$, the growth kinetics of acid-producing and aroma-producing starter strains are perfectly synchronized.
2. Cream develops the ideal churning acidity ($0.20 - 0.40\%$ lactic acid) and maximum concentration of Diacetyl ($2 - 4\text{ ppm}$) for full butter bouquet without developing excess harsh sourness.

Step 3: Final Answer:
Therefore, the optimum condition is 21 °C for 15-16 h, corresponding to option (C).